摘要
为建立适用于多晶金属钢疲劳裂纹萌生与短裂纹扩展的数值分析方法,基于Roe-Siegmund循环内聚力本构及Voronoi图法生成具有疲劳累计损伤特性的微观晶粒组织模型,同时考虑晶粒微观层面的力学特性,赋予各晶粒随机局部坐标系及各向异性线弹性常数,最后研究了气孔、夹杂等微观缺陷对裂纹萌生路径及寿命的影响。结果表明:上述方法在裂纹萌生路径上符合实际情况,存在穿晶及沿晶两种断裂模式并以后者为主,能够获取符合正态分布的裂纹萌生寿命范围值,并与文献试验结果相吻合;气孔及夹杂附件萌生出裂纹并与主裂纹汇合,影响裂纹萌生路径并改变裂纹萌生寿命。
In order to establish a numerical analysis method for fatigue crack initiation and short crack propagation in polycrystalline steels,a microstructure model with cumulative fatigue damage was generated based on Roe-Siegmund cyclic cohesive zone model and Voronoi diagram method,and the mechanical properties of grains at the microscopic level were considered.Each grain was assigned a random local coordinate system and an anisotropic linear elastic constitutive.Finally,the effects of the microscopic defects such as pores and inclusions on the crack initiation path and life were studied.The results show that the method is consistent with the actual situation in the crack initiation path,and there are two fracture modes,transgranular and intergranular,with the latter being the dominant one.The crack initiation life range values in accordance with the normal distribution can be obtained,which is consistent with the experimental in the literature.The crack initiation path and the life of the crack initiation are changed.
作者
赵秋
唐琨
吴维青
李英豪
邓俊逸
陈鹏
ZHAO Qiu;TANG Kun;WU Weiqing;LI Yinghao;DENG Junyi;CHEN Peng(College of Civil Engineering,Fuzhou University,Fuzhou 350116,China;Fujian College Association Instrumental Analysis Center,Fuzhou University,Fuzhou 350116,China)
出处
《机械科学与技术》
北大核心
2025年第2期361-372,共12页
Mechanical Science and Technology for Aerospace Engineering
基金
国家自然科学基金项目(51478120)。
