LAUSR

Abstract Ba0.5Sr0.5TiO3−Mg2TiO4−MgO composite ceramics were prepared by spark plasma sintering (SPS) technique and their phase composition, microstructures and dielectric tunable properties were studied. With increasing Mg2TiO4−MgO content, the dielectric peaks of Ba0.5Sr0.5TiO3−Mg2TiO4−MgO composite ceramics were broadened and suppressed. The tunability of Ba0.5Sr0.5TiO3−Mg2TiO4−MgO composite ceramics increased first and then decreased with the increase of Mg2TiO4−MgO content. For Mg2TiO4−MgO content ≤50 wt%, Ba0.5Sr0.5TiO3−Mg2TiO4−MgO composite ceramics showed higher tunability and lower permittivity than pure Ba0.5Sr0.5TiO3, which can be attributed to the suppression of the doping effect by SPS. The contradiction between reduced permittivity and enhanced tunability in ferroelectric-dielectric composites was resolved.