Effect of triaxial stress constraint on ratcheting behavior and low cycle fatigue life of polypropylene
To develop low cycle fatigue damage models describing the effect of stress triaxiality, a series of low cycle fatigue tests of polypropylene are carried out under stress-controlled mode on circumferentially notched bars with different notch radii to generate different triaxial stress fields. The effect of stress triaxiality and stress level on ratcheting strain and fatigue life has been studied. It is found mat ratcheting strain increased and fatigue life decrease with the increase of stress triaxiality at the same stress level. Ratcheting strain has detrimental effect on the fatigue life. Ratcheting strain should be introduced into damage models. Ratcheting strain increase and fatigue life decrease with the increase of stress level at low stress triaxiality. At the high stress triaxiality with low stress level, ratcheting strain and fatigue life are dependent on material defects rather than stress level. The phenomenon was explained by Rice-Tracey void growth model.
Yan-xia Wu Wei-yi Chen
Department of Engineering Mechanics, Tai Yuan University of Technology, Taiyuan 030024, China
国际会议
The 5th International Conference on Nonlinear Mechanics(第五届国际非线性力学会议)
上海
英文
873-876
2007-06-11（万方平台首次上网日期，不代表论文的发表时间）