滑差对重载列车轮轨黏着特性与表层损伤的影响

在自行研制的小型轮轨滚动磨损实验机上,以CL60车轮钢和U71Mn钢轨钢配副为研究对象,通过控制轮轨的转速,研究滑差对重载列车轮轨黏着特性与表层损伤的影响。结果表明:滑差对轮轨黏着特性存在显著影响,在所测试的若干工况下,随滑差增大,轮轨黏着系数增大;滑差影响轮轨的磨损量,随滑差增大,轮轨磨损量增加;轮轨表面硬度随滑差增大提高;不同滑差下轮轨表面磨损机制不同,纯滚动摩擦时轮轨以疲劳损伤为主;随滑差的增加,轮轨表面磨损机制由轻微的疲劳磨损转变为黏着磨损。此外,在相同滑差下,车轮表面损伤程度较钢轨严重。

Study on the Effect of Slip Rate on the Adhesion Characteristics and Surface Damage of Heavy Haul Train Wheel/Rail Materials

CL60 wheel steel against U71Mn rail steel was chosen as friction pair. The effect of slip rate on adhesion characteristics and surface damage of heavy haul train wheel and rail was studied by using a self-designed wheel-rail rolling contact wear testing machine. The results indicate that the slip rate has a significant influence on the adhesion characteristics of wheel-rail. With the increase of slip rate, the adhesion coefficient of wheelrail increases; slip rate affects the volume of wheel-rail which increases with the increase of slip; the value of wheel -rail surface hardness will be larger than before when the slip rate increases; the wear mechanisms of wheel-rail gradually changes under the different slip rate. During the rolling friction, the surface wear mechanisms is mainly abrasive wear. The wear mechanisms is changed from slightly abrasive to adhesion wear with the increase of slip rate, and the degree of the wheel sample surface damage is larger than that of the rail sample under the same slip rate.