Understanding on the Correlation between Mechanical Properties and Thermal Conductivity of Hot-Forged Copper/Diamond Composites

Abstract

Evaluation of the mechanical properties of copper/diamond composites is necessary for understanding the interfacial bonding, which is important for the interface thermal conductance and thermal conductivity of the composites. The tensile and three-point bending tests are conducted on the hot-forged copper/diamond composites using Cr powder additives and Cr-coated diamond. The interfacial bonding strength of the composites is calculated and evaluated based on the tensile results. The fracture mechanisms of the fabricated copper/diamond composites are discussed and compared. The highest tensile strength (69 MPa) and interface bonding strength (0.043 J m⁻²) are achieved for the Cu–3Cr-55vol% diamond composite hot-forged under 1050 °C. The connection between the composite's interfacial bonding strength and its thermal conductivity is elaborated.