Experimental Verification Of Tribological Properties Of Thin Coatings For Artificial Human Joints

Qualitative determination of tribological properties of thin coatings, with the aim to test them for possible modification of friction in tribological for artificial human joints system, was done. Experiments were done at common conditions of laboratory environment and temperatures. Attention was paid to tribological characteristics of coated materials suitable for implants of human joints. Unique test apparatus and advanced measurement techniques AFM for experimental procedures were involved. The plane samples for experiments consist of three types of microstructures of steel 100Cr6 obtained after heat treatment. Samples with martensitic, bainitic, and sorbitic structure were coated with a hard and wear resistance WC/C coating. The coatings were deposited to functional surfaces of all plane samples. Magnetron sputtering method was used. As second friction body, a standard ball made of steel 100Cr6 was chosen. Received results extend the existing knowledge of tribology of thin layers. The friction processes in systems with high contact loads and the surface topography, using AFM microscope, were evaluated. The minimum friction coefficient values reached the level of 0.1-0.15; those are approximately 10 times higher as these for natural human joints. The lowest value of coefficient of friction was reached for WC/C coated samples with bainitic structure of the substrate.