Numerical modelling of thermal quantities for improving remote laser welding process capability space with consideration to beam oscillation

Abstract

This research aims to explore the impact of welding process parameters and beam oscillation on weld thermal cycle during laser welding. A three-dimensional heat transfer model is developed to simulate the welding process, based on finite element method. The results obtained from the model pertaining to thermal cycle and weld morphology are in good agreement with experimental results found in the literature. The developed heat transfer model can quantify the effect of welding process parameters (i.e. heat source power, welding speed, radius of oscillation, and frequecy of oscillation) on the intermediate performance indicators (IPIs) (i.e. peak temperature, heat-affected zone (HAZ) volume, and cooling rate). Parametric contour maps for peak temperature, HAZ volume, and cooling rate are developed for the estimation of the process capability space. An integrated approach for rapid process assessment, and process capability space refinement, based on IPIs is proposed. The process capability space will guide the identification of the initial welding process parameters window and helps in reducing the number of experiments required by refining the process parameters based on the interactions with the IPIs. Among the IPIs, the peak temperature indicates the mode of welding while the HAZ volume and cooling rate represent weld quality. The regression relationship between the welding process parameters and the IPIs is established for quick estimation of IPIs to replace time-consuming numerical simulations. The application of beam oscillation widens the process capability space, making the process parameter selection more flexible due to the increase in distance from the tolerance boundaries.

An Inhomogeneous Model for Laser Welding of Industrial Interest

“…5) deriving from a Gaussian heat distribution. This allowed the following formulations to be used [Mohan et al 2022]:…”

“…Further, to make the approach more realistic, boundary conditions -due to both contact with the air and contact with the workbench -have been added for the surfaces in question, finally achieving Cauchy-Stefan-Boltzmann boundary conditions. Once verified that the proposed model is well-posed (via hypothesis testing of a well-known result of the recent literature [Miranville et al 2021]) and reinforced by the fact that it does not allow the explicit recovery of T (x, t), an optimized Galerkin-FEM approach (to reduce the computational load useful for any real-time applications) has been implemented in MatLab R2022 PDE Tool and tested for the resolution of the problem by also selecting appropriate formulations of laser heat source, according with known experimental evidence [Mohan et al 2022].…”

Numerical study of beam oscillation and its effect on the solidification parameters and grain morphology in remote laser welding of high-strength aluminium alloys

“…The numerical study is based on our previously developed laser welding model [12][13][14][15] which is described by the solutions of mass, momentum, and energy conservation equations [16]. The difference within this study lies in the definition of the laser heat distribution from the volumetric and hybrid heat sources.…”

Investigation of the Effect of Heat Transfer during Friction Stir Welding (FSW) of AZ80A Mg Alloy Plates using a Pin Tool by Conducting Finite Elements Analysis

“…They did this by constructing joints out of AZ31 and AZ91 respectively [20]. It was revealed that joints with a certain distribution of phase grain architectures were generated in the middle of the stir zone when the tool was spun at 1400 revolutions per minute and the traverse rate was set to 25 millimeters per minute [21,22]. The setting for the traverse rate was 25 millimeters per minute.…”