Preparation of high thermal conductivity diamond/Cu–B alloy composites by gas pressure infiltration method

Abstract

The Cu–B alloy with boron mass fraction of 0.5% was used as the metal matrix, and the diamond with an average particle size of 500 μm was used as reinforcement, the diamond/Cu–B alloy composites were prepared by gas pressure infiltration method. The effects of gas pressure parameters on the microstructures and the thermophysical properties of the composites were studied. The results show that the interfacial bonding effect and the thermal conductivity between diamond and Cu–B alloy are enhanced and the thermal expansion coefficient is reduced with the increase of gas pressure. When the gas pressure is 10 MPa, the interfacial bonding effect is the best. The carbide layer formed at the interface completely covers the diamond, the thermal conductivity of the sample at 100 ℃ is 680.3 W/(m·K), and the thermal expansion coefficient is 5.038×10−6 K−1, which meets the thermal expansion coefficient requirements of electronic packaging materials.

Keywords

• thermal conductivity
• gas pressure infiltration method(gpi)
• diamond/cu–b composite material; thermal expansion coefficient