The utility model relates to a thermistance material with high uniformity and
negative temperature coefficient. The main formulation is one in the six systems of Mn-Ni-Cu, Mn-Co-Cu, Mn-Co-Ni-Cu, Mn-Co-Fe-Cu, Mn-Co-Ni or Mn-Co-Fe. The combination of at least two of the oxides as CaO, ZnO, SiO2, Al2O3, Fe2O3, MgO, Cr2O3, TiO2, Sb2O3, Bi2O3, SrO, Nb2O5 and B2O3 are added to the main formulation. The utility model also relates to a preparation method for preparing the thermistance material with high uniformity and
negative temperature coefficient, comprising the following steps: mixture making, primary
wet milling,
drying, calcining, and secondary
wet milling,
drying and granulating, pressing and forming, and
sintering. The utility model has the advantages that: the thermistance material with
negative temperature coefficient (NTCR) made by the method has high uniformity and high
repeatability; the
specific resistance uniformity of the same batch material is all better than plus or minus 1%; the
specific resistance error of different batches does not exceed plus or minus 2%; the error of value B does not exceed plus or minus 1%; the utility model is suitable for
mass and large-scale production.