| Title |
Residual Stress Evolution Under Varying Process Parameters During L-DED of AISI 316L Stainless Steel Using Cantilever Beam Experiments and Finite Element Analysis |
| Authors |
정종욱(Jongwook Jung) ; 하경식(Kyeongsik Ha) ; 이욱진(Wookjin Lee) |
| DOI |
https://doi.org/10.3365/KJMM.2025.63.10.788 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
Additive manufacturing; L-DED; AISI 316L; FEM; Residual stress |
| Abstract |
Laser directed energy deposition (L-DED) is a metal additive manufacturing technique that
provides high design flexibility and enables the fabrication of complex geometries. However, the rapid and
localized thermal cycles inherent to the process lead to the formation of residual stresses, which degrade
mechanical properties and dimensional accuracy of the fabricated parts. In this study, the effect of L-DED
process parameters on residual stress formation was investigated using AISI 316L powder. Experiments were
conducted by depositing material onto substrates fixed at both ends, and bending deformation after constraint
removal was measured to evaluate the residual stress. The influences of key process parameters, including
laser power, scan speed, and scanning strategy, were systematically examined. A finite element method
(FEM) simulation based on the birth and death technique was developed to replicate the thermal and
mechanical behavior during the L-DED process. The simulation incorporated the temperature gradient
mechanism (TGM) and thermal strain of deposited layers to improve prediction accuracy. The FEM model
successfully reproduced the experimental trends, accurately predicting both the bending height and residual
stress distributions under various processing conditions. In particular, the model effectively captured the
influence of different scanning strategies on the stress profile, demonstrating its ability to simulate processinduced
thermal and mechanical behaviors with high fidelity. These findings provide a quantitative basis for
optimizing L-DED parameters and contribute to process design strategies aimed at minimizing residual stress
and enhancing dimensional stability in metal additive manufacturing. |