Numerical Investigation of Laser Power Effects on Thermal Distribution and Melt Pool Morphology in Laser Powder Bed Fusion of 316L Stainless Steel

Year 2025, Volume: 11 Issue: 3, 481 - 494, 31.12.2025

Oğulcan Eren

Abstract

Laser Powder Bed Fusion (LPBF) is a widespread additive manufacturing method for precisely fabricating intricate metal parts. Despite its advantages, this process is highly sensitive to laser parameters, especially laser power, which determines the thermal behavior and the properties of the melt pool. In this study, transient finite element thermal analysis is presented to investigate the effect of varying laser power, quantified through Volumetric Energy Density (VED), on the temperature distribution and melt pool morphology in 316L stainless steel. This moving Gaussian laser transient thermal model implemented using Ansys Workbench was used to simulate single-track laser scanning. Unlike other complex finite element models, this simplified model is a practical tool that allows to predict thermal distribution in a computationally efficient manner. The results demonstrate that increasing VED leads to higher surface temperatures and deeper melt pools, transitioning from conduction-mode to keyhole-mode melting. Specifically, low VED conditions produced shallow melt pools that risk lack-of-fusion defects, while high VED resulted in geometries indicative of vaporization and keyhole instability. The research provides practical guidance on optimal power configurations and emphasizes the effectiveness of reduced-order thermal models for swift parametric analysis in LPBF.

Keywords

Laser Powder Bed Fusion (LPBF) , Finite Element Method (FEM) , Melt pool morphology , Thermal distribution , Additive manufacturing

Ethical Statement

The authors declare that there is no conflict of interest

Supporting Institution

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors..

Project Number

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

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