2025, Vol. 6, Issue 2, Part B

The main problem in preparing PTCR ceramics with multilayer structures is to reduce the sintering temperature of PTCR ceramics and, at the same time, to raise the PTC effect. We investigated the effect of BaO-B₂O₃-SiO₂-MnO₂ addition as a low temperature sintering additive on the electrical properties of PTCR ceramics prepared by solid state reaction method. To enhance the PTC effect in low temperature sintering, MnO₂ was added into the BaO-B₂O₃-SiO₂ sintering additive, the MnO₂ content varied from 0.02 mol% to 0.08 mol%. The PTCR ceramics adding sintering additives were sintered at temperature range of 970?-1 250?, the room-temperature resistance of PTCR ceramics had a minimum value at the sintering temperature of 1 050?. According to the sintering temperature, the microstructures of PTCR ceramics were investigated using scanning electron microscopy. The PTCR ceramics with BaO-B₂O₃-SiO₂-MnO₂ sintering additive adding 0.06mol% MnO₂ at the sintering temperature of 1 050? results in a relatively low room-temperature resistance and resistance jump of about 10⁴.