SiC/SiC复合编织管的抗热冲击性能与失效机理研究  

Thermal shock resistance and failure mechanism of SiC/SiC composite braided tubes

作　　者：胡庆宽 许琦鹏 万志慧 杨保建 周为 晋小超 HU Qingkuan;XU Qipeng;WAN Zhihui;YANG Baojian;ZHOU Wei;JIN Xiaochao(Henan Key Laboratory of Fastening and Connection Technology,Henan Aerospace Precision Manufacturing Co.,Ltd.,464000 Xinyang,China;Joint Research Center for Extreme Environment and Protection Technology,School of Aerospace Engineering,Xi'an Jiaotong University,710049 Xi'an,China)

机构地区：[1]河南航天精工制造有限公司河南省紧固连接技术重点实验室,信阳464000 [2]西安交通大学航天航空学院极端环境与防护技术联合研究中心,西安710049

出　　处：《应用力学学报》2024年第2期288-296,共9页Chinese Journal of Applied Mechanics

基　　金：国家重大科技专项资助项目(No.J2019-IV-0003-0070);国家自然科学基金资助项目(No.12102320);中国博士后科学基金资助项目(No.2021M692571)。

摘　　要：以二维二轴编织的SiC/SiC复合编织管为研究对象,研究其抗热冲击性能及失效机理。自主搭建了基于石英灯辐照加热的循环热冲击试验平台,基于该平台开展了SiC/SiC复合编织管的循环热冲击试验考核,并对循环热冲击后的复合编织管进行了径向压缩测试,探究了复合编织管力学性能与破坏机理,拟合得到了热冲击强度退化经验公式。研究结果表明,搭建的循环热冲击试验平台能够模拟快速升降温的实际服役环境,最高升温、降温速率在试验过程中分别可达约40、60℃/s。随着热冲击循环次数的增加,SiC/SiC复合编织管环向拉伸强度下降,且降幅随之增大。热冲击产生的热应力导致纤维周围的基体产生微裂纹,弱化了纤维束与基体之间的连接,这是复合编织管强度降低的原因之一。拟合的强度退化经验公式能够准确描述强度退化规律,可以满足工程应用需求。The two-dimensional two-axis braided SiC/SiC composite braided tubes are taken as the research object,and their thermal shock resistance and failure mechanism are studied.A thermal shock test platform based on quartz lamp irradiation heating was built,on which the thermal shock test of SiC/SiC composite braided tubes was carried out,and then the diametral compression test of the braided tubes after thermal shock was also performed.The mechanical properties and failure mechanism of the braided tube were investigated,and the empirical formula of thermal shock strength degradation was obtained by fitting.The results showed that the thermal shock test platform can simulate the service environment with rapid temperature rise and drop,and the maximum heating and cooling rates can reach about 40 and 60℃/s,respectively,during the thermal shock test.With the increase of thermal shock cycle number,the circumferential tensile strength of SiC/SiC composite braided tubes decreases quickly at an increasing rate.The thermal stress caused by thermal shock leads to the appearance of microcracks in the matrix around the fiber and weakens the adhesion between the fiber bundle and matrix,which is one of the main causes of the strength degradation of braided tube.The fitting algorithm can well describe the strength degradation caused by cyclic thermal shock and has the value of engineering applications.

关 键 词：陶瓷基复合材料 SiC/SiC复合编织管 石英灯辐照加热 热冲击 失效机理 

分 类 号：O348.5[理学—固体力学]