装甲车辆被动轴断裂失效分析

Fracture Failure Analysis of the DrivenShaft for Armored Vehicles

被动轴是装甲车辆侧减速器的主要零部件,在行驶过程中起着支撑、动力输出和传递扭矩的重要作用,其材质为38CrSi。某批被动轴在装甲车跑车试验过程中发生断裂。通过对断裂件进行宏观断口、化学成分、金相组织检测,并采用有限元法对被动轴进行应力情况模拟,分析了被动轴的断裂属性及原因。结果表明,被动轴断裂为多源脆性开裂,主要是由于热处理后被动轴内部出现组织偏析、不均匀以及轴径处存在较大的应力集中引起的。

Driven shaft was the key part of decelerator of armored vehicles,it played an important role in supporting,power taking-off and transmitting torque during driving,and it was made of 38CrSi steel.The fracture of armored vehicles driven shaft happed when running.The fracture features and reasons were analyzed by means of macro analysis,chemical composition analysis,microstructure test and using FEM method to numerical simulate stress.The results showed that the fracture feature of driven shaft was multi-source brittle fracture,the fracture was mainly caused by the structure segregation and inhomogeneity after heat treatment and the serious stress concentration on the shaft diameter changing position.