|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Environmentally Assisted Cracking: Theory and Practice
||The Role of Hydrogen-enhanced Strain-induced Lattice Defects on Hydrogen Embrittlement Susceptibility of X80 Pipeline Steel
||Moeko Hattori, Hiroshi Suzuki, Kenichi Takai, Yusuke Seko
|On-Site Speaker (Planned)
The associated factors which lead to hydrogen embrittlement have not been fully clarified yet for ferrite/bainite X80 pipeline steel. Hydrogen embrittlement susceptibility was evaluated based on fracture strain in tensile testing. Tracer hydrogen content corresponding to the amount of lattice defects was measured by a thermal desorption analysis. Hydrogen embrittlement susceptibility and the amount of tracer hydrogen significantly increased with decreasing crosshead speed. In addition, the rate of formation of hydrogen-enhanced strain-induced lattice defects became maximum immediately before its final fracture. Fracture surface of the hydrogen-charged specimen exhibited shallower dimples without nucleuses such as second phase particles compared with hydrogen-free specimen. These findings indicate that hydrogen enhances formation of the lattice defects especially just before final fracture occurred, which enhance to form shallower dimples, and probably cause the premature fracture of X80 pipeline steel at lower crosshead speeds.
||Planned: Supplemental Proceedings volume