裂纹尖端疲劳塑性区研究  

Research on Cyclic Plastic Zone near Crack Tip

作　　者：滕项铭[1] 冯淼林[1] 

机构地区：[1]上海交通大学船舶海洋与建筑工程学院工程力学系,上海200030

出　　处：《力学季刊》2011年第3期418-426,共9页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金项目(10772115);国家自然科学基金重点项目(10932007)

摘　　要：循环塑性区大小是疲劳断裂研究中非常重要的一个参数。本文运用数值方法,考察了不同塑性本构模型、有限单元尺寸、几何非线性、载荷比等参数对于裂纹尖端疲劳塑性区大小的影响。结果发现除塑性本构模型外其他参数对于裂纹尖端疲劳塑性区大小影响不大。同时对Ⅰ、Ⅱ型混合裂纹在多轴非比例载荷下给出了由Jiang和Kurath定义的疲劳塑性区,由于其定义与应力强度因子无关,可以适用于复杂疲劳载荷下的混合型裂纹。The cyclic plastic zone size is an important parameter in the investigation of fatigue fracture.Using numerical method,the influence factors were studied on the cyclic plastic zone size,which are the plastic constitutive models,the element size near crack tip,non-linear geometry and load ratio.It finds that all the other factors have little influence on the cyclic plastic zone size except the plastic constitutive models.The cyclic plastic zone determination by Jiang and Kurath was conducted for Ⅰ,Ⅱ combined mode crack under multiaxial non-proportional loading.Because the theory is not related to the stress intensity factor,it could be used for the mixed mode crack under complex cyclic loading.

关 键 词：疲劳塑性区尺寸 多轴非比例载荷 应力强度因子 混合裂纹 

分 类 号：O346.12[理学—固体力学]