BaTiO_3热敏电阻的低温烧结特性研究

Study on the Low-Temperature-Sintered Properties of BaTiO_3 Thermistor

为了得到低烧结温度、较低室温电阻率的BaTiO3基半导体陶瓷,提出在BaO-B2O3-SiO2-MnO烧结助剂中加入LiF的方法,研究了BaO-B2O3-SiO2-MnO-LiF(BBSML)烧结助剂对Y3+与Nb5+双掺杂BaTiO3基热敏陶瓷的微观结构和正温度系数(PTC)特性的影响。微观结构分析表明:玻璃助剂中LiF的含量能改变晶界相组成,影响样品的烧结特性和室温电阻率。实验结果表明,x(LiF)=5%的BBSML烧结助剂的样品,在1 050℃保温1 h下烧结后,其室温电阻率为151Ω.cm,升阻比为5.6×103。

In order to obtain BaTiO3 based semiconductor ceramics with low sintering temperature and low room-temperature resistivity,a scheme adding LiF into BaO-B2O3-SiO2-MnO sintering aid was proposed in this paper. The effect of BaO-Be O3-MnO-LiF（BBSML） glass additive on the microstructure and positive temperature coefficienl （PTC） features of BaTiOa based thermo-sensitive ceramics with y3^＋ and Nb5^＋ double-doped has been investiga- ted. The analysis of the microstructure showed that the LiF contents in the glass additive could change the crystal boundary phased composition and influence the sintering properties and room-temperature resistivity of samples. The experimental results indicated that the samples with LiF contents of 5% in BBSML sintering aids had the room-tem- perature resistivity of 151 cm and the resistivity jump of 5.6×10^3 after being sintered at 1 050 ℃ and being heat-retained for 1 hour.