Abstract :
The work-hardening behavior of piezoelectric composites is investigated by utilizing the
variational principle and the equivalent inclusion method. When the matrix of a piezoelectric
composite subjected to a uniaxial tension is perfectly plastic and the piezoelectric inhomogeneities
are elastic, the linear work-hardening rate is predicted. In particular, when both the matrix and the
inhomogeneities of the piezoelectric material are transversely isotropic with different electroelastic
moduli, and shapes of the inhomogeneities are elliptical, ribbon-like, rod-shaped and penny-shaped,
the yielding stress and the work-hardening rate are obtained in closed forms. The results show that
the work-hardening rate is proportional to the volume fraction of the inhomogeneities. Moreover,
it is found that the work-hardening rate and the yielding stress are dependent on the shape and the
volume fraction of the inhomogeneities but are independent on the size of the inhomogeneities.
