Campus Units

Materials Science and Engineering

Document Type


Publication Version

Accepted Manuscript

Publication Date


Journal or Book Title

Journal of the European Ceramic Society




Lead-free (K0.5Na0.5)NbO3-based (KNN) piezoceramics featuring a polymorphic phase boundary (PPB) between the orthorhombic and tetragonal phases at room temperature are reported to possess high piezoelectric properties but with inferior cycling stability, while the ceramics with a single tetragonal phase show improved cycling stability but with lower piezoelectric coefficients. In this work, electric biasing in-situ transmission electron microscopy (TEM) study is conducted on two KNN-based compositions, which are respectively at and off PPB. Our observations reveal the distinctive domain responses in these two ceramics under cyclic fields. The higher domain wall density in the poled KNN at PPB contributes to the high piezoelectric properties. Upon cycling, however, a new microstructure feature, “domain intersection”, is directly observed in this PPB composition. In comparison, the off-PPB KNN ceramic develops large domains during poling, which experience much less extent of disruption during cycling. Our comparative study provides the basis for understanding the relation between phase composition and piezoelectric performance.


This is a manuscript of an article published as Fan, Zhongming, Shujun Zhang, and Xiaoli Tan. "Phase-composition dependent domain responses in (K0. 5Na0. 5) NbO3-based piezoceramics." Journal of the European Ceramic Society (2019). DOI: 10.1016/j.jeurceramsoc.2019.11.046. Posted with permission.

Copyright Owner

Elsevier Ltd.



File Format


Available for download on Wednesday, November 17, 2021

Published Version