Effect of La₂O₃ on the microstructure and properties of CuW electrical contact materials

W powders with rare earth oxide La₂O₃ were prepared by liquid-solid blending method, which includes mixing La(NO₃)₃ and WO₃, drying, decomposition of La(NO₃)₃ and reduction of WO₃. CuW electrical contact materials with La₂O₃ were fabricated by powder metallurgy-infiltration technology. The effect of holding time on the revivification of La(NO₃)₃ and that of La₂O₃ addition on the properties of CuW electric contact materials were investigated. The results show that La₂O₃ distributes uniformly in fine tungsten compound powders, and the particle size of powders decomposed by La(NO₃)₃ increases with prolonging holding time. The electrical breakdown strength of CuW electrical contact materials doped with La₂O₃ increases significantly.