Low temperature sintering and microwave dielectric properties of MnZrNb2O8 ceramics with H3BO3 addition

The effects of H3BO3 additions on sintering characteristic, phase composition, microstructure and microwave dielectric properties of MnZrNb2O8 ceramics were investigated. The MnZrNb2O8 ceramics were prepared by the solid-state method. The phase composition, microstructure and elemental composition of the ceramics were studied using X-Ray Diffraction, Scanning Electron Microscopy and Energy Dispersive Analysis. Only a single-phase MnZrNb2O8 was formed in MnZrNb2O8 ceramics with H3BO3 addition. A small amount of H3BO3 successfully reduced the sintering temperature of MnZrNb2O8 ceramics from 1250 to 1200°C without much degradation of the microwave dielectric properties. In addition, the τf values were shifted to positive direction with the increase of H3BO3 contents. Typically, the MnZrNb2O8 ceramic with 1 wt% H3BO3 sintered at 1250°C for 4 h exhibited excellent microwave dielectric properties with Εr = 25.80, Q·f = 28,419 GHz and τf = -8.4 ppm/°C. © 2016 Elsevier B.V. All rights reserved.