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Title: Formulation of anisotropic Hill criteria for the description of an aluminium alloy behaviour during the channel die compression test

Abstract

During the last years the study of the plastic deformation modes and the anisotropic mechanical behaviour of aluminium alloys have been the subject of many investigations. This paper deals with a phenomenological identification of an anisotropic Hill constitutive equation of aluminium AU4G samples using a channel die compression device at room temperature. By considering the different possible orientations of the samples in the channel die device, three initial textures, named ND (normal direction Z), LD (longitudinal direction X) and TD (transverse direction Y), were defined with the corresponding stresses {sigma}ND, {sigma}LD and {sigma}TD. To describe the anisotropy of the material, a quadratic Hill criteria is used. An Avrami type equation based on the mixture of the hardening and softening phenomena is used to describe variation of each stress component with the equivalent plastic strain. The identification of the parameters of the law is made using an identification software (OPTPAR) and a good correlation between the experimental stresses and computed ones is obtained. The variation of the Hill parameters with a proposed equivalent strain, describing the deformation history of the material, is analysed. Finally, using the expressions of F, G, H and N, the constitutive equation of the normal anisotropy inmore » the plane XY is obtained.« less

Authors:
 [1];  [2]
  1. LGCGM (EA 3913), INSA de RENNES, 20, Av. des Buttes de Coeesmes, 35043, Rennes (France)
  2. SCR/CM-INSA (UMR CNRS 6226), INSA DE RENNES (France)
Publication Date:
OSTI Identifier:
21057027
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 907; Journal Issue: 1; Conference: 10. ESAFORM conference on material forming, Zaragoza (Spain), 18-20 Apr 2007; Other Information: DOI: 10.1063/1.2729532; (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; ALUMINIUM ALLOYS; ANISOTROPY; COMPRESSION; CORRELATIONS; DEFORMATION; HARDENING; MIXTURES; O CODES; ORIENTATION; PLASTICITY; STRAINS; STRESSES; TESTING; TEXTURE; VARIATIONS

Citation Formats

Gavrus, A., and Francillette, H.. Formulation of anisotropic Hill criteria for the description of an aluminium alloy behaviour during the channel die compression test. United States: N. p., 2007. Web. doi:10.1063/1.2729532.
Gavrus, A., & Francillette, H.. Formulation of anisotropic Hill criteria for the description of an aluminium alloy behaviour during the channel die compression test. United States. doi:10.1063/1.2729532.
Gavrus, A., and Francillette, H.. Sat . "Formulation of anisotropic Hill criteria for the description of an aluminium alloy behaviour during the channel die compression test". United States. doi:10.1063/1.2729532.
@article{osti_21057027,
title = {Formulation of anisotropic Hill criteria for the description of an aluminium alloy behaviour during the channel die compression test},
author = {Gavrus, A. and Francillette, H.},
abstractNote = {During the last years the study of the plastic deformation modes and the anisotropic mechanical behaviour of aluminium alloys have been the subject of many investigations. This paper deals with a phenomenological identification of an anisotropic Hill constitutive equation of aluminium AU4G samples using a channel die compression device at room temperature. By considering the different possible orientations of the samples in the channel die device, three initial textures, named ND (normal direction Z), LD (longitudinal direction X) and TD (transverse direction Y), were defined with the corresponding stresses {sigma}ND, {sigma}LD and {sigma}TD. To describe the anisotropy of the material, a quadratic Hill criteria is used. An Avrami type equation based on the mixture of the hardening and softening phenomena is used to describe variation of each stress component with the equivalent plastic strain. The identification of the parameters of the law is made using an identification software (OPTPAR) and a good correlation between the experimental stresses and computed ones is obtained. The variation of the Hill parameters with a proposed equivalent strain, describing the deformation history of the material, is analysed. Finally, using the expressions of F, G, H and N, the constitutive equation of the normal anisotropy in the plane XY is obtained.},
doi = {10.1063/1.2729532},
journal = {AIP Conference Proceedings},
number = 1,
volume = 907,
place = {United States},
year = {Sat Apr 07 00:00:00 EDT 2007},
month = {Sat Apr 07 00:00:00 EDT 2007}
}
  • The room temperature fatigue properties of AZ91 magnesium alloy produced by high pressure die casting (HPDC) as cast, heat treated, friction stir processed (FSP) and FSP and heat treated were studied. The fatigue properties of the material were evaluated for the HPDC magnesium alloy in the as-received state and after a solution treatment at 415 deg. C for 2 h and an ageing treatment at 220 deg. C for 4 h. The heat treatment resulted in a significant increase in the fatigue properties of the HPDC material, while no significance influence of heat treatment was recorded in the FSP condition.more » The morphology of fracture surfaces was examined by employing a field emission gun scanning electron microscope (FEGSEM)« less
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