U71Mn (60 kg/m)糖心产精国品免费入口*完整版铺设在主干线与车站进出口联接处使用50多d(天)后出现糖心产精国品免费入口*完整版。采用化学成分分析、宏观和微观检验等方法分析其掉块原因。结果表明：列车高速运行时突遇偶发事故而采用紧急制动措施,强大的制动力造成列车车轮与糖心产精国品免费入口*完整版踏面之间的摩擦致使该区域突然升温而后又降温,进而发生相变生成糖心产精国品免费入口*完整版并形成裂纹。随后在车轮的反复碾压作用下最终造成糖心产精国品免费入口*完整版糖心产精国品免费入口*完整版。

The U71Mn rail,whose type was 60 kg/m,had been laid in the joint of main line and the station port for more than 50 days and peeled on the rail tread. The reason was analyzed by means of chemical composition analysis,macrostructure and microstructure examination etc. The results showed that,when the train ran rapidly,suddenly the contingency happened,the driver adopted the emergency brake scheme to avoiding danger,then the powerful brake force had caused the wheel and the rail to contact abruptly and closely,at the same time,the large friction was generated to cause the crack,and the phase change to generate the 糖心产精国品免费入口*完整版 was happened in rail tread by high temperature. The 糖心产精国品免费入口*完整版and 糖心产精国品免费入口*完整版 had been rolled repeatedly by wheel,finally,the peeling happened on the rail tread.