4D-STEM elastic stress state characterisation of a TWIP steel nanotwin
File(s)
Working paper
Author(s)
Type
Working Paper
Abstract
We measure the stress state in and around a deformation nanotwin in a
twinning-induced plasticity (TWIP) steel. Using four dimensional scanning
transmission electron microscopy (4D-STEM), we measure the elastic strain field
in a 68.2-by-83.1 nm area of interest with a scan step of 0.36 nm and a
diffraction limit resolution of 0.73 nm. The stress field in and surrounding
the twin matches the form expected from analytical theory and is on the order
of 15 GPa, close to the theoretical strength of the material. We infer that the
measured back-stress limits twin thickening, providing rationale for why TWIP
steel twins remain thin, continuously dividing grains to give substantial work
hardening. Our results support modern mechanistic understanding of the
influence of twinning on crack propagation and embrittlement in TWIP steels.
twinning-induced plasticity (TWIP) steel. Using four dimensional scanning
transmission electron microscopy (4D-STEM), we measure the elastic strain field
in a 68.2-by-83.1 nm area of interest with a scan step of 0.36 nm and a
diffraction limit resolution of 0.73 nm. The stress field in and surrounding
the twin matches the form expected from analytical theory and is on the order
of 15 GPa, close to the theoretical strength of the material. We infer that the
measured back-stress limits twin thickening, providing rationale for why TWIP
steel twins remain thin, continuously dividing grains to give substantial work
hardening. Our results support modern mechanistic understanding of the
influence of twinning on crack propagation and embrittlement in TWIP steels.
Date Issued
2020-04-08
Citation
2020
Publisher
arXiv
Copyright Statement
©2020 The Author(s)
Sponsor
Engineering & Physical Science Research Council (E
The Royal Society
Engineering & Physical Science Research Council (E
Identifier
http://arxiv.org/abs/2004.03982v1
Grant Number
EP/R511547/1
INF/R1/180085
138874
Subjects
cond-mat.mtrl-sci
cond-mat.mtrl-sci
Notes
As submitted for peer review
Publication Status
Published