| Summary: | In this paper, boron carbide (B<sub>4</sub>C) ceramics were added to a copper (Cu) base, to improve the mechanical properties and wear resistance of pure copper. The B<sub>4</sub>C/Cu composites with different B<sub>4</sub>C contents, were obtained by mechanical mixing and discharge plasma sintering methods. Scanning electron microscopy (SEM), energy spectrum analysis (EDS), and electron probe microanalysis (EPMA) were used, to observe and analyze the microstructures of the B<sub>4</sub>C/Cu composites. The influences of the B<sub>4</sub>C content on the hardness, density, conductivity, and wear resistance were also studied. The experimental results show that B<sub>4</sub>C has an important effect on Cu. With increasing B<sub>4</sub>C content, both the density and conductivity of the B<sub>4</sub>C/Cu composites gradually decrease. The hardness of the Cu-15 wt.% B<sub>4</sub>C composite has the highest value, 86 HBW (Brinell hardness tungsten carbide ball indenter), which is 79.2% higher than that of pure copper. However, when the B<sub>4</sub>C amount increases to 20 wt.%, the hardness decreases due to the metallic connection being weakened in the material. The Cu-15 wt.% B<sub>4</sub>C composite has the lowest volume loss, indicating that it has the best wear resistance. Analyses of worn B<sub>4</sub>C/Cu composite surfaces suggest that deep and narrow grooves, as well as sharp ridges, appear on the worn pure Cu surface, but on the worn Cu-15 wt.% B<sub>4</sub>C composite surface, the furrows become shallow and few. In particular, ridge formation cannot be found on the worn Cu-15 wt.% B<sub>4</sub>C composite surface, which represents the enhancement in wear resistance.
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