三角支架断裂的失效分析

Failure Analysis of Fracture with Triangle Bracket

利用各种检测设备对断裂的三角支架进行研究。结果表明:三角支架的组织、成分、硬度合格。裂纹源位于断口表面位置,此处化学成分无异常,没有其它夹杂物。支架台架试验中用的夹具内侧有严重的磨损,表面上凸凹不平,在反复交变应力下对支架断口的位置造成了损伤,产生了裂纹源,最终导致了早期断裂,这是断裂的根本原因。更换工装夹具后重新进行试验,疲劳寿命25.6万次,达到了技术要求。

A variety of testing equipment were used to study the broken triangular bracket. The results show that the structure, composition and hardness of triangular scaffold are qualified. The crack source is located on the fracture surface,where the chemical composition is normal and there are no other inclusions. The inside of the fixture used in the bench test has serious wear and tear, and the surface is uneven. Under the repeated alternating stress, the fracture location of the triangular bracket is damaged and the crack source is produced, which eventually leads to the early fracture, which is the fundamental reason for the fracture. The fatigue life is 256000 times, which can meet the technical requirements.