The anomalous increase in tunability in Ba0.55Sr0.45TiO3‐MgO‐Mg2SiO4 composite ceramics

Abstract

AbstractThe Ba0.55Sr0.45TiO3–Mg2SiO4–MgO composite ceramics were prepared via solid‐stated method and the dielectric tunable properties of composite ceramics were investigated. With the increase in dielectrics content, the tunability of composites ceramics increased abnormally first and then decreased, while the anharmonic coefficient increased monotonously. A simple 3D Finite Element model was developed to simulate the dielectric response and an anomalous increase in tunability when increasing the dielectrics content in composites was obtained. The simulation indicated that adding dielectrics into ferroelectrics causes the redistribution of the electric field. Increasing dielectrics content, the average electric field strength in the enhanced area of ferroelectrics increases, which lead to the increase in the tunability. The abnormal increase in tunability originates from the enhancement of the electric field on a fraction of the ferroelectrics around dielectrics.