焊接参数对2024铝合金FSW接头组织及腐蚀行为的影响  

Effect of Processing Parameters on Microstructure and Corrosion Behavior of Friction Stir Welded 2024 Aluminum Alloy

作　　者：康举[1] 梁苏莹[2] 李光[1] 栾国红[1] 董春林[1] 何淼[1] 付瑞东[3] 

机构地区：[1]北京航空制造工程研究所中国搅拌摩擦焊中心,北京100024 [2]首钢工学院,北京100144 [3]燕山大学亚稳材料制备技术与科学国家重点实验室,秦皇岛066004

出　　处：《腐蚀科学与防护技术》2012年第1期51-56,共6页Corrosion Science and Protection Technology

基　　金：航空科学重点基金项目(2009ZE25007)资助

摘　　要：对2024铝合金板进行不同参数下搅拌摩擦焊接,分析了焊缝表面组织.检查了在EXCO溶液中焊缝表面的腐蚀行为,并讨论硬度分布与腐蚀发生的关系.结果表明,焊后轴肩作用区晶粒细化明显.随转速的增加,焊缝上表面热影响区范围加宽、轴肩作用区硬度上升、耐蚀性能提高.在转速1500 r/min、行进速度1000mm/min下所得焊缝金属塑性流动剧烈.轴肩作用区硬度值已接近母材的硬度值,在EXCO溶液中浸泡10 h后仅发生点蚀.与母材相比,接头硬度的软化区是腐蚀发生的区域,但硬度值最低的位置与腐蚀最严重的区域没有严格的对应关系.Friction stir welding （FSW） for 2024 aluminum alloy sheets was conducted by different processing parameters. The microstructure of the surface and the corrosion behavior in EXCO solution of joints were investigated. The correlation between the micro-hardness profile and the corrosion sensitive region was discussed. The results show that grains in the shoulder active zone （SAZ） are obviously refined. With increasing the rotation speed, the spans of heat-affected zone （HAZ） widens, furthermore, the hardness of the SAZ increases and the corrosion resistance of this region enhances. When the rotation speed is 1500 r/rain and weld speed is 1000 mm/min, the plasticity metal flow is more intensive, and the hardness value of the SAZ comes up almost to that of-the base metal, therewith, only pitting corrosion occurred in the joint after being immersed 10 h in EXCO solution. Compared with the base metal, the softened zone coincides with the corrosion sensitive region. However, there is not strict correlation.

关 键 词：2024铝合金 搅拌摩擦焊 微观组织 显微硬度 浸泡试验 

分 类 号：TG172[金属学及工艺—金属表面处理]