Search

(Zr,Sn)TiO4 nano-powders for microwave ceramics were prepared by a hydrothermal synthesis route. Raw materials of ZrOCl2, ZrO(NO3)2, SnCl2, TiO2 and de-ionized water were used, and the mixture was stirred in an auto-clave at 160–230 °C. Resulting powders with particle size of 10–120 nm were washed, dried and pressed into pellets, which were then sintered at 1200–1300 °C. The sintering process was analyzed by TGA and DTA. Microstructures of the powder and sintered ceramics were observed by TEM and SEM. Crystalline phases of the ceramics were identified by XRD. Dielectric properties of the samples were: dielectric constant 30–45 and Q*f=10,000–25,000 GHz at 10 GHz. [Copyright &y& Elsevier]

Ba2Ti9O20 nano-powders for microwave ceramics were prepared by a hydrothermal synthesis route. Raw materials of Ba(OH)2·8H2O (AR), TiO2 (CP)and de-ionized water were used, and the mixture was stirred in an auto-clave at 130–200 °C. Resulted powders with particle size of 10–120 nm were washed, dried and pressed into pellets, which were then sintered at 1200–1300 °C. Sintering process was analyzed by TGA and DTA. Microstructures of the powder and sintered ceramics were observed by TEM and SEM. Crystalline phases of the ceramics were identified by X-ray diffraction. Dielectric properties of the samples were also measured, displaying dielectric constant of 25–55 and Qf=1000–15000 GHz at 10 GHz. [Copyright &y& Elsevier]

Sr(Bi1−xNdx)8Ti7O27 ceramics for wireless technologies were prepared by a solid-state reaction route. Raw materials of SrCO3, Bi2O3, Nd2O3 and TiO2 were used. The mixture was ball-milled, dried, and hydro-pressed into pellets or formed into green body by gel-casting, which were then sintered at 1180–1300 °C. Sintering process was analyzed by TGA and DSC. Microstructure of ceramic body was observed by SEM. Crystalline phases of the ceramics were identified by X-ray diffraction. Dielectric properties of the samples were also measured, showing dielectric constant ϵ=80–110 and Qf=120–2100 GHz at 10 GHz. [Copyright &y& Elsevier]