FRETTING CORROSION STUDIES OF MATERIALS USED FOR ELEMENTS OF HIP JOINT ENDOPROSTHESES

摘要

The operational durability of a hip endoprosthesis depends, among others, on the intensity of the damage processes of kinematic junction elements caused by fretting corrosion processes. In the article, the results of comparative studies on the fretting corrosion resistance of alloys commonly used for hip joints, i.e. Ti_6Al_4V, CoCrMo, stainless steel M30NW, and 316LVM, are presented. The research was carried out by means of a tribological pin-on-disc tester working in reciprocating motion, integrated with a potentiostat equipped with a triac electrode. The tribosystem was a pin pressed by a constant force to a reciprocating disc with a certain amplitude and frequency. The tests were carried out in a medium of aqueous bovine serum heated to 37°C. The conducted comparative tests of the above mentioned materials will allow selection of the best material combination in terms of tribological and fretting corrosion resistance. Under optimized conditions, the modified oils obtained a needed appropriate viscosity class.