High-quality Mn-Co-Ni oxalate powder was prepared in a mixed solvent of water and ethanol by an improved oxalate coprecipitation approach. The as-prepared oxalate powder appears a controlled homogeneous morphology and narrower particle size distribution by conveniently adjusing the ratio of water to ethanol. The ceramic, moulded with the high quality oxalate precursor, could be densified at a lower temperature of 1150 ℃; and also exhibits a higher density and the more homogeneous microstructure with smaller grain sizes of 2-5 μm. Accordingly, the NTC thermistors fabri-cated from the ceramic have a better yield as compared to the traditional method.
展开▼
