Microstructure, electrical, and tribological properties of copper matrix composites reinforced from dual-scale boride ceramic particles

Wear is an inevitable issue for mechanical equipment, leading to increased failure rates and reduced service life. Copper (Cu) and its alloys exhibit high electrical and thermal conductivities; however, the insufficient hardness and poor wear resistance limit their application in electronic and electrical engineering. To address the incompatibility between electrical conductivity and tribological properties in Cu materials, dual-scale TiB₂ ceramic particles were used to reinforce Cu matrix composites, which were fabricated via spark plasma sintering. The effect of TiB₂ content on the microstructure, hardness, electrical conductivity, and wear resistance of the TiB₂/Cu composites was investigated. The results indicated that the TiB₂ ceramic particles were well dispersed within the Cu matrix. The hardness of the composites was significantly improved without a substantial reduction in electrical conductivity. Additionally, the compressive strength and wear resistance of the Cu-based composites were enhanced by the addition of dual-scale TiB₂ ceramics. The wear resistance of the composite with 15 wt% TiB₂ was 3.06 times higher than that of the composite with 5 wt% TiB₂ under an applied load of 20 N. The dominant wear mechanisms of the composites were adhesive wear, oxidation wear, and abrasive wear.