The invention relates to a
hybrid welding method of variable-polarity square-wave
tungsten electrode argon arc and
laser, comprising the following steps: firstly fixing a variable-polarity square-wave
tungsten electrode argon arc welding gun and a
laser beam transmitting gun, providing a workpiece moving at a
constant speed, forming a mode of preposing the variable-polarity square-wave
tungsten electrode argon arc welding gun, utilizing the
electric arc of variable-polarity square-wave
tungsten electrode argon
arc welding to remove impurities such as
oxide films and the like at the surface zone of the
welding workpiece, and leading the workpiece to be in a high-temperature melting state; and then leading
laser beams to radiate a welded part, thus deepening the depth of fusion in variable-polarity square-wave
tungsten electrode argon arc
welding and finishing the welding. By utilizing the welding method adopted by the invention, the
reflectivity of
metal to the laser can be reduced, and the absorptivity of the
metal to the laser energy is improved, so that the effective heating depth of the laser is improved, the depth of fusion of welding seams is enlarged, and the width of the welding seams and the width of heat affected zones are effectively reduced, thus finally a welding piece with deeper depth of fusion, very small heat affected zones and attractive appearance can be obtained.