幂硬化对准静载弹塑性弯曲裂纹J积分的影响  

IMPACT OF HARDENING ON J INTEGRAL AT THE SLIGHTLY CURVED ELASTICITY-PLASTICITY CRACK TIP UNDER QUASI-STATIC LOADS

作　　者：杨大鹏[1,2] 王均杰[1] 赵耀[2] 李天匀[2] YANG DaPeng WANG JunJie ZHAO Yao LI TianYun(Department of Mechanical Engineering, Zhengzhou Technical College, Zhengzhou 450121, China School of Naval Architecture ＆ Ocean Engineering, Huazhong University of Science and Technology, Wuhan 430074, China)

机构地区：[1]郑州职业技术学院机械工程系,郑州450121 [2]华中科技大学船舶与海洋工程学院,武汉430074

出　　处：《机械强度》2016年第5期1099-1102,共4页Journal of Mechanical Strength

基　　金：河南省基础与前沿技术研究计划项目(152300410003);国家自然科学基金重大研究计划项目(91016026)资助~~

摘　　要：主要研究准静载荷作用下的硬化材料弹塑性弯曲裂纹尖端的J积分问题。综合考虑了准静作用应力,塑性区域边界上正应力与剪应力,利用二阶摄动方法与卡氏定理计算了硬化材料弹塑性弯曲裂纹尖端的J积分。作图分析了弹塑性弯曲裂纹尖端J积分大小与材料硬化指数之间的变化关系。在幂硬化材料中,弹塑性弯曲裂纹尖端J积分随着材料硬化指数n的增大而减少,当n等速均匀增加时,弹塑性弯曲裂纹尖端J积分加速减少,减少的幅度越来越大。当材料的硬化指数相同时,弯曲裂纹尖端J积分随外载荷的不断减小而逐渐减小。建立了一个计算硬化材料弹塑性弯曲裂纹J积分的理论模型。Jintegral of elastic-plastic curved crack in hardened material under quasi-static loads has been mainly studied, and curved crack tip J integral has been calculated as a practical application of a second order perturbation method and theorem of surname KA, where the effects of quasi-static applied stresses and quasi-static normal and shear stresses on the boundaries of plasticity area are synthetically taken into considerations. Diagrams have been constructed to analyse the transformation relationships between curved crack J integral and hardening exponents. Curved crack J integral will decrease when hardening exponents increase in hardened material. Curved crack J integral decrease extent will be more and more severe when hardening exponents increase evenly. Curved crack J integral will decrease when external loads decrease with the same hardening exponents. A theoretical model where J integral of elastic-plastic curved crack was calculated has been established in hardened material.

关 键 词：准静载荷 硬化材料 弯曲裂纹 二阶摄动方法 J积分 

分 类 号：TB301[一般工业技术—材料科学与工程]