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Title: Forming of Magnesium - Crystal Plasticity and Plastic Potentials

Abstract

Hexagonal close-packed (hcp) metals show a deformation behavior, which is quite different from that of materials with cubic crystalline structure. As a consequence, rolled or extruded products of magnesium and its alloys exhibit a strong anisotropy and an unlike yielding in tension and compression. Microstructural mechanisms of deformation in pure magnesium are modeled by constitutive equations of crystal plasticity. Single crystals and textured polycrystals are analyzed numerically. By means of virtual mechanical tests of representative volume elements mesoscopic yield surfaces are generated and compared with phenomenological yield surfaces. The hardening behavior as well as deformation kinematics are accounted while fitting the respective model parameters for a plane stress state. The linking of micro- and mesoscale provides a procedure for the simulation of the yielding and hardening behavior of arbitrarily textured solids with hcp structure such as extruded bars or rolled plates.

Authors:
; ;  [1]
  1. GKSS Research Center, Institute for Materials Research, Mechanics of Materials, Geesthacht (Germany)
Publication Date:
OSTI Identifier:
21056985
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: 10.1063/1.2729690; (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; ANISOTROPY; COMPARATIVE EVALUATIONS; COMPRESSION; COMPUTERIZED SIMULATION; DEFORMATION; HARDENING; HCP LATTICES; MAGNESIUM; MAGNESIUM ALLOYS; MECHANICAL TESTS; MICROSTRUCTURE; MONOCRYSTALS; PLASTICITY; POLYCRYSTALS; SOLIDS; STRESSES; SURFACES

Citation Formats

Steglich, Dirk, Graff, Stephane, and Brocks, Wolfgang. Forming of Magnesium - Crystal Plasticity and Plastic Potentials. United States: N. p., 2007. Web. doi:10.1063/1.2729690.
Steglich, Dirk, Graff, Stephane, & Brocks, Wolfgang. Forming of Magnesium - Crystal Plasticity and Plastic Potentials. United States. doi:10.1063/1.2729690.
Steglich, Dirk, Graff, Stephane, and Brocks, Wolfgang. Sat . "Forming of Magnesium - Crystal Plasticity and Plastic Potentials". United States. doi:10.1063/1.2729690.
@article{osti_21056985,
title = {Forming of Magnesium - Crystal Plasticity and Plastic Potentials},
author = {Steglich, Dirk and Graff, Stephane and Brocks, Wolfgang},
abstractNote = {Hexagonal close-packed (hcp) metals show a deformation behavior, which is quite different from that of materials with cubic crystalline structure. As a consequence, rolled or extruded products of magnesium and its alloys exhibit a strong anisotropy and an unlike yielding in tension and compression. Microstructural mechanisms of deformation in pure magnesium are modeled by constitutive equations of crystal plasticity. Single crystals and textured polycrystals are analyzed numerically. By means of virtual mechanical tests of representative volume elements mesoscopic yield surfaces are generated and compared with phenomenological yield surfaces. The hardening behavior as well as deformation kinematics are accounted while fitting the respective model parameters for a plane stress state. The linking of micro- and mesoscale provides a procedure for the simulation of the yielding and hardening behavior of arbitrarily textured solids with hcp structure such as extruded bars or rolled plates.},
doi = {10.1063/1.2729690},
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}
}
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