CN109616268A - A kind of preparation method of composite high temperature thermistor - Google Patents

Abstract

Translated fromChinese

本发明涉及一种复合型高温热敏电阻的制备方法，该方法以碳酸钙、三氧化二镧、三氧化二铬、氧化镁和三氧化二铝为原料，其结构由同构于LaCrO₃的La_1‑xCa_xCrO₃钙钛矿相和MgAl₂O₄尖晶石相组成，0.05≤x≤0.2，通过陶瓷工艺经原材料混合研磨、预烧研磨制得单相粉体、两相混合研磨、压片成型、冷等静压成型、高温烧结、切片、上下表面涂覆和烧渗铂浆电极、划片、焊接铂金丝引线，即得到复合型高温热敏电阻。通过本发明所述方法获得的复合型高温热敏电阻的电性能稳定，一致性好，在温度‑50℃‑900℃范围具有明显的负温度系数特性，适合制造热敏电阻型高温温度传感器，可满足汽车工业高温测控需求。

The invention relates to a preparation method of a composite high-temperature thermistor. The method uses calcium carbonate, lanthanum trioxide, chromium oxide, magnesium oxide and aluminum oxide as raw materials, and its structure is composed of isostructural LaCrO₃ . La_1‑x Ca_x CrO₃ perovskite phase and MgAl₂ O₄ spinel phase, 0.05≤x ≤ 0.2, single-phase powder, two-phase mixing are obtained by mixing and grinding raw materials, pre-sintering and grinding through ceramic technology Grinding, tablet forming, cold isostatic pressing, high temperature sintering, slicing, coating the upper and lower surfaces and sintering platinum paste electrodes, scribing and welding platinum wire leads to obtain a composite high temperature thermistor. The composite high-temperature thermistor obtained by the method of the invention has stable electrical properties, good consistency, and has obvious negative temperature coefficient characteristics in the temperature range of 50°C-900°C, and is suitable for manufacturing thermistor type high temperature temperature sensors. It can meet the high temperature measurement and control needs of the automotive industry.

Description

A kind of preparation method of compound high-temperature thermistor

Technical field

The present invention relates to a kind of preparation methods of compound high-temperature thermistor, and the thermistor is in -50 DEG C of -900 DEG C of modelsThere is apparent negative temperature coefficient feature in enclosing, be suitable for manufacture thermosensitive resistance type high temperature sensor, belong to temperature sensingDevice field.

Background technique

Sensing element and sensor are one of the three big pillars of electronics and information industry that country determines, have been considered as mostElectronic technology product with development prospect, developing Sensitive Apparatus, status has act foot light in the world to China's electronics industry is promotedThe effect of weight.Thermistor has high sensitivity, good reliability, lower-price characteristic, has been widely used in daily lifeThe temperature sensing and control of electrical appliance and industrial equipment.The main application of negative temperature coefficient (NTC) thermistor includes: that temperature is mendedIt repays, inhibit surge current, therm-param method.To meet auto industry high temperature (> 300 DEG C) observing and controlling demand, high-temperature heat-sensitive electricityResistance has become the new development trend in NTC thermistor field and research hotspot.

MgAl₂O₄With very high fusing point (2130 DEG C), and with excellent mechanical behavior under high temperature and resistant to chemical etching etc. excellentPoint has been widely used as the fields such as refractory material, moisture sensor and crystalline ceramics.

LaCrO₃Series ceramic material has excellent electric conductivity, oxidation-reduction stability and heat-resisting quantity, is that perovskite is diluteStructure material the most stable in native oxide, be widely used in magnetic fluid electrode, solid oxide fuel cell cathode material,Link material and high-temperature refractory etc..

Summary of the invention

The object of the present invention is to provide a kind of preparation method of compound high-temperature thermistor, the high-temperature thermistorsUsing calcium carbonate, lanthanum sesquioxide, chrome green, magnesia and aluminum oxide as raw material, structure is mainly by being isomorphic toLaCrO₃La_1-xCa_xCrO₃Perovskite Phase and MgAl₂O₄Spinel composition, by ceramic process through raw material mixed grinding,Single-phase powder, two-phase mixtures grinding, compression molding, cold isostatic compaction, high temperature sintering, slice, upper following table is made in pre-burning grindingFace coating and burning infiltration platinum electrode, scribing weld platinum wire lead to get compound high-temperature thermistor is arrived.Through the inventionThe electric performance stablity for the compound high-temperature thermistor that the method obtains, consistency is good, the use of warm area is -50 DEG C -900 DEG C,Material constant is B_{-50℃/200℃}=1600K-3800K, B_{200℃/800℃}=200K-2800K, -50 DEG C of resistivity of temperature are 10²Ωcm-10⁷Ω cm, 900 DEG C of resistivity of temperature are 30 Ω cm-200 Ω cm, which is suitble to manufacture thermistorType high temperature sensor can meet auto industry high temperature observing and controlling demand.

A kind of preparation method of compound high-temperature thermistor of the present invention, this method is with calcium carbonate, three oxidations twoLanthanum, chrome green, magnesia and aluminum oxide are raw material, and structure is by being isomorphic to LaCrO₃La_1-xCa_xCrO₃PerovskitePhase and MgAl₂O₄The compound phase composition of Spinel, wherein 0.05≤x≤0.2, concrete operations follow these steps to carry out:

A, La is pressed_1-xCa_xCrO₃Composition weigh calcium carbonate, lanthanum sesquioxide, chrome green respectively and mixed, will mixThe raw material of conjunction is placed in agate mortar and grinds 6-10 hours, calcines 1-6 hours at 1000 DEG C-1200 DEG C of temperature, obtains sameStructure is in LaCrO₃La_1-xCa_xCrO₃Powder；

B, MgAl is pressed₂O₄Composition weigh magnesia respectively and aluminum oxide is mixed, mixed raw material is placed in MaIt is ground 6-10 hours in Nao mortar, is calcined 1-6 hours at 1100 DEG C-1400 DEG C of temperature, obtain MgAl₂O₄Powder；

C, by La obtained in step a_1-xCa_xCrO₃The MgAl that powder and step b are obtained₂O₄Powder 0.3- in molar ratio0.6:0.7-0.4 is mixed, and mixed powder is ground 10-20 hours in the agate mortar, obtains compound high-temperature heat-sensitiveResistance powder；

D, adhesive polyethylene ketone is added in the compound high-temperature thermistor powder for obtaining step c, in 20Kg/cm²'sPressure is pressed, and molding block materials are carried out isostatic cool pressing, in the case where pressure is 300MPa pressure maintaining 1 minute, thenIn -1700 DEG C of sintering 4-10 hours of 1500 DEG C of temperature, compound high-temperature thermistor ceramics are made；

E, the compound high-temperature thermistor ceramics for being sintered step d are starched by slice, upper and lower surface coating and burning infiltration platinumElectrode, scribing obtain high-temperature thermistor chip；

F, the thermistor chip upper and lower surface for obtaining step e welds platinum wire, and obtaining warm area is -50 DEG C -900DEG C, material constant B_{-50℃/200℃}=1600K-3800K, B_{200℃/800℃}=200K-2800K, -50 DEG C of resistivity of temperature are 10²Ωcm-10⁷Ω cm, 900 DEG C of resistivity of temperature are the compound high-temperature thermistor of 30 Ω cm-200 Ω cm.

A kind of preparation method of compound high-temperature thermistor of the present invention, this method utilize La_1-xCa_xCrO₃Calcium titaniumMine phase and MgAl₂O₄Spinel is compound to be prepared for compound high-temperature thermistor, in terms of innovative point mainly has following two:

(1)Ca²⁺Ion doping LaCrO₃Material forms the second phase of low melting point during the sintering process, and this liquid phase promotesSolid phase mass transfer improves the consistency of thermistor ceramics.

(2) pass through two-phase complex technique combination Ca²⁺High-temperature thermistor electrical property is adjusted in ion doping, and then realize-50 DEG C -900 DEG C wide warm area high temperature application.

The compound high-temperature thermistor -50 DEG C -900 DEG C have apparent negative temperature coefficient feature, electric performance stablity,Consistency is preferable, and ageing properties are stablized, and is suitble to manufacture thermosensitive resistance type high temperature sensor, can meet auto industry high temperature sideControl demand.

Detailed description of the invention

Fig. 1 is X ray diffracting spectrum of the invention.

Specific embodiment

Embodiment 1

A, La is pressed_0.95Ca_0.05CrO₃Composition weigh calcium carbonate, lanthanum sesquioxide, chrome green respectively and mixed,Mixed raw material is placed in agate mortar and is ground 6 hours, is calcined 1 hour at 1000 DEG C of temperature, obtains being isomorphic to LaCrO₃La_0.95Ca_0.05CrO₃Powder；

B, MgAl is pressed₂O₄Composition weigh magnesia respectively and aluminum oxide is mixed, mixed raw material is placed in MaIt is ground 6 hours in Nao mortar, is calcined 1 hour at 1100 DEG C of temperature, obtain MgAl₂O₄Powder；

C, by La obtained in step a_0.95Ca_0.05CrO₃The MgAl obtained with step b₂O₄Powder 0.3:0.7 in molar ratioIt is mixed, mixed powder is ground 10 hours in the agate mortar, obtain compound high-temperature thermistor powder；

D, adhesive polyethylene ketone is added in the compound high-temperature thermistor powder for obtaining step c, in 20Kg/cm²'sPressure is pressed, and molding block materials are carried out isostatic cool pressing, in the case where pressure is 300MPa pressure maintaining 1 minute, thenIt is sintered 4 hours in 1700 DEG C of temperature, compound high-temperature thermistor ceramics is made；

E, the compound high-temperature thermistor ceramics for being sintered step d are starched by slice, upper and lower surface coating and burning infiltration platinumElectrode, scribing obtain high-temperature thermistor chip；

F, the thermistor chip upper and lower surface for obtaining step e welds platinum wire, and obtaining warm area is -50 DEG C -900DEG C, material constant B_{-50℃/200℃}=3800K, B_{200℃/800℃}=2800K, -50 DEG C of resistivity of temperature are 10⁷Ω cm, temperature 900DEG C resistivity is the compound high-temperature thermistor of 200 Ω cm.

Embodiment 2

A, La is pressed_0.9Ca_0.1CrO₃Composition weigh calcium carbonate, lanthanum sesquioxide, chrome green respectively and mixed, willMixed raw material is placed in agate mortar and grinds 8 hours, calcines 2 hours at 1100 DEG C of temperature, obtains being isomorphic to LaCrO₃'sLa_0.9Ca_0.1CrO₃Powder；

B, MgAl is pressed₂O₄Composition weigh magnesia respectively and aluminum oxide is mixed, mixed raw material is placed in MaIt is ground 8 hours in Nao mortar, is calcined 2 hours at 1300 DEG C of temperature, obtain MgAl₂O₄Powder；

C, by La obtained in step a_0.9Ca_0.1CrO₃The MgAl obtained with step b₂O₄Powder in molar ratio 0.4:0.6 intoRow mixing, mixed powder is ground 16 hours in the agate mortar, obtains compound high-temperature thermistor powder；

D, adhesive polyethylene ketone is added in the compound high-temperature thermistor powder for obtaining step c, in 20Kg/cm²'sPressure is pressed, and molding block materials are carried out isostatic cool pressing, in the case where pressure is 300MPa pressure maintaining 1 minute, thenIt is sintered 6 hours in 1600 DEG C of temperature, compound high-temperature thermistor ceramics is made；

E, the compound high-temperature thermistor ceramics for being sintered step d are starched by slice, upper and lower surface coating and burning infiltration platinumElectrode, scribing obtain high-temperature thermistor chip；

F, the thermistor chip upper and lower surface for obtaining step e welds platinum wire, and obtaining warm area is -50 DEG C -900DEG C, material constant B_{-50℃/200℃}=2400K, B_{200℃/800℃}=1600K, -50 DEG C of resistivity of temperature are 10⁵Ω cm, temperature 900DEG C resistivity is the compound high-temperature thermistor of 48 Ω cm.

Embodiment 3

A, La is pressed_0.8Ca_0.2CrO₃Composition weigh calcium carbonate, lanthanum sesquioxide, chrome green respectively and mixed, willMixed raw material is placed in agate mortar and grinds 10 hours, calcines 6 hours at 1200 DEG C of temperature, obtains being isomorphic to LaCrO₃'sLa_0.8Ca_0.2CrO₃Powder；

B, MgAl is pressed₂O₄Composition weigh magnesia respectively and aluminum oxide is mixed, mixed raw material is placed in MaIt is ground 10 hours in Nao mortar, is calcined 6 hours at 1400 DEG C of temperature, obtain MgAl₂O₄Powder；

C, by La obtained in step a_0.8Ca_0.2CrO₃The MgAl obtained with step b₂O₄Powder in molar ratio 0.6:0.4 intoRow mixing, mixed powder is ground 20 hours in the agate mortar, obtains compound high-temperature thermistor powder；

D, adhesive polyethylene ketone is added in 20Kg/cm in the compound high-temperature thermistor powder for obtaining step c²PressurePower is pressed, by molding block materials carry out isostatic cool pressing, pressure be 300MPa under pressure maintaining 1 minute, then in1500 DEG C of temperature are sintered 10 hours, and compound high-temperature thermistor ceramics are made；

E, the compound high-temperature thermistor ceramics for being sintered step d are starched by slice, upper and lower surface coating and burning infiltration platinumElectrode, scribing obtain high-temperature thermistor chip；

F, the thermistor chip upper and lower surface for obtaining step e welds platinum wire, and obtaining warm area is -50 DEG C -900DEG C, material constant B_{-50℃/200℃}=1600K, B_{200℃/800℃}=200K, -50 DEG C of resistivity of temperature are 10²Ω cm, 900 DEG C of temperatureResistivity is the compound high-temperature thermistor of 30 Ω cm.

Claims (1)

Translated fromChinese

1.一种复合型高温热敏电阻的制备方法，其特征在于该方法以碳酸钙、三氧化二镧、三氧化二铬、氧化镁和三氧化二铝为原料，其结构由同构于LaCrO₃的La_1-xCa_xCrO₃钙钛矿相和MgAl₂O₄尖晶石相的复合相组成，其中0.05≤x≤0.2，具体操作按下列步骤进行：1. a preparation method of a composite type high temperature thermistor is characterized in that the method is raw material with calcium carbonate, lanthanum trioxide, chromium oxide, magnesium oxide and aluminum oxide, and its structure is composed of isomorphism in LaCrO The composite phase composition of the La_1-x Ca_x CrO₃ perovskite phase and the MgAl₂ O₄ spinel phase of₃ , wherein 0.05≤x≤0.2, the specific operation is carried out according to the following steps:a、按La_1-xCa_xCrO₃的组成分别称取碳酸钙、三氧化二镧、三氧化二铬进行混合，将混合的原料置于玛瑙研钵中研磨6—10小时，在温度1000℃—1200℃下煅烧1-6小时，得到同构于LaCrO₃的La_1-xCa_xCrO₃粉体；a, according to the composition of La_1-x Ca_x CrO₃ respectively weigh calcium carbonate, lanthanum trioxide, and dichromic oxide and mix, and the mixed raw materials are placed in an agate mortar and ground for 6-10 hours, at a temperature of 1000 calcined at ℃-1200 ℃ for 1-6 hours to obtain La_1-x Ca_x CrO₃ powder isostructural to LaCrO₃ ;b、按MgAl₂O₄的组成分别称取氧化镁和三氧化二铝进行混合，将混合的原料置于玛瑙研钵中研磨6—10小时，在温度1100℃—1400℃下煅烧1—6小时，得到MgAl₂O₄粉体；b. According to the composition of MgAl₂ O₄ , respectively weigh magnesium oxide and aluminum oxide and mix them. The mixed raw materials are placed in an agate mortar and ground for 6-10 hours, and calcined at a temperature of 1100 ℃-1400 ℃ for 1-6 hours. hours to obtain MgAl₂ O₄ powder;c、将步骤a中得到的La_1-xCa_xCrO₃粉体和步骤b得到的MgAl₂O₄粉体按摩尔比0.3-0.6:0.7-0.4进行混合，将混合的粉体在玛瑙研钵中研磨10-20小时，得到复合型高温热敏电阻粉体；c. Mix the La_1-x Ca_x CrO₃ powder obtained in step a and the MgAl₂ O₄ powder obtained in step b in a molar ratio of 0.3-0.6:0.7-0.4, and grind the mixed powder in agate Grinding in a bowl for 10-20 hours to obtain composite high temperature thermistor powder;d、将步骤c得到的复合型高温热敏电阻粉体加入粘合剂聚乙烯酮，在20Kg/cm²的压力进行压制成型，将成型的块体材料进行冷等静压，在压强为300MPa下保压1分钟，然后于温度1500℃-1700℃烧结4-10小时，制得复合型高温热敏电阻陶瓷；d, adding the composite high^- temperature thermistor powder obtained in step c into the adhesive polyvinyl ketone, and carrying out compression molding at a pressure of 20Kg/cm , and carrying out cold isostatic pressing of the formed bulk material, at a pressure of 300MPa Hold the pressure for 1 minute, and then sinter at a temperature of 1500℃-1700℃ for 4-10 hours to obtain a composite high temperature thermistor ceramic;e、将步骤d烧结的复合型高温热敏电阻陶瓷经过切片、上下表面涂覆和烧渗铂浆电极、划片，获得高温热敏电阻芯片；e. The composite high-temperature thermistor ceramics sintered in step d are sliced, coated on the upper and lower surfaces, sintered with platinum paste electrodes, and diced to obtain a high-temperature thermistor chip;f、将步骤e获得的热敏电阻芯片上下表面焊接铂金丝，即制得温区为-50℃-900℃，材料常数为B_{-50℃/200℃}＝1600K-3800K，B_{200℃/800℃}＝200K-2800K，温度-50℃电阻率为10²Ωcm-10⁷Ωcm，温度900℃电阻率为30Ωcm-200Ωcm的复合型高温热敏电阻。f. Weld platinum wire on the upper and lower surfaces of the thermistor chip obtained in step e, that is, the temperature range is -50°C-900°C, and the material constant is B_{-50°C/200°C} = 1600K-3800K, B_{200°C/800 ℃} =200K-2800K, temperature-50℃ resistivity is 10² Ωcm-10⁷ Ωcm, temperature 900℃ resistivity is 30Ωcm-200Ωcm composite high temperature thermistor.