空气氧化处理对三维编织炭复合材料性能的影响

Effects of the air oxidation of carbon fibers on the properties of 3-D braided carbon/resin composites

利用真空浸渍法制得三维编织炭纤维增强环氧复合材料,研究了空气氧化处理前后炭纤维表面状态的变化以及表面处理对三维编织复合材料力学性能的影响。结果表明:空气氧化处理使炭纤维的比表面积和表面粗糙度发生了变化,随着氧化温度和氧化时间的增加,炭纤维的比表面积有不同程度的增加;但同时伴随着炭纤维强度的下降。经450℃-1h空气氧化处理后,复合材料的弯曲强度、弯曲模量和剪切强度分别提高了149%,91%和29%,但冲击强度下降了23%。

A three-dimensionally braided carbon fiber reinforced carbon/epoxy resin （C/Ep） composite was prepared by vacuum impregnation, and the effect of air oxidation of the fibers on the properties of the composite were investigated by SEM, nitrogen adsorption and mechanical testing. Results show that the specific surface area and surface roughness of the oxidized carbon fibers increase while their tensile strength decreases with increasing oxidation temperature or time. The flexural strength, flexural modulus, and shear strength of the C/Ep composites under the optimum treatment at 450 ℃ for 1 h were increased by 149 %, 91% and 29% respectively compared with the untreated samples, but the impact strength was decreased by 23 %.