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Title: Modelling of Local Necking and Fracture in Aluminium Alloys

Abstract

Non-linear Finite Element simulations are extensively used in forming and crashworthiness studies of automotive components and structures in which fracture need to be controlled. For thin-walled ductile materials, the fracture-related phenomena that must be properly represented are thinning instability, ductile fracture and through-thickness shear instability. Proper representation of the fracture process relies on the accuracy of constitutive and fracture models and their parameters that need to be calibrated through well defined experiments. The present study focuses on local necking and fracture which is of high industrial importance, and uses a phenomenological criterion for modelling fracture in aluminium alloys. As an accurate description of plastic anisotropy is important, advanced phenomenological constitutive equations based on the yield criterion YLD2000/YLD2003 are used. Uniaxial tensile tests and disc compression tests are performed for identification of the constitutive model parameters. Ductile fracture is described by the Cockcroft-Latham fracture criterion and an in-plane shear tests is performed to identify the fracture parameter. The reason is that in a well designed in-plane shear test no thinning instability should occur and it thus gives more direct information about the phenomenon of ductile fracture. Numerical simulations have been performed using a user-defined material model implemented in the general-purpose non-linearmore » FE code LS-DYNA. The applicability of the model is demonstrated by correlating the predicted and experimental response in the in-plane shear tests and additional plane strain tension tests.« less

Authors:
 [1];  [2];  [3];  [2];  [4]
  1. Structural Design, Offshore Construction Engineering, SUBSEA7, NO-4056 Tananger (Norway)
  2. SINTEF Materials and chemistry, Applied mechanics and corrosion, NO-7465 Trondheim (Norway)
  3. SIMLab, Department of Structural Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim (Norway)
  4. (Norway)
Publication Date:
OSTI Identifier:
21057338
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 908; Journal Issue: 1; Conference: NUMIFORM '07: 9. international conference on numerical methods in industrial forming processes, Porto (Portugal), 17-21 Jun 2007; Other Information: DOI: 10.1063/1.2740797; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM ALLOYS; ANISOTROPY; COMPRESSION; COMPUTERIZED SIMULATION; DUCTILITY; FINITE ELEMENT METHOD; FRACTURES; L CODES; NONLINEAR PROBLEMS; SHEAR; STRAINS; STRESSES; TESTING

Citation Formats

Achani, D., Eriksson, M., Hopperstad, O. S., Lademo, O.-G., and SIMLab, Department of Structural Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim. Modelling of Local Necking and Fracture in Aluminium Alloys. United States: N. p., 2007. Web. doi:10.1063/1.2740797.
Achani, D., Eriksson, M., Hopperstad, O. S., Lademo, O.-G., & SIMLab, Department of Structural Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim. Modelling of Local Necking and Fracture in Aluminium Alloys. United States. doi:10.1063/1.2740797.
Achani, D., Eriksson, M., Hopperstad, O. S., Lademo, O.-G., and SIMLab, Department of Structural Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim. Thu . "Modelling of Local Necking and Fracture in Aluminium Alloys". United States. doi:10.1063/1.2740797.
@article{osti_21057338,
title = {Modelling of Local Necking and Fracture in Aluminium Alloys},
author = {Achani, D. and Eriksson, M. and Hopperstad, O. S. and Lademo, O.-G. and SIMLab, Department of Structural Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim},
abstractNote = {Non-linear Finite Element simulations are extensively used in forming and crashworthiness studies of automotive components and structures in which fracture need to be controlled. For thin-walled ductile materials, the fracture-related phenomena that must be properly represented are thinning instability, ductile fracture and through-thickness shear instability. Proper representation of the fracture process relies on the accuracy of constitutive and fracture models and their parameters that need to be calibrated through well defined experiments. The present study focuses on local necking and fracture which is of high industrial importance, and uses a phenomenological criterion for modelling fracture in aluminium alloys. As an accurate description of plastic anisotropy is important, advanced phenomenological constitutive equations based on the yield criterion YLD2000/YLD2003 are used. Uniaxial tensile tests and disc compression tests are performed for identification of the constitutive model parameters. Ductile fracture is described by the Cockcroft-Latham fracture criterion and an in-plane shear tests is performed to identify the fracture parameter. The reason is that in a well designed in-plane shear test no thinning instability should occur and it thus gives more direct information about the phenomenon of ductile fracture. Numerical simulations have been performed using a user-defined material model implemented in the general-purpose non-linear FE code LS-DYNA. The applicability of the model is demonstrated by correlating the predicted and experimental response in the in-plane shear tests and additional plane strain tension tests.},
doi = {10.1063/1.2740797},
journal = {AIP Conference Proceedings},
number = 1,
volume = 908,
place = {United States},
year = {Thu May 17 00:00:00 EDT 2007},
month = {Thu May 17 00:00:00 EDT 2007}
}