Dielectric-temperature stability and breakdown strength of the Nb-doped 0.12BiAlO3-0.88BaTiO3 ceramics with B–Al–Si glass additive

Abstract

[(0.12BiAlO3-0.88BaTiO3)+0.5 wt%Nb2O5]+x wt.% B–Al–Si glass ceramics (x = 0, 1, 2, and 4) were prepared by solid-state method. The effects of B–Al–Si glass additive on microstructural and electrical properties were investigated. After the adding of B–Al–Si glass, quartz appeared as a new impurity phase and the average grain size of the samples decreased (from 540 nm to 330 nm). All the samples satisfy the EIA X8R specification, meanwhile, the breakdown strength (BDS) increased (from 17 kV/mm to 29 kV/mm) with the rising glass content. The ratios of relaxation time of grain boundary to grain (τgb/τg) of the ceramics at 460 °C were calculated according to the complex impedance data. It is found that decreased value of τgb/τg suggests a weakened interfacial polarization effect after B–Al–Si glass addition, which is beneficial to the BDS performance of ceramics.