Simulation of primary dendrite arm spacing in an Al–Cu welding molten pool

Abstract

Primary dendrite arm spacing in tungsten inert gas welding pool for Al–4wt%Cu alloys is predicted by a quantitative phase-field model. Transient conditions are obtained by functions of thermal gradient and solidification rate. When the same welding power is given by 3500 W and different welding velocities are given by 1.5, 2.0 and 2.5 mm s⁻¹, the primary dendrite arm spacing obtained by simulation results is the largest under the welding velocity of 2.0 mm s⁻¹. When the same welding velocity is given by 2.5 mm s⁻¹ and different welding power is given by 3500, 4000 and 5000 W, the primary dendrite arm spacing acquired by simulation results is the largest under the welding power of 5000 W. Primary dendrite arm spacing and morphology obtained by simulation results agrees well with experimental findings.