Dry sliding wear of Ni alloyed austempered ductile iron

Abstract

Measurements of dry sliding wear are presented for ductile irons with composition Fe-3.56C-2.67Si- 0.25Mo-0.5Cu and Ni contents of 0.8 and 1.5 in wt.% with applied loads of 50,100 and 150 N for austempering temperatures of 270,320,and 370 °C after austenitizing at 870 °C for 120 min. The mechanical property measurements show that the grades of the ASTM 897M: 1990 Standard can be satisfied for the selected austempering conditions. The results show that wear resistance is independent of austempering temperature with an applied load of 50 N,but there is a strong dependence at higher austempering temperatures with applied loads of 100 and 150 N. Observations indicate that wear is due to subsurface fatigue with cracks nucleated at deformed graphite nodules.