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Ba0.65Sr0.35TiO3-x Bi3NbZrO9(BST-x Bi3NbZrO9, x = 0.5, 1, 3, 5, 7 wt.%) ceramics sintered at low temperature were prepared by traditional solid state reaction method. Influence of Bi3NbZrO9doping amount on the dielectric properties and microstructure of (Ba, Sr)TiO3(barium strontium titanate, BST) capacitor ceramics by means of X-ray diffraction(XRD), Scanning electron microscopy (SEM) and traditional solid state sintering method. The results showed that the impurity materials phase were appeared when Bi3NbZrO9doping amount increased. When Bi3NbZrO9doping amount increased, dielectric constant(ϵr)increased firstly and then decreased and then increased, dielectric loss(tanδ) decreased firstly and then increased, the capacitance temperature changing rate(ΔC/C) decreased. When Bi3NbZrO9doped amount was 1 wt.% and the sintered temperature was 1280°C, the BST ceramics possessed good comprehensive property with ϵrof 2325, tanδ of 0.0048, Ebof 7.8 kV/mm(AC), ΔC/C of −12.9∼14.3% in the temperature range of −30°C∼85°C and the capacitance temperature characteristic was consistent with Y5R. [ABSTRACT FROM PUBLISHER]

(1-x) Ba0.65Sr0.35TiO3-xCaCu3Ti4O12(BST-CCTO) ceramics was prepared by traditional solid-state reaction method, the effect of CaCu3Ti4O12(CCTO) doped on microstructure and phase composition and dielectric properties of BST ceramics were investigated by X-ray diffraction(XRD), scanning electron microscope(SEM) and other analytical methods. The results show that the microstructure and the dielectric properties and the optimum sintered temperature of BST ceramic materials would be greatly affected by the CCTO doped amount. Appropriate doping amount can be fully incorporated into the perovskite lattice of BST and had the excellent performance. While excessive CCTO doping could lead to the appearance of second phase, and the second phase was coexisted with BST in the ceramics. BST ceramics had the optimum properties, ϵrof 1992, tan δ of 0.006, Ebof 5.5 kVmm−1(Alternating Current, AC) and the value of ΔC/C ranges was 13.6% and −14.1% in −55°C∼+125°C temperature range and its capacitance temperature property was suited for X7R, the curie temperature was 15°C and the optimum sintered temperature was 1260°C when CCTO doped amount was 1 wt.%. [ABSTRACT FROM AUTHOR]

(1 − x) BaSrTiO-xMgSnO (BST-xMgSnO, x = 0.5, 1, 3, 5, 7 wt%)ceramics sintered at low temperature were prepared by traditional solid-state reaction method and the effect of MgSnO doped on the microstructure and dielectric property of BST ceramics sintered at low temperature were investigated by X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy. The results showed that the main phase of BST ceramics doped with MgSnO had perovskite structure and a small amount of MgTiO and SrTiO impurity phase. MgSnO doping in BST ceramics sintered at low temperature could shift, pressure and broaden Curie peak remarkably. Dielectric constant (ε) decreased firstly and then increased, dielectric loss (tanδ) decreased firstly and then increased and then decreased, withstand voltage (E) increased firstly and then decreased and then increased when MgSnO doped amount increased. When MgSnO doping amount was 1 wt%, BST ceramics sintered at low temperature had better property with ε of 2,603, tanδ of 0.006, E of 6.3 kV/mm (AC), the sintered temperature was 1,050 °C, the value of △C/C range was 12.5 to −14.8 % in −30 to 85 °C temperature range and the capacitance temperature property was suited for Y5R. [ABSTRACT FROM AUTHOR]

Terbium aluminum garnet (TAG) transparent ceramics were fabricated by solid-state reactive sintering in vacuum combined with hot isostatic pressing (HIP) post-treatment using tetraethoxysilane (TEOS) as sintering aid. The influences of TEOS amount on the densification, microstructure and optical properties of TAG ceramics were investigated. The in-line transmittance of the TAG ceramic with 0.2 wt% TEOS additive, which was fabricated by pre-sintering at 1700 °C for 20 h and HIP post-treating at 1700 °C for 3 h, can reach about 66% in the visible and near-infrared regions. With appropriate amount of sintering aid, the transmittance of TAG ceramics in the visible wavelength range can be improved significantly by prolonging the holding time. • TAG transparent ceramics were prepared by solid-state reactive sintering and HIP post-treatment. • Influences of TEOS amount on microstructure and optical quality of TAG ceramics were investigated. • Prolonging the pre-sintering time can improve the in-line transmittance of TAG transparent ceramics. [ABSTRACT FROM AUTHOR]