|
authors |
Bintu, A; Vincze, G; Picu, CR; Lopes, AB; Gracio, JJ; Barlat, F |
|
nationality |
International |
|
journal |
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING |
|
author keywords |
TWIP steel; Mechanical behavior; Deformation twinning; Strain rate sensitivity |
|
keywords |
AUSTENITIC STEEL; DEFORMATION; MECHANISMS; ALLOYS; MODEL; GRAIN |
|
abstract |
TWIP steels are materials with very high strength and exceptional strain hardening capability, parameters leading to large energy absorption before failure. However, TWIP steels also exhibit reduced (often negative) strain rate sensitivity (SRS) which limits the post-necking deformation. In this study we demonstrate for an austenitic TWIP steel with 18% Mn a strong dependence of the twinning rate on the strain rate, which results in negative strain hardening rate sensitivity (SHRS). The instantaneous component of SHRS is large and negative, while its transient is close to zero. The SRS is observed to decrease with strain, becoming negative for larger strains. Direct observations of the strain rate dependence of the twinning rate are made using electron microscopy and electron backscatter diffraction, which substantiate the proposed mechanism for the observed negative SHRS. (C) 2015 Elsevier B.V. All rights reserved. |
|
publisher |
ELSEVIER SCIENCE SA |
|
issn |
0921-5093 |
|
year published |
2015 |
|
volume |
629 |
|
beginning page |
54 |
|
ending page |
59 |
|
digital object identifier (doi) |
10.1016/j.msea.2015.01.080 |
|
web of science category |
Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering |
|
subject category |
Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering |
|
unique article identifier |
WOS:000351795600007
|
