球形氧化铝导热膏的制备及其导热性能

Preparation and Thermal Conductivity of Spherical Al_2O_3 Thermal Grease

以球形氧化铝为导热填料、二甲基硅油为基体,通过物理混合的方法制备了一系列氧化铝/硅油导热膏。通过增加氧化铝的添加量、加入硅烷偶联剂KH570以及粒径复配等提高导热膏的导热系数。用扫描电子显微镜（SEM）,对球形氧化铝进行形貌表征;用KD2Pro导热仪,对所制得的导热膏进行导热性能测试。结果表明：导热膏的导热系数随着氧化铝添加量的增大而增大,当氧化铝填充体积分数为60%最好;硅烷偶联剂KH570可以有效提高导热膏的导热系数,加入量（质量分数）在1.5%-2.5%时,效果良好;粒径的复配可以进一步提高导热膏的导热性能。

In this article,a series of thermal greases were prepared via physical milling method with spherical Al2O3 as filler and dimethyl silicone oil as matrix.The thermal conductivity of the thermal grease were improved by the amount of Al2O3 increasing,adding coupling agent KH570 and hybrids of different size.The Al2O3 was characterized with scanning electron microscope（SEM）.The thermal greases were measured by conductometer（KD2 Pro）.The result shows that thermal conductivity of the thermal grease increases with Al2O3 content increasing.KH570 can effectively improve the property of the thermal grease,and the best property can be obtained when the mass fraction KH570 is 1.5%—2.5%.Hybrids of different size can also improve thermal conductivity of thermal grease.