含金属丝碳/碳复合材料的烧蚀产物

利用热化学理论及传热传质理论分析了碳/碳化金属/碳烧蚀机理;依据化学动力学中热力学参数与平衡常数关系得到烧蚀产物平衡常数与温度的简单关系式;在一定温度和压力条件下,根据化学反应式、平衡常数与分压关系式和组元浓度与分压关系式联合推导出封闭的烧蚀产物方程组,利用FORTRAN编程,求解得到烧蚀产物浓度和烧蚀速率与温度、压力的关系.计算结果表明含金属丝碳/碳复合材料在高温高压下,金属丝的氧化与碳的氧化相比可以略去,边界层内压力与温度共同决定烧蚀气体成分比例和烧蚀速度.

The Ablation Resultant of Carbon/Carbon Composites Embedded the Metal Fibre

The ablation property of Carbon/Carbon composite embedded the metal fibre is evaluated to determine the potential application this material in missile nose-tips. Firstly, the ablation mechanisms of thermal insulants are described in terms of both the thermochemistry and the molar transfer theory. Then, the equations of balanceable constant and temperature are obtained according to the thermodynamics parameter in the chemical dynamics theory. In the end, the ablation resultant equations, on the basis of which the ablation resultant thickness and ablation rate can be found utilizing FORTRAN program, are educed by using the parameter correlation of the chemical reaction, the balanceable constant, the part-pressure and the composition thickness. It is shown from the computational result that the oxidation of metal fibre in Carbon/Carbon composites may be ignored comparing with the oxidation of carbon, and the ablation resultant and ablation rate depend on both the pressure and the temperature in the boundary layer under the condition of high-temperature and high-pressure.