Abstract
In this study, the ideal alloying element (among Cr, V, and Mo carbides) to enhance the resistance to hydrogen embrittlement (HE) in a tempered martensitic steel was investigated. Four types of steels were designed to contain cementites, Cr-rich M7C3 carbides, V carbides, and Mo carbides, respectively. These steels were tailored to possess a comparable tensile strength (~1.6 GPa). The HE resistances of these steels were evaluated through the slow strain rate test and cyclic corrosion test. The results showed an enhanced HE resistance, characterized by a high notch fracture strength after hydrogen charging, in the samples containing V carbides and Mo carbides. In particular, Mo carbide was regarded as the most ideal alloying element for HE resistance because of the high resistivity parameter, inhibited hydrogen penetration, and suppressed strength loss by internal hydrogen.
Highlights
High-strength steels have been actively developed in the steel industry to secure competitiveness in the market
These carbides were formed at right angles to each other owing to the Baker-Nutting orientation with a ferritic matrix (i.e. (001)VC//(001)α and [110]VC//[100]α)[16]
The results indicate an adverse impact of Cr-rich M7C3 carbides on the hydrogen embrittlement (HE) resistance of a tempered martensitic steel
Summary
High-strength steels have been actively developed in the steel industry to secure competitiveness in the market. Wei et al.[7,8,9,10,11] have conducted a series of valuable studies on this topic, related to the effect of Nb, Ti, and V carbides on HE characteristics According to their reports, these three types of carbides are nucleated at coherent interfaces in a nano-scale size. This study was aimed at investigating and comparing the effects of Cr, V, and Mo carbides on the HE resistance of a tempered martensitic steel. For this purpose, factors relevant to HE behavior other than carbides, Technology (POSTECH), Pohang, 37673, Korea. The microstructural evolution, hydrogen-trapping capability, and decrease in strength under two different HE conditions (i.e., cathodic precharging and cyclic corrosion test (CCT)) for four types of steels, were investigated
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
