Major effects on microstructure and electrical properties of ZnO-based linear resistance ceramics with MgO changes

The ZnO-based linear resistance ceramics were fabricated from ZnO–Al2O3–MgO–TiO2 at 1,340 °C. The effect of the different doping amounts of MgO on the microstructure and electrical properties were investigated in detail. The optimal sample with the MgO concentration of 7 wt% possesses an energy density of 812 J/cm3 and a resistance temperature coefficient reaches 0.4 × 10−3/°C, which are improved by 8 and 103 %, respectively. Spontaneously, the nonlinear coefficient maintains about 1.15 and the resistivity reaches to 778 Ω cm, increased by 33 %.