基于连续介质损伤力学理论并结合修正循环强度系数法,研究非比例加载对材料高周疲劳寿命的影响,建立一种多轴应力当量折算高周疲劳损伤强化模型。同时根据常规微塑性应变高周疲劳损伤演化模型给出的S-N曲线方程以及修正循环强度系数法...基于连续介质损伤力学理论并结合修正循环强度系数法,研究非比例加载对材料高周疲劳寿命的影响,建立一种多轴应力当量折算高周疲劳损伤强化模型。同时根据常规微塑性应变高周疲劳损伤演化模型给出的S-N曲线方程以及修正循环强度系数法基本原理对所建模型的材质参数识别方法进行阐述。以航空工业常用的金属材料铝合金LY12CZ和30Cr Mn Si A钢为计算实例,得到两种材料的模型参数。将已建的损伤演化模型嵌入到ABAQUS的UMAT子程序中,实现了对受损试件的损伤追踪以及寿命预测。两种材料计算结果表明,新建模型的预测效果均在3倍误差以内,与试验吻合较好。此外,还对比分析现有的其他多轴寿命预测模型的预测效果,结果表明,新建模型更适合于多轴高周疲劳寿命预测。展开更多
Corrected stress field intensity obtained by averaging the superior limit of intrinsic damage dissipation work in critical domain, which considers thoroughly thermodynamic consistency within irreversible thermodynamic...Corrected stress field intensity obtained by averaging the superior limit of intrinsic damage dissipation work in critical domain, which considers thoroughly thermodynamic consistency within irreversible thermodynamic framework, was proposed for predictions of high-cycle fatigue endurance limits. Simultaneously, the effects of mean stress, additional hardening behavior related to non-proportional loading paths and stress gradients on multiaxial high-cycle fatigue are taken into account in the proposed approach. The approach is an extension of the general stress field intensity. For a better comparison, existing multiaxial high-cycle fatigue criteria were employed to predict the endurance limits of different metallic materials subjected to different multiaxial loading paths, and it is shown that present proposal performs better from statistical value of error indexes, which make the proposed approach of corrected stress field intensity and its associated concepts provide a new conception to predict endurance limits of multiaxial high-cycle fatigue with high accuracy.展开更多
文摘基于连续介质损伤力学理论并结合修正循环强度系数法,研究非比例加载对材料高周疲劳寿命的影响,建立一种多轴应力当量折算高周疲劳损伤强化模型。同时根据常规微塑性应变高周疲劳损伤演化模型给出的S-N曲线方程以及修正循环强度系数法基本原理对所建模型的材质参数识别方法进行阐述。以航空工业常用的金属材料铝合金LY12CZ和30Cr Mn Si A钢为计算实例,得到两种材料的模型参数。将已建的损伤演化模型嵌入到ABAQUS的UMAT子程序中,实现了对受损试件的损伤追踪以及寿命预测。两种材料计算结果表明,新建模型的预测效果均在3倍误差以内,与试验吻合较好。此外,还对比分析现有的其他多轴寿命预测模型的预测效果,结果表明,新建模型更适合于多轴高周疲劳寿命预测。
基金The authors gratefully acknowledge the support provided by Key Natural Science Foundation of Hebei Province of China （E2017203161）.
文摘Corrected stress field intensity obtained by averaging the superior limit of intrinsic damage dissipation work in critical domain, which considers thoroughly thermodynamic consistency within irreversible thermodynamic framework, was proposed for predictions of high-cycle fatigue endurance limits. Simultaneously, the effects of mean stress, additional hardening behavior related to non-proportional loading paths and stress gradients on multiaxial high-cycle fatigue are taken into account in the proposed approach. The approach is an extension of the general stress field intensity. For a better comparison, existing multiaxial high-cycle fatigue criteria were employed to predict the endurance limits of different metallic materials subjected to different multiaxial loading paths, and it is shown that present proposal performs better from statistical value of error indexes, which make the proposed approach of corrected stress field intensity and its associated concepts provide a new conception to predict endurance limits of multiaxial high-cycle fatigue with high accuracy.
