裂扩门槛值试验数据与钢轨性能关系的探讨

Discussions on Relation between Test Data of Threshold Values of Crack Expansion and Performances of Rails

文章在U71Mn、U75V和U20Mn淬火轨、以及加稀土镧和铈的U75V试验钢裂扩门槛值ΔK_(th)试验的基础上,通过试验获取的数据和图表,分析了钢轨组织、夹杂物、氢超标和残余应力等因素与Crack Length-Cycle曲线的关系,以及钢轨加入稀土镧合金、铈合金之后对钢轨裂纹扩展的影响,为分析钢轨性能、延长钢轨寿命提供新的手段。

In the paper,the relations between such factors as the microstructure of rails,inclusions,excessive hydrogen and residual stress and Crack Length-Cycle curve are analyzed through the data and diagrams obtained by the tests based on the test of threshold value of crack expansionΔK th for U71Mn,U75V and U20Mn quenched rails as well as U75V test steel with the rare earth,lanthanum and cerium.Moreover,the effects of adding the rare earth,lanthanum alloy and cerium alloy into rails on crack growth of rails are analyzed,which could provide new means for analyzing the performances of rails and prolonging service life of rails.