25.07.2016 | Ausgabe 12/2016
Preparation and characterization of Mn1.2Co0.6Ni1.2O4 NTC ceramic materials by rheological phase reaction method
Abstract
Mn1.2Co0.6Ni1.2O4 negative temperature coefficient thermistor materials were prepared by the rheological phase reaction method. The effect of sintering temperature on the microstructure and electrical properties of Mn1.2Co0.6Ni1.2O4 ceramic materials was systemically investigated and characterized by XRD, SEM, and electrical measurement. The results indicate that all the ceramic materials show the single cubic spinel phase, as well as the material constant B values and ρ25 of the Mn1.2Co0.6Ni1.2O4 thermistors are in the range of 3199–3343 K, 593–1299 Ω cm, respectively, as the sintering temperature increases from 1100 to 1250 °C. At the sintering temperature of 1200 °C, the ceramic samples have the best thermal stability, that is the lowest resistivity drift rate (ΔR/R) of 0.43 %. Therefore, Mn1.2Co0.6Ni1.2O4 ceramic materials prepared by the rheological phase reaction method meet the demands of market development and have potential in the industrial applications.