A Simplified Orthotopic Viscoplasticity Theory Based on Overstress

  • M. Sutcu
  • E. Krempl
Conference paper


A small strain, unified theory is formulated without yield surfaces and loading/unloading conditions. It contains one tensor valued state variable for which an orthotropic growth law is formulated. Rate sensitivity, creep, relaxation as well as tension/compression asymmetry can be reproduced. A special selection of the material constants permits the modeling of elastic behavior in one direction with viscoplastic behavior in directions perpendicular to it.


Elastic Behavior Equilibrium Stress Rensselaer Polytechnic Institute Viscosity Function NASA Lewis Research 
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  1. 1.
    M. Sutcu, “An Orthotropic Formulation of the Viscoplasticity Theory Based on Overstress,” PhD Thesis, Rensselaer Polytechnic Institute, Troy, New York, December 1985.Google Scholar
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Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • M. Sutcu
    • 1
  • E. Krempl
    • 1
  1. 1.Mechanics of Materials LaboratoryRensselaer Polytechnic InstituteTroyUSA

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