This study presents numerical analyses of the thermal, metallurgical, and mechanical processes involved in welding. The temperature fields were computed by solving the transient heat transfer equation using the ABAQUS/Standard 2024 finite element solver. Two types of moving heat sources were applied: a surface Gaussian distribution and a volumetric model, both implemented via DFLUX subroutines to simulate welding on butt-jointed plates. The simulation accounted for key welding parameters, including current, voltage, welding speed, and plate dimensions. The thermophysical properties of the INC 738 LC nickel superalloy were used in the model. Solidification characteristics, such as dendritic arm spacing, were estimated based on cooling rates around the weld pool. The model also calculated transverse residual stresses and applied a hot cracking criterion to identify regions vulnerable to cracking. The peak transverse stress, recorded in the heat-affected zone (HAZ), reached 1.1 GPa under Goldak’s heat input model. Additionally, distortions in the welded plates were evaluated for both heat source configurations.

In this paper we present an inverse finite element approach for the simulation of anisotropic tube hydroforming operation. This method exploits the knowledge of the final part shape, by starting from this later we search for the nodal positions in the initial cylindrical tube which verify the equilibrium of the final part. We propose a geometrical initial solution allows avoiding the problem of vertical walls and reverse taper. Two numerical applications concerning the hydroforming of T and Y-shaped tubes made from welded low carbon steel AISI 1008-galvanized, using the flow stress data obtained from bulge test have been utilized to validate the method. Verifications of the obtained results have been carried out using the classical explicit dynamic incremental approach (EDIA) by ABAQUS^® commercial code to show the efficiency of our approach.