Processing and polarization behavior of Sr-containing lead zirconate titanate

Abstract

Sr-containing PZT compositions were selected for identifying the ferroelectric (FE)-antiferro-electric (AFE) phase boundary within the zirconium rich region of the PbZrO₃-PbTiO₃-SrTiO₃-SrZrO₃ phase diagram and for inducing the AFE-FE phase transition upon application of an applied electric field. Processing methods, based on the powder processing and sintering, were developed for fabricating dense (98.5% of theoretical density) Sr-containing PZT samples suitable for the polarization measurements. PZT specimens, with a uniform microstructure and an average grain size of 3 μm were obtained. Polarization measurements were used to locate the FE-AFE phase boundary. Subsequently, compositions near the FE-AFE phase boundary were studied for the electric field induced AFE-FE phase transition. Field-induced AFE-FE phase switching was observed in compositions close to the AFE-FE boundary. Residual polarization upon AFE-FE transformation suggested a coexistence of both ferroelectric and antiferroelectric phases.

Key Words:

• Lead zirconium titanate
• phase diagram
• field-induced transition
• polarization behavior
• dielectric ceramics
• “smart” ceramics