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Conventional Solid-state Ceramic Route (conventional + solid-state_ceramic_route)
Selected AbstractsMicrowave Dielectric Properties of SrO,2CeO2,nTiO2 (n=4 and 5) CeramicsINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 2010Ramachandran Satheesh SrO,2CeO2,nTiO2 ceramics with n=4 and 5 have been prepared through conventional solid-state ceramic route. Structural and microstructural characterizations of the sintered ceramics were carried out using X-ray diffraction, laser Raman, and scanning electron microscopic studies. Microwave dielectric properties have been measured using postresonator and resonant cavity techniques. SrO,2CeO2,4TiO2 and SrO,2CeO2,5TiO2 ceramics showed dielectric constants of 71.3 and 71.7, respectively, around 4 GHz together with a relatively high unloaded quality factor. [source] A Novel Temperature-Compensated Microwave Dielectric (1,x)(Mg0.95Ni0.05)TiO3,xCa0.6La0.8/3TiO3 Ceramics SystemINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 5 2009Chun-Hsu Shen The microstructure and microwave dielectric properties of a (1,x)(Mg0.95Ni0.05)TiO3,xCa0.6La0.8/3TiO3 ceramics system have been investigated. The system was prepared using a conventional solid-state ceramic route. In order to produce a temperature-stable material, Ca0.6La0.8/3TiO3 was added for a near-zero temperature coefficient (,f). With partial replacement of Mg2+ by Ni2+, the dielectric properties of the (1,x)(Mg0.95Ni0.05)TiO3,xCa0.6La0.8/3TiO3 ceramics can be promoted. The microwave dielectric properties are strongly correlated with the sintering temperature and the composition. An excellent Q × f value of 118,000 GHz can be obtained for the system with x=0.9 at 1325°C. For practical application, a dielectric constant (,r) of 24.61, a Q × f value of 102,000 GHz, and a temperature coefficient of resonant frequency (,f) of ,3.6 ppm/°C for 0.85(Mg0.95Ni0.05)TiO3,0.15Ca0.6La0.8/3TiO3 at 1325°C are proposed. A parallel-coupled line band-pass filter is designed and simulated using the proposed dielectric to study its performance. [source] Microwave Dielectric Properties of SrRE4Si3O13 (RE=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Tm, Yb, and Y) CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2009Sherin Thomas The apatite type SrRE4Si3O13 (RE=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Tm, Yb, and Y) ceramics have been prepared by the conventional solid-state ceramic route. The phase purity and surface morphology of the sintered ceramics were studied using X-ray diffraction and scanning electron microscopy methods. These materials showed poor sinterability and was improved by the addition of a small weight percentage of zinc borosilicate glass. The microwave dielectric properties of these materials were studied for the first time. SrRE4Si3O13 ceramics have a low relative permittivity (,r) in the range 9,16, a Q-factor (Qu×f) upto 26 000 GHz and a low temperature coefficient of resonant frequency (,f). The SrLa4Si3O13 ceramics possessed a high Qu×f of nearly 26 000 GHz but with a high negative ,f of ,46 ppm/°C. The ,f of SrLa4Si3O13 ceramics was tuned by the addition of suitable amount of TiO2. [source] Preparation, Characterization, and Microwave Properties of RETiNbO6 (RE = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, and Yb) Dielectric CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 7 2001Mailadil T. Sebastian Microwave ceramic dielectric resonators (DRs) based on RETiNbO6 (RE = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, and Yb) have been prepared using the conventional solid-state ceramic route. The DR samples are characterized using XRD and SEM methods. The microwave dielectric properties are measured using resonant methods and a net work analyzer. The ceramics based on Ce, Pr, Nd, and Sm have dielectric constants in the range 32,54 and positive coefficient of thermal variation of resonant frequency (,f). The ceramics based on Gd, Tb, Dy, Y, and Yb have dielectric constants in the range 19,22 and negative ,f. [source] | ||||||||||