Ferroelectrics · 1996 · 18 citations · 3 references
Natural SciencesMaterials EngineeringMaterials ScienceCeramic MaterialsCeramicsSolid State PhysicsDielectric CeramicsElectrical Properties Of CeramicsFerroelectric CeramicsFerroelectric MaterialsPiezoelectric CeramicsPiezoelectric MaterialsDielectric ConstantDielectric Constant MeasurementElectrical ResistivityIsomorphic SubstitutionPhase Transition TemperaturePoling BehaviorSubstitutionsTellurium Chemistry
Abstract Aurivillius ferroelectric ceramics, based on the Bi2Sr Nb2O9 compound, have been developed by making isomorphic substitutions in the (Bi2O2)2+ layer. High density ceramics were obtained by the uniaxial hot-pressing sintering technique. The macroscopic characterization was carried out by measuring both the dielectric constant, in the frequency range from 100Hz to 15MHz at temperatures between 20°C and 850°C, and piezoelectric parameters. We found that increasing the amount of cation Bi3+ substitution results in higher transition temperature values. Samples showed a high electrical resistivity that made poling difficult. Anyway, we found an important piezoelectric activity in the samples with tellurium present in their composition, with d33 greater than 11pC/N.
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