基于临界面损伤参量的金属材料多轴疲劳寿命预测  

Multiaxial Fatigue Life Prediction of Metallic Materials Based on Critical Plane Damage Parameter

作　　者：赵而年[1] 瞿伟廉[1] 周强[1] 

机构地区：[1]武汉理工大学道路桥梁与结构工程湖北省重点实验室,湖北武汉430070

出　　处：《华南理工大学学报（自然科学版）》2017年第2期130-136,152,共8页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51438002;51378409)~~

摘　　要：对最大剪切应变幅模型、KBM模型、FS模型和MKBM模型4种广泛讨论的临界面模型进行了对比分析,统计了8种金属材料圆管薄壁型试件在173个应变加载工况下的多轴疲劳试验数据,验证了这4种临界面模型对金属材料多轴疲劳寿命的预测能力,讨论了基于临界面损伤参量进行多轴疲劳损伤评估和寿命预测时仍需关注的几个主要问题.研究结果表明:最大剪切应变幅模型和KBM模型能较好地适用于多轴比例加载条件下的疲劳寿命预测,而对多轴非比例疲劳寿命的预测结果一般偏于危险估计;FS模型和MKBM模型在损伤控制参量中引入了一个临界面上的最大法向正应力参数来反映材料的非比例附加强化效应对多轴疲劳损伤的影响,显著提高了对多轴非比例疲劳寿命的预测能力.In order to verify the applicability of four widely-used critical plane models （ including the maximum shear strain amplitude model, the KBM model, the FS model and the MKBM model） to the multiaxial fatigue life prediction of metallic materials, a comparison of these models were performed according to the statistical data of multiaxial fatigue test of the thin-walled tubular specimens with 8 kinds of metallic materials under 173 straining conditions. Additionally, some major problems existing in the fatigue damage evaluation and the fatigue life predic-tion based on critical plane parameters are discussed. The results show that both the maximum shear strain ampli-tude model and the KBM model accurately predict the fatigue life of the specimen under multiaxial proportional loading conditions, while non-conservative fatigue life is obtained when the specimen is under the action of multiax-ial non-proportional load. Moreover, it is found that both the FS model and the MKBM model work well for the mul-tiaxial non-proportional fatigue life prediction due to the introduction of the maximum normal stress acting on the critical plane which can reflect the effect of materiaPs non-proportional additional hardening on the multiaxial fatigue damage.

关 键 词：多轴疲劳 疲劳寿命预测 临界面法 非比例加载 

分 类 号：TG111.8[金属学及工艺—物理冶金] O346.2[金属学及工艺—金属学]