Studies on the properties of Ni0.6Cu0.4Mn2O4 NTC ceramic due to Fe doping

The influence of the Fe on the microstructure, electrical and dielectric properties of Ni0.6Cu0.4FeyMn2−yO4 (0.1 ≤ y ≤ 0.5) negative temperature coefficient (NTC) thermistors prepared by well known simple chemical co-precipitation method were studied. The replacement of manganese by iron plays an important role in changing the lattice parameter, X-ray density, sintered density, porosity, DC resistivity at different temperatures and dielectric properties at different frequencies. The X-ray and sintered density increased linearly and porosity decreased with iron. The room temperature resistivity of nickel copper manganite NTC ceramic decreased from 1 MΩ cm to 68 KΩ cm and dielectric constant increased from ∼9 × 107 to 1.5 × 109 at 20 Hz as iron content increased.