Sintering characteristics and microwave dielectric properties of new high-Q Mg2LaNbO6 ceramics

New microwave dielectric ceramics of Mg2LaNbO6, which had high quality factors (Q x f) and near-zero frequency temperature coefficient (tau(f)), were synthesized via conventional solid-state reaction. The sintering characteristic, crystal structure and microwave dielectric properties of Mg2LaNbO6 ceramics were characterized and investigated. As a result, Mg2LaNbO6 ceramics had a complex phase composition: LaNbO4 and MgO as the main and the second phase respectively, with an unknown phase (which related to the MgO) being detected. Well-developed micro-structures of Mg2LaNbO6 ceramics were obtained in the designed sintering temperature zone, with the grain size and its distribution also being investigated. Moreover, the permittivity (epsilon(r)), which was related to the density, remained almost unchanged. The Q x f values increased first and then decreased, which was governed by the grain size and its distribution. Additionally, the tau(f) values of Mg2LaNbO6 ceramics was relatively stable and near to zero.