论文部分内容阅读
In this paper, the Co-Mn-Fe-O (CMF) ceramic materials are prepared by the high energy ball milling process,and the phase structures, microstructures and electrical stability of CMF ceramics are investigated and characterized by the XRD, SEM, and electrical measurements.XRD results show that all the CMF ceramic samples are the same single cubic spinel phase with the sintering temperature increasing from 1100℃ to 1250℃.SEM images present that CMF ceramic materials have high density above the sintering temperature of 1150℃.The thermal sensitive properties with high values of ρ25, B25/50, and Ea of CMF ceramics at different sintering temperatures are in the range of 1119-2245 Ω · cm, 3721 ~3994 K, and 0.3166 ~0.3445 eV, respectively.In particular, the samples sintered at 1200℃ have the higher electrical stability, and the relative resistance drift is as low as 0.1% after aging at 125℃ for 500 h.The CMF thermistors exhibit good stability, which have practical value for negative temperature coefficient (NTC) thermistor applications.