Mechanical Properties of Cu-B/Diamond Composites Prepared by Gas Pressure Infiltration

Abstract

Diamond particles reinforced boron-alloyed Cu matrix (Cu-xB/diamond, x = 0.1, 0.2, 0.3, 0.4, 0.5, and 1.0 wt.%) composites were prepared by gas pressure infiltration. The size of the diamond particles was ~ 230 μm and the diamond volume fraction in the composites was ~ 66%. The interfacial carbide evolution plays an important role in improving the interfacial bonding and enhancing the mechanical properties of the Cu-B/diamond composites. The tensile, compressive and bending strengths firstly increase and then decrease with increasing boron content, giving a maximum tensile strength of 204 MPa, a maximum compressive strength of 608 MPa, and a maximum bending strength of 513 MPa at 0.5 wt.% B addition. The monotonic uniaxial tensile stress–strain curves of the Cu-B/diamond composites were predicted by using the Mori–Tanaka, generalized self-consistent, and Torquato identical hard spheres approximation models. The results suggest that alloying B to Cu matrix is an effective route to strengthening Cu/diamond composites.