异种热处理状态2219铝合金T字接头熔合区微气孔控制及其对焊缝性能的影响  

Control of Micro-pores in the Fusion Zone of Dissimilar Heat Treatment State 2219 Aluminum Alloy T-Joints and Its Impact on Weld Seam Performance

作　　者：孙文亮 赵刚 杨君 张文韬 米海明 刘紫阳 刘涛 SUN Wenliang;ZHAO Gang;YANG Jun;ZHANG Wentao;MI Haiming;LIU Ziyang;LIU Tao(Capital Aerospace Machinery Co.,Ltd.,Beijing 100076,China)

机构地区：[1]首都航天机械有限公司,北京100076

出　　处：《电焊机》2025年第3期96-102,共7页Electric Welding Machine

摘　　要：2219铝合金焊接过程中易出现气孔缺陷,尤其是在T字接头区域,不仅降低了接头的力学性能,也可能导致结构的失效。本研究针对C10S和CYS状态的2219铝合金,采用氦弧打底和氩弧盖面单面双层焊工艺试验,系统研究了T字接头的微气孔控制及其对焊缝性能的影响。试验结果表明,T字接头的近熔合区容易产生密集微气孔,这些微气孔对接头的抗拉强度具有显著影响。拉伸试验发现,T字接头的断裂位置集中在CYS侧,密集微气孔加剧了CYS侧的断裂倾向,使有密集微气孔的T字接头抗拉强度比无密集微气孔的接头低10~15 MPa。通过X射线无损检测和扫描电镜分析,发现这些微气孔主要是由于液态铝中氢的溶解度差异引起的氢气孔。进一步研究表明,优化焊接工艺参数,特别是增加氩弧盖面焊电流10~15 A,可有效抑制熔合区密集微气孔的产生。这种工艺改进通过扩大熔池体积和延长氢气排出时间,减少气孔缺陷,提高了接头力学性能。研究结果说明,通过合理调整焊接参数,可以有效提升铝合金结构的焊接质量和力学性能,满足铝合金压力容器高可靠性场合的实际需求。2219 aluminum alloy is prone to porosity defects during welding,particularly in the T-joint region,which not only reduces the mechanical properties of the joint but may also lead to structural failure.This study investigates the control of micropores in T-joints and their effect on weld properties,using C10S and CYS state 2219 aluminum alloy plates with a helium arc backing and argon arc double-layer welding process.The results show that the area near the weld pool in the Tjoint is susceptible to dense micropores,which significantly affect the tensile strength of the joint.Tensile tests revealed that fractures consistently occurred on the CYS side,with dense micropores exacerbating the tendency for fracture on the CYS side,resulting in a 10~15 MPa reduction in the ultimate tensile strength of T-joints with dense micropores compared to those without.X-ray non-destructive testing and scanning electron microscopy analysis indicated that these micropores are primarily hydrogen pores caused by the significant difference in hydrogen solubility between liquid and solid aluminum.Further research demonstrated that optimizing welding parameters,particularly increasing the argon arc welding current by 10~15 A,can effectively suppress the formation of dense micropores in the weld pool.This improvement,achieved by enlarging the weld pool and extending the time for hydrogen evasion,reduced porosity defects and enhanced the mechanical properties of the joint.The findings indicate that reasonable adjustments to welding parameters can effectively improve the quality and mechanical performance of aluminum alloy welds,meeting the high-reliability requirements of Aluminum alloy pressure vessel.

关 键 词：2219铝合金 氦弧打底 氩弧盖面 力学性能 熔合区 密集微气孔 

分 类 号：TG457.14[金属学及工艺—焊接]