Scholarlink

<p>In a novel approach, the low-power pulsed laser-MIG hybrid welding (PLMW) technique is introduced for backing welding of medium-thick TC4 titanium alloy plates, aiming to overcome MIG welding drawbacks of unstable arc behavior and irregular weld formation. High-speed photography reveals that within the groove, the pulsed laser generates a high-temperature zone ahead of the molten pool, surpassing the thermionic emission temperature. This stabilizes the cathode spot position, suppresses arc and droplet deflection, thus effectively inhibiting weld inclination. The weld inclination angle β is reduced from 30 to 2°, effectively solving the backing weld inclination problem and producing a concave weld conducive to subsequent welding. Furthermore, the pulsed laser modifies the droplet dynamics by altering the force state: the proportion of one pulse multiple droplets transfer increases from 10 to 29%, and the transfer frequency rises from 258.1 to 303.5&#xa0;Hz, achieving uniform droplet transfer. Due to the enhanced molten pool fluidity of PLMW joints, pore defects are eliminated and grains are refined, thereby optimizing joint properties. Tensile tests confirm a joint strength of 965.5&#xa0;MPa and an elongation of 12.92%, representing a 20.5% increase, with the fracture mode shifting from mixed ductile–brittle to fully ductile. These findings confirm that the PLMW process, when applied to the backing welding of medium-thick titanium alloys, can achieve significant improvements in weld formation and mechanical properties while maintaining the high deposition rate of MIG welding.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Regulation mechanism of arc-droplet behavior and weld formation in low-power pulsed laser-MIG hybrid backing welding of medium-thick TC4 titanium alloy plates

  • 期刊论文

  • 发表日期：

    2026年4月11日

查看全文
  • Xinyuan Gong,
  • Zheyu Yang,
  • Zhaodong Zhang,
  • Qiang Lang,
  • Zhiwei Li,
  • Xueru Jiao,
  • Gang Song

摘要

In a novel approach, the low-power pulsed laser-MIG hybrid welding (PLMW) technique is introduced for backing welding of medium-thick TC4 titanium alloy plates, aiming to overcome MIG welding drawbacks of unstable arc behavior and irregular weld formation. High-speed photography reveals that within the groove, the pulsed laser generates a high-temperature zone ahead of the molten pool, surpassing the thermionic emission temperature. This stabilizes the cathode spot position, suppresses arc and droplet deflection, thus effectively inhibiting weld inclination. The weld inclination angle β is reduced from 30 to 2°, effectively solving the backing weld inclination problem and producing a concave weld conducive to subsequent welding. Furthermore, the pulsed laser modifies the droplet dynamics by altering the force state: the proportion of one pulse multiple droplets transfer increases from 10 to 29%, and the transfer frequency rises from 258.1 to 303.5 Hz, achieving uniform droplet transfer. Due to the enhanced molten pool fluidity of PLMW joints, pore defects are eliminated and grains are refined, thereby optimizing joint properties. Tensile tests confirm a joint strength of 965.5 MPa and an elongation of 12.92%, representing a 20.5% increase, with the fracture mode shifting from mixed ductile–brittle to fully ductile. These findings confirm that the PLMW process, when applied to the backing welding of medium-thick titanium alloys, can achieve significant improvements in weld formation and mechanical properties while maintaining the high deposition rate of MIG welding.