摘要
以液化气为碳源前驱体,氮气为稀释气体,采用定向脉冲气流TG-CVI法,对初始密度为0.14 g·cm-3的普通碳毡进行致密化处理.研究在不同试验条件下C/C复合材料的致密化过程和密度分布,借助偏光显微镜观察其微观组织,扫描电子显微镜观察其断口形貌,采用三点弯曲法测定C/C复合材料的抗弯强度.结果表明:在热端温度为1080℃、脉冲压力为-3~0 kPa的条件下,经70 h致密化,C/C复合材料的表观密度可达1.836 g·cm-3,且密度分布均匀;组织为粗糙层(RL)和光滑层(SL)的混合型组织;试样断口形貌呈渐变的锯齿状分布,纤维以拔出为主,表现为假塑性断裂特征,抗弯强度为83.91 MPa.
Taking the liquefied gas as carbon source precursor and the nitrogen as dilution gas,the general carbon felt with initial density of 0.14 g·cm-3 was densified by means of directional pulse airflow TG-CVI method.The densification process and density distribution of the C/C composites were studied under different experimental conditions.The microstructure,fracture morphology and flexural strength of the C/C composites were investigated by using polarized light microscopy,scanning electron microscopy and three-point bending method.The result showed that under condition of hot side temperature of 1080℃and pulse pressure of-3~0 kPa,the appearance density of the C/C composites after densified for 70 h would be 1.836 g·cm-3 with uniform density distribution.The microstructure would be a mixed structure of rough laminae(RL)with smooth laminae(SL).The fracture morphology of the samples would exhibit a progressive serrated distribution and the fibers would mainly be of pullout,showing a pseudoplastic fracture feature.In addition,the flexural strength would be 83.91 MPa.
作者
季根顺
赵浩
贾建刚
张胜
李周
郝相忠
JI Gen-shun;ZHAO Hao;JIA Jian-gang;ZHANG Sheng;LI Zhou;HAO Xiang-zhong(State Key Laboratory of Advanced processing and Recycling of Nonferrous Metal,Lanzhou Univ.of Tech.,Lanzhou 730050,China;Technology Center,Gansu Haoshi Carbon Fiber Co.Ltd,Lanzhou 730010,China)
出处
《兰州理工大学学报》
CAS
北大核心
2020年第1期20-23,共4页
Journal of Lanzhou University of Technology
基金
甘肃省科技重大专项(1602GKDD012)
