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An uncoupled viscoplastic constitutive model for metals at elevated temperatureAn uncoupled constitutive model for predicting the transient response of thermal and rate dependent, inelastic material behavior is presented. The uncoupled model assumes that there is a temperature below which the total strain consists essentially of elastic and rate insensitive inelastic strains only. Above this temperature, the rate dependent inelastic strain (creep) dominates. The rate insensitive inelastic strain component is modeled in an incremental form with a yield function, flow rule and hardening law. Revisions to the hardening rule permit the model to predict temperature-dependent kinematic-isotropic hardening behavior, cyclic saturation, asymmetric stress-strain response upon stress reversal, and variable Bauschinger effect. The rate dependent inelastic strain component is modeled using a rate equation in terms of back stress, drag stress and exponent n as functions of temperature and strain. A sequence of hysteresis loops and relaxation tests are utilized to define the rate dependent inelastic strain rate. Evaluation of the model is performed by comparison with experiments involving various thermal and mechanical load histories on 5086 aluminum alloy, 304 stainless steel and Hastelloy-X.
Document ID
19830048580
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Haisler, W. E.
(Texas A&M Univ. College Station, TX, United States)
Cronenworth, J.
(Texas A & M University College Station, TX, United States)
Date Acquired
August 11, 2013
Publication Date
January 1, 1983
Subject Category
Structural Mechanics
Report/Patent Number
AIAA PAPER 83-1016
Meeting Information
Meeting: Structures, Structural Dynamics and Materials Conference
Location: Lake Tahoe, NV
Start Date: May 2, 1983
End Date: May 4, 1983
Accession Number
83A29798
Funding Number(s)
CONTRACT_GRANT: NAG3-31
Distribution Limits
Public
Copyright
Other

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