Fretting wear study of Cu–10 wt% TiB2 and Cu–10 wt% TiB2–10 wt% Pb composites

In developing materials with better tribological properties, it is always conceived that the addition of softer phase would result in better frictional behavior. In order to address this issue, we report here the results of fretting wear study on Cu–10 wt% TiB2 and Cu–10 wt% TiB2–10 wt% Pb composites, sintered using spark plasma sintering (SPS) technique. It was found out that the addition of softer phase i.e. 10 wt% Pb to Cu–10 wt% TiB2 composites has not resulted in the lowering of the coefficient of friction (COF). The combination of steady state COF (0.6) and wear rate (10−3 mm3/N-m) was measured and such properties are even better than that obtained with TiB2 coatings reported in the literature. For Cu–10 wt% TiB2 sintered at different temperature, a lower wear resistance with increase in hardness is being measured. An attempt has been made to correlate the observed wear behavior with the surface and subsurface deformation. The formation of a wear-resistant delaminated tribolayer consisting of TiB2 particles and ultrafine oxide debris (Cu, Fe, Ti)xOy was the reason assigned for the observed low wear rate of these composites.