内燃机车车轴断裂原因分析

Research on Fracture of Internal Combustion Locomotive Axle

某型号机车车轴在使用中发生断裂,通过对失效车轴进行宏观检查、断口分析、金相组织检验、化学成分分析、性能测试和运行状况调查等,对断裂原因进行了分析。结果表明,机车运行中发生过抱轴瓦烧瓦,轴表面产生了热应力微裂纹,部分微裂纹在工作应力的作用下疲劳扩展,最终疲劳断裂。

The axle of a locomotive fractured in service. To find out the reason of the fracture, the macro examination, fracture, microstructure and chemical composition, mechanical property and even mode of operation of the axle were analyzed. The results show that axle suspension hush was overburnt and there were thermal stress microcracks on the surface of the axle. Some microcracks expanded under the action of working stress, and finally fatigue fracture happened to the axle.