Wear performance of C-W2B5 composite sliding against bearing steel

The C-W2B5 composite was fabricated by reaction hot-pressing of B4C and WC powders. The effect of applied load on the friction and wear behavior was investigated by the block-on-ring test in air. In particular, the composition and microstructural characterization of the mechanically mixed layers (MML) and wear debris formed during sliding wear were studied using scanning electron microscopy (SEM) with EDX and X-ray diffraction (XRD). The results revealed that the friction coefficients and wear rates of the composite increased with increasing testing load. The MML and wear debris generated from the sliding system had similar microstructural features and were composed of a mixture of ultrafine grained structures which mainly consisted of W2B5, Fe and Fe2O3. The formation mechanism of the MML and their influences on wear mechanism of the multiphase material were also studied on the basis of the microstructural observations.