Journal of Materials Science, Vol.31, No.10, 2603-2607, 1996
Chemical-Processing and Characterization of Spinel-Type Thermistor Powder in the Mn-Ni-Fe Oxide System
The coprecipitated Mn-Ni-Fe oxalate was prepared from the mixed sulfate solution by optimum pH control. The chemical composition agreed well with that of the starting solution, and the thermal decomposition of the Mn-Ni-Fe oxalate in air below 600 degrees C led to the direct formation of cubic spinel phase with fine particle size. The sinterability of the calcined powder, the stability of cubic spinel phase and the influence of annealing temperature on electrical properties of the sintered bodies, were investigated.