Final Report Summary - HIPPOCAMP (High-power Impulse Plasma Process Operations for the Creation of Advanced Metallic Parts)
Executive Summary:
European industries such as automotive, aerospace and manufacturing have to develop new structural materials and production processes in order to achieve strict emission reduction requirements and improve performance and multifunctionality. However, advanced engineered materials manufactured today with traditional techniques are prohibitively expensive for many applications and generate unwanted by-products and toxic waste. The HIPPOCAMP project focuses on the development of a robust, high-yield, low cost, environmentally friendly manufacturing process to produce nano- composites for products made of engineered metallic material, in particular, structural components for automotive, aerospace, manufacturing and wind turbine applications.
One of the most desired functional property of such components is vibration damping, because vibration and chatter in turbine blades, machine-tools and other industrial components have very significant consequences: decreased performance, higher maintenance costs, shorter service life and ultimately, higher costs. The HIPPOCAMP project develops a novel method to generate a unique carbon-based composite with high dynamic stiffness material, whose effect on vibration damping will prolong the service life of components, reduce their weight and significantly improve the performance of industrial machineries.
Today, there are no standard structural materials that can simultaneously combine high static stiffness with high damping properties at a broad operating temperature and frequency range. Consequently, there are currently no industrially scalable processes for cost-effectively manufacturing high damping components. The HIPPOCAMP project addresses the development of a scalable industrial process enabling, (i) the synthesis of a new class of nano-composite materials, (ii) the production of these nano-composites on metal or polymer parts, to create industrial components with superior vibration damping property. The project has progressed well with its active work packages and had the second meeting already.
In the first six month, the consortium has focused to set up internal procedures and started to characterize/test the HIPPOCAMP material. Emphasis was laid on the early development of plasma deposition system. A big effort has been dedicated to characterize experimentally the target industrial cases including internal turning, creping, boring and compressor applications. In this tests, the critical frequencies and the best areas for the introduction of the new material has been defined.
In the second six months, we have finalized the specifications & benchmarking part of the project with the definition of all industrial application scenarios. Other significant workpackages are also started and provided their first deliverables at month 12. The consortium has also worked in an exploitation seminar during the two days project meeting. In the months between month 12 and month 18 the consortium continued the work on the plasma deposition system and produced a number of test batches. The samples were analysed and characterized to have the necessary feedback for further improvements. Our life cycle studies have begun as well. In the period between the midterm and month 24 the consortium has finished building the multi cathode system. Thanks to this, we have started to produce the samples in a much improved pace. Several industrial scenarios were concluded in the first iteration. Most significant results were published in high impact journals. The rapid pace of producing samples continued on the following period until month 30. Several iterations were achieved and some key processing bottlenecks were identified. Solutions were proposed to the issues and to all predictions these issues seem to be answerable. In the final 6 months of the project the consortium has managed to install process automation features on the final deposition system. We have achieved very good repeatability and strong materials property features. All work packages were successfully closed.
Project Context and Objectives:
Advanced engineered materials manufactured today with traditional manufacturing techniques and unit operations are prohibitively expensive for many applications due to high capital costs and low production volumes. In addition, byproducts, wastes, and impurities hinder commercial applications. Key European industries such as automotive, aerospace, and manufacturing have to develop new structural materials and production processes in order to achieve strict emission reduction requirements and improve performance and multifunctionality. The cost efficient production of such structural materials with improved functional properties is a key challenge for Europe in the coming years and a key aspect of the EU Economic Recovery Plan.
The HIPPOCAMP project focused on a novel manufacturing process, which required developing nanocomposites and using them as embedded reinforcements to improve the functional properties of products made of engineered metallic material such as structural components for automotive and manufacturing applications. These industrial components share one common problem: they are subject to intense vibrations, which reduce their reliability and durability. Therefore our researchers have sought to reduce the impact of forced vibration and chatter by developing material combining high stiffness with high damping capabilities, a property we will refer to as high dynamic stiffness. High dynamic stiffness (HiDS) material can prolong the service life of components, reduce their weight and significantly improve the performance of industrial machineries. For example, resonant vibrations of turbine blades cause blade fatigue problems in engines, which can lead to thicker and aerodynamically lower performing blade designs, increasing engine weight, fuel burn, and maintenance costs. One important industrial challenge is the development of highly efficient and lighter turbo-engines is that high performance rotating blades are subject to high cycle fatigue (HCF) limitations because of high vibratory stresses. HCF is a major issue for machine tool spindles, automotive turbos, industrial gas turbines, jet engines and wind turbines. For example, HCF accounts for fifty-six percent of major aircraft engine failures and ultimately limits the service life of most critical rotating components. An estimated €8Bn is expended annually for HCF related inspection and maintenance of commercial aircraft alone.
A common method for developing HiDS materials is to combine metallic parts with viscoelastic polymers (VEP). However, these materials have difficulties to bond uniformly to complex shapes, their damping properties are very sensitive to temperature changes, and their effects may be limited in the contact area under high interface pressure (creep effects, also known as stress relaxation). They also deteriorate more quickly than metals during the component lifecycle.
Today, there are no structural materials that can simultaneously combine high static stiffness with high damping properties at a broad operating temperature range. Consequently, there are currently no industrially scalable processes for manufacturing such materials.
In contrast, HiDS materials made of carbon-based nano-composites can provide excellent damping capacity at a wider temperature range, suggesting a great potential for a variety of applications in automotive, aerospace, manufacturing and wind turbine, as well as any structure that is exposed to uncontrollable vibrations. They also endow other key properties such as hardness, fatigue/creep resistance, and wear/corrosion resistance, allowing the development of a new class of multifunctional structural components.
The project addressed the development of a scalable industrial process enabling:
• The synthesis of new class of nano-composites characterized by their high dynamic stiffness properties at a broad range of temperatures (hereafter-called HiDS materials)
• The embedding of nano-composite material on metal or polymer parts, in order to create industrial components with high stiffness-to-weight ratio combined with superior vibration damping property and high thermal stability (hereafter called HiDS components)
Our methodology relied on a bottom-up (additive) technology concept based on three novel approaches:
• PECVD, a plasma-enhanced chemical vapor deposition method using acetylene, oxygen, nitrogen and argon in order to efficiently produce thick layers of material (at high deposition rate) with minimum environmental impact (no use of toxic gases).
• HiPIMS (High-Power Impulse Magnetron Sputtering technology), a physical vapor deposition (PVD) low temperature (100 degrees) method for producing a metal/gas plasma and generating a flux of ionized material from a solid metal source (for better layer coverage on complex shapes).
• A tailored nanostructured composite material fabrication by controlling the pulsed metal plasma discharge characteristics and the metal plasma flow intensity.
Project Results:
The project was divided into 8 (the first one being the management) work packages. In the following, we describe the objectives and S&T results for each RTD and OHER work package.
WP2 Specifications & Benchmarking
This work package combines all the activities required to specify the HIDS components specifications in the target industrial application scenarios and the Industrial Application Description Report. With the help of the industrial partners of the consortium established the industrial constraints to which the parts are subjected to (vibration, chatter, operating temperature, etc.) and quantified the benefits of the functional property improvements required. The objectives of this work package are mainly three: define technically the target industrial processes limited by vibrations, define the contour conditions and the best zones for the new material, and finally define the performance of the solution already in the market by means of benchmarking. In the first six month, the first two objectives have beat treated. Two deliverables have been produced Task 2.1: Industrial Application Scenario Description (IDK) and D2.2. Engineered Industrial Part Specification (IDK). In the last semester, the activities have been focused in the last subtask of the work package dealing with the benchmarking activities. In the end of this activity, a third deliverable has been produced with the name of D2.3 Competitive Benchmarking.
WP3 Deep Metal Plasma Diffusion Method
The overall objective of work package 3 is to study the internal process parameters that impact the synthesis of suitable damping materials deposited within WP4 - Process Scaling and Automation. The overall goal of the work package is twofold:
- To develop, characterize, and optimize a plasma process on an existing single source (single cathode) system with special focus on high power impulse magnetron sputtering (HiPIMS) in order to synthesize the required damping coatings.
- To transfer, scale up, and further optimize the existing plasma process to a multi-source (multi-cathode) system with the aim to increase the possibilities of uniform growth on complex-shaped (non-flat surfaces) at an increased deposition rate.
Deposition systems
The single-source deposition system as well as the multi-cathode deposition systems were successfully set up by the WP3 members and are operational at project member Plasmatrix. The systems were set up for coating samples related to the industrial pilot studies. Of greatest interest is the multi-cathode system. It was designed and set up for the proposed hybrid PVD-PECVD process in reactive and non-reactive gases. The deposition system has been equipped by suitable magnetrons, gas controllers, a new rotating substrate holder with pulsed substrate bias, and two high-power pulsed power supplies, developed within the project by project member Ionautics. These industrialized power supplies have the same capabilities as commonly seen in the thin film deposition technology HiPIMS.
Plasma diagnostics
State of the art plasma characterization tools for, such as a Langmuir probe for electron density and temperature measurements in high-pressure operating regimes, calorimetric probes for heat flux measurements, a Sobolewski probe for ion flux measurements, as well as a modified ion meter to measure the ion-to-neutral flux fraction have been developed and successfully used by the members of WP3 in deposition systems at Plasmatrix and IP ASCR. Several of these results have been published in scientific journals.
These tools are able to characterize the plasma parameters (ionization fraction of depositing particles, deposition rate, plasma density, electron temperature, plasma potential, ion flux and thermal flux on the substrate directly at conditions of reactive deposition process.
Other significant results come from the total thermal power density measurements. They showed that the energy influx on the substrate is homogeneous across the target length. We observed the total thermal power density increased with acetylene mass flow rate for all the investigated pulse discharge currents. The total thermal power density decreased with increasing pulse discharge current, which is likely an effect of decreased pulse frequency (decreased duty factor) to keep the same average discharge power. For an acetylene-containing process, it was also found that the ionized flux fraction decreased with increasing pulse discharge current, and increased slightly with the acetylene mass flow rate. This behavior was partly suppressed at greater distances from the target (increased distance from the intense plasma region). As expected the total deposition rate decreased with higher pulse discharge current, likely due to increased back-attraction of ions. In addition, the pulse ion flux density increases with the pulse discharge current at a distance 10 cm from the target but at distance 15 cm the pulse ion flux density is practically independent on the pulse discharge current.
WP 4 Process Scaling & Automation
The objective of this workpackage is to synthesize suitable HiDS materials which can be implemented and optimized for the given application of WP7 Industrial Pilots. WP4 focused on exploring the experimental (external) process parameters in order to control and manipulate the macro- and microstructure of the grown HiDS material. The workpackage will identify key process parameters to optimize the HiDS material properties by examining fundamental links between processes, structures and properties at nano/micro/macro scale, using systematic experimental, theoretical and computational methods in connection with WP5 Nano-Composite Characterization and Simulation.
The overall goals of the work package are:
1. To identify the relationship between the external process parameters and material nano/micro structure characteristics
2. To identify the relationship between the nano/micro structural parameters and the functional material physical properties especially damping, stiffness hardness and temperature range
3. To monitor, control and automate the HiDS manufacturing process
During the project implementation, WP4 created more than 36 different samples combining different process parameters, including process pressure, precursors, cathode materials, discharge shape, etc. Starting from the initial sample with a nano grain size above 40 nm, the work group of WP4 managed to realize the project goal by reducing the grain size towards below 10 nm. Adhesion strength was investigated and improved by utilizing different methods including the cleaning of substrates, the pre-ion-bombardment process, the pre-adhesive-layer and the process parameter optimization.
A publication made in the journal of Carbon had explained the relationship among the external process parameter, the material’s nano/micro structure and the material’s mechanical properties (see ‘FU, Qilin, et al. High dynamic stiffness mechanical structures with nanostructured composite coatings deposited by high power impulse magnetron sputtering. Carbon, 2016, 98: 24-33.’). In general, it can be summarized that,
a. High process peak power and low process pressure delivers nano structured materials with reduced grain sizes.
b. Smaller grain size below 20 nm activates the nano material’s vibration damping property.
c. The nano material’s stiffness and damping are controlled by separated properties and can be obtained simultaneously
The grain size is mainly controlled by the peak power during discharge, instead of the average power. With the same average power, the HiPIMS process can either create a material with oversized nano grains with high discharge frequency, or create a material with reduced nano size grains with low discharge frequency, maintaining the same process temperature on the substrates. The discharge frequency needs to be balanced with the same average power, as too low frequency will lead to substantially high peak power and high residual stress in the coating. There is also an upper limit for the average power which is strongly affecting the process temperature. Up to a certain limit with the average power, the process temperature increases to a level where the chamber construction material start evaporating. With the previous experiments, an optimized discharge parameter setting was found for the double cathode system.
To activate the material’s damping property, the nano grain size was found critical and it must be below 20 nm to activate the sliding effect in the grain boundaries. The finding has a long term scientific impact on answering the origin of vibration damping in materials. It has pointed out the essential characters of materials to possess high vibration damping property, the size of grains or molecules in nano meter range.
The deposition rate is however affected by process parameters that favors the growth of nano sized grains below 20 nm. With growth of grain size above 100nm, the deposition rate was reported higher than 10 μm/hour. With the selected process parameter for growing of nano grain below 20 nm, the deposition rate is approximately 2 μm/hour.
Through the project development, it is clearly demonstrated and confirmed that the material’s elastic modulus and damping property can be obtained simultaneously. The stiffness is mainly controlled by the metal element, and the damping is mainly controlled by the nano grain size. Changing of the metal element will affect the stiffness as well as changing the percentage of metal elements. It is then possible to obtain high dynamic stiffness and high loss factor material by using a different matrix material.
The temperature stability of the coatings was investigated, and it was shown that the coatings were thermally stable for the operating range of envisaged mechanical products.
Adhesion strength was analyzed and it was shown that an adhesive layer is essential to achieve a good bonding between the composite coating and the substrate. It was also found that different adhesive layers are needed for different types of substrate materials.
A new process control unit was fabricated during the project, and realized full control of the process equipment. The subsystems are now connected to the same platform, and it is possible to perform fully automated production processes.
WP 5 Nano-composite Computational Modelling & Material Characterization
Work package was aimed to conduct a comprehensive material characterization of the coating composite produced by PECVD method using HiPIMS technology. The main objectives of WP5 in HIPPOCAMP project were:
• Report a comprehensive micro/nano structure and crystal phase assessment from the coating.
• Provide experimental analysis of damping capacity of the developed composite.
• Understand other functional properties for the coating, e.g. mechanical response and operational temperature.
• Predict behavior of the coating according to the structure through simulation tools.
To achieve the above goals, micro/nano-structure characterization as well as elementary composition and crystal phase assessment were carried out using the follow techniques: scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), micro-Raman spectroscopy and X-ray diffraction (XRD). Functional properties of the coating were also investigated by means of elastic modulus, hardness and operational temperature. In addition, a variety of dynamic stiffness measurement methods were investigated to evaluate the loss factor of the material’s coating. The relative weight of the structural damping in the overall damping of the industrial pilots has been measured. Finally, molecular dynamics simulation was investigated for potentially increasing the level of precision for the modeling of point defect relaxations and stress induced ordering of the coating molecules and grains.
Our results demonstrate that it is possible to generated Cu:CuCNx multi-layer structure and create grain boundaries of nano crystallized structure by applying of PECVD method using HiPIMS technology. In addition, the applied coating is conformational, i.e. it follows the shape from the substrate/tool. EDS elemental composition mapping clearly show that the brighter layers are Cu-enriched layers which are alternated with C-enriched layers reduced in their copper content. In addition, high resolution TEM images reveals that Cu nanocrystals with a size of few nm can be found in both C and Cu enriched fine nanostructures. The measured lattice spacing values of 2.1 Å and 2.4 Å in the high resolution TEM images are in agreement with the reflections found previously in the XRD patterns. These results are discussed in detail in the scientific publication “High dynamic stiffness mechanical structures with nanostructured composite coatings deposited by high power impulse magnetron sputtering” (Carbon 98: 24-33, 2016).
Functional properties of the coating was also addressed in this WP. Mechanical response is a crucial property to evaluate the viscoelastic nature of the developed material and correlate with the damping capacity. In addition, the operational temperature range defines the limitations the final application as well as direct to new approaches in order to increase these range. Our results show that the depending the deposition parameters the coating can achieve elastic modulus in the range of 40 to 65 GPa and hardness in the range of 2 to 4 MPa. Furthermore, a correlation between elastic modulus/hardness and the applied cathode voltage was clearly observed. Although higher cathode voltage increases the elastic modulus and hardness values, it is evident that that also increase internal stress which causes delamination/cracks at high temperatures. Regarding to high temperatures, it was observed that the coating change its morphology due Cu oxidation and eventually cracks (temperatures above 400oC). These results lead to the conclusion that compromises need to be done in order to find the balance between the outcome coating properties. Even more important, it is clear that by controlling the deposition parameters the coating can be tuned towards the desired application.
This WP also investigated corrosion tests for each of the industrial cases and adhesion tests. In general, it seems all testes corrosion media dissolves copper in different degree. Air-oils components were the less corrosive compound. Adhesion tests indicate good adhesion between coating and substrate.
The dynamic stiffness properties of the materials investigated and produced in this project have been measured using different techniques: free decay method, oberst beam test, dynamic mechanical analysis (DMA) and ultra nano hardness testing (UNHT). Every single one of which yielded different results, mostly probably due the different sample requirements and limitations of each technique. In contrast to polymers and other materials, damping capacity under dynamic loading for metal coatings does not have a standard method for accurate evaluation. The “Free decay method” showed the highest loss factor observed was 0.07 and 0.085. By Oberst beam method, the results clearly show an improvement in damping capacity at level 3 when comparing CNx with Cu:CuCNx. DMA analysis were not conclusive due to the highly sensitive displacement sensor (LVDT) built for measuring viscoelastic materials. Although all the current available methods failed to evaluate the material loss factor, modal and machining tests clearly show that the material does present significant improvement in the tool performance regarding to damping. Regarding to the industrial cases, the relative weight of the structural damping in the overall damping of the industrial pilots was measured. The lower is the ratio between the overall damping and the structural damping, the higher is the possibility to increase the damping with coated elements. The investigation has defined grooving operation as the most proper for the coating with a ration of 9 and the quill as the most difficult case with a ratio of 78.
Simulations activities was also carried out in this WP. The results from the material characterization was used to construct a layered microstructure, which has been transferred to CAE environment of ANSYS where it has been subject to different static and dynamic virtual loads. The overall goal of extracting valuable hints for the manufacturing process required an in-depth knowledge about the energy loss mechanism inside the microstructure of the samples. Modelling grain boundary friction with pillar-like shapes that replicate the growth pattern of the CNx molecules during the deposition process have been modeled in great detail, resulting in an increase of RVE (Representative Volume Element) complexity and thus computation time and effort. Instead of MD and RVE, a transient simulation of a coated beam vibration has been performed, including Rayleigh damping parameters for each sublayer material (CuCNx and Cu). The effect of increasing numbers of sublayers and varying thicknesses of these sublayers on frequency and loss factor has been investigated via a virtual “design of experiments” using ANSYS Workbench simulation environment. The number of sublayers coated onto a steel substrate has been varied from 2 up to 16, the sublayer thickness has been varied between 20 to 300 µm. The results showed a correlation between thicker coatings and higher system loss factor as well as between more sublayers and higher system loss factor (when keeping the overall coating thickness the same).
WP 6 Lifecycle Analysis
Whenever a new technique or a product is developed, its environmental impacts should be assessed to give an early warning of environmental hot spots and give feedback to the developers to change the system to more ecofriendly direction. In WP6 the environmental and safety impacts related to the HiDS material lifecycle from grade-to-grave is being assessed. So far the results have shown that one of the biggest environmental impacts lie in the production phase, more precisely in the target production and energy consumption. One of the key objectives is to gain information about the suitable repair and recycling methods for the novel HiDS material. The removal of the coating from the tool as well as possible damages on the tool regarding this process has been investigated. Furthermore, the reuse of removed coating in different applications is being under study. This WP will evaluate:
▪ Safety hazards and residues related to the HiDS material production process.
▪ Short- and long-term effects related to the use of industrial components containing HiDS material.
▪ Repair and recycling methods for the industrial components containing HiDS material.
Life cycle inventory (LCI) is a method of analyzing the resource and environmental profile of a process or a product. It involves creating an inventory of flows from and to nature for a product system. Inventory flows include the inputs of water, energy and raw materials, while outputs accounted for include product(s) manufactured and environmental emissions to land, air and water. Usually it does not attempt to determine the fate of the emissions, or the relative risk to humans or to the environment due to emissions from the system (i.e. what is accomplished in LCIA phase). In this task, gate-to-gate Life Cycle Inventory (LCI) study was performed in order to estimate the resource and environmental profile of the HiDS material production process in Plasmatrix. Special attention was paid to material consumption (solid, liquid, gaseous), toxic substances consumption, energy consumption and waste generation. The inputs consumed the most in HiDS material production processes are copper, gases - especially argon - and energy.
Life Cycle Assessment (LCA) is a technique to address the environmental aspects and potential environmental impacts throughout a product’s life. A cradle-to-grave LCA includes the whole product “life” i.e. the raw material acquisition, production, use, end-of-life, recycling and final disposal. Two international standards - ISO 14040 and ISO 14044 - set the principles & framework and requirements & guidelines, respectively. The aim of this task was to evaluate the environmental impacts associated with the identified inputs and outputs of the HiDS material production process and give recommendations to the coating producers how the process on its own could be improved in a more sustainable direction. Two different approaches were used for the LCA:
- the environmental impact of the production process (cradle-to-gate analysis)
- impact of the total life cycle of industrial parts having the coating.
Regarding to the production process, our results suggested that the plasma processing is the most harmful considering the environmental aspects. The inputs/outputs responsible for the negative impact during the production were electricity and copper (sources and amounts). The impact categories affected the most were non-renewable energy, respiratory inorganics and global warming. The results suggest that the environmental impact of the coating production could be reduced by reducing the energy consumption and/or changing the source to renewable energy, reducing the copper amount and/or enhancing its reuse, and limiting the usage of organic solvents.
In addition, LCA was conducted on two industrial scenarios. In this case, the aim was to get an idea of the potential savings and environmental benefits that could be achieved by adding the coating in the parts. The studies shared the same conclusion that the impact of the production phase is very low compared with the whole life of the part. For the “series vehicles” scenario, a reduction in consumption and emissions was achieved, with an overall gain of 8-9 %. For the “motorsport” scenario, huge savings (-50 %) are possible due to a different usage of the turbocharger and different operative conditions. In “Milling Spindle” scenario, a 6.26 % reduction in the environmental impact was achieved. The electric energy consumption is reduced by 6.81 %, which translates to a saving of 631 € per year. In “Boring Quill” scenario, a 7.38 % reduction in the environmental impact was achieved. The electric energy consumption is reduced by 6.45 %, which means a saving of 1015 € per year.
To complement the LCA studies, a preliminary assessment on the health risks originating from the exposure to the particles released from the deposition chamber to the factory air. According to the results a small amount of nanomaterial is released from the chamber, but the risk for human health is low due to the size and morphology of the agglomerates/particles.
This WP also carried out a comprehensive study on the stability of the HiDS coating in different environments and during short-term and long-term exposure times. The release of HiDS material from the coated parts was studied in multiple different environments/media, via accelerated aging tests and long term decomposition tests. The samples were characterized by means of Field Emission Scanning Electron Microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), optical microscopy and surface roughness analyzer. In addition, simultaneous mass and heat difference measurement with mass spectrometer gas analysis was performed in order to address the release components when the coating is burned out. Color change was observed for all tested environments, i.e. water, cutting fluids, soil and elevated temperatures. However, for water and cutting fluids environment no significant morphological changes were observed. In addition, chemical composition analysis show that copper is dissolving with time when the coating is exposed in water for longer periods. In the case of soil environment, in addition to the color change it is evident the morphological change which was attributed to copper oxidation process. Although the color changes, the coating seems to be resistant to temperatures up to 200oC. Above 200oC, the coating cracks as well as morphological changes were clearly observed. For higher temperatures than 400oC, the copper oxidation process is more evident, but also occurs for temperatures between 200-400oC. Furthermore, when submitting the coating to temperatures up to 1000oC, H2O and CO2 evaporates and carbon content is burned out. In this case, only copper oxide remains in the ashes. Abrasion tests performed in coated cylinder shown to be satisfactory.
Finally, this WP addressed the recycling and end-life treatment of the coating. For the recycling of HiDS materials grinding, different technologies such as milling- , burning- , sintering- , and coating technologies were used and evaluated. With a high energy ball milling process it was possible to mill the large particles into small flakes with an average diameter of (3.2 ± 1.5) µm. These particles can be used to make sintered workpieces in different shapes. It was proven that it is possible to sinter the flakes with a sinter press. The thermal conductivity of the sintered samples was ranging from 7.5 W/(mk) up to 10 W/(mk) and therefore higher compared to the starting material that had a thermal conductivity form 2 W/(mk) up to 5 W/(mk). The sintered materials had an insulating property and could be used for flexible, electrically insulating layers for encapsulation or splinter protection applications. Another possible re-use of the HiDS Materials can be solution processing with coating technologies. For this aim, the material was brought into a stable dispersion by adding a dispersion agent and binder additives to increase viscosity. The dispersion with a solid content of 15 wt.% Cu:CuCNx was used for the screen printing process because the viscosity of this dispersion was higher compared to the one with a solid content of 5 wt.% Cu:CuCNx. Two different substrate materials were coated by screen printing, PET foil and a paper substrate. The characterization of the surface topology resulted in a higher surface roughness of the Cu:CuCNx coating on paper compared to a Cu:CuCNx coating on PET. The roughness of the substrate materials had an impact on the roughness of the coating. The characterization of the hardness of the coating resulted in an improved hardness for a Cu:CuCNx layer on PET. The electrical characterization of the coatings resulted in an insulating behavior independent on the substrate materials.
WP7 Industrial Pilots
Originally four industrial demonstrators were going to design and built. The interest of the project has increased the number of demonstrators and finally nine different industrial case studies has been prepared. During this workpackage, four different iterations has been defined in each case study. This way gradual improvements have been obtained and in some cases the final output is a solution ready for the market.
Coating was not available for the entire consortium in the first part of the workpackage, but finally the coating has been tested in all the case studies. The different case studies have been decomposed in additional demonstrators to maximize the exploitation. In each iteration, the end users (MIRCONA, LANTIER, SORALUCE and DIAD) design and provide parts to be coated by PLASMATRIX. After that the parts are tested by the end users with the help of IDEKO and PLASMATRIX. Finally, all the involved partners have analyzed the situation and some improvements has been considered for the next iteration.
Most significant results
The application of complementary solutions to increase damping has been successful in five real industrial tests:
• This way the application of a TMD in a boring application has increased seven times the material removal rate and the productivity.
• The combination of embeded TMD and spindle speed variation technique has been able to double the overhang of blades in chatter free grooving operations
• The introduction of an additional blade in creping process has reduced between 24 and 38% the vibration level in real tissue paper production conditions.
• The new damped dewatering boxes has been tested in a real paper machine, being able to suppress flutter and the wire speed has doubled.
• A hydrostatic quill has been designed, built and tested. The new element avoids freeting problems and increases the stability in most cases.
The coated elements has been tested in industrial environments. PLASMATRIX has made an important effort, and has delivered coated elements for all the different industrial case studies including boring bars, grooving blades, turning shims, creeping counterblades, milling tools, spindle head main axis and a turbocharger.
The coated elements have shown an improvement in the damping factor between 9% and 62%. In turning, the application of the coated shims has reduced the high frequency vibrations by 54%. However, the coating presents adhesion problems for industrial cases when important zones of the new layer are ground (spindle head or turboshaft). It is important to remark that the coated shims has increased the life expectations of the tool in different turning applications.
WP8 Exploitation, Dissemination, Standardization
Concerning the exploitation of the project outcomes, several activities have been carried out along the project duration in order to define the possible exploitable results and ensure the achieving of the defined exploitation objectives.
An Exploitation Strategy Seminar (ESS) has been undertaken (9th October 2014; Stuttgart) as well as a Business Plan Development Seminar (BPDS) (22nd October 2015; Prague); the first one was a first attempt within the project for the definition of the exploitable results and their characterization. During the second one, a CANVAS model was defined for three of the results, results that were about to be launched to the market. Afterwards, the owner of these three results developed a Business Plan where they identified the problem and the customer/market needs, defined the product, analysed the competition and substitute solutions, identified the main market barriers, defined the unique selling proposition, analysed the potential market and market/sectors/industries to be addressed and potential customers as well as their position in the market.
Listed below the exploitation outcomes of the project:
• 3 new products (already in the market)
• 2 beta-users (industrial implementations)
• 1 patent pending result. 1 patent under study
• 1 trade mark
No specific details have been provided for these exploitable results due to confidentiality issues. If more information would be needed, it is suggested to contact the project coordinator or the contact person for the responsible partner for each exploitable result.
Regarding the public dissemination activities, several dissemination actions have been taken along the project by the partners related to different audiences as scientific, industrial and even policy makers. The table below shows the different dissemination activities carried out along the duration of the HIPPOCAMP project:
• 17 conferences with an estimated audience of 15,600 people: PSE 2016 15th International Conference on Plasma Surface Engineering (Germany) , 66th CIRP GA 2016 (Portugal), 7th International Conference on HIPIMS (UK), E-MRS 2016 SPRING/ FALL MEETING (France), DMMS (Centre for Design & Management of Manufacturing Systems) members meeting (Sweden), etc.
• 14 exhibitions/trade fairs with an estimated audience of 673,170 people: AMB 2016 (Germany), BIEMH 29th International Machine-Tool Exhibition (Spain), MAQPAPER (Spain), METAV 2016 (Germany), Cervinia 2016 (Italy) and Cesana-Sestriere 2016 (Italy), etc.
• 12 industrial publications: WT-Online, Pulp and Paper World, IMHE, Empresa XXI, SVC Bulletin, Professional Motorsport World, etc.
• 9 scientific publications. Another one submitted and two more under preparation:
▪ Munoa, J., X. Beudaert, Z. Dombovari, Y. Altintas, E. Budak, C. Brecher, and G. Stepan. “Chatter Suppression Techniques in Metal Cutting.” CIRP Annals - Manufacturing Technology 65, no. 2 (2016): 785–808. doi:10.1016/j.cirp.2016.06.004.
▪ Bachrathy, Daniel, Jokin Munoa, and Gabor Stepan. “Experimental Validation of Appropriate Axial Immersions for Helical Mills.” The International Journal of Advanced Manufacturing Technology 84, no. 5–8 (May 1, 2016): 1295–1302. doi:10.1007/s00170-015-7748-0.
▪ Fu, Qilin, Gabriela Simone Lorite, Md. Masud-Ur Rashid, Raphael Neuhaus, Martin Cada, Zdenek Hubicka, Olli Pitkänen, et al. “High Dynamic Stiffness Mechanical Structures with Nanostructured Composite Coatings Deposited by High Power Impulse Magnetron Sputtering.” Carbon 98 (March 2016): 24–33. doi:10.1016/j.carbon.2015.10.074.
▪ Fu, Qilin, Gabriela Simone Lorite, Md. Masud-Ur Rashid, Tuula Selkälä, Juha Uusitalo, Geza Toth, Krisztian Kordas, Tomas Österlind, and Cornel Mihai Nicolescu. “Suppressing Tool Chatter with Novel Multi-Layered Nanostructures of Carbon Based Composite Coatings.” Journal of Materials Processing Technology 223 (September 2015): 292–98. doi:10.1016/j.jmatprotec.2015.03.043.
▪ Iglesias, A., J. Munoa, J. Ciurana, Z. Dombovari, and G. Stepan. “Analytical Expressions for Chatter Analysis in Milling Operations with One Dominant Mode.” Journal of Sound and Vibration 375 (August 4, 2016): 403–21. doi:10.1016/j.jsv.2016.04.015.
▪ Lundin, Daniel, Martin Čada, and Zdeněk Hubička. “Ionization of Sputtered Ti, Al, and C Coupled with Plasma Characterization in HiPIMS.” ResearchGate 24, no. 3 (May 1, 2015). doi:10.1088/0963-0252/24/3/035018.
▪ Lundin, Daniel, Martin Čada, and Zdenĕk Hubička. “Time-Resolved Ion Flux and Impedance Measurements for Process Characterization in Reactive High-Power Impulse Magnetron Sputtering.” Journal of Vacuum Science & Technology A 34, no. 4 (July 1, 2016): 041305. doi:10.1116/1.4953033.
▪ Munoa, Jokin, Alex Iglesias, Aitor Olarra, Zoltan Dombovari, Mikel Zatarain, and Gabor Stepan. “Design of Self-Tuneable Mass Damper for Modular Fixturing Systems.” CIRP Annals - Manufacturing Technology 65, no. 1 (2016): 389–92. doi:10.1016/j.cirp.2016.04.112.
▪ Pitkänen, O., G. S. Lorite, G. Shi, A.-R. Rautio, A. Uusimäki, R. Vajtai, G. Tóth, and K. Kordás. “The Effect of Al Buffer Layer on the Catalytic Synthesis of Carbon Nanotube Forests.” Topics in Catalysis 58, no. 14–17 (October 1, 2015): 1112–18. doi:10.1007/s11244-015-0479-5.
• 2 Doctoral Thesis partly supported by the project:
▪ Milling stability improvement through novel prediction and suppression techniques (A.Iglesias – IK4-Ideko).
▪ High dynamic stiffness nano-structured composites for vibration control: A Study of applications in joint interfaces and machining systems (Q.Fu – Plasmatrix).
• 8 videos related to the industrial cases developed within the project.
Potential Impact:
HIPPOCAMP worked on the industries targeted by the European Economic Recovery Plan which have recently seen demand plummet as a result of the crisis and which face significant challenges in the transition to the green economy. The industrial applications of HiDS components focused on the manufacturing (rotational machine tools) and the automotive (turbo machinery and other automotive mechanical parts) industries.
HIPPOCAMP is also aligned with the objectives of the ‘Factory of the Future’ Public-Private Partnership listed in the workprogramme: increasing the technological base of EU manufacturing through the development and integration of the enabling technologies of the future, such as engineering technologies for adaptable machines and industrial processes and the novel industrial handling of advanced materials. It is an industry-led R&D project that includes demonstration activities, specifically a large-scale demonstrator of the Deep Metal Plasma Diffusion process, a cost-efficient and environmentally-friendly method for shaping, handling and assembling products composed of complex and novel materials.
Our Deep Metal Plasma Diffusion process could also become an enabling technology for bringing back manufacturing to high wage economies such as EC member states. The flexibility and reconfigurabilty of the system means that the same equipment can be used for the manufacturing of different components simultaneously and sequentially. Therefore the process can cost efficiently support low volume production, which opens up the potential for localized production. It is possible to envision a lowcost system that could be deployed in regional “HiDS processing” hubs located in various European countries.
In a machining operation, vibration is a frequent problem, which affects the machining performance and in particular, the surface finish and tool life. Severe vibration occurs in the machining environment due to a dynamic motion between the cutting tool and the workpiece. In all the cutting operations like turning, boring and milling, vibrations are induced due to the deformation of the workpiece, machine structure and cutting tool.
Today, the standard procedure adopted to avoid vibration during machining is by careful planning of the cutting parameters or damping of the cutting tool. The methods adopted to reduce vibration are based on experience as well as trial and error to obtain suitable cutting parameters for each cutting operation. There is only one type of vibration damped tool on the market based on a cavity in the tool shank filled with an oil emulsion and a “balance weight” which can be moved along the axis of the tool holder, so the tool can be calibrated for dampening of different vibration frequencies, but these tools are 10 times more expensive conventional tool parts (100-500 Euros), therefore they are used for high performance machine-tools, which represents a low volume.
Our project developed several methods to produce vibration damped tools based on nano-composite embedded reinforcements (HiDS material) and novel tuned mass dampers that could be sold at a significant cost advantage (65% cheaper than normal damping tools). Such products have a large number of applications in rotational tools such as boring mills, parting off/grooving tools, external turning tools and threading tools. It is expected that the vibration damping improvement will increase the productivity of the machine tool by 2 to 4 times, by improving the metal removal rate and the surface finish, as well as decreasing the rework for bad parts. This generate a massive production cost decrease, as the staff costs and machine tool costs represent 70% of the productions costs of a normal machining process.
Even when accounting for the extra-cost of the cutting tool reinforced by HiDS material, the production cost for the improved machine-tool should be reduced by at least 30%, which is significant for high value part such as aerospace components.
The applications of HiDS material are significant, as the global market for metal-cutting machine tools was forecasted to expand 8.6% annually to 60Bn Euros in 2014, with metal cutting tools accounting for a majority of this market, and rotational tools representing 25% of the total cutting tools.
The environmental impact of the project can be divided in two main categories
• The benefits of the Deep Metal Plasma Diffusion process compared to alternative nano-synthesis methods (lower energy and raw material consumption, no use of toxic gases, etc.)
• The benefits of HiDS components compared to conventional components (productivity, duration of life, carbon footprint, recycling & repair capabilities)
The Deep Metal Plasma Diffusion process is a high yield, low energy, environmentally friendly method for developing carbon nanotube – metal matrix composites. The process uses non toxic gases such as argon, oxygen, nitrogen and acetylen. The innovative combination of PVD/HiPIMS and PECVD reduces the energy requirements (no substrate heating, use of pulsed plasma discharge) while still allowing a high deposition rate on multiple parts at the same time (batch-processing). This is a major improvement over other nanosynthesis methods such as thermal spraying or powder.
HiDS components have the potential to support a greener manufacturing or automotive/aeronautical industries. By reducing vibration in industrial machine-tools, they improve their efficiency and duration of life, therefore significantly reduce the carbon footprint of these industrial production systems. By reducing the turbo-lag in automotive engines, they can generate substantial energy savings. By reducing the weight of aeronautical components, they can significantly decrease aircraft energy consumption.
The project implemented a full lifecycle analysis (LCA), following the ISO 14040:2006 standard (Environmental management -- Life cycle assessment -- Principles and framework). Often, LCA studies fail to capture the full lifecycle of the material because they primarily follow a ‘cradle to gate’ scenario, leaving out the market use and end of life scenarios. The project will address these shortcomings by studying in details recycling and repair alternatives, in order to determine the end of life scenarios of the HiDS material and the HiDS industrial components. For example, repair technologies such as plasma etching were studied to re-deposit or re-use the nano-composite after mechanical grinding of the old layer.
The project has carried out a through plan an assessment of the project results. These plans (Plan for the Use and the Dissemination of Foreground - PUDF) were reported and updated in the framework of WP8. Exploitation, Dissemination, Standardization. The Plan for the Use and the Dissemination of Foreground summarizes the strategy and the concrete actions for the protection, exploitation and dissemination of the results generated by the project.
The PUDF it is structured in two parts: the first describing the strategy and the concrete actions for exploitation of the project’s results and, the second, concerning dissemination. Information is presented by exploitable result to facilitate usability by partners.
The project has produced 9 project publications (peer reviewed publication) with an additional few in draft phase. Carried out a large (45) number of project dissemination activities (e.g. exhibitions, posters, flyers, conferences, press releases, oral presentations, videos, etc.). We have filed for a trademark (M14/009) and a patent (16501850). Finally, we have identified 14 exploitable foregrounds to be followed through our industrial partners.
List of Websites:
http://www.hippocamp.eu/
Project contact: Dr. Geza Toth, University of Oulu.
Email: geza.toth@oulu.fi
European industries such as automotive, aerospace and manufacturing have to develop new structural materials and production processes in order to achieve strict emission reduction requirements and improve performance and multifunctionality. However, advanced engineered materials manufactured today with traditional techniques are prohibitively expensive for many applications and generate unwanted by-products and toxic waste. The HIPPOCAMP project focuses on the development of a robust, high-yield, low cost, environmentally friendly manufacturing process to produce nano- composites for products made of engineered metallic material, in particular, structural components for automotive, aerospace, manufacturing and wind turbine applications.
One of the most desired functional property of such components is vibration damping, because vibration and chatter in turbine blades, machine-tools and other industrial components have very significant consequences: decreased performance, higher maintenance costs, shorter service life and ultimately, higher costs. The HIPPOCAMP project develops a novel method to generate a unique carbon-based composite with high dynamic stiffness material, whose effect on vibration damping will prolong the service life of components, reduce their weight and significantly improve the performance of industrial machineries.
Today, there are no standard structural materials that can simultaneously combine high static stiffness with high damping properties at a broad operating temperature and frequency range. Consequently, there are currently no industrially scalable processes for cost-effectively manufacturing high damping components. The HIPPOCAMP project addresses the development of a scalable industrial process enabling, (i) the synthesis of a new class of nano-composite materials, (ii) the production of these nano-composites on metal or polymer parts, to create industrial components with superior vibration damping property. The project has progressed well with its active work packages and had the second meeting already.
In the first six month, the consortium has focused to set up internal procedures and started to characterize/test the HIPPOCAMP material. Emphasis was laid on the early development of plasma deposition system. A big effort has been dedicated to characterize experimentally the target industrial cases including internal turning, creping, boring and compressor applications. In this tests, the critical frequencies and the best areas for the introduction of the new material has been defined.
In the second six months, we have finalized the specifications & benchmarking part of the project with the definition of all industrial application scenarios. Other significant workpackages are also started and provided their first deliverables at month 12. The consortium has also worked in an exploitation seminar during the two days project meeting. In the months between month 12 and month 18 the consortium continued the work on the plasma deposition system and produced a number of test batches. The samples were analysed and characterized to have the necessary feedback for further improvements. Our life cycle studies have begun as well. In the period between the midterm and month 24 the consortium has finished building the multi cathode system. Thanks to this, we have started to produce the samples in a much improved pace. Several industrial scenarios were concluded in the first iteration. Most significant results were published in high impact journals. The rapid pace of producing samples continued on the following period until month 30. Several iterations were achieved and some key processing bottlenecks were identified. Solutions were proposed to the issues and to all predictions these issues seem to be answerable. In the final 6 months of the project the consortium has managed to install process automation features on the final deposition system. We have achieved very good repeatability and strong materials property features. All work packages were successfully closed.
Project Context and Objectives:
Advanced engineered materials manufactured today with traditional manufacturing techniques and unit operations are prohibitively expensive for many applications due to high capital costs and low production volumes. In addition, byproducts, wastes, and impurities hinder commercial applications. Key European industries such as automotive, aerospace, and manufacturing have to develop new structural materials and production processes in order to achieve strict emission reduction requirements and improve performance and multifunctionality. The cost efficient production of such structural materials with improved functional properties is a key challenge for Europe in the coming years and a key aspect of the EU Economic Recovery Plan.
The HIPPOCAMP project focused on a novel manufacturing process, which required developing nanocomposites and using them as embedded reinforcements to improve the functional properties of products made of engineered metallic material such as structural components for automotive and manufacturing applications. These industrial components share one common problem: they are subject to intense vibrations, which reduce their reliability and durability. Therefore our researchers have sought to reduce the impact of forced vibration and chatter by developing material combining high stiffness with high damping capabilities, a property we will refer to as high dynamic stiffness. High dynamic stiffness (HiDS) material can prolong the service life of components, reduce their weight and significantly improve the performance of industrial machineries. For example, resonant vibrations of turbine blades cause blade fatigue problems in engines, which can lead to thicker and aerodynamically lower performing blade designs, increasing engine weight, fuel burn, and maintenance costs. One important industrial challenge is the development of highly efficient and lighter turbo-engines is that high performance rotating blades are subject to high cycle fatigue (HCF) limitations because of high vibratory stresses. HCF is a major issue for machine tool spindles, automotive turbos, industrial gas turbines, jet engines and wind turbines. For example, HCF accounts for fifty-six percent of major aircraft engine failures and ultimately limits the service life of most critical rotating components. An estimated €8Bn is expended annually for HCF related inspection and maintenance of commercial aircraft alone.
A common method for developing HiDS materials is to combine metallic parts with viscoelastic polymers (VEP). However, these materials have difficulties to bond uniformly to complex shapes, their damping properties are very sensitive to temperature changes, and their effects may be limited in the contact area under high interface pressure (creep effects, also known as stress relaxation). They also deteriorate more quickly than metals during the component lifecycle.
Today, there are no structural materials that can simultaneously combine high static stiffness with high damping properties at a broad operating temperature range. Consequently, there are currently no industrially scalable processes for manufacturing such materials.
In contrast, HiDS materials made of carbon-based nano-composites can provide excellent damping capacity at a wider temperature range, suggesting a great potential for a variety of applications in automotive, aerospace, manufacturing and wind turbine, as well as any structure that is exposed to uncontrollable vibrations. They also endow other key properties such as hardness, fatigue/creep resistance, and wear/corrosion resistance, allowing the development of a new class of multifunctional structural components.
The project addressed the development of a scalable industrial process enabling:
• The synthesis of new class of nano-composites characterized by their high dynamic stiffness properties at a broad range of temperatures (hereafter-called HiDS materials)
• The embedding of nano-composite material on metal or polymer parts, in order to create industrial components with high stiffness-to-weight ratio combined with superior vibration damping property and high thermal stability (hereafter called HiDS components)
Our methodology relied on a bottom-up (additive) technology concept based on three novel approaches:
• PECVD, a plasma-enhanced chemical vapor deposition method using acetylene, oxygen, nitrogen and argon in order to efficiently produce thick layers of material (at high deposition rate) with minimum environmental impact (no use of toxic gases).
• HiPIMS (High-Power Impulse Magnetron Sputtering technology), a physical vapor deposition (PVD) low temperature (100 degrees) method for producing a metal/gas plasma and generating a flux of ionized material from a solid metal source (for better layer coverage on complex shapes).
• A tailored nanostructured composite material fabrication by controlling the pulsed metal plasma discharge characteristics and the metal plasma flow intensity.
Project Results:
The project was divided into 8 (the first one being the management) work packages. In the following, we describe the objectives and S&T results for each RTD and OHER work package.
WP2 Specifications & Benchmarking
This work package combines all the activities required to specify the HIDS components specifications in the target industrial application scenarios and the Industrial Application Description Report. With the help of the industrial partners of the consortium established the industrial constraints to which the parts are subjected to (vibration, chatter, operating temperature, etc.) and quantified the benefits of the functional property improvements required. The objectives of this work package are mainly three: define technically the target industrial processes limited by vibrations, define the contour conditions and the best zones for the new material, and finally define the performance of the solution already in the market by means of benchmarking. In the first six month, the first two objectives have beat treated. Two deliverables have been produced Task 2.1: Industrial Application Scenario Description (IDK) and D2.2. Engineered Industrial Part Specification (IDK). In the last semester, the activities have been focused in the last subtask of the work package dealing with the benchmarking activities. In the end of this activity, a third deliverable has been produced with the name of D2.3 Competitive Benchmarking.
WP3 Deep Metal Plasma Diffusion Method
The overall objective of work package 3 is to study the internal process parameters that impact the synthesis of suitable damping materials deposited within WP4 - Process Scaling and Automation. The overall goal of the work package is twofold:
- To develop, characterize, and optimize a plasma process on an existing single source (single cathode) system with special focus on high power impulse magnetron sputtering (HiPIMS) in order to synthesize the required damping coatings.
- To transfer, scale up, and further optimize the existing plasma process to a multi-source (multi-cathode) system with the aim to increase the possibilities of uniform growth on complex-shaped (non-flat surfaces) at an increased deposition rate.
Deposition systems
The single-source deposition system as well as the multi-cathode deposition systems were successfully set up by the WP3 members and are operational at project member Plasmatrix. The systems were set up for coating samples related to the industrial pilot studies. Of greatest interest is the multi-cathode system. It was designed and set up for the proposed hybrid PVD-PECVD process in reactive and non-reactive gases. The deposition system has been equipped by suitable magnetrons, gas controllers, a new rotating substrate holder with pulsed substrate bias, and two high-power pulsed power supplies, developed within the project by project member Ionautics. These industrialized power supplies have the same capabilities as commonly seen in the thin film deposition technology HiPIMS.
Plasma diagnostics
State of the art plasma characterization tools for, such as a Langmuir probe for electron density and temperature measurements in high-pressure operating regimes, calorimetric probes for heat flux measurements, a Sobolewski probe for ion flux measurements, as well as a modified ion meter to measure the ion-to-neutral flux fraction have been developed and successfully used by the members of WP3 in deposition systems at Plasmatrix and IP ASCR. Several of these results have been published in scientific journals.
These tools are able to characterize the plasma parameters (ionization fraction of depositing particles, deposition rate, plasma density, electron temperature, plasma potential, ion flux and thermal flux on the substrate directly at conditions of reactive deposition process.
Other significant results come from the total thermal power density measurements. They showed that the energy influx on the substrate is homogeneous across the target length. We observed the total thermal power density increased with acetylene mass flow rate for all the investigated pulse discharge currents. The total thermal power density decreased with increasing pulse discharge current, which is likely an effect of decreased pulse frequency (decreased duty factor) to keep the same average discharge power. For an acetylene-containing process, it was also found that the ionized flux fraction decreased with increasing pulse discharge current, and increased slightly with the acetylene mass flow rate. This behavior was partly suppressed at greater distances from the target (increased distance from the intense plasma region). As expected the total deposition rate decreased with higher pulse discharge current, likely due to increased back-attraction of ions. In addition, the pulse ion flux density increases with the pulse discharge current at a distance 10 cm from the target but at distance 15 cm the pulse ion flux density is practically independent on the pulse discharge current.
WP 4 Process Scaling & Automation
The objective of this workpackage is to synthesize suitable HiDS materials which can be implemented and optimized for the given application of WP7 Industrial Pilots. WP4 focused on exploring the experimental (external) process parameters in order to control and manipulate the macro- and microstructure of the grown HiDS material. The workpackage will identify key process parameters to optimize the HiDS material properties by examining fundamental links between processes, structures and properties at nano/micro/macro scale, using systematic experimental, theoretical and computational methods in connection with WP5 Nano-Composite Characterization and Simulation.
The overall goals of the work package are:
1. To identify the relationship between the external process parameters and material nano/micro structure characteristics
2. To identify the relationship between the nano/micro structural parameters and the functional material physical properties especially damping, stiffness hardness and temperature range
3. To monitor, control and automate the HiDS manufacturing process
During the project implementation, WP4 created more than 36 different samples combining different process parameters, including process pressure, precursors, cathode materials, discharge shape, etc. Starting from the initial sample with a nano grain size above 40 nm, the work group of WP4 managed to realize the project goal by reducing the grain size towards below 10 nm. Adhesion strength was investigated and improved by utilizing different methods including the cleaning of substrates, the pre-ion-bombardment process, the pre-adhesive-layer and the process parameter optimization.
A publication made in the journal of Carbon had explained the relationship among the external process parameter, the material’s nano/micro structure and the material’s mechanical properties (see ‘FU, Qilin, et al. High dynamic stiffness mechanical structures with nanostructured composite coatings deposited by high power impulse magnetron sputtering. Carbon, 2016, 98: 24-33.’). In general, it can be summarized that,
a. High process peak power and low process pressure delivers nano structured materials with reduced grain sizes.
b. Smaller grain size below 20 nm activates the nano material’s vibration damping property.
c. The nano material’s stiffness and damping are controlled by separated properties and can be obtained simultaneously
The grain size is mainly controlled by the peak power during discharge, instead of the average power. With the same average power, the HiPIMS process can either create a material with oversized nano grains with high discharge frequency, or create a material with reduced nano size grains with low discharge frequency, maintaining the same process temperature on the substrates. The discharge frequency needs to be balanced with the same average power, as too low frequency will lead to substantially high peak power and high residual stress in the coating. There is also an upper limit for the average power which is strongly affecting the process temperature. Up to a certain limit with the average power, the process temperature increases to a level where the chamber construction material start evaporating. With the previous experiments, an optimized discharge parameter setting was found for the double cathode system.
To activate the material’s damping property, the nano grain size was found critical and it must be below 20 nm to activate the sliding effect in the grain boundaries. The finding has a long term scientific impact on answering the origin of vibration damping in materials. It has pointed out the essential characters of materials to possess high vibration damping property, the size of grains or molecules in nano meter range.
The deposition rate is however affected by process parameters that favors the growth of nano sized grains below 20 nm. With growth of grain size above 100nm, the deposition rate was reported higher than 10 μm/hour. With the selected process parameter for growing of nano grain below 20 nm, the deposition rate is approximately 2 μm/hour.
Through the project development, it is clearly demonstrated and confirmed that the material’s elastic modulus and damping property can be obtained simultaneously. The stiffness is mainly controlled by the metal element, and the damping is mainly controlled by the nano grain size. Changing of the metal element will affect the stiffness as well as changing the percentage of metal elements. It is then possible to obtain high dynamic stiffness and high loss factor material by using a different matrix material.
The temperature stability of the coatings was investigated, and it was shown that the coatings were thermally stable for the operating range of envisaged mechanical products.
Adhesion strength was analyzed and it was shown that an adhesive layer is essential to achieve a good bonding between the composite coating and the substrate. It was also found that different adhesive layers are needed for different types of substrate materials.
A new process control unit was fabricated during the project, and realized full control of the process equipment. The subsystems are now connected to the same platform, and it is possible to perform fully automated production processes.
WP 5 Nano-composite Computational Modelling & Material Characterization
Work package was aimed to conduct a comprehensive material characterization of the coating composite produced by PECVD method using HiPIMS technology. The main objectives of WP5 in HIPPOCAMP project were:
• Report a comprehensive micro/nano structure and crystal phase assessment from the coating.
• Provide experimental analysis of damping capacity of the developed composite.
• Understand other functional properties for the coating, e.g. mechanical response and operational temperature.
• Predict behavior of the coating according to the structure through simulation tools.
To achieve the above goals, micro/nano-structure characterization as well as elementary composition and crystal phase assessment were carried out using the follow techniques: scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), micro-Raman spectroscopy and X-ray diffraction (XRD). Functional properties of the coating were also investigated by means of elastic modulus, hardness and operational temperature. In addition, a variety of dynamic stiffness measurement methods were investigated to evaluate the loss factor of the material’s coating. The relative weight of the structural damping in the overall damping of the industrial pilots has been measured. Finally, molecular dynamics simulation was investigated for potentially increasing the level of precision for the modeling of point defect relaxations and stress induced ordering of the coating molecules and grains.
Our results demonstrate that it is possible to generated Cu:CuCNx multi-layer structure and create grain boundaries of nano crystallized structure by applying of PECVD method using HiPIMS technology. In addition, the applied coating is conformational, i.e. it follows the shape from the substrate/tool. EDS elemental composition mapping clearly show that the brighter layers are Cu-enriched layers which are alternated with C-enriched layers reduced in their copper content. In addition, high resolution TEM images reveals that Cu nanocrystals with a size of few nm can be found in both C and Cu enriched fine nanostructures. The measured lattice spacing values of 2.1 Å and 2.4 Å in the high resolution TEM images are in agreement with the reflections found previously in the XRD patterns. These results are discussed in detail in the scientific publication “High dynamic stiffness mechanical structures with nanostructured composite coatings deposited by high power impulse magnetron sputtering” (Carbon 98: 24-33, 2016).
Functional properties of the coating was also addressed in this WP. Mechanical response is a crucial property to evaluate the viscoelastic nature of the developed material and correlate with the damping capacity. In addition, the operational temperature range defines the limitations the final application as well as direct to new approaches in order to increase these range. Our results show that the depending the deposition parameters the coating can achieve elastic modulus in the range of 40 to 65 GPa and hardness in the range of 2 to 4 MPa. Furthermore, a correlation between elastic modulus/hardness and the applied cathode voltage was clearly observed. Although higher cathode voltage increases the elastic modulus and hardness values, it is evident that that also increase internal stress which causes delamination/cracks at high temperatures. Regarding to high temperatures, it was observed that the coating change its morphology due Cu oxidation and eventually cracks (temperatures above 400oC). These results lead to the conclusion that compromises need to be done in order to find the balance between the outcome coating properties. Even more important, it is clear that by controlling the deposition parameters the coating can be tuned towards the desired application.
This WP also investigated corrosion tests for each of the industrial cases and adhesion tests. In general, it seems all testes corrosion media dissolves copper in different degree. Air-oils components were the less corrosive compound. Adhesion tests indicate good adhesion between coating and substrate.
The dynamic stiffness properties of the materials investigated and produced in this project have been measured using different techniques: free decay method, oberst beam test, dynamic mechanical analysis (DMA) and ultra nano hardness testing (UNHT). Every single one of which yielded different results, mostly probably due the different sample requirements and limitations of each technique. In contrast to polymers and other materials, damping capacity under dynamic loading for metal coatings does not have a standard method for accurate evaluation. The “Free decay method” showed the highest loss factor observed was 0.07 and 0.085. By Oberst beam method, the results clearly show an improvement in damping capacity at level 3 when comparing CNx with Cu:CuCNx. DMA analysis were not conclusive due to the highly sensitive displacement sensor (LVDT) built for measuring viscoelastic materials. Although all the current available methods failed to evaluate the material loss factor, modal and machining tests clearly show that the material does present significant improvement in the tool performance regarding to damping. Regarding to the industrial cases, the relative weight of the structural damping in the overall damping of the industrial pilots was measured. The lower is the ratio between the overall damping and the structural damping, the higher is the possibility to increase the damping with coated elements. The investigation has defined grooving operation as the most proper for the coating with a ration of 9 and the quill as the most difficult case with a ratio of 78.
Simulations activities was also carried out in this WP. The results from the material characterization was used to construct a layered microstructure, which has been transferred to CAE environment of ANSYS where it has been subject to different static and dynamic virtual loads. The overall goal of extracting valuable hints for the manufacturing process required an in-depth knowledge about the energy loss mechanism inside the microstructure of the samples. Modelling grain boundary friction with pillar-like shapes that replicate the growth pattern of the CNx molecules during the deposition process have been modeled in great detail, resulting in an increase of RVE (Representative Volume Element) complexity and thus computation time and effort. Instead of MD and RVE, a transient simulation of a coated beam vibration has been performed, including Rayleigh damping parameters for each sublayer material (CuCNx and Cu). The effect of increasing numbers of sublayers and varying thicknesses of these sublayers on frequency and loss factor has been investigated via a virtual “design of experiments” using ANSYS Workbench simulation environment. The number of sublayers coated onto a steel substrate has been varied from 2 up to 16, the sublayer thickness has been varied between 20 to 300 µm. The results showed a correlation between thicker coatings and higher system loss factor as well as between more sublayers and higher system loss factor (when keeping the overall coating thickness the same).
WP 6 Lifecycle Analysis
Whenever a new technique or a product is developed, its environmental impacts should be assessed to give an early warning of environmental hot spots and give feedback to the developers to change the system to more ecofriendly direction. In WP6 the environmental and safety impacts related to the HiDS material lifecycle from grade-to-grave is being assessed. So far the results have shown that one of the biggest environmental impacts lie in the production phase, more precisely in the target production and energy consumption. One of the key objectives is to gain information about the suitable repair and recycling methods for the novel HiDS material. The removal of the coating from the tool as well as possible damages on the tool regarding this process has been investigated. Furthermore, the reuse of removed coating in different applications is being under study. This WP will evaluate:
▪ Safety hazards and residues related to the HiDS material production process.
▪ Short- and long-term effects related to the use of industrial components containing HiDS material.
▪ Repair and recycling methods for the industrial components containing HiDS material.
Life cycle inventory (LCI) is a method of analyzing the resource and environmental profile of a process or a product. It involves creating an inventory of flows from and to nature for a product system. Inventory flows include the inputs of water, energy and raw materials, while outputs accounted for include product(s) manufactured and environmental emissions to land, air and water. Usually it does not attempt to determine the fate of the emissions, or the relative risk to humans or to the environment due to emissions from the system (i.e. what is accomplished in LCIA phase). In this task, gate-to-gate Life Cycle Inventory (LCI) study was performed in order to estimate the resource and environmental profile of the HiDS material production process in Plasmatrix. Special attention was paid to material consumption (solid, liquid, gaseous), toxic substances consumption, energy consumption and waste generation. The inputs consumed the most in HiDS material production processes are copper, gases - especially argon - and energy.
Life Cycle Assessment (LCA) is a technique to address the environmental aspects and potential environmental impacts throughout a product’s life. A cradle-to-grave LCA includes the whole product “life” i.e. the raw material acquisition, production, use, end-of-life, recycling and final disposal. Two international standards - ISO 14040 and ISO 14044 - set the principles & framework and requirements & guidelines, respectively. The aim of this task was to evaluate the environmental impacts associated with the identified inputs and outputs of the HiDS material production process and give recommendations to the coating producers how the process on its own could be improved in a more sustainable direction. Two different approaches were used for the LCA:
- the environmental impact of the production process (cradle-to-gate analysis)
- impact of the total life cycle of industrial parts having the coating.
Regarding to the production process, our results suggested that the plasma processing is the most harmful considering the environmental aspects. The inputs/outputs responsible for the negative impact during the production were electricity and copper (sources and amounts). The impact categories affected the most were non-renewable energy, respiratory inorganics and global warming. The results suggest that the environmental impact of the coating production could be reduced by reducing the energy consumption and/or changing the source to renewable energy, reducing the copper amount and/or enhancing its reuse, and limiting the usage of organic solvents.
In addition, LCA was conducted on two industrial scenarios. In this case, the aim was to get an idea of the potential savings and environmental benefits that could be achieved by adding the coating in the parts. The studies shared the same conclusion that the impact of the production phase is very low compared with the whole life of the part. For the “series vehicles” scenario, a reduction in consumption and emissions was achieved, with an overall gain of 8-9 %. For the “motorsport” scenario, huge savings (-50 %) are possible due to a different usage of the turbocharger and different operative conditions. In “Milling Spindle” scenario, a 6.26 % reduction in the environmental impact was achieved. The electric energy consumption is reduced by 6.81 %, which translates to a saving of 631 € per year. In “Boring Quill” scenario, a 7.38 % reduction in the environmental impact was achieved. The electric energy consumption is reduced by 6.45 %, which means a saving of 1015 € per year.
To complement the LCA studies, a preliminary assessment on the health risks originating from the exposure to the particles released from the deposition chamber to the factory air. According to the results a small amount of nanomaterial is released from the chamber, but the risk for human health is low due to the size and morphology of the agglomerates/particles.
This WP also carried out a comprehensive study on the stability of the HiDS coating in different environments and during short-term and long-term exposure times. The release of HiDS material from the coated parts was studied in multiple different environments/media, via accelerated aging tests and long term decomposition tests. The samples were characterized by means of Field Emission Scanning Electron Microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), optical microscopy and surface roughness analyzer. In addition, simultaneous mass and heat difference measurement with mass spectrometer gas analysis was performed in order to address the release components when the coating is burned out. Color change was observed for all tested environments, i.e. water, cutting fluids, soil and elevated temperatures. However, for water and cutting fluids environment no significant morphological changes were observed. In addition, chemical composition analysis show that copper is dissolving with time when the coating is exposed in water for longer periods. In the case of soil environment, in addition to the color change it is evident the morphological change which was attributed to copper oxidation process. Although the color changes, the coating seems to be resistant to temperatures up to 200oC. Above 200oC, the coating cracks as well as morphological changes were clearly observed. For higher temperatures than 400oC, the copper oxidation process is more evident, but also occurs for temperatures between 200-400oC. Furthermore, when submitting the coating to temperatures up to 1000oC, H2O and CO2 evaporates and carbon content is burned out. In this case, only copper oxide remains in the ashes. Abrasion tests performed in coated cylinder shown to be satisfactory.
Finally, this WP addressed the recycling and end-life treatment of the coating. For the recycling of HiDS materials grinding, different technologies such as milling- , burning- , sintering- , and coating technologies were used and evaluated. With a high energy ball milling process it was possible to mill the large particles into small flakes with an average diameter of (3.2 ± 1.5) µm. These particles can be used to make sintered workpieces in different shapes. It was proven that it is possible to sinter the flakes with a sinter press. The thermal conductivity of the sintered samples was ranging from 7.5 W/(mk) up to 10 W/(mk) and therefore higher compared to the starting material that had a thermal conductivity form 2 W/(mk) up to 5 W/(mk). The sintered materials had an insulating property and could be used for flexible, electrically insulating layers for encapsulation or splinter protection applications. Another possible re-use of the HiDS Materials can be solution processing with coating technologies. For this aim, the material was brought into a stable dispersion by adding a dispersion agent and binder additives to increase viscosity. The dispersion with a solid content of 15 wt.% Cu:CuCNx was used for the screen printing process because the viscosity of this dispersion was higher compared to the one with a solid content of 5 wt.% Cu:CuCNx. Two different substrate materials were coated by screen printing, PET foil and a paper substrate. The characterization of the surface topology resulted in a higher surface roughness of the Cu:CuCNx coating on paper compared to a Cu:CuCNx coating on PET. The roughness of the substrate materials had an impact on the roughness of the coating. The characterization of the hardness of the coating resulted in an improved hardness for a Cu:CuCNx layer on PET. The electrical characterization of the coatings resulted in an insulating behavior independent on the substrate materials.
WP7 Industrial Pilots
Originally four industrial demonstrators were going to design and built. The interest of the project has increased the number of demonstrators and finally nine different industrial case studies has been prepared. During this workpackage, four different iterations has been defined in each case study. This way gradual improvements have been obtained and in some cases the final output is a solution ready for the market.
Coating was not available for the entire consortium in the first part of the workpackage, but finally the coating has been tested in all the case studies. The different case studies have been decomposed in additional demonstrators to maximize the exploitation. In each iteration, the end users (MIRCONA, LANTIER, SORALUCE and DIAD) design and provide parts to be coated by PLASMATRIX. After that the parts are tested by the end users with the help of IDEKO and PLASMATRIX. Finally, all the involved partners have analyzed the situation and some improvements has been considered for the next iteration.
Most significant results
The application of complementary solutions to increase damping has been successful in five real industrial tests:
• This way the application of a TMD in a boring application has increased seven times the material removal rate and the productivity.
• The combination of embeded TMD and spindle speed variation technique has been able to double the overhang of blades in chatter free grooving operations
• The introduction of an additional blade in creping process has reduced between 24 and 38% the vibration level in real tissue paper production conditions.
• The new damped dewatering boxes has been tested in a real paper machine, being able to suppress flutter and the wire speed has doubled.
• A hydrostatic quill has been designed, built and tested. The new element avoids freeting problems and increases the stability in most cases.
The coated elements has been tested in industrial environments. PLASMATRIX has made an important effort, and has delivered coated elements for all the different industrial case studies including boring bars, grooving blades, turning shims, creeping counterblades, milling tools, spindle head main axis and a turbocharger.
The coated elements have shown an improvement in the damping factor between 9% and 62%. In turning, the application of the coated shims has reduced the high frequency vibrations by 54%. However, the coating presents adhesion problems for industrial cases when important zones of the new layer are ground (spindle head or turboshaft). It is important to remark that the coated shims has increased the life expectations of the tool in different turning applications.
WP8 Exploitation, Dissemination, Standardization
Concerning the exploitation of the project outcomes, several activities have been carried out along the project duration in order to define the possible exploitable results and ensure the achieving of the defined exploitation objectives.
An Exploitation Strategy Seminar (ESS) has been undertaken (9th October 2014; Stuttgart) as well as a Business Plan Development Seminar (BPDS) (22nd October 2015; Prague); the first one was a first attempt within the project for the definition of the exploitable results and their characterization. During the second one, a CANVAS model was defined for three of the results, results that were about to be launched to the market. Afterwards, the owner of these three results developed a Business Plan where they identified the problem and the customer/market needs, defined the product, analysed the competition and substitute solutions, identified the main market barriers, defined the unique selling proposition, analysed the potential market and market/sectors/industries to be addressed and potential customers as well as their position in the market.
Listed below the exploitation outcomes of the project:
• 3 new products (already in the market)
• 2 beta-users (industrial implementations)
• 1 patent pending result. 1 patent under study
• 1 trade mark
No specific details have been provided for these exploitable results due to confidentiality issues. If more information would be needed, it is suggested to contact the project coordinator or the contact person for the responsible partner for each exploitable result.
Regarding the public dissemination activities, several dissemination actions have been taken along the project by the partners related to different audiences as scientific, industrial and even policy makers. The table below shows the different dissemination activities carried out along the duration of the HIPPOCAMP project:
• 17 conferences with an estimated audience of 15,600 people: PSE 2016 15th International Conference on Plasma Surface Engineering (Germany) , 66th CIRP GA 2016 (Portugal), 7th International Conference on HIPIMS (UK), E-MRS 2016 SPRING/ FALL MEETING (France), DMMS (Centre for Design & Management of Manufacturing Systems) members meeting (Sweden), etc.
• 14 exhibitions/trade fairs with an estimated audience of 673,170 people: AMB 2016 (Germany), BIEMH 29th International Machine-Tool Exhibition (Spain), MAQPAPER (Spain), METAV 2016 (Germany), Cervinia 2016 (Italy) and Cesana-Sestriere 2016 (Italy), etc.
• 12 industrial publications: WT-Online, Pulp and Paper World, IMHE, Empresa XXI, SVC Bulletin, Professional Motorsport World, etc.
• 9 scientific publications. Another one submitted and two more under preparation:
▪ Munoa, J., X. Beudaert, Z. Dombovari, Y. Altintas, E. Budak, C. Brecher, and G. Stepan. “Chatter Suppression Techniques in Metal Cutting.” CIRP Annals - Manufacturing Technology 65, no. 2 (2016): 785–808. doi:10.1016/j.cirp.2016.06.004.
▪ Bachrathy, Daniel, Jokin Munoa, and Gabor Stepan. “Experimental Validation of Appropriate Axial Immersions for Helical Mills.” The International Journal of Advanced Manufacturing Technology 84, no. 5–8 (May 1, 2016): 1295–1302. doi:10.1007/s00170-015-7748-0.
▪ Fu, Qilin, Gabriela Simone Lorite, Md. Masud-Ur Rashid, Raphael Neuhaus, Martin Cada, Zdenek Hubicka, Olli Pitkänen, et al. “High Dynamic Stiffness Mechanical Structures with Nanostructured Composite Coatings Deposited by High Power Impulse Magnetron Sputtering.” Carbon 98 (March 2016): 24–33. doi:10.1016/j.carbon.2015.10.074.
▪ Fu, Qilin, Gabriela Simone Lorite, Md. Masud-Ur Rashid, Tuula Selkälä, Juha Uusitalo, Geza Toth, Krisztian Kordas, Tomas Österlind, and Cornel Mihai Nicolescu. “Suppressing Tool Chatter with Novel Multi-Layered Nanostructures of Carbon Based Composite Coatings.” Journal of Materials Processing Technology 223 (September 2015): 292–98. doi:10.1016/j.jmatprotec.2015.03.043.
▪ Iglesias, A., J. Munoa, J. Ciurana, Z. Dombovari, and G. Stepan. “Analytical Expressions for Chatter Analysis in Milling Operations with One Dominant Mode.” Journal of Sound and Vibration 375 (August 4, 2016): 403–21. doi:10.1016/j.jsv.2016.04.015.
▪ Lundin, Daniel, Martin Čada, and Zdeněk Hubička. “Ionization of Sputtered Ti, Al, and C Coupled with Plasma Characterization in HiPIMS.” ResearchGate 24, no. 3 (May 1, 2015). doi:10.1088/0963-0252/24/3/035018.
▪ Lundin, Daniel, Martin Čada, and Zdenĕk Hubička. “Time-Resolved Ion Flux and Impedance Measurements for Process Characterization in Reactive High-Power Impulse Magnetron Sputtering.” Journal of Vacuum Science & Technology A 34, no. 4 (July 1, 2016): 041305. doi:10.1116/1.4953033.
▪ Munoa, Jokin, Alex Iglesias, Aitor Olarra, Zoltan Dombovari, Mikel Zatarain, and Gabor Stepan. “Design of Self-Tuneable Mass Damper for Modular Fixturing Systems.” CIRP Annals - Manufacturing Technology 65, no. 1 (2016): 389–92. doi:10.1016/j.cirp.2016.04.112.
▪ Pitkänen, O., G. S. Lorite, G. Shi, A.-R. Rautio, A. Uusimäki, R. Vajtai, G. Tóth, and K. Kordás. “The Effect of Al Buffer Layer on the Catalytic Synthesis of Carbon Nanotube Forests.” Topics in Catalysis 58, no. 14–17 (October 1, 2015): 1112–18. doi:10.1007/s11244-015-0479-5.
• 2 Doctoral Thesis partly supported by the project:
▪ Milling stability improvement through novel prediction and suppression techniques (A.Iglesias – IK4-Ideko).
▪ High dynamic stiffness nano-structured composites for vibration control: A Study of applications in joint interfaces and machining systems (Q.Fu – Plasmatrix).
• 8 videos related to the industrial cases developed within the project.
Potential Impact:
HIPPOCAMP worked on the industries targeted by the European Economic Recovery Plan which have recently seen demand plummet as a result of the crisis and which face significant challenges in the transition to the green economy. The industrial applications of HiDS components focused on the manufacturing (rotational machine tools) and the automotive (turbo machinery and other automotive mechanical parts) industries.
HIPPOCAMP is also aligned with the objectives of the ‘Factory of the Future’ Public-Private Partnership listed in the workprogramme: increasing the technological base of EU manufacturing through the development and integration of the enabling technologies of the future, such as engineering technologies for adaptable machines and industrial processes and the novel industrial handling of advanced materials. It is an industry-led R&D project that includes demonstration activities, specifically a large-scale demonstrator of the Deep Metal Plasma Diffusion process, a cost-efficient and environmentally-friendly method for shaping, handling and assembling products composed of complex and novel materials.
Our Deep Metal Plasma Diffusion process could also become an enabling technology for bringing back manufacturing to high wage economies such as EC member states. The flexibility and reconfigurabilty of the system means that the same equipment can be used for the manufacturing of different components simultaneously and sequentially. Therefore the process can cost efficiently support low volume production, which opens up the potential for localized production. It is possible to envision a lowcost system that could be deployed in regional “HiDS processing” hubs located in various European countries.
In a machining operation, vibration is a frequent problem, which affects the machining performance and in particular, the surface finish and tool life. Severe vibration occurs in the machining environment due to a dynamic motion between the cutting tool and the workpiece. In all the cutting operations like turning, boring and milling, vibrations are induced due to the deformation of the workpiece, machine structure and cutting tool.
Today, the standard procedure adopted to avoid vibration during machining is by careful planning of the cutting parameters or damping of the cutting tool. The methods adopted to reduce vibration are based on experience as well as trial and error to obtain suitable cutting parameters for each cutting operation. There is only one type of vibration damped tool on the market based on a cavity in the tool shank filled with an oil emulsion and a “balance weight” which can be moved along the axis of the tool holder, so the tool can be calibrated for dampening of different vibration frequencies, but these tools are 10 times more expensive conventional tool parts (100-500 Euros), therefore they are used for high performance machine-tools, which represents a low volume.
Our project developed several methods to produce vibration damped tools based on nano-composite embedded reinforcements (HiDS material) and novel tuned mass dampers that could be sold at a significant cost advantage (65% cheaper than normal damping tools). Such products have a large number of applications in rotational tools such as boring mills, parting off/grooving tools, external turning tools and threading tools. It is expected that the vibration damping improvement will increase the productivity of the machine tool by 2 to 4 times, by improving the metal removal rate and the surface finish, as well as decreasing the rework for bad parts. This generate a massive production cost decrease, as the staff costs and machine tool costs represent 70% of the productions costs of a normal machining process.
Even when accounting for the extra-cost of the cutting tool reinforced by HiDS material, the production cost for the improved machine-tool should be reduced by at least 30%, which is significant for high value part such as aerospace components.
The applications of HiDS material are significant, as the global market for metal-cutting machine tools was forecasted to expand 8.6% annually to 60Bn Euros in 2014, with metal cutting tools accounting for a majority of this market, and rotational tools representing 25% of the total cutting tools.
The environmental impact of the project can be divided in two main categories
• The benefits of the Deep Metal Plasma Diffusion process compared to alternative nano-synthesis methods (lower energy and raw material consumption, no use of toxic gases, etc.)
• The benefits of HiDS components compared to conventional components (productivity, duration of life, carbon footprint, recycling & repair capabilities)
The Deep Metal Plasma Diffusion process is a high yield, low energy, environmentally friendly method for developing carbon nanotube – metal matrix composites. The process uses non toxic gases such as argon, oxygen, nitrogen and acetylen. The innovative combination of PVD/HiPIMS and PECVD reduces the energy requirements (no substrate heating, use of pulsed plasma discharge) while still allowing a high deposition rate on multiple parts at the same time (batch-processing). This is a major improvement over other nanosynthesis methods such as thermal spraying or powder.
HiDS components have the potential to support a greener manufacturing or automotive/aeronautical industries. By reducing vibration in industrial machine-tools, they improve their efficiency and duration of life, therefore significantly reduce the carbon footprint of these industrial production systems. By reducing the turbo-lag in automotive engines, they can generate substantial energy savings. By reducing the weight of aeronautical components, they can significantly decrease aircraft energy consumption.
The project implemented a full lifecycle analysis (LCA), following the ISO 14040:2006 standard (Environmental management -- Life cycle assessment -- Principles and framework). Often, LCA studies fail to capture the full lifecycle of the material because they primarily follow a ‘cradle to gate’ scenario, leaving out the market use and end of life scenarios. The project will address these shortcomings by studying in details recycling and repair alternatives, in order to determine the end of life scenarios of the HiDS material and the HiDS industrial components. For example, repair technologies such as plasma etching were studied to re-deposit or re-use the nano-composite after mechanical grinding of the old layer.
The project has carried out a through plan an assessment of the project results. These plans (Plan for the Use and the Dissemination of Foreground - PUDF) were reported and updated in the framework of WP8. Exploitation, Dissemination, Standardization. The Plan for the Use and the Dissemination of Foreground summarizes the strategy and the concrete actions for the protection, exploitation and dissemination of the results generated by the project.
The PUDF it is structured in two parts: the first describing the strategy and the concrete actions for exploitation of the project’s results and, the second, concerning dissemination. Information is presented by exploitable result to facilitate usability by partners.
The project has produced 9 project publications (peer reviewed publication) with an additional few in draft phase. Carried out a large (45) number of project dissemination activities (e.g. exhibitions, posters, flyers, conferences, press releases, oral presentations, videos, etc.). We have filed for a trademark (M14/009) and a patent (16501850). Finally, we have identified 14 exploitable foregrounds to be followed through our industrial partners.
List of Websites:
http://www.hippocamp.eu/
Project contact: Dr. Geza Toth, University of Oulu.
Email: geza.toth@oulu.fi