High evenness negative temperature coefficient heat-sensitive resistance material and its preparation method

Abstract

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.

Description

(1) Technical field [0001] The invention relates to a high uniformity negative temperature coefficient thermistor material and a preparation method thereof, belonging to the field of electronic ceramic materials and preparation. (2) Background technology [0002] Negative temperature coefficient thermistors have been widely used in various fields of temperature measurement, control, temperature compensation, protection of circuits and electronic components, and flow velocity, flow, and ray measurement. There are many types and structures. However, in NTCR manufacturing, the problem of product consistency and batch-to-batch repeatability has not yet been fundamentally resolved. NTCR thermosensitive material is a multiphase structure composed of grains, grain boundaries and pores. The main factors affecting the consistency of the material are the deviation of the composition, the uncontrollable doping during the process and the instability of the preparation environment. For...

AI Technical Summary

Problems solved by technology

Foreign companies mostly use high-purity raw materials and strictly control the production environment to improve the consistency and repeatability of materials, so that the error of resistivity is controlled within (1-1.5)%, and the error of B value is about (0.5-1.0)%. However, the process conditions are harsh and the cost of material preparation is high