The role of plastic strain gradients in the crack growth resistance of metals
File(s)
Accepted version
Author(s)
Martinez-Paneda, Emilio
Deshpande, Vikram S
Niordson, Christian F
Fleck, Norman A
Type
Journal Article
Abstract
Crack advance from short or long pre-cracks is predicted by the progressive failure of a cohesive zone in a strain gradient, elasto-plastic solid. The presence of strain gradients leads to the existence of an elastic zone at the tip of a stationary crack, for both the long crack and the short crack cases. This is in sharp contrast with previous asymptotic analyses of gradient solids, where elastic strains were neglected. The presence of an elastic singularity at the crack tip generates stresses which are sufficiently high to activate quasi-cleavage. For the long crack case, crack growth resistance curves are predicted for a wide range of ratios of cohesive zone strength to yield strength. Remarkably, this feature of an elastic singularity is preserved for short cracks, leading to a severe reduction in tensile ductility. In qualitative terms, these predictions resemble those of discrete dislocation calculations, including the concept of a dislocation-free zone at the crack tip.
Date Issued
2019-05-01
Date Acceptance
2019-02-10
Citation
Journal of the Mechanics and Physics of Solids, 2019, 126, pp.136-150
ISSN
0022-5096
Publisher
Elsevier
Start Page
136
End Page
150
Journal / Book Title
Journal of the Mechanics and Physics of Solids
Volume
126
Copyright Statement
© 2019 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000464090900008&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Technology
Physical Sciences
Materials Science, Multidisciplinary
Mechanics
Physics, Condensed Matter
Materials Science
Physics
Strain gradient plasticity
Length scales
Cohesive zone modelling
Finite element analysis
Fracture
FINITE-ELEMENT
TIP FIELDS
PART I
FRACTURE
WORK
DEFORMATION
INDENTATION
DIFFUSION
Publication Status
Published
Date Publish Online
2019-02-12