多轴非比例加载下考虑附加损伤的疲劳寿命预测  

Fatigue life prediction considering the additional damage under multiaxial non-proportional loading

作　　者：朱鹏年 高建雄 袁逸萍[1] 徐蓉霞 吴志峯 ZHU Peng-nian;GAO Jian-xiong;YUAN Yi-ping;XU Rong-xia;WU Zhi-feng(School of Mechanical Engineering,Xinjiang University,Urumqi 830046,China)

机构地区：[1]新疆大学机械工程学院,乌鲁木齐830046

出　　处：《船舶力学》2024年第6期917-924,共8页Journal of Ship Mechanics

基　　金：国家自然科学基金资助项目(52065062);新疆维吾尔自治区自然科学基金资助项目(2020D01C056);新疆大学博士科研启动项目(2020bs12);新疆维吾尔自治区重点研发项目(2021B01003)。

摘　　要：与比例载荷加载相比,在非比例载荷加载时由于附加损伤的产生,机械构件会出现明显的寿命缩短。本文通过分析非比例载荷作用下影响疲劳寿命的因素,提出一个新的非比例损伤因子,以最大剪切面为临界面,建立新的基于等效应变的疲劳寿命预测模型。新的多轴疲劳寿命预测模型不仅考虑法向应力对材料裂纹萌生与裂纹扩展的影响,而且通过引入材料附加强化系数与载荷路径的非比例度反映非比例载荷加载对多轴疲劳寿命的影响。采用5种材料在多轴载荷下的实验数据来验证本文模型的准确性,同时与两种经典模型进行对比,验证与对比分析说明,本文所提模型预测精度较好。The significant life reduction of mechanical components during non-proportional loading com-pared to proportional loading results from the additional damage.In this study,the factors affecting the fa-tigue life under non-proportional loading were analyzed,and a new non-proportional damage factor was pro-posed.A novel fatigue life prediction model based on equivalent strain was established with the maximum shear plane as the critical plane.The new multiaxial fatigue life prediction model not only considers the ef-fect of normal stress on the critical plane on the material crack initiation and crack propagation,but also re-flects the non-proportional loading on the multiaxial fatigue life by introducing the non-proportional harden-ing coefficient of the materials and non-proportionality of the load paths.Experimental data under multiaxial loading of five materials were used to verify the accuracy of the novel model,and were also compared with two classical models.The results show that the prediction accuracy of the proposed model is higher.

关 键 词：多轴疲劳 非比例度 临界面法 等效应变 附加损伤 

分 类 号：TH114[机械工程—机械设计及理论]