User login


You are here

ES 246 project: Planar Composite under Plastic Deformation

Xuanhe Zhao's picture

The mechanical performance of a homogeneous material can be varied by the addition of second-phase particles. In this project, we will model a planar composite under plastic deformation. As shown on the following figure, the composite consists of matrix material and randomly-distributed inclusion particles. The matrix is assumed to be an elastic-plastic material with isotropic or kinematic hardenings, and the inclusion particle pure elastic with a higher Young’s modulus. The stress/strain field throughout the composite will be calculated numerically with finite element method. The effective constitutive behavior of the composite will be evaluated and compared with theoretical and experimental results from literature [1, 2].

[1] Torquato, S.: Random heterogeneous media: microstructure and improved bounds on effective properties. Appl. Mech. Rev. 44, 37-75 (1991)
[2] Ponte Castaneda, P.: The effective mechanical properties of nonlinear isotropic composite. J. Mech. Phys. Solids 39, 45-71 (1991).

Image icon Figure 1 Plast.PNG132.97 KB
Office presentation icon report_ES246.ppt877 KB


Nanshu Lu's picture

It's an interesting topic related to the applications of piezoelectrical materials. To deal with random heterogeneous media I simply have two concerns,

1. In order to say random-distributed second-phase particles, one need to be careful of the geometric design. For example, the proportion of length scales of particle vs. matrix, the particle spacing and so on.

2.Besides the geometrical characteristics of multiphase materials, an important aspect is the contrast between the different constituent materials, such as Young's modulus. As far as plasticity is concerned The ranges spanned by the yield stress are from 20 MPa to more than 1 GPa for metals and alloys, from a few MPa to 150 MPa for polymers, 1 to 10 GPa for ceramics.

For details, please consult

Syntheses: Mechanical properties of heterogeneous media: Which material for which model? Which model for which material? P Gilormini et al 1999 Modelling Simul. Mater. Sci. Eng. 7 805-816


Kristin M. Myers's picture

This may fall out of the scope of your class project, but how does a micor-mechanical model compare to the discussed constitutive models you propose?

Time permitting, you can explore the results of the following paper:

Micromechanics, macromechanics and constitutive modeling of the elasto-viscoplastic deformation of rubber-toughened glassy polymers 

Mats Danielsson, David M. Parks and Mary C. Boyce
Journal of the Mechanics and Physics of Solids, In Press, Corrected Proof, Available online 27 November 2006

Xuanhe Zhao's picture

3D FEM modeling of composite

Now we can generate the mesh for the composite model with small balls as inclusion phase.

Subscribe to Comments for "ES 246 project: Planar Composite under Plastic Deformation"

Recent comments

More comments


Subscribe to Syndicate