单个边缘微观损伤对铝合金材料蚀坑应力集中效应的影响研究  

Influence of Single Marginal Microcosmic Damage on Concentration Effect of Corrosion Pit Stress for Aluminum Alloy

作　　者：刘治国 李旭东 陈川 LIU Zhiguo;LI Xudong;CHEN Chuan(Naval Aeronautical University Qingdao Branch,Shandong Qingdao 266041,China)

机构地区：[1]海军航空大学青岛校区,山东青岛266041

出　　处：《机械科学与技术》2021年第3期456-462,共7页Mechanical Science and Technology for Aerospace Engineering

摘　　要：为获取边缘微观损伤对铝合金蚀坑产生的应力集中效应的影响及影响规律,采用ANSYS有限元方法,构建7B04铝合金半椭球体简化蚀坑模型、单个半椭球体包含一个边缘微观损伤的蚀坑模型,并基于线弹性断裂力学,开展两种蚀坑模型的应力集中效应计算分析。研究发现:边缘微观损伤对半椭球体蚀坑应力集中效应的数值大小、作用区域以及作用区域大小影响明显。包含与不包含边缘微观损伤的半椭球体蚀坑产生的应力集中系数最大值分别为K_(t,max)=3.359和K_(t,max)=2.24;包含边缘微观损伤的半椭球体蚀坑其应力集中效应明显的区域集中在边缘微观损伤与半椭球体蚀坑交汇位置的侧边;边缘微观损伤对点蚀损伤应力集中效应的影响与其表面尺寸、深度以及方位有关,应力集中系数随其深度与长度的比值(h/l)增加而增加,且K_(t,θ=45°)>K_(t,θ=0)。In order to obtain the influence rule of the marginal microcosmic damage to stress concentration effect of 7B04 aluminum alloy which caused by corrosion pits,ANASYS finite element method was adopted to erect two corrosion pits model,which respectively were semi-ellipsoid corrosion pit model and semi-ellipsoid corrosion pit model that including a marginal microcosmic damage,based on linear elastic fracture mechanics,stress concentration effect of two models was calculated and analyzed.Results show that marginal microcosmic damage has direct influence to stress concentration effect of corrosion pits through value of K_(t) and influence zone and influence zone size.Firstly,K_(t,max) value of two model was respectively 3.359 and 2.24.Secondly,obvious area of stress concentration effect of emi-ellipsoid corrosion pit model that including a marginal microcosmic damage located at the intersection region between marginal damage and ellipsoidal corrosion pit.Thirdly,the influence of marginal microcosmic damage to corrosion pit stress concentration effect was influenced by size and orientation of marginal microcosmic damage itself,K_(t) increased with h/l value increase,and usually K_(t,θ=45°)>K_(t,θ=0) at the same size condition of marginal microcosmic damage.

关 键 词：铝合金 应力集中 蚀坑 边缘微观损伤 影响分析 

分 类 号：TG174.3[金属学及工艺—金属表面处理] V216.5[金属学及工艺—金属学]