Effects of Mg(OH)₂ on phase formation and microwave dielectric properties of Mg₆Ti₅O₁₆ ceramics

Abstract

Mg₆Ti₅O₁₆ ceramics have been prepared by the conventional solid-state route using Mg(OH)₂ as the magnesium source and their sinterability, phase composition and microwave dielectric properties were studied. X-ray diffraction analysis indicated that all samples presented mixture phases of MgTiO₃ and Mg₂TiO₄. As the sintering temperature rising, the density, ε _r and Q׃ values first increased and then decreased, whereas the τ_f values did not change remarkably. Typically, nominal ceramics Mg₆Ti₅O₁₆ sintered at 1340 °C owned good microwave dielectric properties: ε _r=16.7, Q × f = 143 481 GHz (at 8.55 GHz), and τ _f= −51.5 ppm/°C. The correlation between dielectric properties and microstructure is also discussed.

KEYWORDS:

• Dielectric properties
• ceramics
• microstructure

Additional information

Funding

This work is supported by the National Natural Science Foundation of China (Grant No 51402235), China's Post-doctoral Science Fund (Grant No. 2015M582696), Shaanxi Province Post-doctoral Science Foundation. Shaanxi Province Department Education (Grant No. 18JK0711) and Graduate student innovation fund of Xi'an Post and Telecommunications University (Grant No. CXJJ2017053).