CL65车轮钢滚动疲劳磨损研究

Research on Rolling Fatigue Wear of CL65 Wheel Steel

利用双盘滚动磨损实验机对CL65车轮钢与U75V钢轨钢进行滚动磨损实验,研究CL65车轮钢表面出现的疲劳磨损现象。实验表明:CL65车轮钢的磨损情况由黏着磨损不断向疲劳磨损过渡。机加工表面细晶层主要出现在磨损的初始阶段,疲劳磨损裂纹的形成和扩展出现在细晶层内或细晶层与基体的界面,导致了细晶层的早期疲劳剥离。随着磨损周次的不断增加,原始片状珠光体和先共析铁素体,基体区域表层的塑性变形不断加剧,当塑性应变过大时,疲劳裂纹开始萌生,并逐渐开始向先共析铁素体区域、渗碳体与共析铁素体界面扩展。

The rolling wear experiments of CL65 wheel steel and U75V rail steel were carried out on a double-disk rolling wear tester to study the fatigue wear phenomenon on the surface of CL65 wheel steel.During the experiment,it is found that the wear condition of CL65 wheel steel is changed from adhesive wear to fatigue wear.The fine grain layer on the machined surface mainly appears in the initial stage of wear,and the formation and propagation of fatigue wear cracks are easy to appear in the fine grain layer or the interface between the fine grain layer and the matrix,which leads to the early fatigue peeling off of the fine grain layer.With the continuous increase of wear cycles,the plastic deformation of the surface layer of the original flake pearlite plus syntectoid ferrite is increased continuously.When the plastic strain is too large,the fatigue crack begins to germinate and gradually began to expand in the region of proeutectoid ferrite and the interface between cementite and eutectoid ferrite.