|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Ultrafine Grained Materials IX
||Hydrogen Diffusion in Ultrafine-Grained Iron Processed by High-Pressure Torsion
||Hideaki Iwaoka, Makoto Arita, Zenji Horita
|On-Site Speaker (Planned)
There is controversy as to whether the grain boundary in metallic materials acts as a trapping site or a fast diffusion path for hydrogen diffusion. Clear understanding has been prevented by the difficulty in producing bulk ultrafine-grained material. In the present study, High-Pressure Torsion (HPT) processing was used for grain refinement of metallic samples and hydrogen permeation tests were conducted electrochemically to investigate the grain boundary effect on hydrogen diffusion. Iron (99.99% purity) disks were prepared for electrochemical permeation tests after annealing, cold-rolling and HPT-processing. These disks were placed between two electrolytic cells; one is the cathode cell where hydrogen is generated on the disk surface by charging current and the other is the anode cell where permeating hydrogen is detected as permeating current. Permeation test shows the delay of hydrogen diffusion in HPT-processing disk compared to annealed and rolled disks.