Objectif
The objectives of this project are to produce v ery hard ceramic coatings based on boron carbide with high mechanical performance and improved resistance to chemical attack. The first objective especially concerns the oxidation resistance of boron carbide coatings between 600 and 1300C, and the neutralisation of the affinity between boron and iron above 600C during steel machining with coated inserts. The second objective is the reduction of boron diffusion into the substrates during the boron carbide deposition cycle. The project combines three different techniques for coating and doping in order to make diffusion barriers or multi-element compounds: Chemical Vapour Deposition (CVD): multilayer/doped coatings Ion Implantation: diffusion barriers/doping of boron carbide. Molten Salts Deposition: diffusion barriers. The substrates to be coated are cemented carbides and mainly several kinds of steel.
Cutting tests on aluminium/silicon and cast iron showed that the lifetime of cemented carbide cutting tools coated with titanium doped boron carbide is increased by a factor of 5 and 8 respectively. A diffusion barrier for boron carbide deposition on steel as well as on cemented carbide was developed. Attempts to dope boron carbide with titanium and silicon in order to improve its chemical properties at high temperatures were made. Boron carbide doped with titanium showed a moderate increase in weld resistance.
Vanadium, chromium, silicon and titanium carbide diffusion barriers were tested. Of these only titanium carbide was successful.
Doping of boron carbide led to amorphous coatings, whereas multiphase coatings with titanium created in hot wall low pressure chemical vapour deposition (LPCVD) led to uniform titanium borate coatings.
Cutting tests showed that such materials used to coat several types of cutting, drilling and boring tools increased wear resistance.
THE PROJECT CONSISTS OF AN ORIGINAL TECHNIQUE OF DEPOSIT BY CHEMICAL VAPOUR DEPOSITION (CVD) AND BY IONIC IMPLANTATION:
- IONIC IMPLANTATION AT A TEMPERATURE BELOW 150 CELSIUS DEGREES.
- MULTILAYER AND DOPED DEPOSIT BY CVD IN A SINGLE THERMAL CYCLE.
- THERMAL TREATMENT OF STEEL SUBSTRATES LINED WITH DOPED BORON CARBIDE.
- NEUTRALISATION OF THE AFFINITY BETWEEN THE BORON AND THE IRON AT A TEMPERATURE ABOVE 600 CELSIUS DEGREES.
IF SUCCESSFUL, THE ECONOMIC BENEFITS OF THE PROJECT ARE GUARANTED BY THE IMPORTANCE OF THE DIFFERENT INDUSTRIAL APPLICATIONS ENVISAGED:
- PROTECTION AGAINST WEAR OF NON-LUBRIFIED MECHANICAL ELEMENTS
- REALISATION OF MECHANICAL PROSTHESIS
- RESISTANCE VERSUS FATIGUE, ABRASION AND CORROSION OF MECHANICAL ELEMENTS USED IN DIFFERENT INDUSTRIES LIKE CHEMISTRY, OIL, TEXTILE, ETC...
Champ scientifique (EuroSciVoc)
CORDIS classe les projets avec EuroSciVoc, une taxonomie multilingue des domaines scientifiques, grâce à un processus semi-automatique basé sur des techniques TLN.
CORDIS classe les projets avec EuroSciVoc, une taxonomie multilingue des domaines scientifiques, grâce à un processus semi-automatique basé sur des techniques TLN.
- sciences naturellessciences chimiqueschimie inorganiquecomposé inorganique
- sciences naturellessciences chimiqueschimie inorganiquemétal de transition
- ingénierie et technologiegénie mécaniqueingénierie de fabricationfabrication soustractive
- ingénierie et technologieingénierie des materiauxrevêtement et films
- sciences naturellessciences chimiqueschimie inorganiquemétalloïde
Vous devez vous identifier ou vous inscrire pour utiliser cette fonction
Thème(s)
Data not availableAppel à propositions
Data not availableRégime de financement
CSC - Cost-sharing contractsCoordinateur
42000 Saint-Étienne
France