Wear characteristics of phosphor–bronze/silicon carbide particulate composites

The tribological properties of metal matrix composites (MMCs) is of interest in several applications like bearing sleeves, piston and cylinder liners, aircraft brakes, etc. The wear behavior of unreinforced as well as SiC particles reinforced phosphor–bronze alloy composite materials is studied as a function of sliding speed and applied loads under unlubricated conditions. The content of SiC particles in the composites was varied from 1 to 5% in steps of 2% by weight. A pin-on-disc wear testing machine was used to evaluate the wear rate, in which EN24 steel disc was used as the counterface. Loads of 20–160 N in steps of 20 N and speeds of 1.25, 1.56 and 1.87 m/s was employed. The results indicated that the wear rate of both the composites and the matrix alloy increased with increase in load and sliding speed. However, the composites exhibited lower wear rate than the alloys. It was found that above a critical applied load, there exists a transition from mild to severe wear both in the unreinforced alloy and in the composites. But the transition loads for the composites were much higher than that of the unreinforced alloy. The transition loads increased with the increase in weight percent of SiC particles, but decrease with the increase in sliding speeds.