203323
20181203023704.0
09650393
10.1088/0965-0393/8/2/309
doi
ARTICLE
Parameter identification method for a polycrystalline viscoplastic selfconsistent model based on analytical derivatives of the direct model equations
2000
2000
Journal Articles
An inverse method for automatic identification of the parameters involved in a polycrystalline viscoplastic selfconsistent (VPSC) model is presented. The parameters of the constitutive viscoplastic law at the single-crystal level, i.e. the critical resolved shear stresses (CRSS) of slip and twinning and the micro-hardening coefficients, can be identified using experimental data at the polycrystal level, i.e. stress-strain curves and deformation-induced textures. The minimization problem is solved by means of a Gauss-Newton scheme and the sensitivity matrix is evaluated by analytical differentiation of the direct model equations. As a particular case, the optimization procedure for the Taylor full constraints (FC) formulation is also presented. The convergence and stability of the identification scheme are analysed using several validation tests for different deformation paths imposed to a polycrystal of hexagonal structure. As an example of application of this inverse method, the relative CRSS of the active deformation systems of a Zircaloy-4 sheet are identified, based on several textures measured for different reductions and rolling directions.
Computer simulation
Critical resolved shear stress
Deformation induced texture
Gauss-Newton scheme
Mathematical models
Plastic deformation
Polycrystalline materials
Polycrystalline viscoplastic selfconsistent model
Shear stress
Single crystals
Strain
Stresses
Stress strain curve
Taylor full constraint
Textures
Twinning
Viscoplasticity
Zirconium alloys
Signorelli, J.W.
LogĂ©, R.E.
243441
248074
Chastel, Y.B.
Lebensohn, R.A.
193-209
Modelling and Simulation in Materials Science and Engineering
8
LMTM
252516
U12903
oai:infoscience.tind.io:203323
article
STI
EPFL-ARTICLE-203323
OTHER
PUBLISHED
REVIEWED
ARTICLE