Microstructure and Dielectric Properties of Barium Strontium Magnesium Niobate

Dielectric properties and their related microstructural characteristics in solid solutions of (1 – x )Ba(Mg 1/3 Nb 2/3 )O 3 – x Sr(Mg 1/3 Nb 2/3 )O 3 (BMN–SMN, or BSMN) were investigated by measuring the relative permittivity (ɛ r ), Q values, and temperature coefficient of resonator frequency (τ f ), and by observing microstructure using transmission electron microscopy. When the tolerance factor ( t ) was >0.99 in BSMN with composition 0 < x < 0.5, where the tilting of oxygen octahedra was not involved, the microstructure included only 1:2 ordered phase. In the region where 0.99 > t > 0.97 with 0.7 < x < 1.0, the phase due to the antiphase tilting of oxygen octahedral, the disordered phase, and the 1:2 ordered phase were also present. In a few of the grains, core–shell‐type structures, whose main components were dislocations and stacking faults, were found in the solid solution of BSMN.