U71 Mn钢轨低温性能试验研究

Study on Properties of Rail U71Mn at Low Temperatures

对包钢产U71Mn成分钢种进行了低温系列冲击试验、低温拉伸试验、低温断裂韧度试验,分析讨论了冲击值与低温韧脆转变温度的关系和化学成分、试验温度对强度、塑性以及断裂韧性的影响。试验结果表明,青藏铁路使用中下限成分的U71Mn钢轨,可提高钢轨安全使用性能,满足青藏铁路格拉段低温环境的需要。

Some kinds of mechanical properties of Rail U71Mn, produced by the Baotou Iron ＆ Steel Group, were tested at different low temperature, such as the Charpy U Notch impact, ultimate tensile strength and fracture toughness （K1c）. The relationships between the Charpy impact and Fracture Appearance Transition Temperature were discussed, and the effects of the chemical component and temperature on the strength, plasticity and fracture toughness of rails were analyzed. The results show that it can improve safety of applied Rail U71Mn in the Qinghai-Tibet Railway Line with medium or low limits of chemical components, and such Rail U71Mn can meet the requirements of the low temperature environment along the Geermu-Lhasa Line.