The numerical simulation of heat transfer during a hybrid laser–MIG welding using equivalent heat source approach

• Heat transfer is simulated for hybrid laser arc welding in Y-shaped gap geometry.
• Exploratory design method is used to adjust the equivalent heat sources parameters.
• Melted zone dimensions are collected from experiment results using macrographs.
• Thermocouples measurements are compared with calculated thermograms.
• Good agreement between numerical and experimental results has been observed.

The present study is dedicated to the numerical simulation of an industrial case of hybrid laser–MIG welding of high thickness duplex steel UR2507Cu with Y-shaped chamfer geometry. It consists in simulation of heat transfer phenomena using heat equivalent source approach and implementing in finite element software COMSOL Multiphysics. A numerical exploratory designs method is used to identify the heat sources parameters in order to obtain a minimal required difference between the numerical results and the experiment which are the shape of the welded zone and the temperature evolution in different locations. The obtained results were found in good correspondence with experiment, both for melted zone shape and thermal history.