Grain Size Effects on Piezoelectric Properties and Domain Structure of BaTiO3 Ceramics Prepared by Two‐Step Sintering

A series of highly dense barium titanate (BaTiO3) ceramics with the average grain size (GS) from 0.29 to 8.61 μm are successfully prepared by two-step sintering, and the GS effect on piezoelectric coefficient (d33) is systematically discussed in this work. It is found that when GS above 1 μm, d33 can be enhanced with decreasing GS, reaching a maximum value of 519 pC/N around 1 μm due to the high activity of domain wall mobility. Subsequently, d33 rapidly drops with a further decrease in GS owing to the reduced domain density. The results suggest that it is possible to prepare high-performance BaTiO3 ceramics by controlling the GS and domain configuration properly, which brings great revitalization to the BaTiO3-based piezoceramics.