Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403

공학

한국표면공학회지 (47권5호 257-262)

Hydrogen Embrittlement of 680 MPa DP sheet steel with Electrochemical Hydrogen charging conditions of Two Electrolytes

2종 전해질에서의 전기화학적 수소주입조건에 따른 680 MPa DP 박강판의 수소취성

박재우;강계명;
Park, Jae-Woo;Kang, Kae-Myung;

서울과학기술대학교 에너지환경대학원 신에너지공학과;서울과학기술대학교 신소재공학과;
Dept. of New Energy Engineering, Graduate School of Energy & Environment, Seoul National University of Science & Technology;Dept. of Materials Science & Engineering, Seoul National University of Science & Technology;

DOI : 10.5695/JKISE.2014.47.5.257

Abstract

In this paper, the behavior of hydrogen embrittlement of 680MPa DP sheet steel according to hydrogen charging conditions in acid and alkali electrolytes atmosphere was investigated. At this time, 0.5 M $H_2SO_4$ and 0.5M NaOH was used for electrolytes atmosphere and the effect on embrittlemnet of 680MPa DP sheet steel according to current density and charging time was evaluated by the change of subsurface microhardness in DP specimens chared hydrogen. As a result of this experiment, the microhardness of the layer directly below the surface was increased more than the microhardness of the subsurface zone in both electrolytes cases, but the change of the subsurface microhardness in both electrolytes was more affected by the increase of charging time than the increase of current density. The microhardness of subsurface zone in 0.5 M $H_2SO_4$ acid electrolyte was increased more than the microhardness in 0.5M NaOH alkali electrolyte. It was supposed that acid atmosphere was more sensitive to hydrogen embrittlement than alkali atmosphere on electrolyte atmosphere of hydrogen charge.

Keywords

hydrogen embrittlement;DP sheet steel;subsurface;electrolyte;