From the results, the phase transition in the inclusion and layer
composites can be explained as follows. The two-layered composite
with a ratio of 0.1e0.4 exhibited small increases in polarization and
strain compared to the pure relaxor specimen. Based on a serial
capacitor model which is related to the dielectric permittivity of the
two phases, the layered composites show a small improvement in
relaxor-to-ferroelectric phase transition. On the other hand, the
polarization and strain behavior showed that the inclusion composite
is considerably more effective than the layer composite in
relaxor-to-ferroelectric phase transition. It could be expected that
the ferroelectric phase can easily grow from the interfaces in the
inclusion composite. It can be concluded that the existence of
ferroelectric inclusions may help a transition from nano-sized polar
regions to a large ferroelectric domain in the relaxor matrix.