An effective method for determining necking and fracture strains of sheet metals
File(s)
Published version
Author(s)
Zhang, Ruiqiang
Shi, Zhusheng
Shao, Zhutao
Yardley, Victoria
Lin, Jianguo
Type
Journal Article
Abstract
Biaxial tensile testing methods using cruciform specimens have been developed in the last few decades for the determination of forming limit diagrams (FLDs) and fracture forming limit diagrams (FFLDs) for sheet metals. One of the difficulties associated with this test geometry is the lack of a widely accepted method to determine the necking and fracture strains which are necessary to construct these diagrams. In this study, a novel spatio-temporal method has been proposed for the determination of necking and fracture strains. In the method, two rectangular zones: the base zone (BZ) and the reference zone (RZ) are selected at the location where fracture initiates. The zone RZ includes the zone BZ and both zones have the same side length in the direction parallel to the necking band but different side length in the perpendicular direction. By plotting the thickness reduction within RZ against that in BZ, the onset of localised necking can be determined by finding the intersection of the two straight lines fitted separately using the data in the initial and final stages of deformation. The corresponding limit strains are then determined using the strains within the zone BZ. The method has been successfully applied to uniaxial tensile tests on AA6082 and boron steel dog-bone specimens, and to equi-biaxial tensile tests on AA5754 cruciform specimens.
Date Issued
2021-01-18
Date Acceptance
2021-01-13
Citation
MethodsX, 2021, 8
ISSN
2215-0161
Publisher
Elsevier
Journal / Book Title
MethodsX
Volume
8
Copyright Statement
©2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
License URL
Sponsor
Engineering & Physical Science Research Council (E
Grant Number
EP/R001715/1 / PO 2105860
Subjects
0912 Materials Engineering
Publication Status
Published
Article Number
ARTN 101234
Date Publish Online
2021-01-18