Korean Journal of Materials Research, Vol.17, No.8, 442-446, August, 2007
Low Temperature Sintering and Microwave Dielectric Properties of 0.85CaWO4-0.15LnNbO4 (Ln = La, Sm) Ceramics
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Microwave dielectric properties of (Ln = La, Sm) ceramics were investigated as a function of the sintering temperature and content from 0.8 wt.% to 1.5 wt.%. A single phase with tetragonal scheelite structure was obtained at a given composition ranges. For the specimens with , the sintering temperature could be effectively reduced from to due to the enhancement of sinterability. Dielectric constant (K) of the specimens with and was increased with the increase of sintering temperature and/or content. However, K of the specimens with was higher than that of due to the larger dielectric polarizability of () than that of (). With an increase of content, Qf value of the specimens with was decreased, while that of the specimens with was increased. Temperature coefficient of resonant frequency (TCF) was increased with the increase of content.
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