(中南大学 高性能复杂制造国家重点实验室，长沙 410083)
摘 要: 分别采用超声搅拌复合焊(USCW)和搅拌摩擦焊(FSW)对厚度为1.8 mm的2524-T3航空铝合金薄板进行对接焊试验，对比分析USCW和FSW接头的外观、性能和微观组织。结果表明：USCW接头质量优于搅拌摩擦焊的，焊缝稳定性比FSW焊缝的好，USCW可实现近零缺陷焊接，而FSW焊缝缺陷率达50%以上。显微组织分析结果表明：USCW焊核区晶粒较搅拌摩擦焊更加细小、均匀；USCW焊缝热机影响区与热影响区较FSW的小。通过对超声搅拌复合焊的机理分析发现，超声波的热效应、体积效应和强振动效应，具有补偿焊缝中底部热量、强化金属塑性流动、细化和均匀组织的效果。
关键字: 2524-T3铝合金；超声搅拌复合焊；搅拌摩擦焊；焊接稳定性
（State Key Laboratory of High Performance Complex Manufacturing, Central South University,
Changsha 410083, China）
Abstract:The joint appearance, properties and microstructure of 1.8 mm-thickness 2524-T3 aluminum alloy sheet in friction stirring welding and ultrasonic agitation compound welding were compared. The results show the joint quality and stability of USCW are better than those of the FSW. The USCW defect rate is nearly zero, while FSW defect rate is more than 50%. The microstructure analysis results show that the grain of USCW is smaller and more uniform than that of FSW. The heat-affected zone (HAZ) and thermo-mechanically-affected zone (TMAZ) of USCW is significantly reduced, compared to FSW. Through the mechanism analysis of USCW, the thermal effect, volume effect and strong vibration effect of ultrasonic wave can add the heat to the bottom of joint, strength metal plastic flow and refine, uniform organization.
Key words: 2524-T3 aluminum alloy; ultrasonic stir compound welding; friction stir welding; welding stability
