Microstructure and Cutting Performance of TiB₂/ZL101 Composites Prepared by Direct Reaction Method

The TiB2/ZL101 composites were fabricated by direct reaction technique.The microstructure of composites was analyzed by means of optical microscoper,SEM and tensile tester.The mechanical properties and cutting performance of the composite were also tested.ZL101 alloy modified by Na-salt was compared with the composite.The results show that the microstructure of TiB2/ZL101 composite was fine equiaxed dendrities α-Al and fine plate-like eutectic silicon,the tensile strength was higher than that of ZL101 alloy,but the plasticity was opposite.Under the same cutting condition,the tool flank wear rate was close for cutting TiB2/ZL101 composite and ZL101 modified by Na-salt.The surface roughness of the composite was less than that of ZL101 modified by Na-salt.Two types of cracks were observed on the surface of cutting rod for TiB2/ZL101 composite.The second type of crack was harmful to the fatigue property of composite.