The combination of AFE phase structural regulation and breakdown strength optimization through chemical modification leads to a large energy-storage density of Wrec ∼ 5.57 J cm−3 in NN–BMT lead-free bulk ceramics.

A giant electrostrictive effect was observed in (1 À x)NaNbO 3-xBaTiO 3 relaxor ferroelectric ceramics, which exhibit a high electrostrictive coefficient Q 33 of $0.046 m 4 /C 2 twice as large as those of Pb-and Bi-based perovskite relaxor ferroelectric ceramics. The theoretical analysis suggests that Q 33 should be strongly correlated with chemical species of cations in a perovskite structure in which a strong ionic bond is of great benefit compared with a covalent bond. A hysteresis-free large electrostrictive strain of $0.148% up to at least 70 Hz was obtained in the x ¼ 0.25 sample, demonstrating significant advantages over piezoelectric effects in high-precision ceramic actuators.

No abstract

No abstract

No abstract