铜粉-石墨烯导热硅脂的制备及性能研究

摘要

研制高导热系数的导热硅脂是解决大功率电气、电子元器件散热问题的有效途径.本文以金属铜微米颗粒和改性石墨烯为导热填料制备导热硅脂.研究了不同粒径的金属铜颗粒级配比例以及改性石墨烯的填充量对导热硅脂的导热系数的影响规律,同时研究了所得导热硅脂的耐热稳定性.结果表明当小粒径铜粉占总铜粉体积的20%,并且改性石墨烯的质量分数为2%时,导热硅脂的导热系数为2.3 W/mK,是未添加石墨烯的导热硅脂的2.4倍,同时耐热稳定性完全符合国家标准的要求.研究结果显示了金属铜颗粒与改性石墨烯的协同作用,有利于高性能导热硅脂的设计和制造.%The development of thermal grease with high thermal conductivity is an effective way to solve the cooling problem of high power electrical and electronic components. In this work, thermal grease was prepared by usingmicron copper particles and modified graphene as conductive fillers. The influences of the ratio of copper particles with different sizes and the filling quantity of modified graphene on the thermal conductivity of the thermal grease werestudied. The thermal stability of the as-prepared thermal grease was also studied. The results indicate that the thermal conductivity of the thermal grease is 2.3 W/mK when the volume fraction of the small copper particles is 20% in the total volume of copper particles and mass fraction of the modified graphene is 2%. Such thermal conductivity is 2.4 times as high as the conductivity of the thermal grease without graphene. The thermal stability of the thermal grease completely meetsthe requirement of the national standard. The results of this study show that the copper particles and modified graphene have synergistic effect which is beneficial to the design and manufacture of high performance thermal grease.