Effect of rare earth Ce on the microstructure and properties of Cu-Al₂O₃ composites

The Cu-Al₂O₃-Ce composites doped with rare earth Ce in different mass fractions were fabricated by mechanical alloying and spark plasma sintering. The effect of Ce content on the microstructure and physical properties of Cu-Al₂O₃ composites were studied. The results show that, the ceramic particles are uniformly dispersed in Cu-Al₂O₃-Ce composites. Compared with Cu-Al₂O₃ composites, the Cu-Al₂O₃-Ce composites performances are significantly improved, having the hardness of HV 108.2, the tensile strength of 301 MPa, the elongation of 19.6%, and the conductivity of 54.51 MS·m^-1. The wear mechanism of Cu-Al₂O₃ and Cu-Al₂O₃-Ce is abrasive wear and adhesive wear, respectively. Compared with Cu-Al₂O₃ composites, Cu-Al₂O₃-Ce composites have the smaller friction coefficient and volume abrasion rate at high friction rate. Thus, the wear resistance of Cu-Al₂O₃-Ce composites is highly improved by doped with rare earth Ce.