疲劳荷载作用下的三维弹塑性弯曲裂纹尖端张开位移  

Three dimensional elastic-plastic curved crack tip opening displacement under fatigue load

作　　者：杨大鹏 潘海洋[4] 刘邦先[3] 张平萍[1] 杨新华 

机构地区：[1]中钢集团郑州金属制品研究院有限公司,河南郑州450001 [2]华中科技大学土木工程与力学学院,湖北武汉430074 [3]郑州职业技术学院机械工程系,河南郑州450121 [4]郑州职业技术学院城市轨道交通系,河南郑州450121

出　　处：《武汉科技大学学报》2017年第5期395-400,共6页Journal of Wuhan University of Science and Technology

基　　金：国家自然科学基金重大研究计划项目(91016026);河南省博士后科研资助项目(博士后编号:166053)

摘　　要：综合考虑疲劳作用应力、三维塑性区域边界上的交变正应力与交变剪应力,利用二阶摄动方法建立了计算疲劳载荷作用下三维弹塑性弯曲裂纹尖端张开位移的理论模型。用数值解法进行求解,并作图分析了三维弹塑性弯曲裂纹尖端张开位移的最大值和变化幅值与三维裂纹体几何尺寸及外载荷之间的变化关系。结果表明,随着裂纹体厚度的增大,三维弹塑性弯曲裂纹尖端张开位移的最大值与变化幅值不断减小;当裂纹体几何尺寸相同时,弯曲裂纹尖端张开位移的最大值与变化幅值均随外载荷的增加而逐渐增大。Taking the effects of fatigue stress,cyclic normal and shear stresses on the boundaries of three dimensional plastic area into consideration,this paper has built the theoretical models to calculate three dimensional elastic-plastic curved crack tip opening displacement（CCTOD）under fatigue loads by using second order perturbation method.Numerical solutions were made,and the relation curves between the maximum or amplitude of CCTOD and the crack body geometrical dimensions as well as the external loads were analyzed.The results show that the maximum and amplitude of CCTOD decline with the increase of crack body thickness.When crack bodies have the same size,the maximum and amplitude of CCTOD increase with increasing external loads.

关 键 词：三维裂纹体 弯曲裂纹 张开位移 疲劳荷载 二阶摄动方法 

分 类 号：TB301[一般工业技术—材料科学与工程]