考虑焊接残余应力的钢轨铝热焊焊缝滚动接触应力分析  

Analysis of Rolling Contact Stress in RailAluminothermic WeldJoints Considering Weld Residual Stress

作　　者：张玉华 李澳 朱永辉 胡伟平[2] ZHANG Yuhua;LI Ao;ZHU Yonghui;HU Weiping(China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;Beihang University,Beijing 100191,China;China Railway Jinan Bureau Group Co.,Ltd.,Jinan 250001,China)

机构地区：[1]中国铁道科学研究院集团有限公司,北京100081 [2]北京航空航天大学,北京100191 [3]中国铁路济南局集团有限公司,济南250001

出　　处：《高速铁路技术》2024年第5期59-66,共8页High Speed Railway Technology

摘　　要：铝热焊焊缝的滚动接触应力是钢轨滚动接触疲劳问题的关键影响因素。本文开展了静力拉伸试验研究母材与焊缝材料的基本力学性能,采用Chaboche塑性本构方程描述两种材料在塑性阶段的力学响应。利用ABAQUS计算了铝热焊焊接过程的温度场和残余应力场。建立了轮轨滚动接触应力分析的有限元计算模型,并将焊接残余应力分析与焊缝滚动接触应力相结合,提出了考虑焊接残余应力的轮轨滚动接触应力计算方法。最后,分析了焊缝局部应力场的特点。研究结果表明:(1)焊缝边缘处相比中心处承受更大的接触压力,残余应力的存在会增加焊缝的滚动接触应力以及焊缝边缘处的接触压力;(2)随着车轮滚动次数的增加,焊缝的塑性应变会不断累积,进而影响钢轨疲劳伤损的演化。Rolling contact stress in aluminothermic weld joints plays a crucial role in rail rolling contact fatigue issues.In this study,static tensile tests were conducted to investigate the fundamental mechanical properties of parent rail material and weld metal.The Chaboche plastic constitutive equation was adopted to describe the mechanical response of both materials in the plastic regime.Utilizing ABAQUS software,the temperature field and residual stress field during the aluminothermic welding process were calculated.A finite element computational model was established to analyze rolling contact stress between wheel and rail,integrate the assessment of weld residual stress with the calculation of rolling contact stress in the weld zone.This led to the proposal of a method for calculating rail-wheel rolling contact stress that accounts for the presence of welding residual stress.Lastly,the characteristics of the local stress field within the weld were analyzed.The results show that:(1)The edges of the weld bear higher contact pressures compared to the center,and the presence of residual stress exacerbates rolling contact stress and contact pressure at the weld edges.(2)As the number of wheel revolutions increases,plastic strain accumulates in the weld,consequently influencing the evolution of rail fatigue damage.

关 键 词：铝热焊 焊接热过程 焊接残余应力 滚动接触应力 有限元 

分 类 号：U2139.2[交通运输工程—道路与铁道工程] TG[金属学及工艺]