This paper takes a 4 mm-thick A7N01 aluminum alloy sheet as the research object and conducts simulations based on the laser-arc hybrid welding parameters of A7N01 aluminum alloy. Numerical simulations were performed using Fluent software to analyze the temperature field distribution and fluidity of the molten pool under different welding parameters

and to investigate how laser power and welding speed affect laser–arc hybrid welding. The results show that with the increase of laser power

the depth of the molten pool increases significantly. Meanwhile

the accelerated fluid flow speed inside the molten pool may enhance its instability. Although a higher welding speed can stabilize the molten pool in a shorter time

it is accompanied by a faster temperature change rate

which may lead to uneven cooling and the risk of cracking. On the contrary

a lower welding speed increases the heat input

resulting in a larger temperature gradient of the molten pool

which is conducive to forming a larger molten pool and deeper penetration. However

excessive heat input may also cause a series of welding defect problems.