Effect of Hot-Pressing Pressure on the Microstructure and Thermal Conductivity of Copper/Ti-Coated Diamond Composites

Abstract

Copper/diamond composites show promise as potential thermal management materials for electronic devices due to their excellent thermophysical properties. In this study, copper/55vol%Ti-coated diamond composites were fabricated by hot pressing at 800oC and varying pressures of 300MPa, 400MPa, 500MPa, and 685MPa. The results illustrated that the thermal conductivity of the copper/Ti-coated diamond composites initially increased and then decreased as the pressing pressure increased. Among these hot-pressed composites, the composite hot-pressed at 500MPa exhibits the highest thermal conductivity of 466W/mK. This is attributed to the uniform diamond distribution, highly covered TiC interface on the diamond, and the strong interfacial bonding between the copper and the diamond. Hot pressing is a feasible alternative to fabricate copper/diamond composites with high relative density and high thermal conductivity, the pressing pressure plays a vital role in the microstructure and the final properties of the copper/Ti-coated diamond composites.