阅读说明：本技术 一种镧离子掺杂的深低温热敏电阻材料及制备方法 (Lanthanum ion doped deep low temperature thermistor material and preparation method thereof ) 是由 张惠敏 常爱民 范庆梅 孙家林 王强 刘思学 代树武 于 2019-11-15 设计创作，主要内容包括：本发明公开了一种镧离子掺杂的深低温热敏电阻材料及制备方法,该电阻材料以锰、镍、铁、镧的氧化物为原料,采用固相法进行制备,将混合后的粉体经过煅烧、研磨、烧结制得。与市面上现有的NTC热敏电阻相比,该电阻材料可以在15 K条件下工作。其电性能参数为：R<Sub>70K(The invention discloses a lanthanum ion doped deep low temperature thermistor material and a preparation method thereof, wherein the resistor material is prepared by taking oxides of manganese, nickel, iron and lanthanum as raw materials and adopting a solid phase method, and mixed powder is prepared by calcining, grinding and sintering. Compared with the NTC thermistor on the market, the resistance material can work under the condition of 15K. The electrical performance parameters are as follows: r 70K =160 KΩ∙cm，R 90K = 680K Ω ∙ cm. The temperature measuring interval is between 15K and 280K, and the problems that the low-temperature thermistor has a narrow temperature measuring range and an application range is not wide enough are solved. The thermistor prepared from the material can be applied to the fields of aerospace and other deep low temperatures.)

1. A lanthanum ion doped deep low-temperature thermistor material is characterized in that the material is made of MnO₂、NiO、Fe₂O₃And La₂O₃As raw material, in molar ratio MnO₂:NiO: Fe₂O₃: La₂O₃And the powder is prepared by ball milling, calcining, grinding, molding and high-temperature sintering, wherein the ratio of the powder to the powder is 0.45-2:0.8-3:0.1-0.6: 1-4.15.

2. The method for preparing a lanthanum ion doped deep low temperature thermistor material according to claim 1, characterized by comprising the following steps:

a. powder proportioning: in MnO₂、NiO、Fe₂O₃And La₂O₃As raw material, in molar ratio MnO₂:NiO: Fe₂O₃: La₂O₃Weighing the materials in a ratio of 0.45-2:0.8-3:0.1-0.6:1-4.15, respectively, placing the materials into a polytetrafluoroethylene tank for ball milling for 8-12 h, and drying the materials at the temperature of 100-150 ℃ to obtain Mn-Ni-Fe-La-O mixed powder, wherein the mixing mass ratio of agate balls, powder, dispersant acetone and ether in the polytetrafluoroethylene tank is 1-4:1:1, and the mixing volume ratio of dispersant acetone and ether is 1:9-9: 1;

b. and (3) calcining: b, calcining the Mn-Ni-Fe-La-O mixed powder obtained in the step a at the temperature of 900-1100 ℃ for 1-4h to obtain Mn-Ni-Fe-La-O powder with a spinel structure;

c. mixing and grinding: b, putting the calcined spinel Mn-Ni-Fe-La-O powder in the step b into an agate mortar for grinding for 2-6 h;

d. molding: c, performing cold isostatic pressing on the powder compounded in the step c for 140-175 s under 280-350 MP, and then forming;

e. and (3) sintering: placing the shaped block of step d in a container containing MnO₂、Fe₂O₃、La₂O₃One or two or three kinds of Al₂O₃Sintering the powder at 1150-1300 ℃ for 1-4h to obtain the lanthanum ion doped deep low temperature thermistor material.

Technical Field

The invention relates to a lanthanum ion doped deep low temperature thermistor material and a preparation method thereof, and the material is suitable for the fields of deep low temperature, spaceflight and outer space temperature detection based on the electrical performance parameters of the novel material.

Background

Negative Temperature Coefficient (NTC) thermistors can be classified into the following three types according to the actual medical temperature range: low temperature zone (0-213.15K), normal temperature zone (213.15-623.15K) and high temperature zone (623.15-1273.15K). At present, most of Negative Temperature Coefficient (NTC) thermistors sold in the market are of a normal temperature type, few and few low-temperature type resistors are available, even if some products have low-temperature detection functions, the requirements of aerospace and deep sea temperature measurement cannot be met, the fundamental reason is that when the external temperature environment is extremely low, the resistance value of most of resistors tends to infinity, and the transmission of electrical signals is difficult to realize.

Disclosure of Invention

The invention aims to provide a lanthanum ion doped deep low temperature thermistor material and a preparation method thereof, wherein the material is made of MnO₂，NiO，Fe₂O₃And La₂O₃The La-doped deep low-temperature thermistor material is prepared by mixing the raw materials, performing ball milling, calcining, grinding, molding and high-temperature sintering, and the low-temperature resistance of the resistor device and the B value in a low-temperature measurement range are reduced by increasing the La ion content. When the La ion content reaches the maximum, the testing temperature can be as low as 15K, R_77K＝160KΩ·cm，B_77/90290.38K, the lowest of the measured temperature, resistance, and B value is achieved. Meanwhile, the temperature measuring range of the prepared thermistor can be from 15K to 280K, so that the core problems of narrow temperature measuring range and small application range of MF5602 products are solved. The material has small fluctuation range of the B value, namely B_77/90The material system is quite stable and is consistent with the military requirement when being 290.38-311.63K.

The invention relates to a lanthanum ion doped deep low temperature thermistor material, which is made of MnO₂、NiO、Fe₂O₃And La₂O₃As raw material, in molar ratio MnO₂:NiO:Fe₂O₃:La₂O₃0.45-2:0.8-3:0.1-0.6:1-4.15, and is prepared by ball milling, calcining, grinding, molding and high-temperature sintering.

The preparation method of the lanthanum ion doped deep low temperature thermistor material comprises the following steps:

a. powder proportioning: in MnO₂、NiO、Fe₂O₃And La₂O₃As raw material, in molar ratio MnO₂:NiO:Fe₂O₃:La₂O₃Weighing 0.45-2:0.8-3:0.1-0.6:1-4.15 respectively, placing the materials into a polytetrafluoroethylene tank for ball milling for 8-12 h, and drying at the temperature of 100-150 ℃ to obtain Mn-Ni-Fe-La-O mixed powder, wherein the mixing mass ratio of agate balls, powder, dispersant acetone and ether in the polytetrafluoroethylene tank is 1-4:1:1, and the mixing volume ratio of dispersant acetone and ether is 1:9-9: 1;

b. and (3) calcining: b, calcining the Mn-Ni-Fe-La-O mixed powder obtained in the step a at the temperature of 900-1100 ℃ for 1-4h to obtain Mn-Ni-Fe-La-O powder with a spinel structure;

c. mixing and grinding: b, putting the calcined spinel Mn-Ni-Fe-La-O powder in the step b into an agate mortar for grinding for 2-6 h;

d. molding: c, performing cold isostatic pressing on the powder compounded in the step c for 140-175 s under 280-350 MP, and then forming;

e. and (3) sintering: placing the shaped block of step d in a container containing MnO₂、Fe₂O₃、La₂O₃One or two or three kinds of Al₂O₃Sintering the powder at 1150-1300 ℃ for 1-4h to obtain the lanthanum ion doped deep low temperature thermistor material.

The invention relates to a lanthanum ion doped deep low temperature thermistor material and a preparation method thereof, and the material has the following characteristics:

1. the lowest test temperature can reach 15K;

2. the temperature test has wide application range: 15-280K;

3、B_77/90the value and the fluctuation range thereof are small: b is_77/90290.38-311.63K, the material system is stable;

4. lower resistance R at low temperature_77K＝160KΩ·cm。

Detailed Description

The present invention will be described in further detail with reference to examples, which are not intended to limit the scope of the present invention.