Abstract
• High electrostrictive coefficient was achieved in KNN-based ferroelectric ceramics. • Ultra-high electrostrictive strain (>0.3%) with ultra-low hysteresis was obtained. • This study broadens the research direction of KNN-based materials. The longitudinal electrostrictive coefficient Q 33 for perovskite-structured ferroelectric ceramics is usually between 0.01−0.04 m 4 /C 2 . However, an ultra-low Q 33 of only 0.0047 m 4 /C 2 was identified in the 0.9K 0.5 Na 0.5 NbO 3 -0.1SrTiO 3 (KNN-ST) composition. Despite the fact that superior piezoelectricity has been observed in KNN-based ceramics, this value is obviously much smaller than the normal value, according to the general cognition and the thermodynamic relationship between piezoelectric coefficient d 33 and Q 33 . Therefore, we synthesized (1− x )(K 0.45 Na 0.49 Li 0.06 )NbO 3 - x SrTiO 3 (KNLN-ST) and studied phase structure, dielectric and ferroelectric properties systematically. Our findings show that the Q 33 in the KNLN-ST system (0.012−0.027 m 4 /C 2 ) is within the reasonable range for perovskite-structured ferroelectric ceramics. Furthermore, an ultra-high electrostrictive strain (>0.3%) with ultra-low hysteresis was achieved in the 0.8KNLN-0.2ST sample. This research not only clarifies the electrostrictive effect in KNN-based systems, but it also broadens the potential application field of KNN-based ceramics to electrostrictive actuators.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call