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利用有限元分析软件ABAQUS建立轮轨接触热弹塑性平面应变热机耦合有限元模型。模型中,材料本构采用的是双线性塑性模型,考虑轮轨自由表面与环境的热对流的影响和温度对材料参数的影响,通过移动边界条件模拟轮轨接触区的移动。分析车轮滑动时不同摩擦因数和轴重对钢轨温度场和残余应力分布的影响。计算结果表明,钢轨表面最高接触温升发生在接触斑中心后半轴靠近边缘处,温升主要分布在接触表面大约1.6mm的深度范围,钢轨表层最大VonMises等效应力发生在离钢轨表面大约0.2mm的次表面;残余应力应变的影响主要在钢轨表面大约10mm范围内,在钢轨表面考虑热影响时残余应力比不考虑热影响的大;考虑热影响时钢轨表层的温度随摩擦因数和轴重的增大而增大,钢轨表层残余应力也随着摩擦因数的增大而增大,而轴重对钢轨表面残余应力影响不明显,而在次表层影响很大。
The Finite Element Model of the Coupled Thermo - mechanical Plane - strain Thermo - mechanical Coupling for Wheel - rail Contact Placement Using FEA Software ABAQUS. In the model, the bilinear plasticity model is adopted for the material constitutive model. The influences of the thermal convection on the free surface of the wheel and rail and the environment and the influence of temperature on the material parameters are considered. The moving boundary conditions are used to simulate the movement of the wheel-rail contact zone. The influence of different friction coefficient and axle load on the temperature distribution and residual stress distribution of the rail is analyzed when the wheel slides. The results show that the maximum contact temperature rise of rail surface occurs near the edge of the semi-axis of the contact spot, and the temperature rise is mainly distributed in the depth of about 1.6mm on the contact surface. The maximum Von Mises equivalent stress of the rail surface occurs about 0.2 mm; the influence of residual stress and strain is mainly in the range of about 10mm on the rail surface, and the residual stress on the rail surface is less than the thermal effect without considering the heat effect; Considering the influence of heat on the surface temperature of the rail with the friction factor and axle load The residual stress of the rail surface also increases with the increase of the friction coefficient, while the axial load has no obvious effect on the residual stress of the rail surface, but has a great influence on the subsurface.