低功率激光诱导电弧复合焊接钛合金薄板工艺研究

采用低功率脉冲YAG激光诱导非熔化极惰性气体保护(Tungsten inert gas,TIG)焊电弧复合热源实现了1 mm厚TC4钛合金薄板的优质焊接,研究激光诱导电弧复合焊接过程中热源能量匹配、热源间角度、对接间隙对焊缝成形的影响规律。结果表明,钛合金薄板低功率脉冲YAG激光诱导TIG电弧复合热源焊接过程中,激光能量与电弧能量之间的相互匹配将显著影响焊缝的表面成形。相对于电弧功率的变化,焊缝成形对激光功率变化的敏感度更高。随着热源间角度减小,激光诱导电弧复合热源传热能力增强;由于复合焊接速度快、热输入小、焊接试板横向变形小,当对接间隙为0~0.5 mm范围内时均能获得良好的焊缝成形。为了使焊缝成形均匀连续,焊接过程中需要对焊缝背面采用氩气进行保护,当保护气体流量为5~8L/min时获得最佳焊接接头。

Research on the Low Power Laser Induced Arc Hybrid Welding of Titanium Alloy Thinsheet

Butt welding of TC4 titanium alloy sheet with thickness of 1 mm is realized by pulsed YAG laser induced tungsten inert gas(TIG) arc hybrid welding technology. The influences of parameters on the hybrid welding shape are studied, which are including the energy cooperation between laser and arc, butt joint gap and heat source angle. The results of experiments show that the energy cooperation between laser and arc would make obviously effect on the weld appearance in laser induced TIG arc hybrid welding process. In comparison to variation of arc power, the weld appearance is more susceptible to variation of laser power. As heat source angle decreases, thermal conductivity of hybrid source grows. Since high welding speed, little thermal input and small deformation, the laser induced TIG hybrid welding process can obtain the perfect weld appearance at the butt joint gap among 0-0.5 mm. In order to get the ideal joint, the back of the specimen should be protected by the Ar gas. When the protective gas flow is 5-8 L/min, the favorable performance can be obtained.