康举 李吉超 冯志操 Frankel G.S. 王国庆 吴爱萍. 2219-T8铝合金搅拌摩擦焊接头 力学和应力腐蚀性能薄弱区研究[J]. 金属学报, DOI: 10.11900/0412.1961.2015.0201.

摘要 相关文章 Metrics 全文: PDF(1820 KB)   摘要: 对2219-T8铝合金搅拌摩擦焊 (FSW) 接头在拉伸过程中, 热机械影响区 (TMAZ) 的变形行为、断裂途径和190 MPa下微区电化学性能进行了研究. 研究表明, 焊接热循环和搅拌作用加权强化效果最弱的区域是强度最差的位置；拉伸时接头变形主要发生在TMAZ, 但由于受到焊核区的拘束程度不同, TMAZ下层应变更大, 导致裂纹起源于下层；在相同的应力水平下, TMAZ表面的钝化膜更易破裂, 甚至会有微裂纹出现, 这使得当接头处于应力腐蚀环境中时, TMAZ更易发生局部腐蚀, 导致接头的抗应力腐蚀能力下降. 关键词 ： 2219铝合金,  搅拌摩擦焊,  薄弱区,  微区电化学特性,  应力腐蚀,  原位拉伸观察     Abstract：Aluminum alloy 2219 (AA2219) is widely used in the aerospace industry, and friction stir welding (FSW) is an ideal method to join it. The ultimate tensile strength of a FSW AA2219-T8 joint can be as high as 344 MPa which is significantly higher than that welded by other methods such as gas tungsten arc welding. However, the thermo-mechanically affected zone (TMAZ) in the FSW joints of AA2219-T6/T8 is a weakness zone of mechanical property and is susceptible to stress corrosion cracking (SCC), but the reasons are not been well understood. In this work, the mechanical and electrochemical properties of different zones in AA2219-T8 joints obtained by the FSW method were studied. The welding thermal cycles during welding were measured using an array of type K thermocouples. During the tensile process of the joints, digital image correlation (DIC) technique and high speed video technique were employed to investigate the deformational behavior and fracture pathway of the TMAZ, respectively. A microcell method was used to study the micro-electrochemical characteristics of the joints with and without stress. The results showed that the minimum strength located at a position where the weighted strengthening effects of both thermal cycles and stir action were the weakest. The DIC results revealed that the deformation concentrated mainly in the TMAZ during the tensile tests. However, due to the different restraints from the nugget zone (NZ) led to a large strain in the root side than that in the crown side. This made the root side susceptible to cracks initiation. In situ tensile testing indicated that cracks occurred only in the TMAZ at 190 MPa, indicating that the protective surface films in the TMAZ were more prone to crack than those in other zones of the joint. This led the TMAZ to be the weakest zone to pitting corrosion in an aggressive environment. Once pits generate in the TMAZ, the local stress will concentrate near the tip of the pitting, resulting in failure. Key words： 2219 aluminum alloy    friction stir welding (FSW)    weakness zone    micro-electrochemical characteristics    stress corrosion cracking (SCC)    in situ tensile testing 收稿日期: 2015-04-07      服务 把本文推荐给朋友 加入引用管理器 E-mail Alert RSS 作者相关文章 康举 李吉超 冯志操 Frankel G.S. 王国庆 吴爱萍 44.8K 链接本文: https://www.ams.org.cn/CN/Y0/V/I/0 [1] 宋昱杉, 刘叡, 崔宇, 刘莉, 王福会. 静水压力和拉伸应力交互作用下Ni-Cr-Mo-V钢在3.5%NaCl溶液中的应力腐蚀行为[J]. 金属学报, 2025, 61(2): 309-322. [2] 徐玮辰, 佟向瑜, 王优强, 张斌斌, 马超群, 王秀通. 深海环境对钛合金应力腐蚀影响的研究进展[J]. 金属学报, 2025, 61(10): 1469-1484. [3] 徐洋, 柯黎明, 聂浩, 夏春, 刘强, 陈书锦. 局部强冷作用下厚板铝合金/镁合金搅拌摩擦焊界面金属间化合物的析出行为[J]. 金属学报, 2024, 60(6): 777-788. [4] 韩恩厚, 王俭秋. 表面状态对核电关键材料腐蚀和应力腐蚀的影响[J]. 金属学报, 2023, 59(4): 513-522. [5] 常立涛. 压水堆主回路高温水中奥氏体不锈钢加工表面的腐蚀与应力腐蚀裂纹萌生：研究进展及展望[J]. 金属学报, 2023, 59(2): 191-204. [6] 马志民, 邓运来, 刘佳, 刘胜胆, 刘洪雷. 淬火速率对7136铝合金应力腐蚀开裂敏感性的影响[J]. 金属学报, 2022, 58(9): 1118-1128. [7] 何长树, 郄默繁, 张志强, 赵骧. 轴向超声振动对搅拌摩擦焊过程中金属流动行为的影响[J]. 金属学报, 2021, 57(12): 1614-1626. [8] 刘晨曦, 毛春亮, 崔雷, 周晓胜, 余黎明, 刘永长. 低活化铁素体/马氏体钢组织调控及其固相连接研究进展[J]. 金属学报, 2021, 57(11): 1521-1538. [9] 刘振宝,梁剑雄,苏杰,王晓辉,孙永庆,王长军,杨志勇. 高强度不锈钢的研究及发展现状[J]. 金属学报, 2020, 56(4): 549-557. [10] 马宏驰, 杜翠薇, 刘智勇, 李永, 李晓刚. E690高强低合金钢焊接热影响区典型组织在含SO2海洋环境中的应力腐蚀行为对比研究[J]. 金属学报, 2019, 55(4): 469-479. [11] 邓平,孙晨,彭群家,韩恩厚,柯伟,焦治杰. 核用304不锈钢辐照促进应力腐蚀开裂研究[J]. 金属学报, 2019, 55(3): 349-361. [12] 张聪惠, 荣花, 宋国栋, 胡坤. 喷丸表面粗糙度对纯Ti焊接接头在HCl溶液中应力腐蚀开裂行为的影响[J]. 金属学报, 2019, 55(10): 1282-1290. [13] 王晨, 王贝贝, 薛鹏, 王东, 倪丁瑞, 陈礼清, 肖伯律, 马宗义. SiCp/6092Al复合材料搅拌摩擦焊接头的疲劳行为研究[J]. 金属学报, 2019, 55(1): 149-159. [14] 武传松, 宿浩, 石磊. 搅拌摩擦焊接产热传热过程与材料流动的数值模拟[J]. 金属学报, 2018, 54(2): 265-277. [15] 马宗义, 商乔, 倪丁瑞, 肖伯律. 镁合金搅拌摩擦焊接的研究现状与展望[J]. 金属学报, 2018, 54(11): 1597-1617. Viewed Full text Abstract Cited   Shared      Discussed