| Abstract: | The fretting wear behaviour of bearing steel against bearing steel, silicon nitride against silicon nitride, and silicon nitride against bearing steel, was investigated under lubricated and dry conditions. Amplitudes in the intermediate 5 to 50 μm range, and test durations from 10 to 360 min, were studied. Light microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) were employed to determine the detailed nature of the friction and wear processes. In the silicon nitride against silicon nitride contact, brittle fracture of Si3N4 grains, and tribochemical reaction creating an amorphous layer on the mechanically damaged surface, were found. The main mechanism of fretting wear in the case of bearing steel against bearing steel contact was delamination. In the silicon nitride against bearing steel contact, chemical reactions predominated. |
