新型炭材料2009，Vol.24Issue(2)：173-177,5.DOI:10.1016/S1872-5805(08)60046-3
高温热曝露对3D-C/SiC复合材料弯曲性能的影响
The influence of high temperature exposure to air on the damage to 3D-C/SiC composites
摘要
Abstract
3D-C/SiC composites, exposed in air at 600, 900, and 1 300 ℃ for 0 to 15 h, were investigated by three point bend tests at room temperature, SEM, and energy dispersive spectroscopy. The results show that the damage curves, expressed as a relative change of elastic modulus, of the composites for a 15h exposure, could be divided into a sharply increasing stage (stage Ⅰ) and a steady increasing stage ( stage Ⅱ). Stage Ⅰ may be caused by a direct oxidation of the carbon fibers and interface carbon layers by the oxygen in air, and stage Ⅱ may be caused by a diffuse controlled oxidation of the inner part of the composites. The matrix micro-cracks, induced by a difference of coefficients of thermal expansion between matrix and carbon fibers in the cooling process after composite preparation act as oxygen diffuse paths and are where the oxidation takes place. The fact that the damage decreases with temperature for the same exposure time may be caused by the crack shrinking at high temperature, which decreases the oxidizable surface area and inhibits the diffusion of oxygen into the composites.关键词
3D-C/SiC/热曝露/损伤/弯曲性能Key words
3D-C/SiC/Thermo-exposure/Damage/Flexural behaviors分类
通用工业技术引用本文复制引用
侯军涛,乔生儒,张程煜,张跃冰..高温热曝露对3D-C/SiC复合材料弯曲性能的影响[J].新型炭材料,2009,24(2):173-177,5.基金项目
国家重点实验室金属精密热加工基金,长江学者和创新团队发展计划项目资助.Foundation of National Key Laboratory for Precision Hot Processing of Metals and Program for Changjiang Scholars and Innova-tive Research Team in University （）
