Abstract
Laser welding is a modern welding process used to join similar and dissimilar metals. The laser beam has the highest energy concentration that melts the parts to be welded. Residual stress and cracks are produced due to the high temperature during the process which affects the fatigue life of the differential and ring gear assembly. The objective of this study is to predict the temperature, heat affected zone, residual stress and thermal distortion in the laser welding process using finite element Analysis. This analysis is a sequentially coupled thermomechanical analysis in which temperature result of thermal analysis is given as an input to structural analysis. A three dimensional finite element model is developed using commercially available code ABAQUS. Additionally numerical subroutine is created using FORTRAN language to implement the movable non-uniform heat source as the laser beam moves in circular path. Various aspects like radiation loss, convection loss, latent heat in the phase transformation and annealing effect are considered to capture the thermo-mechanical behaviour of the assembly and validated with test data. This analysis is done for the different influence of process parameters like laser power, laser beam diameter and welding speed. The current study is limited to thermal and structural effect during the laser welding process. Fusing and Solidification of metals are not considered and will be added in the future scope. The user subroutine is new and complex technique to achieve heat flux movement in circular path. The very high temperature, complicated geometry profile, element deletion and element activation make the FE analysis highly nonlinear.