MgO /Cu composites with different MgO content such as 1%

3%

5%

8%

were prepared by SPS（ spark plasma sintering） method. Influences of different MgO volumetric fraction on density、electric conductivity

hardness and microstructure of the composites prepared were investigated. Arc erosion resistance was tested by JF04C electrical contact material testing system. Experimental results show that with the increase of MgO volumetric fraction

density and electric conductivity are decreased

meanwhile

the hardness is increased firstly and then decreased

and the weight loss is decreased and arc erosion resistance is improved. With MgO content of 5%

comprehensive properties of MgO /Cu composites exhibit desirable

where hardness is 110 HV and conductivity is 45. 24MS /m with electrical erosion resistance of 0. 1 mg. The microstructural observation reveals that with MgO content in range of 1% to 5%

MgO particles are uniformly distributed into the matrix with fine grain and decrease of contact surface melting degree. When the MgO volume fraction is 8%

MgO particles in copper matrix present a certain aggregation

leading to the comprehensive performance changes of MgO /Cu composites.