U71Mn钢轨断裂分析

摘要

The causes of unusual fracture of heavy rail in some railway are analysed by means of macroscopical and microscopic analysis methods. The result shows that collision once happened at the edge of rail base, and then results in work-hardening and micro-crack . The crack extends continuously to the whole cross section under the effect of stress and stress concentration,and the heavy rail fractures completely in the end. Measures are also put forward to reduce the rail damages.%通过宏观和微观观察，分析某铁路线重型钢轨发生异常断裂的原因。结果表明，轨底边缘曾受到机械碰撞而产生加工硬化及微裂纹，在应力及应力集中共同作用下，裂纹不断扩展至整个截面而导致重轨断裂失效，提出减少钢轨伤损发生的措施。