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Sintering temperature effects on the energy‐storage properties in barium strontium titanate glass–ceramics have been studied by polarization hysteresis measurements. In phase development and microstructure evolution tests, it was found that with the increase of sintering temperature, the crystallinity degree of primary ferroelectric phase increases. Dielectric measurements revealed a rapid increase over the sintering temperature range from 800° to 830°C. This effect is believed to be due to the emergence of ferroelectric phase. The variation in dielectric constant with sintering temperature is attributed to the change in crystallization mechanism between surface and interior of glass–ceramics. Moreover, the charged and discharged energy densities for the glass–ceramic samples sintered at different temperatures were measured by the use of the Sawyer–Tower circuit under unipolar field. It has been shown that the low released energy density in glass–ceramics is mainly caused by interfacial polarization.

A series of BaTiO 3 (BT)-based ferroelectric glass-ceramics have been prepared via controlled crystallization by varying the Ba/Ti ratio in an aluminum silicate glass composition, and the subsequent microstructure, phase evolution, and dielectric properties have been investigated. X-ray diffraction indicated that an increasing Ba/Ti ratio promoted the crystallization of BaTiO 3 and BaAl 2 Si 2 O 8 from the glass matrix, and the cracking of glass-ceramics appears to be correlated to mismatch in the thermal expansion coefficient among BaTiO 3 , BaAl 2 Si 2 O 8 , and the glass matrix. In addition, it was found that increasing the Ba/Ti ratio facilitated the formation of a dendrite structure with obvious porosity. The change in the Ba/Ti ratio in the glass notably modified the dielectric properties: a high Ba/Ti ratio in the glass resulted in an increased dielectric constant and decreased breakdown strength.