LUBRICATED ROLLING AND SLIDING WEAR OF A SIC-WHISKER-REINFORCED SI3N4 COMPOSITE AGAINST M2 TOOL STEEL

Mineral oil lubricated rolling and sliding wear of SiC whisker (SiC(W)) reinforced Si3N4 composite and monolithic Si3N4 prepared identically against M2 tool steel were investigated using a cylinder-on-cylinder apparatus. Wear of this Si3N4 was higher than that of the composite. Wear of the steel against Si3N4 was also higher than that against the composite. Relatively larger scale microfracture occurred in the Si3N4 than in the composite; more pullout and microchipping of carbide particles were observed in the steel against Si3N4 than against the composite. Polishing of the worn surfaces of the steel occurred in both sliding and rolling tests. This was attributed to fine, hard wear debris circulating in the contact area. Spalling was observed in the steel sliding against Si3N4 but not in the steel sliding against the composite.