TKACHENKO Sergey Brno University of Technology

Spoluautoři DATSKEVICH Oleg, KULAK Leonid, PERSSON Cecilia, ENGQVIST Håkan

Titanium alloys are commonly used as implant materials in medicine due to remarkable combination of high mechanical properties, good biocompatibility and enhanced corrosion resistance. However, their broader use is somewhat limited by poor tribological properties. Our previous studies showed that the complex alloying with Si and Zr in combination with strengthening heat treatment offer a promising way to significantly increase hardness and wear resistance of titanium. In present study the tribological performance of experimental Ti-Si-Zr alloys has been determined as compared to that of the standard Ti-6Al-4V, CoCr F75 and CoCr F799 alloys. The friction and wear tests were performed by using a standard ball-on-disc rig in serum solution at ambient temperature with Si3N4-balls as counter-bodies. Measurements of friction coefficients and volumetric wear rate were made and microscopic investigations of the wear tracks were performed along with examination of alloys structure and properties using an optical microscope, XRD, SEM and hardness testing. The minimal value of coefficient of friction among all studied materials was demonstrated by the hypo-eutectic Ti-6Si-5Zr alloy. The wear rates of the Ti-Si-Zr alloys were found to be about 2-6 times higher than that of standard Ti-6Al-4V alloy. Friction results and morphology of worn surfaces showed that tribological properties are determined to the predominant wear mechanism, which for Ti-Si-Zr alloys and Ti-6Al-4V was primarily adhesive, while for both CoCr alloys it was abrasive.