The grain-size effects of the direct piezoelectric coefficient (d₃₃) and the converse piezoelectric coefficient (d₃₃*) of BaTiO₃ ceramics with different Ba/Ti ratios were systematically explored. It was found that both d₃₃ and d₃₃* exhibited strong grain size (g) dependences for BaTiO₃ ceramics with various Ba/Ti ratios. Although d₃₃ showed similar grain-size dependence for all the Ba/Ti ratios except a subtle shift of the critical grain size from 1 μm to 3 μm, two entirely different grain-size dependence of d₃₃* were observed. By carefully examining the microstructure and ferroelectric properties of the ceramics, the variations of domain configurations and maximum polarization of BaTiO₃ ceramics with different Ba/Ti ratios were considered to be responsible for the different grain-size dependence of d₃₃ and d₃₃*, respectively.

系统地研究了不同Ba / Ti比的BaTiO ₃陶瓷的直接压电系数（d ₃₃）和反压电系数（d ₃₃ *）的粒度效应。已经发现，对于具有各种Ba / Ti比的BaTiO ₃陶瓷，d ₃₃和d ₃₃ *均表现出很强的晶粒尺寸（g）依赖性。尽管d ₃₃对于所有Ba / Ti比都显示出相似的晶粒尺寸依赖性，但临界晶粒尺寸从1μm微小变化到3μm，但d _33的两种完全不同的晶粒尺寸依赖性*被观察到。通过仔细检查陶瓷的微观结构和铁电性能，认为不同Ba / Ti比的BaTiO ₃陶瓷的畴构型变化和最大极化是造成d ₃₃和d ₃₃ *不同晶粒尺寸依赖性的原因，分别。