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According to recent domestic and international niobate ceramic materials research progress and the main problems, the use of differential thermal analyzer, X-ray diffraction, scanning electron microscopy, dielectric properties tester System oxide to replace the glass phase the microscopic structure of the additives and preparation of strontium barium niobate ceramics, sintering properties, phase composition and dielectric properties were investigated. The main conclusions are as follows: the system of the of titania doping and sintering process of the phase transition, the dielectric properties of strontium barium niobate ceramics: When the amount of titanium dioxide doped y ≤ 0.1, the formation of a small amount of barium strontium titanate (SBT ), solution in the strontium barium niobate (SBN); When the doping amount of y ≥ 0.2, showing a two-phase coexistence of SBN and SBT; when the sintering temperature below 1300 ° C, SBTN density of the ceramic sintering temperature rise increases, when the temperature continues to rise, y = 0 and 0.1 ceramic density of the sample decreased, y = 0.2 and 0.3 ceramic density of the sample rose slightly; with titania doping amount of increase, The dielectric constant of the ceramic samples first increases and then decreases. When y = 0.1, the dielectric constant of the sample reached the maximum of 11798. Rare earth ion doped the SBTN sample La 3 ion Nb5 ions replace the tungsten bronze structure to form the structure of space, resulting in the decrease of the lattice spacing, Ce 4 ions in tungsten placeholder in the bronze structure is more complex; 3 doped rare earth ions La Ce 4 of the SBTN ceramic samples sintered density, dielectric constant and dielectric loss have declined, the dielectric heat stability are rising. System to study the impact of the phase transition of strontium barium niobate ceramics doped alkaline earth element oxides, dielectric properties: alkaline earth metal elements Ca, Mg-doped SBN ceramics, Ca 2 ion substitution tungsten bronze structure of Sr in the A position 2 , the Ba 2 ion, Mg 2 ion filled tungsten bronze structure in the C position; doping of Ca Mg ceramic samples after sintered at 1300 ℃ grains have different degrees of increase, but the crystal structure of tetragonal tungsten bronze structure remains; Ca ion doping SBN ceramic, respectively at 150 ° C and 330 ℃ near SBN50 and (Sr , Ba, Ca,) Nb2O6 Curie temperature peak, as the doping amount increases, the Curie temperature of the (Sr, Ba, Ca), Nb2O6 the peak gradually disappear; when Mg ion doped the SBN ceramic, at 150 ℃ and 310 ℃ near the peaks, and as the doping amount increases, doublet merged into a single peak, to the direction of the cryogenic movement. Doped strontium barium niobate low melting point material, the use of the melting point of the difference of the two substances, liquid phase sintering process, low-melting substances coated strontium barium niobate grains to form a shell - core structure for the first time, thereby improving the niobium ceramic barium strontium performance. Doping 2wt? S-glass strontium barium niobate ceramic sintering at 1100 ℃ low temperature and no obvious impurity generated significantly reduce the the traditional craft preparation SBN ceramic sintering temperature; With the increase in the amount of CBS doped, SBN ceramic the Curie temperature point moves to the low temperature direction, the permittivity in the Curie temperature is first increased and then decreased, the dielectric loss decreased gradually; to appear obvious CaNbO3 phase when CBS doping amount is higher than 5 wt%, the ceramic sample, and The dielectric properties have a greater impact. High energy ball milling process preparation of strontium barium niobate powders for the first time. The milled powder is not calcined, direct compression molding, kept at 1250 to 1350 ° C for 1.5 to 12H Preparation SBN50 ceramic material, and this X-ray diffraction analysis, scanning electron microscopy, and the dielectric properties. The results show that: the powder after milling 30h 1100 ℃ the heat treatment the synthesis SBN50 pure phase; With the sintering temperature and holding time,, SBN50 ceramic dielectric constant first increases and then decreases, the grain size was a regular changes. 1300 ℃ for 3 h obtained ceramic highest sample permittivity (εmax = 1447), the Curie temperature (Tc) of 130 ° C.
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