Mechanical Properties of ta-C Films Deposited on Polyethylene and Metallic Substrates

Research in the area of advanced materials application in artificial prosthetics with a view to minimize the biochemical and mechanical complications of implanted materials is carried out. In this paper the results of physical chemical characterization, mechanical properties (nano-hardness, elastic modulus) and tribological testes of ta-C films deposited on ultra high molecular weight polyethylene (UHMWPE) and metallic substrates (Ti, Co-Cr- Mo, stainless steel 138F, hard alloy) are presented. These films were obtained by pulsed arc plasma method (physical vapour deposition, PVD) using a carbon source accelerator in a vacuum of 2 x 10(exp -4) Pa. Physical chemical characterization of ta-C films had been carried out by different methods. The nano-hardness and elastic modulus of ta-C films (approximately 250 nanometers) deposited on the metallic and UHMWPE substrates were measured by nanoindentation method. It was determined that the nano-hardness and elastic modulus are larger for ta-C deposited on the metallic substrates than that deposited on UHMWPE. Wear resistance and the coefficient of friction of ta-C film were measured by different methods.