钢丝绳开裂原因分析

Failure Analysis of Steel Cables

飞机座舱钢丝绳在外场使用过程中发生断裂。该钢丝绳在飞机舱盖开启和关闭时起辅助拉舱盖作用,正常情况下钢丝绳承受拉应力,在飞行过程中会受到振动载荷作用。对钢丝绳外观进行观察;对钢丝绳断口进行宏微观观察、能谱分析;对钢丝绳进行金相组织检查、硬度检测,结果表明:钢丝绳的失效性质为疲劳断裂与过载断裂;钢丝绳的失效原因主要为受载相对较大;钢丝绳表面润滑不足及磨损会对疲劳裂纹的萌生产生促进作用。

The steel cables used in an aircraft cockpit fractured during service.The steel cables were used to pull the canopy when it was opened or closed.The steel cables usually suffered from tensile force,however,it also suffered from vibration load during flight.Based on macro and micro appearance observation,EDS analysis,metallurgical structure inspection and hardness testing,the failure mode and cause of the cables were studied.The results show that the fracture of the steel cables is fatigue fracture and overload fracture.The fracture of the steel cables was caused by the relatively larger load.Besides,poor lubrication and wear promoted the fracture of the steel cables.