C/SiC复合材料紧固件拉-拉疲劳行为研究  

Tension-tension Fatigue Behavior of C/SiC Composite Fasteners

作　　者：袁建宇[1] 逄锦程[1] 王影[1] 谢国君[1] 韩露[1] YUAN Jianyu;PANG Jincheng;WANG Ying;XIE Guojun;HAN Lu(Aerospace Research Institute of Materials&Processing Technology,Beijing 100076)

机构地区：[1]航天材料及工艺研究所,北京100076

出　　处：《宇航材料工艺》2020年第3期81-86,共6页Aerospace Materials & Technology

摘　　要：为了研究C/SiC复合材料紧固件的拉-拉疲劳行为,在疲劳应力比为0.1、加载频率为10 Hz的条件下对不同应力水平的疲劳寿命进行统计。采用断口分析和金相分析方法对C/SiC复合材料螺钉疲劳破坏的细观机制进行了研究。结果表明:C/SiC复合材料螺钉拉-拉疲劳包含拉断疲劳及拉脱疲劳两种失效形式;基于双参数幂指数形式的寿命模型,两种失效形式的疲劳寿命经验公式相似;C/SiC复合材料螺钉的疲劳极限约为拉伸强度的65%~70%,若最大疲劳应力大于0.7σmax,其材料损伤随循环次数增多而明显增大。In order to investigate the tension-tension fatigue behavior of C/SiC composite fasteners,the fatigue life under different stress levels was obtained when the stress ratio was 0.1 and the loading frequency was 10 Hz.Using the fracture analysis and microstructure observation method,the meso-mechanism of fatigue failure of C/SiC composite fasteners was also analyzed.The results indicate that there are two types of failure modes for the tensiontension fatigue behavior including thread breaking and thread pulling off.An empirical two-parameter power exponent form of formula characterizing the fatigue life is proposed,and fatigue life for the two failure modes are similar.The fatigue limit for C/SiC composite fasteners is 65% to 70% of tensile strength,which means that if the maximum fatigue stress is more than 70%σmax,the damage of C/SiC composite significantly increases with cyclic number.

关 键 词：C/SIC复合材料 紧固件 疲劳行为 拉断 拉脱 

分 类 号：TB33[一般工业技术—材料科学与工程]