The effect of retained austenite (RA) with higher mechanical stability on hydrogen embrittlement resistance of a modified 22MnB5 (C 0.22, Si 0.8, Mn 1.5, B 0.002, Fe balance, in wt.%) press hardening steel (PHS) has been studied. One-step quenching and partitioning (Q&P) treatment was applied to PHS, and around 6 vol.% ultra-fine RA was obtained. The ultra-fine RA was found to act as stronger hydrogen trap than dislocations and grain boundaries in martensitic matrix and can decrease the apparent diffusion coefficient of hydrogen from 5.97 × 10^–7 to 3.83 × 10^–7 cm² s⁻¹, which was verified by the combination of thermal desorption spectroscopy analysis and hydrogen permeation test. The higher mechanical stability of the ultrafine RA assures enough stability of the hydrogen trap, which results in better hydrogen embrittlement resistance in Q&P-treated PHS than the conventional directly quenched PHS.

研究了具有较高机械稳定性的残余奥氏体 (RA) 对改性 22MnB5 (C 0.22, Si 0.8, Mn 1.5, B 0.002, Fe 平衡, 重量百分比) 冲压硬化钢 (PHS) 抗氢脆性的影响. 对 PHS 进行一步淬火和分配 (Q&P) 处理，获得了约 6 vol.% 的超细 RA。发现超细 RA 比马氏体基体中的位错和晶界具有更强的氢陷阱，可以将氢的表观扩散系数从 5.97 × 10 ^-7降低到 3.83 × 10 ^-7 cm ²  s ^-1, 通过热脱附光谱分析和氢渗透测试相结合的验证。超细 RA 更高的机械稳定性保证了氢阱的足够稳定性，这导致 Q&P 处理的 PHS 比传统的直接淬火 PHS 具有更好的抗氢脆性。