真空蒸镀钨改性金刚石/铜硼复合材料导热性能

Thermal conductivity of tungsten modified diamond/copper-boron composites by vacuum vapor deposition

采用真空蒸镀法在平板金刚石衬底表面镀覆钨镀层,构建多层平板结构以研究热处理温度对金刚石表面钨界面层形貌结构、物相成分及其与金刚石基体间界面结合情况的影响,并为金刚石颗粒表面金属化改性提供实验指导。在此基础上,以相同真空蒸镀和热处理工艺制备的钨改性金刚石颗粒作为增强体,以铜硼合金作为基体,采用气体压力浸渗法制备相应的金刚石/铜硼复合材料,探究金刚石颗粒的热处理温度对复合材料导热性能的影响。结果表明:随着热处理温度的升高,复合材料热导率呈现先上升后下降的趋势,当热处理温度为1000℃时,复合材料界面结合明显改善,同时金刚石表面钨镀层依旧连续完整,此时,复合材料的热导率最高可达629 W/(m∙K)。

The tungsten(W)coating was plated on the flat diamond substrate using the vacuum evaporation method.A double-layer flat structure,consisting of W and diamond,was constructed to investigate the effects of heat treatment temperature on the morphology,phase composition and interfacial bonding of W coating on the diamond surface,which is to offer experimental insight into the surface metallization of the diamond particles.Subsequently,the diamond particles modified with tungsten,prepared by the same vacuum vapor deposition process were used as reinforcement.A matrix of copper-boron alloy was employed,and diamond/copper-boron composites were prepared by gas pressure infiltration method.The impact of the heat treatment temperature of diamond particles on the thermal conductivity of the composites was investigated.The results show that,with the heat treatment temperature increasing,the thermal conductivity of the composite first increases,and then decreases.When the heat treatment temperature is 1000℃,the interfacial bonding of the composites significantly improves while the W coating remains continuous and intact,resulting in thermal conductivity up to 629 W/(m∙K).