Cu-based and Cu-alloy-based diamond composites were made by high-pressure-high-temperature (HPHT) sintering with the aim of maximizing the thermal conductivity of the composites. Improvements in interfacial bonding ...Cu-based and Cu-alloy-based diamond composites were made by high-pressure-high-temperature (HPHT) sintering with the aim of maximizing the thermal conductivity of the composites. Improvements in interfacial bonding strength and thermo-physical properties of the composites were achieved using an atomized copper alloy with minor additions of Co, Cr, 13, and Ti. The thermal conductivity (TC) oh- mined exhibited as high as 688 W.m-1.K-1, but also as low as 325 W.m-1.K-l. A large variation in TC can be rationalized by the discrepancy of diamond-matrix interfacial bonding. It was found from fractography that preferential bonding between diamond and the Cu-alloy matrix occurred only on the diamond {100} faces. EDS analysis and Raman spectra suggested that selective interfacial bonding may be attributed to amorphous carbon increasing the wettability between diamond and the Cu-alloy matrix. Amorphous carbon was found to significantly affect the TC of the composite by interface modification.展开更多
基金supported by the National Natural Science Foundation of China (No.50971020) National High-Tech Research and Development Program of China (No.2008AA03Z505)
文摘Cu-based and Cu-alloy-based diamond composites were made by high-pressure-high-temperature (HPHT) sintering with the aim of maximizing the thermal conductivity of the composites. Improvements in interfacial bonding strength and thermo-physical properties of the composites were achieved using an atomized copper alloy with minor additions of Co, Cr, 13, and Ti. The thermal conductivity (TC) oh- mined exhibited as high as 688 W.m-1.K-1, but also as low as 325 W.m-1.K-l. A large variation in TC can be rationalized by the discrepancy of diamond-matrix interfacial bonding. It was found from fractography that preferential bonding between diamond and the Cu-alloy matrix occurred only on the diamond {100} faces. EDS analysis and Raman spectra suggested that selective interfacial bonding may be attributed to amorphous carbon increasing the wettability between diamond and the Cu-alloy matrix. Amorphous carbon was found to significantly affect the TC of the composite by interface modification.