학술논문
전기화학적 및 고압 수소 분위기하 템퍼드 마르텐사이트강의 수소취화 특성 비교
Hydrogen Embrittlement Characteristics of Tempered Martensitic Steels under Electrochemical and High-Pressure Hydrogen Environments
Hydrogen Embrittlement Characteristics of Tempered Martensitic Steels under Electrochemical and High-Pressure Hydrogen Environments
Document Type
Article
Author
김상규 / Sang-gyu Kim; 김재윤 / Jae-yun Kim; 서현주 / Hyun-joo Seo; 정환교 / Hwan-gyo Jung; 박재영 / Jaeyoung Park; 백운봉 / Un-bong Baek; 황병철 / Byoungchul Hwang
Source
대한금속재료학회지 / Korean journal of metals and materials. Nov 05, 2023 61(11):807
Subject
Language
Korean
English
English
ISSN
1738-8228
Abstract
The effect of hydrogen charging methods on the hydrogen embrittlement characteristics of tempered martensitic steels were discussed in terms of hydrogen diffusion behavior. Two tempered martensitic steels with different Si content were fabricated by quenching and tempering. The steel with high Si content had a lower cementite fraction because the addition of Si changed the morphology of cementite from a long film-like shape to a short-rod shape by suppressing the precipitation and growth of the cementite. To evaluate the hydrogen embrittlement resistance of the two tempered martensitic steels with different Si content, slow strain-rate tensile testing was employed after introducing hydrogen using three types of hydrogen charging methods (ex-situ electrochemical hydrogen charging, in-situ electrochemical hydrogen charging, and in-situ high-pressure gaseous hydrogen environment). For the hydrogen pre-charged tensile specimens using the ex-situ electrochemical charging method, the steel with high Si content had a better hydrogen embrittlement resistance, with a higher relative reduction in area. On the other hand, there was no significant difference in the relative notch tensile strength of the two tempered martensitic steels with different Si content, regardless of the hydrogen charging methods. In addition, the ex-situ hydrogen charging method exhibited higher relative notch tensile strength compared to the in-situ hydrogen charging method due to the release of hydrogen during the tensile test, after exsitu hydrogen charging. This implies that hydrogen embrittlement resistance can be differently estimated depending on the kind of hydrogen charging methods. (Received 17 July, 2023; Accepted 24 August, 2023)