考虑非比例附加损伤的多轴低周疲劳寿命模型  

A NEW MULTIAXIAL FATIGUE LIFE PREDICTION MODEL BASED ON THE NONPROPORTIONAL ADDITIONAL DAMAGE

作　　者：姜潮[1] 邓群[1] 李博川[1] 

机构地区：[1]湖南大学机械与运载工程学院汽车车身先进设计制造国家重点实验室,长沙410082

出　　处：《力学学报》2015年第4期634-641,共8页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家自然科学基金(11172096);国家优秀青年基金(51222502);湖南省杰出青年基金(14JJ1016)资助项目~~

摘　　要：基于临界面法,提出了一种能够反映非比例疲劳寿命锐减现象的多轴低周疲劳寿命模型.与传统临界面模型只考虑附加强化效果不同,新的模型在疲劳损伤参量中引入新定义的非比例附加损伤系数,能综合考虑非比例加载条件下附加强化和载荷路径两种因素对疲劳寿命减少的影响,并且分别以最大切应变和最大损伤平面作为临界面来构建疲劳损伤参量,反映了临界面的选取对模型预测结果的重要影响.从已发表文献中选用8种材料的多轴疲劳试验结果进行验证,新模型能同时适用于比例和非比例加载,并且具有很好的寿命预测精度和材料适用性.Based on the critical plane approach, this paper proposed a multiaxial low cycle fatigue life prediction model to correctly account for the non-proportional fatigue life reduction. Different from traditional critical plane models, in which only consider the effect of non-proportional additional cyclic hardening, the new model takes into account the influence of loading paths on fatigue life by introducing a non-proportional additional damage coefficient into the fatigue damage parameter. By taking the maximum shear strain plane and the maximum damage plane as the critical plane respectively,this model can also reflect the importance of the selected critical plane on the predicted life. Demonstrated by using the experiment data of eight kinds of materials from different published references, this new model is capable for application under both proportional and non-proportional loading conditions, which is very convenient for engineering application.

关 键 词：多轴低周疲劳 寿命预测模型 临界平面法 非比例加载 附加损伤 

分 类 号：TG111.8[金属学及工艺—物理冶金]