材料科学与工程学报2013，Vol.31Issue(3)：427-431,463,6.
7050-T7451铝合金低周疲劳平均应力松弛规律
Mean Stress Relaxation during Low-cycle Fatigue of Aluminum Alloy 7050-T7451
摘要
Abstract
In order to investigate the effect of the mean strain on low-cycle fatigue behavior of 7050-T7451 aluminum alloy,a series of uniaxial low-cycle fatigue tests with different strain ratios (R=-1,-0.06,0.06 and 0.5) were performed at room temperature in an ambient air.Under symmetric cyclic straining,the alloy exhibits cyclic softening characteristics,as a whole,while under asymmetric cyclic straining,the material presents initial hardening followed by cyclic stabilization.It is shown that the asymmetric cyclic straining causes the relaxation of the mean stress dependent on the applied strain amplitudes,which was further described by using Landgraf model and non-linear Maxwell model.It is pointed out that the relaxation behavior of the mean stress during asymmetric cyclic straining of the alloy can be well described by nonlinear Maxwell model at all strain amplitudes investigated,while it can only be described accurately at relatively lower strain amplitudes by Landgraf model.关键词
低周疲劳/平均应力松弛/7050-T7451铝合金Key words
low-cycle fatigue/ mean stress relaxation/ 7050-T7451 aluminum alloy分类
矿业与冶金引用本文复制引用
陈胤桢,郝红,王利发,刘建中,叶笃毅..7050-T7451铝合金低周疲劳平均应力松弛规律[J].材料科学与工程学报,2013,31(3):427-431,463,6.基金项目
国家高科技研究发展计划资助项目(2009AA044802)与国家自然科学基金资助项目(50975254) （2009AA044802）
