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Title: Effective elastoplastic behavior of two-phase ductile matrix composites: Return mapping algorithm and finite element implementation

Abstract

Discrete numerical integration algorithm is employed to integrate rate equations in the effective elastoplastic model for particle reinforced ductile matrix composites based on probabilistic micromechanical formulations. In particular, the unconditionally stable implicit backward Euler integration algorithm is formulated for elastoplasticity of particle reinforced plastic matrix composites. In addition to the local integration algorithm, in nonlinear finite element methods for boundary value problems, tangent moduli are needed for the global Newton`s iterations. For this purpose, the continuum tangent operator based on the continuous rate equations is derived. In order to preserve the quadratic rate of convergence, the consistent tangent operator is constructed based on the proposed backward Euler integration algorithm. The elastoplastic model is further extended to accommodate the effect of viscosity in the matrix. The extension is based on the method of Duvaut-Lions viscoplasticity. The local integration algorithm and the consistent tangent operator are formulated for particle reinforced viscoplastic matrix composites. Numerical experiments are performed to assess the capability of the proposed integration algorithm and the convergence behavior of various tangent moduli.

Authors:
;  [1]
  1. Univ. of California, Los Angeles, CA (United States)
Publication Date:
OSTI Identifier:
175175
Report Number(s):
CONF-950686-
TRN: 95:006111-0091
Resource Type:
Conference
Resource Relation:
Conference: Joint applied mechanics and materials summer meeting, Los Angeles, CA (United States), 28-30 Jun 1995; Other Information: PBD: 1995; Related Information: Is Part Of AMD - MD `95: Summer conference; PB: 520 p.
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; COMPOSITE MATERIALS; MECHANICAL PROPERTIES; BOUNDARY-VALUE PROBLEMS; VISCOSITY; ELASTICITY; PLASTICITY; DUCTILITY

Citation Formats

Ju, J.W., and Tseng, K.H. Effective elastoplastic behavior of two-phase ductile matrix composites: Return mapping algorithm and finite element implementation. United States: N. p., 1995. Web.
Ju, J.W., & Tseng, K.H. Effective elastoplastic behavior of two-phase ductile matrix composites: Return mapping algorithm and finite element implementation. United States.
Ju, J.W., and Tseng, K.H. 1995. "Effective elastoplastic behavior of two-phase ductile matrix composites: Return mapping algorithm and finite element implementation". United States. doi:.
@article{osti_175175,
title = {Effective elastoplastic behavior of two-phase ductile matrix composites: Return mapping algorithm and finite element implementation},
author = {Ju, J.W. and Tseng, K.H.},
abstractNote = {Discrete numerical integration algorithm is employed to integrate rate equations in the effective elastoplastic model for particle reinforced ductile matrix composites based on probabilistic micromechanical formulations. In particular, the unconditionally stable implicit backward Euler integration algorithm is formulated for elastoplasticity of particle reinforced plastic matrix composites. In addition to the local integration algorithm, in nonlinear finite element methods for boundary value problems, tangent moduli are needed for the global Newton`s iterations. For this purpose, the continuum tangent operator based on the continuous rate equations is derived. In order to preserve the quadratic rate of convergence, the consistent tangent operator is constructed based on the proposed backward Euler integration algorithm. The elastoplastic model is further extended to accommodate the effect of viscosity in the matrix. The extension is based on the method of Duvaut-Lions viscoplasticity. The local integration algorithm and the consistent tangent operator are formulated for particle reinforced viscoplastic matrix composites. Numerical experiments are performed to assess the capability of the proposed integration algorithm and the convergence behavior of various tangent moduli.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1995,
month =
}

Conference:
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