An analysis of microstructure and property of cerium dioxide incorporated in tungsten-copper composites prepared by activation sintering method

A series of W–Cu–Co-xCeO2 composites were obtained through activation sintering method, and their microstructure and properties were systematically researched. As the amount of CeO2 increased, the size of W particle in composites showed a decreasing trend as a whole. When the CeO2 amount was 0∼0.8 wt%, the W particles in composites exhibited a large size and dense distribution. As the CeO2 amount further increased, the size of W particle began to significantly decrease and the distribution area of Cu phase was uneven. The porosity of W–Cu–Co-xCeO2 composites first decreased and then increased. The density, relative density, and hardness exhibited an opposite trend. When the CeO2 amount was 0.8 wt%, these values reached their maximum values of 14.16 g/cm3, 98.66%, and 223 HV3.0, respectively. In addition, the friction coefficient (COF) and wear rate of W–Cu–Co-xCeO2 composites first decreased and then increased, which reached the lowest values at CeO2 of 0.8 wt%. At this time, the COF and wear rate were about 0.356 and 5.78 × 10−6 mm3/Nm, respectively.