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The (Cu-50Mo)-0.5%LaCl₃ and (Cu-50Mo)-5%WC-0.5%LaCl₃ composites were prepared by spark plasma sintering (SPS) process. The density, hardness, electrical conductivity and microstructure of the composites were investigated respectively. The electrical contact test was carried out for both composites. The materials transfer direction and the anode, cathode mass change and the contact ends total mass change of the composites were studied under the condition of different DC and resistance load respectively. The morphologies after arc erosion were investigated by means of scanning electronic microscopy (SEM). The electrical erosive characteristics of the composites were analyzed. The results show that the composites have better comprehensive properties prepared by SPS method. The transfer mass increases with increase of electrical current density. The contact surface of the composites present the appearance characteristics with pores、molten pool and pits after arc erosion test. The surface arc erosion characteristics are much more obvious with increasing of current density. The contact resistance decreases with increasing of current. The contact resistance with the current changes has no obvious fluctuation, while the welding force increases with increase of current.