Electrical properties of ferroelectric Sr0.5Ba0.5Nb2O6 ceramic materials synthesized by different techniques

Strontium Barium Niobate (Sr
_x
Ba
_1-x
Nb
₂
O
₆
, abbreviated as SBN) is a promising lead free ferroelectric-ceramic material. It belongs to the family of tetragonal tungsten bronze structured ferroelectrics. Unlike other family of ferroelectric perovskites such as, PMN and BT where, only one composition gives the ferroelectric phase, SBN exhibits ferroelectricity in the composition range 0.25≤x≤0.75. This in turn, results in a material with different Curie temperatures, microstructures, dielectric and ferroelectric properties. However, the unusual sintering behavior of SBN, leading to abnormal grain growth, duplex microstructure and low density, has plagued commercial exploitation of SBN. We have employed several synthesis methods for example solid-state (conventional as well as microwave sintered), partial coprecipitation and coprecipitation to synthesize SBN of one specific composition (Sr
_0.5
Ba
_0.5
Nb
₂
O
₆
). The different methods resulted in materials having varying microstructure and dielectric properties. For practical application of a ferroelectric material, the ferroelectric properties stand above all other properties due to its wide possible applications in memory and actuators. The main thrust of this paper is on how the ferroelectric properties e.g. Hysteresis, I-V characteristics, Leakage test and Electrical fatigue behavior vary with different synthesis approaches and the consequent microstructure.