Title of article :
A new class of micro–macro models for elastic–viscoplastic heterogeneous materials
Author/Authors :
Hafid Sabar، نويسنده , , Marcel Berveiller، نويسنده , , Veronique Favier، نويسنده , , Stephane Berbenni، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2002
Abstract :
The determination of the effective behavior of heterogeneous materials from the properties of the components and
the microstructure constitutes a major task in the design of new materials and the modeling of their mechanical behavior.
In real heterogeneous materials, the simultaneous presence of instantaneous mechanisms (elasticity) and time
dependent ones (non-linear viscoplasticity) leads to a complex space–time coupling between the mechanical fields,
difficult to represent in a simple and efficient way. In this work, a new self-consistent model is proposed, starting from
the integral equation for a translated strain rate field. The chosen translated field is the (compatible) viscoplastic strain
rate of the (fictitious) viscoplastic heterogeneous medium submitted to a uniform (unknown) boundary condition. The
self-consistency condition allows to define these boundary conditions so that a relative simple and compact strain rate
concentration equation is obtained. This equation is explained in terms of interactions between an inclusion and a
matrix, which lead to interesting conclusions. The model is first applied to the case of two-phase composites with
isotropic, linear and incompressible viscoelastic properties. In that case, an exact self-consistent solution using the
Laplace–Carson transform is available. The agreement between both approaches appears quite good. Results for
elastic–viscoplastic BCC polycrystals are also presented and compared with results obtained from Kr€oner–Weng’s and
Paquin et al. (Arch. Appl. Mech. 69 (1999) 14)’s model
Keywords :
Heterogeneous Material , Integral equation , Elastic–viscoplastic material , Projection operators , Self-consistent approximation
Journal title :
International Journal of Solids and Structures
Journal title :
International Journal of Solids and Structures