Microstructure and thermal behavior of diamond/Cu composites: Effects of surface modification

Copper matrix composites reinforced with dual-metal-layer coated diamond particles were prepared via hotpress sintering. The effects of W-Ni and W-Cu coatings on the microstructure and thermo-physical properties of the composites were analyzed. The thermal behavior of the composites was simulated using finite element models based on the experimental microstructure images. The results show that the dual-layer coatings not only favor the densification of the composites but also benefit the formation of excellent interfacial bonding. The thermal conductivity of the composites reinforced with 45 vol% W-Cu and W-Ni coated diamond particles reaches 661 and 563 W/mK, respectively. The simulation of the thermal behavior of the composites with dual layer coatings shows that a temperature drop occurs when heat flows through the boundary between the diamond and copper. The heat flux transmits from one diamond to the nearest one and forms a heat transfer channel along the direction of the temperature gradient.