Electrical properties comparison of NTC thermistors prepared from nanopowders and mixed-oxide process

We have synthesized and studied the effects of cobalt doping on the electrical properties of NTC thermistors with composition of NiMn2-xCoxO4 (x= 0.0, 0.4, 0.8, 1.2, 1.6). The electrical properties of NTC thermistors prepared from nanopowders by gel auto-combustion and mixed-oxide process have been compared. The measured results indicated that the fluctuation of B values for samples made from nanopowders is less than that for the samples prepared from mixed oxide method. As the electrical properties of these ceramics are depend too much on grain size. The samples made from nanopowders have smaller grain size since the sintering time was chosen to be the same for both samples.

کلیدواژه ها:

NTC thermistors ، nanopowders ، material constants