ION-IMPLANTATION AND THERMAL-OXIDATION AS TREATMENTS TO INITIATE SUSTAINED OXIDE WEAR IN STEELS

Both nitrogen implantation (2.5×1017 N+2 /cm2 at 180 keV) and low-temperature (?315 °C) oxidation are shown to produce an order of magnitude reduction in the wear rate of an SAE 3135 steel. Measurements of the wear rates, wear member asymmetry behavior, and both scanning electron microscopy and Auger studies indicate that the same mechanism leads to the much improved wear rates. Both treatments substantiate the initiator/sustainer wear model, in which the initiation treatment reduces the wear to a low value that is sustained throughout the wear test. The sustained stage is a form of mild wear, which involves oxygen and appears to be oxidative wear.