微球型炭泡沫复合材料力学性能的研究

为表征微球含量对碳泡沫复合材料的影响，以自制热固性酚醛树脂与不同体积分数的酚醛空心微球配比混合，采用模压成型法，制备酚醛泡沫材料；再将其在Ar气保护下高温碳化处理，得到微球型碳泡沫复合材料；研究碳泡沫复合材料的微观结构及空心微球的体积分数对碳泡沫的压缩性能、断裂韧性的影响。结果表明：随着空心微球含量的增加，复合材料的压缩断裂特征由梯度式脆性断裂模式向假塑性断裂模式转变，其断裂韧性也得到了明显改善；空心微球含量为80v01．％的碳泡沫韧性最佳；适当提高空心微球含量，可改善碳泡沫的比压缩强度，空心微球含量为70v01．％的碳泡沫的比压缩强度可达43．32MPa·cm3·g-1。

Mechanical properties of carbon foam composites containing hollow micropheres

Phenolic foams were prepared by compression molding mixng phenolic resin with hollow phenolic microspheres by different volume ratio, followed by carbonizing at 900 °C under Ar to produce carbon foams composites with hollow carbon microsphere structure. Microstructure of carbon foams were studied. Effect of content of microspheres on compressive properties and fracture toughness of carbon foams were investigated. The results show that compressive fracture characteristics of carbon foams change from gradient-brittle fracture to pseudoplastic with increasing content of microspheres, fracture toughness of which obviously improved for same change. Fracture toughness of CF-80 performs better than others. The specific compressive strength of carbon foams could be improved by increasing content of microspheres properly, and that of CF-70 is up to 43.32 MJ.kg_-1.