Domain Structure in Excess-WO3 Lead Complex Perovskite

Ferroelectric domain structures in the polycrystalline ternary system Pb(Mg1/3Nb2/3)O3–PbTiO3–Pb(Mg1/2W1/2)O3 were investigated with regard to excess-WO3 addition. Core–shell domain structures were observed in the 2 wt% excess-WO3 specimens. Above 3 wt% excess-WO3 addition, the ferroelectric fringe pattern disappeared at the center of the grain, and ringlike domain structures were observed. This tendency became distinct in 5 wt% excess-WO3 addition, and clear, ringlike domain structures were observed. The structures that consisted of fringe shell parts and non-fringe core parts were reversals of normal core–shell structures.