摘要
利用多尺度模拟的方法建立了针对疲劳损伤累积过程中微裂纹成核与扩展阶段的疲劳损伤多尺度模型,对模型的有效性进行了实验验证,并将其应用于变幅疲劳载荷下某装甲车传动轴的疲劳寿命评估中.研究结果表明,所提模型能同时预测宏观尺度疲劳损伤与细观尺度微裂纹的成核与扩展率,利用该模型所预测的宏观疲劳损伤值与实验所测值相符.该模型既能合理地描述宏观尺度下不同应力水平的疲劳损伤演化过程,又能综合反映细观尺度下微裂纹的成核与扩展行为.利用这种多尺度疲劳损伤模型可以预测结构在疲劳微裂纹成核与扩展阶段所消耗的疲劳寿命,为各类结构疲劳损伤累积过程评估和准确进行寿命预测提供了一种新途径.
A multi-scale fatigue damage model is developed for describing fatigue accumulation dur-ing nucleation and micro-cracks growth by using the multi-scale method and its effectivity is verified by experiments.The multi-scale fatigue damage model is applied to predict the fatigue life of an ar-mored vehicle transmission shaft under variable-amplitude fatigue loading.The results show that the model can predict the fatigue damage and the rate of the nucleation and growth of micro-cracks.The fatigue damage values calculated by using the model are consistent with those measured by experi-ments.The multi-scale fatigue damage model can describe not only fatigue damage evolution under different levels of fatigue stress at the macro-scale,but also the behavior of the nucleation and growth of micro-cracks at the micro-scale.Therefore,the proposed model can predict the fatigue life of engineering structures on the process of accumulated fatigue due to the nucleation and growth of micro-cracks,and it provides a new method for the prediction of fatigue life.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2014年第2期333-338,共6页
Journal of Southeast University：Natural Science Edition
基金
国家自然科学基金资助项目(11072060
51008144)
关键词
疲劳寿命
微裂纹
损伤变量
多尺度损伤模型
寿命预测
fatigue life
micro-crack
damage variable
multi-scale damage model
life prediction
