Study On Microwave Sintering Process Of Diamond Surface Metallization And Diamond / Copper Composites

Diamond reinforced copper matrix composites combining the advantages of diamond and copper has a high thermal conductivity, thermal expansion coefficient and adjustable lower density, which will meet the cooling requirements of electronic components. Therefore, it has important theoretical and practical value for the research of diamond reinforced copper matrix composites.However, diamond is a non-metallic material has a high interfacial energy, which can not effectively wetted with the metal or alloy, and also the thermal expansion coefficient of diamond is much smaller than the thermal expansion coefficient of the metal binding agent. In this study, the microwave heating method in synthetic diamond surface pre-plated with a layer of chromium under the conditions of microwave heating.By adjusting the holding time and the heating temperature control the thickness of the diamond surface coating. Microwave is heated from 750 ℃ to 900 ℃, incubated at 1h conditions, the coating thickness from 0.73μm to 2.30 μm. Heating temperature of 850 ℃, holding time was from 0.5h to 4h conditions, the coating thickness from 1.30μm to 2.80μm. By comparing the traditional box-type resistance furnace heating and microwave heating that the traditional box-type resistance furnace heated to 850 ℃ takes about three hours, the temperature was raised to 850 ℃ heating only half an hour, greatly reducing the chrome cycle, improve the efficiency of chrome.Respectively microwave sintering powder metallurgy and microwave heat-press powder metallurgy sintering the diamond surface modified reinforced copper matrix composites. Using scanning electron microscopy studied composite microstructure, using Archimedes method tested different pressures and different green diamond composite volume fraction density, the use of thermal conductivity tester to study thermal conductivity of composite materials.The results:surface modified diamond particles dispersed in the copper grains. The effects of different pressures and different green diamond volume fraction of diamond to the composite material density, and found that with the increasing pressure, the density of composite material increasing, with the increasing volume fraction of diamond composites induced density decreased. Microwave no pressure sintered diamond/copper composite diamond when the volume fraction of 40%, the highest thermal conductivity of 113.71W / (m·K). Microwave Sintering diamond/copper composite material, with the increase in pressing pressure, thermal conductivity diamond/copper composite material from 88.35W/(m·K) to 156.17W/(m·K), than the microwave sintering the thermal conductivity of the composites increased. Show some advantages for further in-depth study has important significance. which show some advantages,which is important significance for further in-depth study.