DEPOSITION OF TiN COATINGS USING CAPVD TECHNIQUE ON AM60 ALLOY

Magnesium alloys are of special interest due to their good specific properties, low cost and good manufactured properties. However, their low hardness, wear and corrosion resistance limit their applications in certain industrial sectors. These drawbacks can be solved by applying hard ceramic coatings, such as nitrides or metal carbides. TiN is one of the most used coatings due to its high adhesion, hardness, low coefficient of friction and chemical stability. Physical vapour deposition by cathodic arc (CAPVD) is a versatile technique, which uses low temperatures and high ionisation energies, generating homogeneous coatings. To achieve high quality coatings, careful control of the production parameters, such as bias voltage, gas flow or intensity, is required. AM60 magnesium alloys were coated with TiN using the CAPVD technique at different intensity values (40 A and 100 A) and surface preparation (grinding up to 4000 grit and polished to 3 micron). An intermediate Al film was included. The samples were characterised by XRD, surface roughness measurements, and microstructural analyses.