Dependence of Temperature Coefficient of Ceramic Linear Resistors on Ceramic Material Synthesis

With the system of ZnO+MgO+Al₂O₃+SiO₂, zinc oxide (ZnO) linear resistors were prepared. The effects of calcination conditions of the ZnO ceramic powder and sintering temperature of the ceramic body on temperature coefficient and resistivity of the ZnO ceramic linear resistors were studied. When the ZnO powder was calcined at 1000 ℃ and the ceramic body was sintered at 1240 ℃, the resistivity of the resistor reached 1165 Ω·cm. Additionally, at a testing temperature of 100 ℃, the temperature coefficient of the ZnO linear resistors initially increased and then decreased with increasing resistivity. Moreover, the primary raw material ZnO in the ceramic powder, after calcination, resulted in a lower temperature coefficient of linear resistance. Specifically, when the ZnO was calcined at 800 ℃ and the ceramic body was sintered at 1240 ℃, temperature coefficient of the resistors achieved the lowest value at 520 ppm·℃^-1.