Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1570561 | Materials Characterization | 2016 | 15 Pages |
Abstract
The work presents a detailed investigation of the microstructure characteristics of the ã111ã oriented grains in a Fe-30Ni-Nb austenitic model steel subjected to hot uniaxial compression at 925 °C at a strain rate of 1 sâ 1. The above grains exhibited a tendency to split into deformation bands having alternating orientations and largely separated by transition regions comprising arrays of closely spaced, extended sub-boundaries collectively accommodating large misorientations across very small distances. On a fine scale, the ã111ã oriented grains typically contained a mix of “microbands” (MBs) closely aligned with {111} slip planes and those significantly deviated from these planes. The above deformation substructure thus markedly differed from the microstructure type, comprising strictly non-{111} aligned MBs, expected within such grains on the basis of the uniaxial compression experiments performed using aluminium. Both the crystallographic MBs and their non-crystallographic counterparts typically displayed similar misorientations and formed self-screening arrays characterized by systematically alternating misorientations. The crystallographic MBs were exclusively aligned with {111} slip planes containing slip systems whose sum of Schmid factors was the largest among the four available slip planes. The corresponding boundaries appeared to mainly display either a large twist or a large tilt component.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
Debasis Poddar, Pavel Cizek, Hossein Beladi, Peter D. Hodgson,