Hydrogen suppression of dislocation cell formation in micro and nano indentation of pure iron single crystals

TY - JOUR

T1 - Hydrogen suppression of dislocation cell formation in micro and nano indentation of pure iron single crystals

AU - Gong, Peng

AU - Katzarov, Ivaylo

AU - Nutter, John

AU - Paxton, Anthony T.

AU - Wynne, Bradley

AU - Rainforth, W. Mark

N1 - Funding Information: We acknowledge the support of EPSRC under the Programme Grant HEmS, EP/L014742 . I.H.K. acknowledges support from Bulgaria National Science Fund (BNSF) under Programme grant KP-06-H27/19 . Funding Information: We acknowledge the support of EPSRC under the Programme Grant HEmS, EP/L014742. I.H.K. acknowledges support from Bulgaria National Science Fund (BNSF) under Programme grant KP-06-H27/19. Publisher Copyright: © 2020 Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2021/3/15

Y1 - 2021/3/15

N2 - The influence of hydrogen on dislocation mobility in pure single crystal iron subjected to micro- and nanoindentation testing perpendicular to the (100) plane has been analysed using electron back-scattered diffraction (EBSD) and transmission electron microscopy (TEM) and simulated using the self-consistent kinetic Monte-Carlo (SCkMC) method. The nanoindentation load curve for the hydrogen free sample has two major constant load pop-ins, and multiple smaller pop-ins, whereas the hydrogen charged material has only one pop-in but with a longer loading release. A well-defined cell structure was observed below the indenter in the hydrogen free condition, but the dislocations were homogenously distributed in the hydrogen charged sample. The SCkMC simulations showed that it is difficult for dislocations to glide out of the primary slip plane after hydrogen charging compared with the hydrogen free sample under the present loading conditions.

AB - The influence of hydrogen on dislocation mobility in pure single crystal iron subjected to micro- and nanoindentation testing perpendicular to the (100) plane has been analysed using electron back-scattered diffraction (EBSD) and transmission electron microscopy (TEM) and simulated using the self-consistent kinetic Monte-Carlo (SCkMC) method. The nanoindentation load curve for the hydrogen free sample has two major constant load pop-ins, and multiple smaller pop-ins, whereas the hydrogen charged material has only one pop-in but with a longer loading release. A well-defined cell structure was observed below the indenter in the hydrogen free condition, but the dislocations were homogenously distributed in the hydrogen charged sample. The SCkMC simulations showed that it is difficult for dislocations to glide out of the primary slip plane after hydrogen charging compared with the hydrogen free sample under the present loading conditions.

KW - hydrogen induced softening

KW - micro- and nanoindentation

KW - Pure iron single crystal

KW - self-consistent kinetic Monte-Carlo (SCkMC) simulations

UR - http://www.scopus.com/inward/record.url?scp=85098175642&partnerID=8YFLogxK

U2 - 10.1016/j.scriptamat.2020.113683

DO - 10.1016/j.scriptamat.2020.113683

M3 - Article

AN - SCOPUS:85098175642

SN - 1359-6462

VL - 194

JO - SCRIPTA MATERIALIA

JF - SCRIPTA MATERIALIA

M1 - 113683

ER -