70 0

The possibility of enhanced hydrogen embrittlement resistance of medium-Mn steels by addition of micro-alloying elements

Title
The possibility of enhanced hydrogen embrittlement resistance of medium-Mn steels by addition of micro-alloying elements
Author
한정호
Keywords
TRIP-assisted steel; Tensile behavior; Medium-Mn steel; Precipitation hardening; Hydrogen embrittlement; Ag decoration; Micro-alloying
Issue Date
2020-05
Publisher
ELSEVIER SCIENCE INC
Citation
MATERIALS CHARACTERIZATION, v. 165, article no. 110386
Abstract
In the present study, we elucidated the possibility of improvement in H embrittlement (HE) resistance of microalloyed medium-Mn steels by MC carbides formation. The Fe-6Mn-0.08C (wt%) steel was used as a base material, and the different amount of Nb, Ti, and V was added to form MC carbides. All steels exhibited the nano-sized globular morphology with dual-phase of alpha ferrite plus gamma(R) retained austenite, and the phase fraction was almost identical regardless of steel compositions. The steels showed an almost similar grain size of gamma(R) phase, regardless of composition. However, the micro-alloyed steel revealed the smaller size of alpha phase relative to base steel owing to MC carbides precipitation in the alpha phase. The micro-alloyed steel exhibited higher strength and lower ductility compared to the base material due to precipitation hardening and fine grain size of alpha. Considering HE resistance, we realized that the addition of the micro-alloying element resulted in a trivial effect on the medium-Mn steels, because MC carbides in the a phase could not act as influential trap sites of diffusible H. Most of the H atoms were preferentially trapped in the gamma(R) phase, and the H-enriched gamma(R) phase caused H-assisted nano crack when it transformed to strain-induced martensite. After that, the nano crack developed to the intergranular crack, leading to premature fracture.
URI
https://www.sciencedirect.com/science/article/pii/S1044580320308743?via%3Dihubhttps://repository.hanyang.ac.kr/handle/20.500.11754/166310
ISSN
1044-5803; 1873-4189
DOI
10.1016/j.matchar.2020.110386
Appears in Collections:
COLLEGE OF ENGINEERING[S](공과대학) > MATERIALS SCIENCE AND ENGINEERING(신소재공학부) > Articles
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE