Open AccessLaser-TIG welding of galvanized steel – numerical and experimental assessment of the effect of arc in various setups
Author(s) -
Hana Šebestová,
Petr Horník,
Jan Novotný,
Libor Mrňa
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1135/1/012007
Subject(s) - gas tungsten arc welding , welding , materials science , galvanization , laser beam welding , metallurgy , arc welding , heat affected zone , gas metal arc welding , arc (geometry) , laser , coating , filler metal , composite material , mechanical engineering , optics , layer (electronics) , engineering , physics
The technology of laser-TIG welding utilizes the arc as a secondary heat source during laser welding. In TIG-leading configuration, the low-current arc precedes the beam to preheat the material. The numerical simulations representing various setups combining laser and arc were performed to study the changes of thermal cycles on the interface of thin metal sheets of overlap joint. The relations between the position of the arc towards the beam, additional heat input, and temperature gradients are discussed. The technology of laser-TIG welding of zinc-coated deep-drawing steel was experimentally applied in the same joint configuration. A good agreement between the calculated and experimental welds was achieved. The arc current less than 40 A did not cause the vaporization, neither oxidation of zinc coating on the interface surface of metal sheets. Nevertheless, the quality of laser-TIG welds was better compared to laser welds. The 40A arc current increased the heat input by about 50% and led to an almost 60% decrease in cooling rate compared to autonomous laser welding. Prolonged heating and cooling time are the key factors of improving the weld quality.