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Microwave Dielectric Properties of (1-x)CaTiO₃-x(Na_0.5Nd_0.5)TiO₃ Ceramics

A.E. Reda, D.M. Ibrahim, D.A. Abdel Aziz

Ceramic Department, National Research Centre, 12622, Dokki, Cairo, Egypt.

received December 8, 2015, received in revised form February 20, 2016, accepted March 8, 2016

Vol. 7, No. 3, Pages 243-248   DOI: 10.4416/JCST2015-00083

Abstract

The crystal structures, phase compositions and the microwave dielectric properties of (1-x)Ca²⁺TiO₃ - x(Na¹⁺_0.5 Nd³⁺_0.5)TiO₃ ceramics prepared by the conventional solid state route have been investigated. The formation of solid solution is confirmed in XRD patterns. A specimen using 0.92Ca²⁺TiO₃-0.08(Na¹⁺_0.5Nd³⁺_0.5)TiO₃ (x = 0.08) sintered at 1250 °C/2 h possesses an excellent combination of microwave dielectric properties, (ε_r) = 31.8, a maximum (Qxf) value of 2·10⁴ at 5 GHz. This may be related to the increase in density as well as the grain morphology, which led to a reduction in the dielectric loss to a value of 0.25·10^-3. It is proposed as a suitable candidate material for small-sized GPS patch antennas.

Keywords

Microwave, dielectric properties, calcium titanate, sodium neodymium titanate

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