Fostering strengths against hydrogen embrittlement: insights from nanotwin-ability and post-treatment effects in additively manufactured CoCrFeMnNi

Autor: Renhao Wu, Soung Yeoul Ahn, Yeon Taek Choi, Hyojin Park, Man Jae SaGong, Ganesh Sattineni, Hyeonseok Kwon, Sang Guk Jeong, Gitaek Lee, Ho Hyeong Lee, Haiming Zhang, Hyoung Seop Kim
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Materials Research Letters, Vol 12, Iss 10, Pp 689-699 (2024)
Druh dokumentu: article
ISSN: 21663831
2166-3831
DOI: 10.1080/21663831.2024.2371521
Popis: This study delves into effects of deep cryogenic treatment (DCT) on enhancing the hydrogen embrittlement resistance of CoCrFeMnNi high-entropy alloy fabricated via laser powder-bed-fusion (L-PBF). Comparatively assessing as-print, conventional heat treatment, and DCT, we uncover how nanotwin formation within matrix serves as a critical mechanism to combat adverse effects of hydrogen embrittlement. This work reveals that DCT not only mitigates inherent residual stresses from L-PBF, thereby fostering dislocation redistribution and microstructural stabilization, but also synergizes with high-density dislocation cells. Our findings articulate a nuanced understanding of microstructural evolution in response to post-treatments and consequential enhancement of hydrogen embrittlement resistance.Highlights Laser-based additively manufactured CoCrFeMnNi undergoes post heat treatment and deep cryogenic treatment to tailor dislocations and residual stress.The inherent residual stress acts as the driving force for the redistribution of dislocations, leading to the development of a stable microstructure after deep cryogenic treatment.High-density dislocation cells and hydrogen collaborate to lower the local stacking fault energy, triggering gradient nanotwins.Nanotwin-ability effects by deep cryogenic treatment (77 K × 36 h) on the hydrogen embrittlement resistance of CoCrFeMnNi with interior defects are verified.
Databáze: Directory of Open Access Journals