The Microstructure and Microwave Dielectric Properties of Ceramics in the System CaTiO3-Li0.5Nd0.5TiO3 |
Tristan Lowe, Feridoon Azough1, Robert Freer1 |
Materials Science Centre, University fo Manchester/UMIST Manchester 1Materials Science Centre, University of Manchester/UMIST Manchester |
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ABSTRACT |
Ceramics of xCaTiO$_3$-(1-x)Li$_{0.5}$Nd$_{0.5}$TiO$_3$(xCT-(1-x)LNT) series have been prepared by the mixed oxide route. Powders were calcined at 110$0^{circ}C$ ; cylindrical specimens were fired at temperatures in the range 1300-150$0^{circ}C$. Sintered products were typically 90-95% dense. The microstructures were dominated by angular grains typically 1.3${mu}{textrm}{m}$ to 3.5 ${mu}{textrm}{m}$ in size. Twinning in the microstructures was analysed using Electron Back Scattered Diffraction (EBSD). Microwave dielectric properties of xCT-(1-x)LNT at 2.1 GHz ($varepsilon$$_{r}$, Qxf, and $tau$r) were 170,3800 GHz and 744 ppm/$^{circ}C$ for pure CaTiO$_3$ and 80,2000 GHz and -240 ppm/$^{circ}C$ for LNT. The $tau$r decreases almost linearly from 744 for pure CaTiO$_3$ to -240 for pure LNT.LNT.T. |
Key words:
Perovskite, $CaTiO_3$, Microwave dielectric, Electron Back Scatter Diffraction(EBSD) |
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