Influence of the sintering process on the PTCR effect of chip-type Ba1.022–xSmxTiO3 ceramics prepared by the reduction sintering-reoxidation method

• Published in: Journal of materials science. Materials in electronics Vol. 25; no. 2; pp. 1105 - 1111
• Main Authors: Cheng, Xuxin, Zhou, Dongxiang, Fu, Qiuyun, Cui, Haining
• Format: Journal Article
• Language: English
• Published: Boston Springer US 2014
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Materials Science; Optical and Electronic Materials; High Sinter Temperature; Positive Temperature Coefficient; Increase Sinter Temperature; Breakdown Voltage; Sinter Temperature
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-013-1695-z

We investigated the effects of sintering temperature and reoxidation annealing on the positive temperature coefficient of resistance (PTCR) effect of Ba 1.022– x Sm x TiO 3 ceramics that were sintered at 1,180–1,260 °C for 30 min in a reducing atmosphere and reoxidized at 800 °C for 1 h. Results indicated that the room-temperature (RT) resistivity and resistance jump of the ceramics decreased with increasing sintering temperature; moreover, the samples exhibited a remarkable PTCR effect with a resistance jump of 3.3 orders of magnitude and achieved a low RT resistivity of 374.4 Ω cm at a lower sintering temperature. Furthermore, the higher grain-boundary resistivity of the ceramics obtained at a high reoxidation temperature after sintering at low temperature was estimated using an impedance analyzer. In addition, the voltage versus current behavior was investigated in present study.