The advantage of grain refinement in the hydrogen embrittlement of Fe-18Mn-0.6C twinning-induced plasticity steel

The effect of grain size on hydrogen embrittlement (HE) was investigated using Fe-18Mn-0.6C twinning-induced plasticity (TWIP) steel without Al through slow tensile tests and thermal desorption analyses. The grain refinement improved the resistance to HE of TWIP steel by suppressing a ductile to brittle transition. The high ductility of fine-grained specimens resulted from the low densities of twin boundaries, twin-twin junctions, and twin-grain boundary junctions, which are hydrogen-enriched during tensile tests, due to inactive mechanical twinning. (C) 2015 Elsevier Ltd. All rights reserved.