Wear Behaviors of MoSi2 Mated with Different Materials at High Temperature

The friction and wear properties of molybdenum dislicide (MoSi2) against Al2O3, SiC and Si3N4 at different sliding speeds at 1000?C in air were investigated on an XP-5 type high temperaturefriction and wear tester. Morphologies and phase compositions of the worn surfaces of MoSi2 and its counter-face materials were observed by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Results showed that friction coefficient and wear rate of MoSi2 decreased with the increase of sliding speed and SiC was a suitable counter-face material of MoSi2 at high temperature. Adhesion and oxidation were the main wear mechanisms of MoSi2 sliding against Al2O3,. However against SiC and Si3N4, abrasion, mild oxidation and pitting became the main wear mechanisms of MoSi2.