Effect of δ-ferrite on susceptibility to hydrogen embrittlement of 304 austenitic stainless steel in high-pressure hydrogen atmosphere

Abstract

Purpose

The purpose of this paper is to demonstrate the effect of δ-ferrite on the susceptibility to hydrogen embrittlement of type 304 stainless steel in hydrogen gas environment.

Design/methodology/approach

The mechanical properties of as-received and solution-treated specimens were investigated by the test of tensile and fatigue crack growth (FCG) in 5 MPa argon and hydrogen.

Findings

The presence of δ-ferrite reduced the relative elongation and the relative reduction area (H₂/Ar) of 304 stainless steel, indicating that δ-ferrite increased the susceptibility of hydrogen embrittlement in 304 stainless steel. Moreover, δ-ferrite promoted the fatigue crack initiation and propagation at the interface between δ-ferrite and austenite. The FCG tests were used to investigate the effect of δ-ferrite on the FCG rate in hydrogen gas environment, and it was found that δ-ferrite accelerated the FCG rate, which was attributed to rapid diffusion and accumulation of hydrogen around the fatigue crack tip through δ-ferrite in high-pressure hydrogen gas environment.

Originality/value

The dependence of the susceptibility to hydrogen embrittlement on δ-ferrite was first investigated in type 304 steel in hydrogen environment with high pressures, which provided the basis for the design and development of a high strength, hydrogen embrittle-resistant austenitic stainless steel.

Citation

Bao, F., Zhang, K., Zhou, Z., Zhang, W., Cai, X. and Zhang, L. (2021), "Effect of δ-ferrite on susceptibility to hydrogen embrittlement of 304 austenitic stainless steel in high-pressure hydrogen atmosphere", Anti-Corrosion Methods and Materials, Vol. 68 No. 3, pp. 202-208. https://doi.org/10.1108/ACMM-11-2020-2403