轴棒法编织C/C复合材料的热物理及烧蚀性能  

Thermophysical and ablative properties of axial carbon rod weaved 4D carbon/carbon composites

作　　者：曹翠微[1] 李照谦[1] 李贺军[1] 李克智[1] 付前刚[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室C/C复合材料工程技术研究中心,西安710072

出　　处：《固体火箭技术》2011年第1期113-118,共6页Journal of Solid Rocket Technology

基　　金：国家自然科学基金项目(50832004);西北工业大学基础研究基金(W018109)

摘　　要：采用轴棒法编织三维四向炭纤维预制体,经高压沥青浸渍炭化致密化工艺(HIPIC)制得高密度4D C/C复合材料,研究了材料轴向的热物理性能、抗烧蚀性能,并分析了材料的烧蚀机理。结果表明,轴棒法编织C/C复合材料轴向的热扩散率随着温度的升高而降低,比定压热容随温度的升高而增大,热导率随温度的升高缓慢下降,且材料的热物理性能在高温时趋于稳定;材料轴向具有较低的热膨胀系数,热膨胀系数随温度的升高而增大,在较低温度时具有负热膨胀行为;材料轴向具有较优异的抗烧蚀性能,经120 s氧-乙炔烧蚀后的质量烧蚀率和线烧蚀率分别为2.04×10-3g.s-1和3.92×10-3mm.s-1,烧蚀过程主要受热化学烧蚀和机械剥蚀共同作用。A kind of high-density C/C composite reinforced by carbon fiber and axial carbon rod mix weaved 4D perform was prepared by the process of high-pressure pitch impregnation and carbonization.The thermophysical and ablative properties of the 4D C/C composites in axial direction were investigated.The results show that with increasing temperature the thermal diffusivity of the composites decreases exponentially,the specific heat increases,and the thermal conductivity decreases linearly,and the thermal constants will tend to steadily at high temperature.The 4D C/C composites exhibit a negative coefficient of thermal expansion at low temperature,which increases with increasing temperature.After 120 s oxygen-ethyne ablation,the mass ablation rate and linear ablation rate is 2.04×10^-3g·s^-1 and 3.92×10^-3mm·s^-1,respectively.The ablation mechanism of the 4D C/C composites is mainly a synergistic effect of thermo-chemical ablation and mechanical erosion.

关 键 词：C/C复合材料 热导率 热膨胀系数 烧蚀性能 

分 类 号：V258[一般工业技术—材料科学与工程]