Hydrogen diffusion in ultrafine-grained palladium: Roles of dislocations and grain boundaries

Hideaki Iwaoka, Makoto Arita, Zenji Horita

    Research output: Contribution to journalArticlepeer-review

    66 Citations (Scopus)


    Diffusion behavior of hydrogen in ultrafine-grained palladium (Pd) is investigated by electrochemical permeation tests. The ultrafine-grained structure is produced by severe plastic deformation through high-pressure torsion (HPT). The diffusion behavior is compared with an annealed state with a coarse-grained structure and a cold-rolled state with dislocations and subgrain structures. Hydrogen permeation is analyzed in absorption step and desorption step at five different temperatures in the range of 15-35°C. Hydrogen diffusion is retarded due to hydrogen trapping by dislocations. Grain boundaries act as rapid diffusion paths for hydrogen so that hydrogen diffusion is enhanced in the HPT-processed Pd samples with the ultrafine-grained structures.

    Original languageEnglish
    Pages (from-to)168-177
    Number of pages10
    JournalActa Materialia
    Publication statusPublished - Apr 1 2016

    All Science Journal Classification (ASJC) codes

    • Electronic, Optical and Magnetic Materials
    • Ceramics and Composites
    • Polymers and Plastics
    • Metals and Alloys


    Dive into the research topics of 'Hydrogen diffusion in ultrafine-grained palladium: Roles of dislocations and grain boundaries'. Together they form a unique fingerprint.

    Cite this