全滑动状态下轮轨接触热弹性应力.pdfVIP

第43卷 第1期 西 南 交 通 大 学 学 报 Vo1．43 No．1 2008年2月 JOURNAL OF SOUTHWEST JIAOTONG UNIVERSITY Feb．2008 文章编号：0258-2724(2008)01-0051-06 全滑动状态下轮轨接触热弹性应力 赵 鑫， 金学松， 温泽峰， 吴 磊 (西南交通大学牵引动力国家重点实验室，四川成都610031) 摘 要：用有限元法建立了轮轨接触热一机械载荷耦合计算模型．在传热模型中考虑了轮轨间非稳态热传导以及 轮轨与环境的热对流和热辐射．着重分析因全滑动磨损轮轨接触斑扩大过程中的温度场和应力场，磨损速度对 热弹性应力场的影响，以及轮轨在热一机械载荷共同作用下材料最易发生破坏的位置．计算结果表明，磨损速度 对磨损过程中温度场和应力场的影响很大，轮轨接触表面附近的最大剪应力和剪应变平面与滑动方向所成夹角 约为50。和140。． 关键词：轮轨摩擦；热应力；温度；热传导；有限元法；全滑动 中图分类号：U211．5 文献标识码：A Thermoelastic Stresses Due to eel—Rail Contact in Pure Sliding State ZHAO Xin，JIN Xuesong， WEN Zefeng， WU Lei (Traction Power State Key Lab．，Southwest Jiaotong University，Chengdu 610031，China) Abstract：A finite element method was applied to establish a thermal—mechanical coupling model for wheel—rail contact in pure sliding state．The non—steady heat conduction between the contacting surfaces of wheel—rail，heat—convection and radiation between the wheel—rail and the ambient were considered．Analysis emphases were put on thermal and s~ess fields in the expansion process of contact patch due to wear of pure sliding，the effect of expansion rate of contact patch on thermoelastic stresses，and on failure locations of wheel—rail under the thermal—mechanical loads．Calculation results show the expansion of the contact patch significantly affects temperature and stress distributions，and the planes of maximum shear stress and shear strain are at angles about 50。and 140~with respect to the sliding direction． Key words：wheel—rail friction；thermal stress；temperature；heat transfer；finite element method； pure sliding 轮轨间狭小接触区内的高接触应力和高相对运动速度，使轮轨接触面表层材料产生较高的温升，一旦 接触结束其温度又会迅速下降．因此，轮轨接触区范围内的表层材料承受