焊接速度对BT-FSW 2219铝合金接头流动行为及组织与力学性能影响分析  

Effect of welding speed on material flow, microstructure and mechanical properties of BT-FSW 2219 aluminum alloy joints

作　　者：邹阳帆 李文亚[1] 褚强 苏宇[1] ZOU Yangfan;LI Wenya;CHU Qiang;SU Yu(State Key Laboratory of Solidification Processing,Shaanxi Key Laboratory of Friction Welding Technologies,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西省摩擦焊接工程技术重点实验室,西安710072

出　　处：《焊接学报》2022年第11期56-62,I0005,I0006,共9页Transactions of The China Welding Institution

基　　金：陕西省自然科学基金青年项目(2021JQ-102);上海航天科技创新基金(SAST2020-048);2021年西北工业大学博士论文创新基金(CX2021067)。

摘　　要：以4 mm厚2219-T87铝合金为研究对象,采用数值模拟和试验研究相结合的方法,研究了焊接速度对双轴肩搅拌摩擦焊接(BT-FSW)过程中金属流动行为、接头组织特征和力学性能的影响.模拟结果表明,随着焊接速度增加,焊缝高温区逐渐变窄,轴肩附近的材料流动减弱,而搅拌针附近的材料流动增强.试验结果表明,随着焊接速度增加,材料汇流区及S线缺陷均向前进侧(AS)靠近,焊接速度过大时AS附近的搅拌区(SZ)形成不连续组织.接头SZ的硬度值随着焊接速度增加而增大,而拉伸强度先增大后稍降低.当转速为300 r/min,焊接速度为150 mm/min时,接头获得最大的拉伸强度,为414 MPa±4MPa.The influence of welding speed on material flow,microstructure and mechanical properties of bobbin-tool FSW(BT-FSW) joints was analyzed by numerical simulation and experimental method on 2219-T87 aluminum alloy with the thickness of 4 mm. The simulation results show that the hightemperature zone of the joint became narrower with the increase of welding speed. The material flow near the shoulder was weakened, while the material flow near the pin was enhanced. The experimental results show that with the increase of welding speed, the material confluence zone and S line defects were closer to the advancing side(AS). However, the stirring zone(SZ) on the AS formed a discontinuous structure when the welding speed was too high. The hardness of SZ increased with the increase of welding speed, while the tensile strength increased first and then decreased slightly. When the welding speed was 150 mm/min and the rotation speed was 300 rpm, the maximum tensile strength of the joint was 414±4 MPa.

关 键 词：双轴肩搅拌摩擦焊接 焊接速度 2219铝合金 耦合欧拉-拉格朗日法 金属流动行为 力学性能 

分 类 号：TG453.9[金属学及工艺—焊接]