Ultra-broad working temperature dielectric material system BaFe0.05Nb0.05Ti0.9O3-Bi0.5Na0.5TiO3-BiMg2/3Nb1/3O3

Abstract A novel system of lead-free dielectric temperature stability materials BaFe 0.05 Nb 0.05 Ti 0.9 O 3 -Bi 0.5 Na 0.5 TiO 3 - x BiMg 2/3 Nb 1/3 O 3 are fabricated via a conventional solid state reaction method. The concerted mechanism on the dielectric properties of different proportion of BMN additive in BaFe 0.05 Nb 0.05 Ti 0.9 O 3 -based ceramics is investigated systematically. The phase transition, and dielectric properties have been obtained by X-ray diffraction and dielectric measurements as a function of chemical composition and temperature. Microstructure and crystal structure are investigated, and electrical responses are observed in the combined modulus and impedance plots. With increasing the BMN non-ferroelectric phase, core-shell structure disappeares, temperature-stable dielectric properties over a wide temperature range. The x  = 0.2 ceramic shows the optimal dielectric performance, has TCC values of ± 15% from −55 to 450 °C, with permittivity value at room temperature is 605. The good TCC demonstrates that the BFNT-BNT- x BMN system would have a promising future in application as ultra-broad working temperature and high frequency dielectrics.