|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Advanced High Strength Steels V
||Methods for Improving the Hydrogen Embrittlement Resistance in Press-hardened Steel
||Zuoheng Cao, Xiaochuan Xiong, MingXin Huang
|On-Site Speaker (Planned)
Hydrogen embrittlement in high strength pressed-hardened steel (PHS) is a serious issue in the automotive industry. In particular, PHS with a tensile strength of 2 GPa is very sensitive to the defects in the microstructure. The present work shows that non-metallic inclusions such as oxides are the origin of hydrogen embrittlement during the slow strain rate test (SSRT) after electrochemically hydrogen charging. The typical fracture surface shows a fish-eye feature, similar to the fatigue failure in high strength steel. It indicates that the size and volume fraction of the non-metallic inclusions play a crucial role in determining the hydrogen embrittlement of PHS. It is recommended that ultra-clean steel manufacturing practice, similar to the one used for high-performance bearing steel, should be adopted for 2 GPa PHS for improvement of the hydrogen embrittlement resistance.