THE INFLUENCE OF STACKING-FAULT ENERGY ON THE WEAR-RESISTANCE OF NICKEL-BASE ALLOYS

An effort has been made in the present investigation to correlate the deformation and sliding wear resistance of a series of nickel-cobalt a nd nickel-copper single phase, fee, solid-solution alloys with their s tacking fault energy (SFE) by conducting reciprocating sliding wear te sts against a diamond ball in ambient air. The surface damage has been characterized through scanning electron microscopy and X-ray photoele ctron spectroscopy. For the nickel-cobalt alloys the measured wear rat es were found to be mostly controlled by work-hardening and fatigue fr acture of the near surface region and a good correlation was obtained between the wear rates and the SFE of these alloys. The same trend has also been observed in nickel-copper alloys having less than 50 wt.% c opper. In higher alloy compositions, however, it was found that the in fluence of SFE on the wear rate is overshadowed by the beneficial lubr icating effect of build-up of copper oxides on the wearing alloy surfa ce. (C) 1997 Elsevier Science S.A.