Structure and electrical properties of strontium barium niobate ceramics

SBN, x=0.25, 0.35, 0.50, 0.60 and 0.75 series of ceramics prepared by traditional sintering method have been studied systematically. The impact of composition and sintering temperature on structures, microstructures, and electrical properties of SBN ceramics was characterized of X-ray diffraction, scanning electron microscopy, and electrical measurements. It is found that the composition and temperature play an important role on the fabrication of single phase tetragonal TTB SBN ceramics. At x=0.5, TTB SBN ceramics can be obtained at 1200°C. For x<0.5, it consists of a mixture of TTB structure SBN and orthorhombic phase BaNb2O6 even at 1300°C; TTB structure SBN and orthorhombic phase SrNb2O6 for x>0.5. The complete TTB phase is produced at 1350°C. With Sr content increasing, the electrical performances show a regular change, strongly conforming to the reducing of the Curie temperature. SBN with the Sr composition of x=0.60–0.75 is a promising candidate for electro-optics device applications.