基于晶体塑性有限元模拟的EA4T车轴钢裂纹萌生寿命预测  

Prediction of Crack Initiation Life of EA4T Axle Steel based on Crystal Plastic Finite Element Simulation

作　　者：周素霞 曲直[1,2] 张昭 吴毅 ZHOU Suxia;QU Zhi;ZHANG Zhao;WU Yi(School of Mechanical-Electronic and Vehicle Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044;Beijing Key Laboratory of Service Performance of Vehicles,Beijing University of Civil Engineering and Architecture,Beijing 100044;Metal&Chemistry Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081)

机构地区：[1]北京建筑大学机电与车辆工程学院,北京100044 [2]北京建筑大学城市轨道交通车辆服役性能保障北京市重点实验室,北京100044 [3]中国铁道科学研究院集团有限公司金属及化学研究所,北京100081

出　　处：《机械工程学报》2025年第6期277-284,共8页Journal of Mechanical Engineering

基　　金：北京市自然科学基金资助项目(L211007)。

摘　　要：依据吉布斯自由能变化值作为疲劳裂纹萌生判据,构建缺陷车轴钢疲劳裂纹萌生寿命预测模型。通过疲劳试验探究EA4T车轴钢材料裂纹萌生变形机制,结合晶体塑性理论框架构建外部缺陷车轴有限元晶体模型,并结合疲劳试验与有限元仿真获取该晶体模型下的能效因子f_(。)从微观角度对车轴缺陷附近应力场及结构变形进行分析,探究外部缺陷对车轴裂纹萌生寿命的影响。对环状划痕和菱形这两种缺陷车轴模型进行塑性应变能密度的标定和寿命预测。结果表明:环状划痕缺陷高应力集中范围更广,对材料组织结构产生的破坏范围更大,更容易发生疲劳破坏。环状划痕缺陷的裂纹萌生寿命低于菱形缺陷,缺陷面积大,对裂纹萌生寿命的影响更严峻。According to the change of Gibbs free energy as the fatigue crack initiation criterion,the fatigue crack initiation life prediction model of defective axle steel is established.The deformation mechanism of crack initiation of EA4T axle steel was explored by fatigue test,and the finite element crystal model of external defect axle was constructed based on the theoretical framework of crystal plasticity.The energy efficiency factor f of the crystal model was obtained by fatigue test and finite element simulation.From the microscopic point of view,the stress field and structural deformation near the axle defects are analyzed to explore the influence of external defects on the crack initiation life of the axle.The plastic strain energy density and life prediction of two kinds of defective axle models,ring scratch and diamond,are carried out.The results show that the high stress concentration range of annular scratch defect is wider,the damage range of material structure is larger,and fatigue failureis more likely to occur.The crack initiation life of annular scratch defects is lower than that of diamond defects,and the defect area is larger,which has a more severe effect on the crack initiation life.

关 键 词：晶体塑性 外部缺陷 吉布斯自由能 裂纹萌生寿命 

分 类 号：U270[机械工程—车辆工程]