YingChun Zhang

Microwave dielectric properties of (Zn1-xMgx)Nb2O6 ceramics

Abstract Dielectric ceramics comprised of (Zn 1− x Mg x )Nb 2 O 6 ( x =0–1) with promising microwave properties were prepared by solid ceramic route. (Zn 1− x Mg x )Nb 2 O 6 solid solutions exhibited columbite crystal structure for all compositions. The dielectric properties in this system exhibited a significant dependence on the sintering condition and composition of ceramics. The dielectric constant of (Zn 1− x Mg x )Nb 2 O 6 ceramics increased with increasing relative densities for each x value. On the other hand, the dielectric constant of (Zn 1− x Mg x )Nb 2 O 6 ceramics decreased from 23.66 to 19.7 as x value ranged from 0 to 1.0. The quality factors ( Q × f ) of (Zn 1− x Mg x )Nb 2 O 6 ceramics increased with increasing sintering temperature, after reached the maximum values, then decreased. The highest Q × f values of sintered ceramics changed nonlinearly and ranged from 81,220 to 33,112 GHz. The τ f showed a relative low value compared with those of ZnNb 2 O 6 and MgNb 2 O 6 and ranged from −29.46 to −70.56 ppm/°C. The τ f was improved at x =0.5 and was −29.46 ppm/°C.