通过断口分析、金相检验和硬度测试查明了连接螺柱断裂失效的机理和过程, 并结合有限元分析得出连接螺柱在疲劳载荷下的动响应, 对失效的原因做出判断。结果发现: 连接螺柱疲劳抗力不足以及飞控部件承力构件布局不合理是造成连接螺柱断裂的主要原因。最后, 从工艺和结构方面有针对性地采取了改进和预防措施, 避免同类失效的再次发生, 达到改进产品质量、延长使用寿命、提高服役安全性和可靠性的目的。

The fracture mechanism and process of joint stud were analyzed by means of fracture analysis, metallographic examination and hardness testing. The dynamic responses of connections of stud under fatigue loading were obtained by combining finite element analysis. The results showed that the fracture reason of joint stud was meanly due to the lack of fatigue resistance of joint stud and the unreasonably arranged distribution of flight control component. Finally, the improvement and preventive measures in techniques and structures were made, which kept the failure from happen. The resulted products were then better in quality, prolonged in life cycle, safer and more reliable.