Hydrogen embrittlement sensitivity of a novel cast high-strength multiphase stainless steel
Year: 2026
Type: article
Abstract: : This study explores the hydrogen embrittlement (HE) sensitivity of a novel cast high-strength multiphase stainless steel subjected to different heat treatments. Samples underwent solution treatment at 1050 °C followed by tempering at 610 °C (T610) and 650 °C (T650), and were then electrochemically hydrogen-charged. Mechanical testing combined with scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) was used to assess the effect of hydrogen on tensile properties and fracture behavior. The results show that hydrogen-induced degradation is closely related to the phase composition, particularly the amount of reverted austenite. The T650 sample, with 16.3% austenite, showed the lowest HE sensitivity (19.3%), whereas T610 with 9.6% austenite and the solution-treated S1050 with negligible austenite exhibited higher sensitivities of 43.4% and 58.3%. Microstructural analyses revealed that hydrogen preferentially accumulates and initiates cracks at elongated martensite/δ-ferrite interfaces (10–50 μm) and nanoscale Laves phase precipitates (~100 nm). Hydrogen promotes intergranular fracture and facilitates quasi-cleavage through the HELP mechanism, while strain-induced transformation of reverted austenite releases hydrogen that diffuses to crack tips and accelerates crack growth. By directly linking fine microstructural features (reverted austenite, δ-ferrite, and Laves phase) with macroscopic HE sensitivity and fracture behavior, this work provides new insights into the complex HE mechanisms of multiphase stainless steels and valuable guidance for designing hydrogen-resistant materials.
Authors: Jingyu He, Xu Wang, Guoqiang Liu, Zixiang Wu, Xiang Chen
Language: English
Subfield: Metals and Alloys
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,640
Award: G7576890977
OpenAlex ID: W7118511983