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 8.61m are successfully prepared by two-step sintering, and the GS effect on piezoelectric coefficient (d(33)) is systematically discussed in this work. It is found that when GS above 1m, d(33) can be enhanced with decreasing GS, reaching a maximum value of 519pC/N around 1m due to the high activity of domain wall mobility. Subsequently, d(33) 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.