Na0.5Bi0.5TiO3-0.06BaTiO3 relaxor ferroelectrics (RFEs) ceramic samples were investigated by means of dielectric and acoustic emission methods in the temperature range of 70-350C and in dependence on frequency. Dielectric curve exhibits two anomalies: strongly dispersive the local maximum, within 130-180C and slightly dispersive the smeared high-temperature maximum within 300-310C. Acoustic emission exhibits the five groups of bursts: near 123C, 150-180C, near 225C, 300-310C and 327C. The first and third groups of acoustic emission bursts correspond to phase transitions of R3c-P4bm phases coexisting in this temperature, range, while the fourth and fifth groups of acoustic emission bursts correspond to P4bm-P4/mbm-Pm3 m phase transitions. The second group of acoustic emission bursts corresponds to strongly dispersive local maximum at which no phase transition has been proved in Na0.5Bi0.5TiO3-0.06BaTiO3. The existence and the location of the intermediate temperature, T∗, in Na0.5Bi0.5TiO3-0.06BaTiO3 compound are discussed.
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- Burns temperature
- Lead-free relaxor ferroelectrics
- acoustic emission
- intermediate temperature
- phase transitions