Synthesis and characterization of Ba_(6-3x)Sm_(8+2x)Ti_(18)O_(54) microwave dielectric ceramics

摘要

Dielectric ceramics in the BaO-Sm_2O_3-TiO_2 ternary system have been synthesized and characterized. Solid solutions with the formula Ba_(6-3x)Sm_(8+2x)Ti_(18)O_(54) with x = 0.0, 0.2-0.7 have been synthesized, which are in the vicinity of BaO-Sm_2O_3-4TiO_2 (consistent with x = 0.5) ternary system. X-ray powder diffraction (XRD) analysis of synthesized specimens has been done from which lattice parameters as a function of composition (x) were determined. Crystal symmetry was found out to be orthorhombic with space group of Pbam. Scanning electron microscopy (SEM) was done to observe the microstructural details of the sintered compacts. The synthesized compacts of Ba_(6-3x)Sm_(8+2x)Ti_(18)O_(54) solid solutions exhibited good dielectric properties with dielectric constant (V) in the range of 65-73 and tangent loss (tan S) in the range of 2 x 10~(-2) to 9 x 10~(-2) , in the frequency range of 0.3-3.0 GHz, for their possible use in microwave frequency applications.