含紧固孔腐蚀长桁结构的疲劳裂纹扩展规律  

Fatigue Crack Growth Rule of Corroded Stringer Structure with Fastening Holes

作　　者：黎松 邹田春 LI Song;ZOU Tianchun(School of Safety Science and Engineering,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学安全科学与工程学院,天津300300

出　　处：《腐蚀与防护》2023年第7期52-57,63,共7页Corrosion & Protection

摘　　要：基于断裂力学的三维裂纹扩展理论解析法和FRANC3D软件的有限元仿真法,研究了含紧固件孔的腐蚀长桁结构在疲劳作用下的三维裂纹扩展规律。结果表明:有限元仿真的应力强度因子结果与理论解误差在5%以内,裂纹扩展寿命的误差在10%以内,验证了仿真模型的有效性。Ⅰ型裂纹最容易引起长桁结构发生脆性断裂,初始裂纹尺寸增加,应力强度因子和裂纹扩展速率也随之增加。裂纹扩展前期沿厚度方向,以小裂纹扩展为主,穿透后裂纹急速扩展,以长裂纹扩展为主。Based on the three-dimensional crack propagation theory of fracture mechanics and finite element simulation method of FRANC3D software,the three-dimensional crack propagation rule of corroded stringer structure with fastener holes under fatigue action was studied.The results showed that the error between the stress intensify factor(SIF)and the theoretical solution of finite element simulation was within 5%,and the error of the crack propagation life was within 10%,which verified the effectiveness of the simulation model.Type I cracks were most likely to cause brittle fractures in stringer structure.As the initial crack size increased,SIF and crack growth rate also increasd.In the early stage of crack propagation,small crack mainly propagated along the thickness direction.After penetration,the cracks propagated rapidly,mainly by long crack.

关 键 词：腐蚀 裂纹扩展 寿命 有限元 应力强度因子 

分 类 号：TG174[金属学及工艺—金属表面处理]