K0.5 Na0.5 Nb O3 - (KNN) based lead free materials have been found to exhibit good piezoelectric properties (d33 ∼250 pCN) due to the orthorhombic-tetragonal polymorphic phase transition (PPT) temperature compositionally shifted downward to near room temperature. However, associated with the PPT are issues of temperature and domain instability, making them impractical for applications. In this work, CaTi O3 (CT) was used to effectively shift the PPT downward in effort to mitigate these issues. As expected, CT modified KNN based materials exhibited nearly temperature independent properties (-50∼200 °C) and fatigue-free behavior, together with its relatively high d33 value of ∼200 pCN, make the CT modified KNN based materials excellent candidates for lead free actuators and transducers.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)