Abstract
In this study, a transient simulation of laser welding is carried out using Directed energy deposition (DED) method for the 4mm thick Inconel 901 plate. Experimental and numerical simulation method are used to investigate the thermal behavior and solidification characteristics. Five different cases are investigated using COMSOL Multiphysics® software. The parameters used in this study are the laser power ranging from 550 W to 750 W and the laser scanning speed ranging from 6.67 to 10.0 mm/s. The cooling time between the melting and solidification process is evaluated in the region under the top surface of substrate for different laser power and laser scanning speed. Among the cases studied, D5 shows the highest temperature variation under top the surface of the substrate, followed by D2, D3, D4, and D1 has the lowest temperature due to lower laser power. The temperature variation under the top surface of substrate is also calculated for different conditions of laser assisted DED processes. The numerical simulation results are compared with the experimental results which are in good agreement and well validated. The obtained conclusions in this paper demonstrated that this numerical study of thermal behavior could provide a better understanding of the melting and solidification process inside the molten pool using laser assisted DED processes.
