BNbRE与U75V钢轨的疲劳寿命及断口分析

Fatigue Life and Fracture Analysis of BNbRE and U75V Rail

对稀土和U75V重轨钢进行成分检验及室温拉伸实验。在保证实验材料冶炼质量和力学性能符合标准要求的基础上,对两种钢轨进行疲劳实验和断口观察,并对其疲劳性能进行分析。结果表明:两种材料的疲劳寿命曲线(SN曲线)在较大作用力下寿命较快下降;随着施加外力的降低,曲线斜率变小,寿命延长。整体而言,在同一施加力下稀土钢要比U75V重轨钢的寿命长。

The components test and room temperature tensile experiments of the rare earth steel and U75V heavy rail steel were carried out. On the basis of ensuring the quality and mechanical properties of the test materials which meet the standard requirements, the fatigue test and fracture observation of the above steels were carried out, then the fatigue properties were carried out. The results indicate that the fatigue life curve(S-N curve) of the two materials decrease rapidly under the large force. The slope of curve is smaller and the life is longer with the reduction of external forces. Overall, the rare earth steel has a longer life than that of U75V heavy rail steel under the same force.