Ge-doping in TiO2-Nb2O5-CaCO3 Varistor Ceramics: Structure and Property

Effect of Co3O4 doping on nonlinear coefficient in Zn-Bi-Ti-O varistor ceramics

In the ZnO based varistor, the improvement of nonlinear coefficient (α) and prevention of evaporation of Bi2O3 during heat treatments can be achieved by the addition of MnO2 or Co3O4. In this conjunction, it is proper to see the effect of these additives at different low mol percentage and sintering conditions to nonlinear coefficient improvement of the varistor ceramics. In this paper, the inv...

Metal Oxide ZnO-Based Varistor Ceramics

Hot compaction of nanocrystalline TiO2 (anatase) ceramics. Mechanisms of densification: Grain size and doping effects

The hot compaction of nanocrystalline TiO2 anatase powders is investigated using dilatometry. The constant rate of heating (CRH) method is applied to determine effective activation energies of the processes involved during sintering. Grain size and doping effects are studied, using dopant cations of different radius and charge: Zn, Al, Si, Nb. The results are interpreted by a mechanism includin...

RETRACTED: Effects of N Doping on Structure and Improvement Photocatalytic Properties of Anatase TiO2 Nanoparticles

Homogenized Maxwell’s Equations; a Model for Varistor Ceramics

A model for a semiconducting ceramic material used in devices to protect electrical equipment against overvoltages is presented. The fine structure in the material induces highly oscillating coefficients in the Maxwell equation. Maxwell equations are homogenized to obtain a coupled system. The fine scales in the model yield a local problem coupled with the homogenized Maxwell’s equations. In th...