Direct Observation of Two-Dimensional Grain Boundary Sliding and Switching in ODS Ferritic Steel

Abstract:

High-temperature tensile deformation was performed using an oxide-dispersionstrengthened (ODS) ferritic steel,, which has grain structure largely elongated and aligned in one direction, in the perpendicular direction. In the superplastic region II, two-dimensional grain boundary sliding (GBS) was achieved, in which the material did not shrink in the grain-axis direction and grain-boundary steps appeared only in the surface perpendicular to the grain axis. In this condition, a classical grain switching event was observed. Using kernel average misorientation maps drawn with SEM/EBSD, dominant deformation mechanisms and accommodation processes for GBS were examined in the different regions. Cooperative grain boundary sliding, in which only some of grain boundaries slide, was also observed.

• Periodical: Materials Science Forum (Volumes 838-839)
• Pages: 43-50
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.838-839.43
• Online since: January 2016
• Authors: Eiichi Sato*, Hiroshi Masuda, Yoshito Sugino, Shigeharu Ukai
• Keywords: Core, Focused Ion Beam, Grain Boundary Sliding, Grain Switching, Mantle, Microgrid

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