AlN/MAS微晶玻璃复合材料的热物理性能

Thermophysical properties of AlN/MAS glass-ceramic composites

通过X射线衍射、扫描电镜和热物理性能测试,研究AlN引入量和温度对在900～1000℃真空热压烧结制备的AlN/MAS玻璃陶瓷复合材料热物理性能的影响。研究结果表明:复合材料的热膨胀系数随着AlN引入量和测试温度的增加而增加;热导率随着AlN引入量的增加而增加;随着测试温度的升高,复合材料的热导率随着AlN引入量的变化呈现不同的特征;AlN引入量为20%(体积分数)时,样品的热导率随着测试温度的升高而升高,表现出明显的非晶态物质的导热特性;AlN引入量为50%时,样品的热导率呈现先升高后稍许降低的导热特性。

The effects of AlN content and temperature on thermophysical properties of AlN/MAS（MgO-Al2O3-SiO2 system）glass-ceramic composites fabricated by hot-press sintering in vacuum at 900-1 000 ℃ were investigated by means of X-ray diffractometry, scanning electron microscopy and thermophysical property measurement. The results show that the thermal expansion coefficient of the composites increases with the increase of AIN content and testing temperature, and the thermal conductivity of the composites increases with the increase of AIN content. As testing temperature rises, the thermal conductivity of the composites exhibits a different behavior with the increase of AlN content. The thermal conductivity of the composite containing 20%（volume fraction） AlN content enhances with the increase of testing temperature, which exhibits clearly the conductivity behavior of non-crystalline solids. However, the thermal conductivity of the composite containing 50% AlN firstly increases and then slightly decreases.