DRY SLIDING WEAR BEHAVIOUR AND MICROSTRUCTURE OF THE W–Ni–Fe AND W–Ni–Cu HEAVY ALLOYS PRODUCED BY POWDER METALLURGY TECHNIQUE

Abstract

The effects of Fe and Cu on the wear behaviour of W–Ni alloys is investigated. W–Ni–Fe and W–Ni–Cu alloys are produced with six different compositions by the powder metallurgy technique. The microstructure is examined after shaping and sintering. Electron microscopy (SEM+EDS) and X-ray diffraction (XRD) are used to characterize the density, hardness, and grain size of W–Ni–Fe and W–Ni–Cu alloys produced by powder metallurgy technique. A pin-on-disc apparatus is used for the wear tests. All of the samples are tested under loads of 20 and 30 N, at a rate of 1 m/s and for five different sliding distances. It is found that, in Fe and Cu alloys, an increase in the W amount results in an increase in density and hardness. Furthermore, an increase in the W amount leads to a decrease in the amount of the binding phase for W–Ni–Fe and W–Ni–Cu alloys with a W content of 90, 93, and 97%, and resultes in reduced weight loss for W–Ni–Fe alloys.