Open AccessEvaluation of Simple Shear Test Geometries for Constitutive Characterization using Virtual Experiments
Author(s) -
Advaith Narayanan,
Armin Abedini,
A. Weinschenk,
M. J. Worswick,
Cliff Butcher
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1157/1/012066
Subject(s) - materials science , hardening (computing) , direct shear test , isotropy , shear (geology) , finite element method , simple shear , structural engineering , composite material , constitutive equation , digital image correlation , ultimate tensile strength , plane stress , tensile testing , mechanics , engineering , physics , optics , layer (electronics)
In-plane simple shear tests have become commonplace in the fracture characterization of automotive sheet metals but have received less attention for constitutive characterization. Unlike tensile tests, simple shear tests do not have any tensile instability and remain in a state of plane stress until fracture. From plastic work equivalence, an isotropic hardening model can be readily constructed from the tensile and shear test data without inverse finite-element analysis. The success of the methodology hinges upon the shear specimen geometry and how the local strains in the gage region are measured using digital image correlation (DIC). In this study, finite-element simulations of seven shear test geometries were evaluated for an isotropic material in a series of virtual experiments by varying the input hardening response. The data from the simulations was extracted from the surface as if DIC was employed and used to determine the hardening behavior in comparison with the exact solution. Shear geometries without a notch eccentricity in the gage region appear to be best suited for characterizing low hardening materials with an error of less than 1% in the stress response for an n-value of 0.02. Conversely, for higher hardening materials corresponding to an n-value of 0.20 or greater, the geometries with a notch eccentricity performed best.