Finite element analysis of heat flow in dual-beam laser welded tailored blanks

A two-dimensional moving adaptive finite element analysis is presented for dual beam laser welded tailored blanks. The simulation results show that welding with a dual-beam system to induce preheating reduces cooling rates effectively. For example, at 650° C, 1 mm away from the weld centerline, the cooling rates are calculated to be 421°C/sec and 428°C/sec in the thick (2 mm) and thin (0.8 mm) blanks, respectively, for a welding speed of 5 cm/sec and beam power of 1000 W on mild steel. For the same welding conditions, but with a preheating power of 1000 W and inter-beam spacing 1 cm, the cooling rates reduce to 228°C/sec and 240°C/sec in the thick and thin blanks, respectively.