C/C复合材料比热容和热扩散率的研究

Research on Thermal Diffusivity and Specific Heat Capacity of C/C Composites

研究了C/C复合材料的比热容、热扩散率及其影响因素。研究表明,C/C复合材料的比热容随着温度的升高而增大,在1 300 K时比热容达到最大值1.8 kJ/(kg.K),之后随着温度的升高,比热容保持恒定;C/C复合材料的热扩散率随着温度的升高而降低,碳纤维的取向与热传导方向一致时热扩散率最高;石墨化度高,热扩散率高;C/C复合材料的热扩散率随着材料密度的增加而增大。

Major factors affecting the thermal diffusivity and specific heat capacity of C/C composites are discussed,which shows that the specific heat capacity is increased with increasing of the temperature at the beginning while it reaches the maximum value of 1.8 k J/（ kg· K） at 1 300 K and then keeps constant. On the contrary, the thermal diffusivity of C/C composites is decreased with increasing of the temperature. C/C composites have high thermal diffusivity along the orientation of carbon fiber. The higher the graphitization degree of C/C composites, the higher the thermal diffusivity. Meanwhile, the thermal diffusivity of C/C composites is increased with increasing of its density.