Plasma deposition of elastic wear resistant Si–C coatings on nickel-titanium for biomedical applications

A bilayer system consisting of carbon and silicon has been developed to coat metals such as copper, stainless steel, nickel, and especially NiTi with an elastic, wear, and corrosion resistant film. The plasma deposited film system exhibits excellent adhesion on all metals under investigation. This adhesion is promoted by silicide formation. Additionally, the film system shows good performance under extremely high load induced via cavitation admission. Tensile tests reveal high elasticity of the film system, in that it can be elongated up to 5% before occurrence of damage of the film. The intrinsic stress inside this film system is reduced compared to pure diamondlike carbon films. Both good chemical bonding and reduced stress lead to good adhesion of the film systems on metals.