中厚钛合金双脉冲TIG深熔焊接机制研究  

Deep Penetration Mechanism of Dual Pulse TIG Welding for Medium-Thick Titanium Alloys

作　　者：杨清福 罗志伟 曾才有 姜自昊 从保强[1] 齐铂金[1] Yang Qingfu;Luo Zhiwei;Zeng Caiyou;Jiang Zihao;Cong Baoqiang;Qi Bojin(School of Mechanical Engineering&Automation,Beihang University,Beijing 100191,China;Capital Aerospace Machinery Co.,Ltd,Beijing 100076,China)

机构地区：[1]北京航空航天大学机械工程及自动化学院,北京100191 [2]首都航天机械有限公司,北京100076

出　　处：《稀有金属材料与工程》2025年第3期688-696,共9页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(U20B2031,52075024)。

摘　　要：针对中厚度钛合金电弧焊存在的TIG电弧熔深浅和焊接效率低等问题,以6 mm厚TC4钛合金为焊接材料开展TIG焊接试验,研究了不同电弧模式(直流、低频脉冲、低频+超音频双脉冲)对熔池和焊缝成形的影响。基于有限元仿真研究了双脉冲焊接熔池的温度场和流场动态行为,探究了双脉冲TIG焊接深熔机制。结果表明,与恒流和低频脉冲模式相比,双脉冲电流模式增加了熔池熔体流动速度,能有效激发熔池中心深熔匙孔,促进热源下移,进而增大熔深。双脉冲TIG接头抗拉强度达到964 MPa,接头强度系数为98%,断后延伸率3.7%,可实现近等强接头强度匹配。In response to the issues of shallow TIG arc penetration and low welding efficiency in medium-thickness titanium alloy arc welding,TIG welding experiments were conducted on 6 mm-thick TC4 titanium alloy.The effects of different arc modes(direct current,low-frequency pulse,and low-frequency plus high-frequency dual-pulse)on the weld pool and weld bead formation were studied.Finite element simulation was employed to investigate the temperature field and flow field dynamics of the weld pool in dual-pulse welding,and the deep penetration mechanism of dual-pulse TIG welding was analyzed.The results show that compared to constant current and low-frequency pulse modes,the dualpulse current mode increases the flow velocity of the weld pool,effectively excites the deep penetration keyhole at the center of the pool,promotes the downward movement of the heat source,and thus increases the penetration depth.The tensile strength of the dual-pulse TIG weld joint reaches 964 MPa,the joint strength coefficient is 98%,and the post-fracture elongation is 3.7%,achieving a near-equal strength match for the joint.

关 键 词：中厚钛合金 TIG焊接 脉冲调制 深熔匙孔 微观组织 

分 类 号：TG146.23[一般工业技术—材料科学与工程]