Studies on weld shape formation and Marangoni convection in Nd:YAG laser welding

Abstract

Laser welding is a high energy beam welding process. Selection of process parameters is vital for the desired weld shape formation. Trial and error method for selection of appropriate process parameters prevailing in other welding processes is not suitable for laser welding. The effect of process parameters on the weld shape formation is analysed in this study with and without Marangoni convection. Finite volume method is adopted to study the heat transfer and fluid flow during the welding based on the solution of the equations of conservation of mass, momentum and energy in the weld pool. The studies are carried out on AISI 304 stainless steel of thickness 2 mm and its thermophysical properties are considered for the modelling and simulation. The simulated weld shape profiles are compared with the experimentally measured profile for different sets of welding parameters and all the simulated welds shapes are found to be in agreement.