LAUSR

Abstract(1 − x) NiZrNb2O8 − x ZnTa2O6 microwave dielectric ceramics were prepared via the conventional solid-state reaction route. Structural and lattice parameters of the (1 − x) NiZrNb2O8 − x ZnTa2O6 ceramics were analyzed through X-ray diffraction, Raman spectra, and scanning electron microscopy. The results showed that there were serious ionic diffusion and solid solution reaction in the composite ceramics. The substitution of Ni2+, Zr4+, and Zn2+ at A-sites and the substitution of Nb5+ and Ta5+ at B-sites led to the change of the lattice parameters. There was a gradual transformation in crystal structure from monoclinic phase into Tri-αPbO2 phase with the increasing ZnTa2O6 content. With the increase of x value from 0 to 1, the εr value increased from 23.76 to 35.71 and the Q × ƒ value increased from 32107 to 46709 GHz. The temperature frequency resonance coefficient near zero could be obtained at x = 0.8. The 0.2NiZrNb2O8 − 0.8ZnTa2O6 ceramics were obtained at 1275 °C with excellent microwave dielectric properties: εr ~ 33.69, Q × ƒ ~ 37,529 GHz and τƒ ~ + 2.56 ppm/°C.