This paper discusses the avoidance of hydrogen embrittlement (HE) in a medium manganese stainless steel X20CrNiMnVN18-5-10. We adopted a HE-mitigation strategy that relies on improving its intrinsic resistance to hydrogen by adjusting an ultrafine microstructure (∼1.3 µm) containing a significant amount of nano-sized V- and Cr-based precipitates in the size range of 20 - ≥200 nm. The precipitation state was characterized using a high-resolution scanning transmission electron microscope. Slow strain rate tests at a strain rate of 10⁻⁶ s⁻¹ were conducted on specimens with/without hydrogen pre-charging to evaluate the HE susceptibility. Thermal desorption analysis was applied to explore the hydrogen trapping behavior in cold-rolled, annealed and hydrogen pre-charged states. Hydrogen uptake and hydrogen desorption behaviors show a dependence on the size of precipitates. It is remarked that the large precipitates trap a larger amount of hydrogen and show a higher temperature desorption peak than the small precipitates do. The high-temperature hydrogen desorption peaks (>400 °C) indicate that the observed nano-sized precipitates provide irreversible trapping sites, where hydrogen uptake occurs. The investigated steel X20CrNiMnVN18-5-10 demonstrates an enhanced intrinsic resistance to HE in comparison to medium and high manganese as well as stainless steels. The findings suggest that microstructure engineering with sufficient number of hydrogen traps in an ultrafine-grained microstructure is an appropriate HE mitigation strategy that allows designing hydrogen-resistant advanced high strength steels.

本文讨论了在中锰不锈钢X20CrNiMnVN18-5-10中避免氢脆（HE）的问题。我们采用了HE缓和策略，该策略依赖于通过调节超细微结构（〜1.3 µm）来提高其对氢的固有抵抗力，该超微结构包含大量的纳米级基于V和Cr的沉淀，粒径范围为20-≥200纳米 使用高分辨率扫描透射电子显微镜表征沉淀状态。应变速率为10 ^-6  s ^-1的慢应变速率测试在有/没有氢预充电的样品上进行实验，以评估HE的敏感性。应用热脱附分析来探索在冷轧，退火和氢预充电状态下的氢捕获行为。氢的吸收和氢的解吸行为显示出对沉淀物尺寸的依赖性。值得注意的是，大的沉淀物比小的沉淀物捕获更多的氢，并且显示出更高的温度解吸峰。高温氢解吸峰（> 400°C）表明，观察到的纳米级沉淀提供了不可逆的捕集位点，发生了氢吸收。与中，高锰以及不锈钢相比，所研究的X20CrNiMnVN18-5-10钢具有更高的HE固有抗性。