Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting

Grain boundary engineering (GBE) is a thermomechanical processing strategy to enhance the physical and mechanical properties of polycrystalline metals by purposely incorporating special types of grain boundaries—such as twin boundaries (TB)—in the microstructure. Because of the multiple strain-annea...

Full description

Saved in:
Bibliographic Details
Main Authors: Gao, Shubo, Hu, Zhiheng, Duchamp, Martial, Krishnan, P. S. Sankara Rama, Tekumalla, Sravya, Song, Xu, Seita, Matteo
Other Authors: School of Mechanical and Aerospace Engineering
Format: Article
Language:English
Published: 2022
Subjects:
Online Access:https://hdl.handle.net/10356/160881
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Nanyang Technological University
Language: English
id sg-ntu-dr.10356-160881
record_format dspace
spelling sg-ntu-dr.10356-1608812022-08-13T20:11:59Z Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting Gao, Shubo Hu, Zhiheng Duchamp, Martial Krishnan, P. S. Sankara Rama Tekumalla, Sravya Song, Xu Seita, Matteo School of Mechanical and Aerospace Engineering School of Materials Science and Engineering Singapore Institute of Manufacturing Technology Engineering::Materials Selective Laser Melting Recrystallization Grain boundary engineering (GBE) is a thermomechanical processing strategy to enhance the physical and mechanical properties of polycrystalline metals by purposely incorporating special types of grain boundaries—such as twin boundaries (TB)—in the microstructure. Because of the multiple strain-annealing cycles involved, conventional GBE is not directly applicable to near-net-shape parts, such as those produced via additive manufacturing (AM) technology. In this study, we explore a different GBE processing route that leverages TB multiplication during recrystallization of austenitic 316L stainless steel produced via selective laser melting (SLM). We find that recrystallization requires a minimum level of mechanical deformation, which scales with the laser scanning speed employed during SLM. We ascribe this relationship to the cell size and the amount of solute segregating at cell boundaries during rapid solidification, which are inversely and directly proportional to the laser scanning speed, respectively. The coarser the cell structure and the more uniform the chemical composition, the easier the nucleation and growth of recrystallized grains. Our results provide the groundwork for devising AM-compatible GBE strategies to produce high-performance parts with complex geometry. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) Published version This research was funded by the National Research Foundation (NRF) Singapore, under the NRF Fellowship program (NRF-NRFF2018-05) and by the Agency for Science, Technology and Research (A*STAR), under the AME programmatic grant (SMAP, grant No A18B1b0061). 2022-08-05T03:25:19Z 2022-08-05T03:25:19Z 2020 Journal Article Gao, S., Hu, Z., Duchamp, M., Krishnan, P. S. S. R., Tekumalla, S., Song, X. & Seita, M. (2020). Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting. Acta Materialia, 200, 366-377. https://dx.doi.org/10.1016/j.actamat.2020.09.015 1359-6454 https://hdl.handle.net/10356/160881 10.1016/j.actamat.2020.09.015 2-s2.0-85091045956 200 366 377 en NRF-NRFF2018-05 A18B1b0061 Acta Materialia © 2020 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) application/pdf
institution Nanyang Technological University
building NTU Library
continent Asia
country Singapore
Singapore
content_provider NTU Library
collection DR-NTU
language English
topic Engineering::Materials
Selective Laser Melting
Recrystallization
spellingShingle Engineering::Materials
Selective Laser Melting
Recrystallization
Gao, Shubo
Hu, Zhiheng
Duchamp, Martial
Krishnan, P. S. Sankara Rama
Tekumalla, Sravya
Song, Xu
Seita, Matteo
Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting
description Grain boundary engineering (GBE) is a thermomechanical processing strategy to enhance the physical and mechanical properties of polycrystalline metals by purposely incorporating special types of grain boundaries—such as twin boundaries (TB)—in the microstructure. Because of the multiple strain-annealing cycles involved, conventional GBE is not directly applicable to near-net-shape parts, such as those produced via additive manufacturing (AM) technology. In this study, we explore a different GBE processing route that leverages TB multiplication during recrystallization of austenitic 316L stainless steel produced via selective laser melting (SLM). We find that recrystallization requires a minimum level of mechanical deformation, which scales with the laser scanning speed employed during SLM. We ascribe this relationship to the cell size and the amount of solute segregating at cell boundaries during rapid solidification, which are inversely and directly proportional to the laser scanning speed, respectively. The coarser the cell structure and the more uniform the chemical composition, the easier the nucleation and growth of recrystallized grains. Our results provide the groundwork for devising AM-compatible GBE strategies to produce high-performance parts with complex geometry.
author2 School of Mechanical and Aerospace Engineering
author_facet School of Mechanical and Aerospace Engineering
Gao, Shubo
Hu, Zhiheng
Duchamp, Martial
Krishnan, P. S. Sankara Rama
Tekumalla, Sravya
Song, Xu
Seita, Matteo
format Article
author Gao, Shubo
Hu, Zhiheng
Duchamp, Martial
Krishnan, P. S. Sankara Rama
Tekumalla, Sravya
Song, Xu
Seita, Matteo
author_sort Gao, Shubo
title Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting
title_short Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting
title_full Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting
title_fullStr Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting
title_full_unstemmed Recrystallization-based grain boundary engineering of 316L stainless steel produced via selective laser melting
title_sort recrystallization-based grain boundary engineering of 316l stainless steel produced via selective laser melting
publishDate 2022
url https://hdl.handle.net/10356/160881
_version_ 1743119536485302272