WEAR BEHAVIORS OF LASER-CLAD STELLITE ALLOY-6

The wear behaviour of laser-clad stellite alloy 6 rubbed with AISI 414 0 and 4340 steels through a pin-on-disc wear test machine is studied. The stellite specimens were made from the product by laser surface cla dding of stellite alloy 6 powder on the mild and medium carbon steels, respectively, by a 3.3 kW continuous wave CO2 gas laser. The wear rat e of laser clad stellite alloy 6 under loads ranging from 9.8 N to 156 .8 N and sliding speed ranging from 1 m s(-1) to 4 m s(-1) is, in gene ral, quite mild, except thai under the load of 156.8 N and at the spee d of 4 m s(-1) the wear becomes a severe condition. Scanning electron microscopic examination of the worn surfaces shows that an oxide film was formed. X-ray diffraction analysis of the oxide film indicates tha t the oxides include W3O, Co2O3, Cr2O3, CrO and Cr5O12 depending on th e combined effect of sliding speed and normal load. The spalling of th e oxides is obviously a fatigue mechanism which controls the wear rate of the rubbing specimens. It can be shown that the oxides formed on s tellite alloy 6 are tougher than that formed on AISI 4140 and 4340 ste els.