Comparison of Hydrogen Embrittlement Susceptibility of Different Types of Advanced High-Strength Steels

oleh: Sangwon Cho, Geon-Il Kim, Sang-Jin Ko, Jin-Seok Yoo, Yeon-Seung Jung, Yun-Ha Yoo, Jung-Gu Kim

Format: Article
Diterbitkan: MDPI AG 2022-05-01

Deskripsi

This study investigated the hydrogen embrittlement (HE) characteristics of advanced high-strength steels (AHSSs). Two different types of AHSSs with a tensile strength of 1.2 GPa were investigated. Slow strain rate tests (SSRTs) were performed under various applied potentials (E<sub>app</sub>) to identify the mechanism with the greatest effect on the embrittlement of the specimens. The SSRT results revealed that, as the E<sub>app</sub> increased, the elongation tended to increase, even when a potential exceeding the corrosion potential was applied. Both types of AHSSs exhibited embrittled fracture behavior that was dominated by HE. The fractured SSRT specimens were subjected to a thermal desorption spectroscopy analysis, revealing that diffusible hydrogen was trapped mainly at the grain boundaries and dislocations (i.e., reversible hydrogen-trapping sites). The micro-analysis results revealed that the poor HE resistance of the specimens was attributed to the more reversible hydrogen-trapping sites.