Dependence of hydrogen embrittlement on annealing time in medium-Mn steels

Abstract

Purpose

The purpose of this paper is to investigate the effect of the soft annealing time on the microstructure and hydrogen embrittlement (HE) of Fe-0.22C-11.54Mn-2.05Al steels.

Design/methodology/approach

Steels A and B with different morphologies were prepared by cold rolling after warm rolling, long/short softening annealing and finally annealing at 700 °C for 30 min. Uncharged and charged samples were subjected to tensile, and HE behavior was studied by electron backscattered diffraction, scanning electron microscopy and X-ray diffraction.

Findings

The two samples exhibited similar tensile strengths. The homogeneous equiaxed microstructure of steel B was found to be more conducive to relieve its HE sensitivity. Steel A exhibited bimodal-grained microstructures – blocky and lath. The formation of crack in the blocky grains of steel A resulted in a significant reduction in its plasticity and tensile strength.

Originality/value

The high HE susceptibility of steel A is mainly connected with the inhomogeneity of martensite transformation.

Citation

Xu, J., Li, J., Wang, Z., Fu, H. and Wu, M. (2021), "Dependence of hydrogen embrittlement on annealing time in medium-Mn steels", Anti-Corrosion Methods and Materials, Vol. 68 No. 5, pp. 464-472. https://doi.org/10.1108/ACMM-07-2021-2521