Enhancing hydrogen embrittlement resistance of a strip casting hot-stamping steel through vanadium microalloying

In this study, V-microalloying strip-cast hot-stamping steels with 0, 0.04, and 0.1 wt.% V were developed. Slow strain rate tensile tests indicated that V microalloying enhanced hydrogen embrittlement (HE) resistance, with the 0.1 wt.% V steel exhibiting a significant reduction in the HE index from 51.5% to 14.5%. Microstructural analysis revealed that V addition refined the prior austenite grain and promoted the formation of nanoscale VC precipitates which suppressed hydrogen-enhanced localized plasticity, thereby improving HE resistance. Thermal desorption spectroscopy demonstrated that VC precipitates act as irreversible hydrogen traps, reducing diffusible hydrogen concentration. This work provides insights into the role of V microalloying in enhancing the HE resistance of strip-cast hot-stamping steels.