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采用热压烧结工艺制备了 Ti Cp/ W系列复合材料 ,分析测试了温度和 Ti C含量对复合材料的热物理性能的影响规律。结果表明 :随着温度的升高 ,复合材料的定压比热和平均线膨胀系数单调增大 ,热扩散率稍有减小 ,热导率略有增大。随 Ti C含量的增加 ,复合材料的定压比热和平均线膨胀系数线性增大 ,基本满足混合定律。热扩散率和热导率对材料的组织结构比较敏感 ,二者均随 Ti C含量的增加而急剧减小。热导率的实测值大大低于理论计算值 ,这主要是由晶界和孔洞等缺陷对导热粒子的强烈散射作用造成的。
The Ti Cp / W series composites were prepared by hot-pressing sintering process. The influence of temperature and Ti C content on the thermophysical properties of the composites was analyzed. The results show that with the increase of temperature, the specific heat at constant pressure and average linear expansion coefficient of monolithic composite increase monotonously, the thermal diffusivity decreases slightly and the thermal conductivity increases slightly. With the increase of TiC content, the specific heat at constant pressure and the average linear expansion coefficient of the composites increase linearly, basically meeting the mixing law. Thermal diffusivity and thermal conductivity are more sensitive to the microstructure of the material, both of which decrease drastically with increasing Ti content. The measured values of the thermal conductivity are much lower than the theoretical values, mainly due to the strong scattering effect of the defects such as grain boundaries and voids on the thermal conductive particles.