naa a22 4500 510803520 CHVBK 20180411083406.0 cr unu---uuuuu 180411e20130301xx s 000 0 eng 10.1007/s11664-012-2387-9 doi (NATIONALLICENCE)springer-10.1007/s11664-012-2387-9 Phase, Microstructure, and Microwave Dielectric Properties of NaCa4− x Sr x Nb5O17 ( x =0 to 4) Ceramics [Elektronische Daten] [Y. Iqbal, R. Muhammad] A series of A5B5O17-type NaCa4−x Sr x Nb5O17 (x=0 to 4) compounds were processed through a solid-state mixed-oxide route. All the compositions formed dense single-phase ceramics within the detection limit of an in-house x-ray diffraction facility when sintered at 1300°C. The substitution of Sr for Ca changed the crystal symmetry from monoclinic (x=0) to orthorhombic (x=1 to 4) along with a slight increase in molar cell volume due to the relatively larger ionic radius of Sr. The relative permittivity (ε r) and temperature coefficient of resonance frequency (TCF) increased from 46 to 84 and from −117ppm/°C to +377ppm/°C, respectively, while the quality factor (Q×f) decreased from 11,063GHz to 559GHz with an increase in x from 0 to 4. Optimum properties were achieved for NaCa3SrNb5O17, which exhibited ε r=57, Q×f=4628GHz, and TCF=−41 ppm/°C. Compounds in the NaCa4−x Sr x Nb5O17 series exhibited high ε r and Q×f with adjustable TCF; however, further work is required for simultaneous optimization of all three properties. TMS, 2013 Ceramics nationallicence dielectric properties nationallicence microstructure nationallicence Iqbal Y. Materials Research Laboratory, Institute of Physics & Electronics, University of Peshawar, 25120, Peshawar, Pakistan aut Muhammad R. Materials Research Laboratory, Institute of Physics & Electronics, University of Peshawar, 25120, Peshawar, Pakistan aut Journal of Electronic Materials Springer US; http://www.springer-ny.com 42/3(2013-03-01), 452-457 0361-5235 42:3<452 2013 42 11664 https://doi.org/10.1007/s11664-012-2387-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11664-012-2387-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Iqbal Y. Materials Research Laboratory, Institute of Physics & Electronics, University of Peshawar, 25120, Peshawar, Pakistan aut NATIONALLICENCE 700 1- Muhammad R. Materials Research Laboratory, Institute of Physics & Electronics, University of Peshawar, 25120, Peshawar, Pakistan aut NATIONALLICENCE 773 0- Journal of Electronic Materials Springer US; http://www.springer-ny.com 42/3(2013-03-01), 452-457 0361-5235 42:3<452 2013 42 11664 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer