滑动速度对钢轨表面接触应力的影响

摘要

A elastic plane strain finite element model of wheel-rail system was established using the finite element anal-ysis software ANSYS to simulate the sliding contact behavior of wheel-rail in the working condition.The effect of sliding speed on the contact stress of the rail contact surface in the condition of mechanical loading,and the effect of sliding speed on the frictional temperature rise and contact stress in the condition of thermal-mechanical coupled load were investigated. The contact stress calculated under these two conditions was compared.Results show that the contact stress gets a signifi-cant increase and the distribution is more concentrated on the vicinity of the contact areas in the coupled load conditions compared with the mechanical load conditions,which means the significant friction thermal effect is generated by the rela-tive sliding between wheel-rail.With the increasing of sliding speed,the friction thermal effect is more obvious,and the depth of the heat-affected layers becomes shallower,which means sliding speed has a significant influence on the contact stress,and the impact of sliding speed on the contact stress should be taken into consideration when investigating the con-tact stress of rail.%利用ANSYS有限元软件建立轮轨系统弹性平面应变有限元简化模型，模拟轮轨滑动接触行为。研究机械载荷条件下滑动速度对钢轨接触表面接触应力的影响，以及热-机耦合载荷条件下滑动速度对钢轨表面接触应力、摩擦温升的影响，并对2种条件下的接触应力进行比较分析。结果表明：耦合载荷条件下的接触应力较机械载荷条件下显著增加，分布更集中于接触斑附近，即轮轨相对滑动产生了明显的摩擦热效应；滑动速度增加，摩擦热效应越明显，热影响层越浅，即滑动速度对接触应力有显著影响，钢轨接触应力分析时必须考虑滑动速度的影响。