Effects of Thermomechanical Processing on Hydrogen Embrittlement Properties of UltraHigh-Strength TRIP-Aided Bainitic Ferrite Steels

Metals

Junya Kobayashi¹  Yoshito Takemoto²  Tomohiko Hojo³  Yutao Zhou³  Eiji Akiyama³  Saya Ajito³  Motomichi Koyama³  Akihiko Nagasaka⁴  Koh-ichi Sugimoto⁵ 

[1] College of Engineering, Ibaraki University, Hitachi 316-8511, Japan;Graduate School of National Science and Technology, Okayama University, Okayama 700-8530, Japan;Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan;National Institute of Technology, Nagano College, Nagano 381-8550, Japan;School of Science and Technology, Shinshu University, Nagano 380-8553, Japan;

关键词: TRIP-aided bainitic ferrite steel;    thermomechanical processing;    hydrogen embrittlement;    retained austenite;   

DOI  :  10.3390/met12020269

来源: DOAJ

【 摘 要 】

The effects of thermomechanical processing on the microstructure and hydrogen embrittlement properties of ultrahigh-strength, low-alloy, transformation-induced plasticity (TRIP)-aided bainitic ferrite (TBF) steels were investigated to apply to automobile forging parts such as engine and drivetrain parts. The hydrogen embrittlement properties were evaluated by conducting conventional tensile tests after hydrogen charging and constant load four-point bending tests with hydrogen charging. The 0.4 mass%C-TBF steel achieved refinement of the microstructure, improved retained austenite characteristics, and strengthening, owing to thermomechanical processing. This might be attributed to dynamic and static recrystallizations during thermomechanical processing in TBF steels. Moreover, the hydrogen embrittlement resistances were improved by the thermomechanical processing in TBF steels. This might be caused by the refinement of the microstructure, an increase in the stability of the retained austenite, and low hydrogen absorption of the thermomechanically processed TBF steels.

【 授权许可】

Unknown