Laser-TIG electric arc hybrid welding technology for spaceflight aluminum alloy plate with medium thickness and high strength

Abstract

The invention discloses a laser-TIG electric arc hybrid welding technology for a spaceflight aluminum alloy plate with medium thickness and high strength and belongs to the technical field of weldingengineering. In the hybrid welding technology, a non-consumable TIG electric arc and laser beams emitted by a optical fiber laser are gathered at the same welding position on a workpiece along weldingdirection so as to jointly form a molten pool; when in welding, the laser beams are in the front and the non-consumable TIG electric arc is in the back; the distance form between the focus of the laser beams and the workpiece is sharp defocus, a dip angle between the laser beams and vertical direction is 15-17 degrees, the vertical distance from the tungsten electrode point end of the TIG electric arc to the surface of the workpiece is 3-5mm, the horizontal distances between the tungsten electrode point end of the TIG electric arc and from the laser beams to an action point on the surface ofthe workpiece are 3-5mm, and a dip angle between the tungsten electrode point end of the TIG electric arc and the horizontal direction of the workpiece is 45-55 degrees. The hybrid welding technologynot only improves the utilization ratio of laser energy, but also obviously enhances welding speed, and reduces metallurgical damage of a spaceflight aluminum alloy welding joint with high strength.

Description

technical field [0001] The invention relates to a high-efficiency and energy-saving welding technology of a composite heat source in the technical field of welding engineering, in particular to a laser-TIG arc composite welding process for medium-thick (4-8mm) aerospace high-strength aluminum alloy plates. Background technique [0002] Since the 1950s, aluminum-copper (Al-Cu) high-strength aluminum alloy materials have been used in large-scale aerospace welding structures, in which copper is used as a solid solution precipitation strengthening element in aluminum alloys, and other trace elements are dispersed in the form of intermetallic compounds. It mainly plays the role of controlling and inhibiting grain growth during recrystallization. Due to the characteristics of high reflectivity, large linear expansion coefficient and thermal conductivity, easy to produce refractory oxide film and high porosity of aerospace high-strength aluminum alloys and poor weldability, in the ...

AI Technical Summary

Problems solved by technology

Due to the characteristics of high reflectivity, large linear expansion coefficient and thermal conductivity, easy to produce refractory oxide film and high porosity of aerospace high-strength aluminum alloys and poor weldability, in the past 40 years, the tailor welding of its structure is still widely used TIG welding with filler wire process, but the inherent shortcomings of the process such as "low efficiency, energy consumption, large damage to materials, and low mechanical properties" have not been fundamentally resolved

[0004] But so far, laser-arc hybrid welding technology is using CO 2 , YAG laser and continuous TIG, MIG/MAG (melting electrode gas shielded welding), PAW (plasma arc welding), etc. through the paraxial or coaxia...

Images