An increase in grain size increases the dielectric constant, piezoelectric coefficient and hydrostatic figures of merit, which can be explained by the Okazaki space-charge theory.

• 晶粒尺寸增加；多孔PZT陶瓷的介电常数、压电系数和优值增加；并可用Okazaki空间电荷理论解释晶粒尺寸对试样介电和压电性能的影响.