C/C复合材料高温热物理性能实验研究

实验研究了烧蚀防热C／C复合材料从常温到高温的等效热膨胀系数、热扩散率、比热随温度的变化情况，并计算了材料不同温度下的热导率与抗热应力系数。结果表明：材料的热膨胀系数很小，接近零膨胀。热扩散率随温度升高而下降，比热随温度升高近似比例增加，而热导率随温度的变化规律与热扩散率相似。材料的抗热应力系数随温度的升高变化不大，抗热震性能稳定。

An experimental study on thermophysical properties of C/C composites at elevated temperature

In present paper,coefficient of thermal expansion,thermal diffusivity and specific heat of ablation thermal protective composites C/C composites from room temperature to ultra high temperature have been experimentally investigated.Thermal conductivity and thermal stress resistance of the composite are therefore computed based on experimental results.The results show that the composite has a very low thermal expansion coefficient,near zero.Thermal diffusivity decreases exponentially with increasing temperature.The specific heat increases linearty with temperature.And thermal conductivity has a similar variety as thermal diffusivity.Thermal stress resistance has a little change with temperature,the thermal stress resistance of the composite keeps stable.