疲劳载荷作用下焊接点三维线弹性弯曲裂纹路径预测（英文）  

Three Dimensional Crack Path Prediction of Brittle Fracture in Weldment Under Fatigue Load

作　　者：杨大鹏[1,2] 潘海洋[3] 赵耀[2] 李天匀[2] YANG Da-peng PAN Hai-yang ZHAO Yao LI Tian-yun(Mechanical Engineering Department, Zhengzhou Technical College , Zhengzhou 450121, China School of Naval Architecture ＆ Ocean Engineering, Huazhong University of Science and Technology, Wuhan 430074, China Zheng Zhou Technical College, Urban Rail Transport Department, Zhengzhou 450121, 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 [3]郑州职业技术学院城市轨道交通系,郑州450121

出　　处：《船舶力学》2017年第3期318-328,共11页Journal of Ship Mechanics

基　　金：Supported by Henan Province Basic and Advanced Technology Research Plan Project(No.152300410003);The Training Program of the Major Research Plan of the National Natural Science Foundation of China(No.91016026)

摘　　要：利用二阶摄动方法研究了疲劳载荷作用下结构线弹性裂纹的弯曲扩展问题并求解了三维动态应力强度因子。利用二阶摄动方法研究了疲劳载荷作用下裂纹路径预测时的应力准则与能量准则之间的关系。就均匀物质而言,在二阶摄动分析理论的框架内,两种准则指明了相同的三维疲劳弯曲裂纹扩展路径。但在具有非均匀断裂韧度的物质中,能量准则优越于应力准则。作为二阶摄动方法的实际运用,研究了焊接结构中疲劳线弹性裂纹的形态特征和弯曲扩展路径问题,综合考虑了诸如远场动态作用应力、焊接残余应力、局部物质衰变以及不同尺寸的缺陷的存在等因素,绘制出疲劳载荷作用下退化区域中裂纹弯曲扩展的临界轨迹曲线。Based on a second order perturbation method, three dimensional fatigue stress intensity factors are analyzed for a curved crack. The method is extended to obtain an approximate representation of a three dimensional fatigue stress intensity factors at the tip of a curved crack. A fatigue energy release rate due to three dimensional curved crack growth can be calculated by using Irwin＇s formula. Considerations are made for a three dimensional fatigue curved crack in materials with inhomogeneous fracture toughness. Paths of a brittle three dimensional fatigue curved crack propagating along a welded joint are predicted as a practical application of the present method, where the effects of fatigue applied stresses, residual stresses, and material deterioration due to welding are taken into considerations.

关 键 词：三维疲劳应力强度因子 弯曲裂纹 二阶摄动方法 疲劳能量释放率 

分 类 号：O343[理学—固体力学]