Chen-Nan Sun, Beng Loon Aw, Hengfeng Gu, Danny Ming Tak Choi, Chong Teng, Sharon Mui Ling Nai, Aravind Vasanthakumar, Chengcheng Wang,
Porosity distribution of 316 L stainless steel in laser powder bed fusion additive manufacturing due to spatial variation,
Journal of Manufacturing Processes,
Volume 139,
2025,
Pages 81-89,
ISSN 1526-6125,
https://doi.org/10.1016/j.jmapro.2025.02.031.
Abstract:
Laser powder bed fusion (LPBF) is at the forefront of the additive manufacturing industry due to its ability to
generate intricate and accurate objects layer-by-layer. However, maintaining low porosity (i.e., minimizing
defects) remains a significant challenge. This study investigates the influence of spatial variations on porosity,
independent of processing parameters, by fabricating SS316L cubes at various locations on the build platform
with both identical and varying processing parameters (laser power and scan speed). Changes in printing location
affect the incident angle between the surface normal and the laser, potentially leading to laser spot distortion and
altered effective energy input. This, in turn, can influence the porosity of the printed part. Additionally, improper
inert gas flow can hinder spatter removal, further increasing porosity. We demonstrate that, regardless of processing parameters, spatial variations on the build platform significantly impact porosity distribution. Our
findings, consistent with existing literature, highlight the importance of optimizing both build location and
processing parameters to achieve low porosity, particularly at the platform’s periphery. By analyzing the optimal
build locations and parameter combinations, this work provides valuable insights for LPBF practitioners seeking
to minimize porosity and improve printing outcomes at peripheral regions.
License type:
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Funding Info:
This research / project is supported by the A*STAR - RIE2020 Industry Alignment Fund – Industry Collaboration Projects
Grant Reference no. : I2001E0056