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CN1052804C - Manufacturing method of positive temperature coefficient ceramic thermistor - Google Patents

Manufacturing method of positive temperature coefficient ceramic thermistor Download PDF

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Publication number
CN1052804C
CN1052804C CN95111649A CN95111649A CN1052804C CN 1052804 C CN1052804 C CN 1052804C CN 95111649 A CN95111649 A CN 95111649A CN 95111649 A CN95111649 A CN 95111649A CN 1052804 C CN1052804 C CN 1052804C
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temperature coefficient
manufacturing
positive temperature
carbonate
batching
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CN1137679A (en
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张纪才
雷皙钓
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DADI COMMUNICATION ELECTRONIC
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Abstract

The present invention relates to a method for manufacturing a thermistor made of powdered semiconductor ceramic material with positive temperature coefficient. It is based on the existing sintering technique, and adds manganese dioxide (MnO) into the first material2) And antimony (Sb) and niobium (Nb) which are double donors; and with strontium carbonate (SrCO)3) Substituted part of barium carbonate (BaCO)3) (ii) a In the second compounding, lead titanate (PbTiO) is added3) And is sintered through a certain sintering process. The advantages are that: low sintering temperature, low resistivity, high voltage resistance, strong current impact resistance and high sintering resistance hit rate, and is suitable for mass production.

Description

Production process for positive temp. coefficient ceramic thermal resistor
The present invention relates to the manufacture method of the thermistor that a kind of powder semiconductor ceramic material with positive temperature coefficient constitutes.
Semistor (hereinafter to be referred as PTC resistance) is a kind of semiconductive ceramic element, mainly can be by barium titanate (BaTiO 3), strontium carbonate (SrCO 3), calcium carbonate (CaCO 3), lead oxide (Pbo) and titanium dioxide (TiO 2) wait ceramic material to constitute, by adding alms giver's additive antimony (Sb) and niobium trace rare-earth element and modified materials aluminium oxide (Al such as (Nb) 2O 3), manganese oxide (MnO 2) wait mineral matter.Under 1350 ℃ temperature,, obtain low, the withstand voltage high ptc material of resistivity with the Si-Mo rod high temperature furnace through strict intensification, temperature-fall period.Usually adopt at the semiconductor ceramic material barium titanate, through twice batching, added the pure water ball milling 48 hours after the batching for the first time, oven dry back pre-burning to 1150 ℃ two hours after the batching, is dried after 48 hours through ball milling for the second time, carries out sintering behind the granulating and forming.Prepare burden the described first time is at semiconductor ceramic material barium titanate (BaTiO 3) in be added into the trace element and the calcium carbonate (CaCO of alms giver's additive 3), with strontium carbonate (SrCO 3) replacement part brium carbonate (BaCO 3).Prepare burden the described second time is to add aluminium oxide (AlO in the batching for the first time 3), silicon dioxide (SiO 2), titanium oxide (TiO 2), lithium carbonate (Li 2CO 3), manganese dioxide (MnO 2).At present, adopt domestic raw materials to make below the resistivity 30 Ω Cm, the withstand voltage 150V/mm that is higher than, temperature coefficient is more than 15%, the PTC semiconductive ceramic thermistor that has withstand voltage rush of current simultaneously is quite difficult, and general sintering Curie point is at the barium titanate (BaTiO below 120 ℃ 3) optimum temperature of semiconductive ceramic is about 1350 ℃, high like this sintering temperature is very unfavorable to the useful life of Elema high temperature furnace.
The purpose of this invention is to provide a kind of manufacture method that adopts domestic raw materials to make low-resistivity, high withstand voltage PTC thermistor;
Technical scheme of the present invention is: also will add manganese dioxide (MnO in the above-mentioned first time in the batching 2); Described alms giver's additive is two alms giver's antimony (Sb) and niobium (Nb); And with strontium carbonate (SrCO 3) replacement part brium carbonate (BaCO 3);
The addition of described pair of alms giver's antimony (Sb) and niobium (Nb) is Sb+Nb ≈ 0.11%md.
Calcium carbonate (CaCO 3) addition be 0.04-0.05mol.
Strontium carbonate (SrCO 3) addition be 0.07-0.2mol.In preparing burden the above-mentioned second time, increase lead titanates (PbTiO again 3), its addition is 5-8%wt, described aluminium oxide (AlO 3) addition be 0.2-0.25%wt, the addition of described silica (SiO2) is 0.3-0.4wt, described lithium carbonate (LiCO 3) addition be 0.03-0.04%wt.
Described sintering process is: (1). be warmed up to 800 ℃ and kept 40 minutes to arrange sticking speed (25 ℃------→ 500 ℃------→ 800 ℃) by room temperature (25 ℃).(2). be warmed up to 1150 ℃ with 300 ℃ speed per hour and kept 40 minutes.(3). be warmed up to 1295-1300 ℃ with 300 ℃ speed per hour and kept 70-90 minute.(4). cool to 1000 ℃ with 250-300 ℃ speed per hour, close stove and naturally cool to below 200 ℃ and comes out of the stove, sintering goes out the PTC ceramics.
Advantage of the present invention is: (1) sintering temperature low (1295-1310 ℃) only can be through the row sintering with general silicon carbide rod furnace.(2) low, the withstand voltage height of resistivity, (φ 5.8 * 2 resistor disc resistances be that 12 Ω are withstand voltage reach more than the 400V (AC)).(3) anti-rush of current strong (seeing attached list).(4) the sintering resistance shoots straight, and burns 3000 in every stove, and its resistance hit rate can reach more than 95%.(5). be suitable for a large amount of productions.
Accompanying drawing is a sintering process curve chart of the present invention;
Most preferred embodiment of the present invention is: batching is to adopt at semiconductor ceramic material barium titanate (BaTiO for the first time 3) middle two alms givers' trace element antimony (Sb) and the niobium (Nb) of adding, to reduce the purpose of semiconductive ceramic resistivity, its addition is Sb+Nb ≈ 0.11% md, interpolation 0.07-0.2mol strontium carbonate (SrCO 3) replacement part brium carbonate (BaCO 3) rise and regulate semiconductive ceramic Curie point and the growth of control ceramic crystalline grain, improve the compressive resistance effect; Add 0.02-0.006mol manganese oxide (MnO 2) improve the ptc characteristics of pottery, added the pure water ball milling then 48 hours, 1150 ℃ of oven dry back pre-burnings two hours.Prepare burden for the second time (promptly mixing), in batching, add the lead titanates (PbTiO of 5-8%wt 3), in order to reduce ceramic sintering temperature, improve the density of ceramic material, improve the withstand voltage and anti-rush of current characteristic of material, regulate ceramic Curie point, add 0.2-0.25%wt aluminium oxide (Al 2O 3), 0.3-0.4%wt silicon dioxide (SiO 2), 0.01mol titanium oxide (TiO 2), 0.03-0.04%wt lithium carbonate (Li 2CO 3), make it when sintering, form liquid phase, absorption is to the ceramic semiconductors objectionable impurities, reduce the ceramic resistor rate and also can play the growth of control ceramic crystalline grain simultaneously, improve the effect of positive temperature coefficient sensitive characteristic, original manganese dioxide is more evenly distributed the powder master through twice ball milling in the batching, be beneficial to and improve sintering resistance hit rate, additive in preparing burden for the second time all adds with weight ratio, can guarantee the reproducibility of preparing burden like this, batching dry after 48 hours through ball milling again, behind the granulating and forming by as the sintering curre sintering of Fig. 1: (1). be warmed up to 800 ℃ of maintenances 40 minutes by room temperature (25 ℃) to arrange sticking speed (25 ℃------→ 500 ℃------→ 800 ℃).(2). be warmed up to 1150 ℃ with 300 ℃ speed per hour and kept 40 minutes.(3). be warmed up to 1295-1300 ℃ with 300 ℃ speed per hour and kept 70-90 minute.(4). cool to 1000 ℃ with 250-300 ℃ speed per hour, close stove and naturally cool to below 200 ℃ and comes out of the stove, sintering goes out the PTC ceramics.
Subordinate list: the present invention and sample test comparison sheet
Sample Nominal resistance R25 ℃ (Ω) Curie point ℃ Temperature coefficient %/℃ Voltage endurance (mA) Flowing special 220V3A impacts
???50V ??100V ??150V ??220V ??250V ??300V ??350V ??400V
Sample of the present invention ????18 ????87 ????10.8 ??17.5 ??11.6 ??8.5 ??6.2 ??5.1 ??5.0 ??4.8 ??4.5 Do not become more than 20 times
Comparative sample ????18.5 ????90 ????11.7 ??20.5 ??11.3 ??9 ??7.3 ??7.0 ??7.0 ??7.5 20 resistance value risings/several
Sample of the present invention ????15.1 ????90 ????15.3 ??19.8 ??12 ??9 ??7 ??6.5 ??6.0 ??5.5 ??5 30 times resistance value does not become
Comparative sample ????15.3 ????90 ????8.9 ??22.5 ??12.5 ??10 ??8.5 ??8.3 ??8.5 Resistance value increases 5 Ω after 8 times
Sample of the present invention ????12 ????90 ????13.6 ??22 ??13 ??9.0 ??8 ??7.5 ??7.0 ??6.5 20 times resistance value does not become
Comparative sample ????13 ????90 ????8.8 ??23.5 ??18.9 ??120V ??18.9 ??150V

Claims (6)

1.一种正温度系数陶瓷热敏电阻的制造方法，由钛酸钡(BaTiO3)、碳酸锶(SrCO3)、氧化铅(PbO)和二氧化钛(TiO2)等陶瓷材料构成，通过加入施主添加物(Sb)或铌(Nb)等微量稀土元素和改性添加物三氧化二铝(Al2O3)、氧化硅(SiO2)、二氧化锰(MnO2)等，通常采用两次配料法，第一次配料；在陶瓷材料钛酸钡(BaTiO3)中加入施主添加物的微量元素使其半导体化，加入钛酸锶(SrTiO3)取代部分钛酸钡(BaTiO3)以调节陶瓷材料的居理温度，加入钛酸钙(CaTiO3)改善陶瓷的物化特性，第二次配料：是在第一次配料基础上加入钛酸铅(PbTiO3)、二氧化锰(MnO2)、氧化铝(AlO3)、二氧化硅(SiO2)、二氧化钛(TiO2)、碳酸锂(Li-CO3)，在1350℃的温度下焙烧，其特征在于：在所述的第一次配料中还要加入二氧化锰(MnO2)；所述的施主添加物为双施主锑(Sb)及铌(Nb)；且用碳酸锶(Sr-CO3)取代部分碳酸钡(BaCO3)。1. A method for manufacturing a positive temperature coefficient ceramic thermistor, consisting of ceramic materials such as barium titanate (BaTiO 3 ), strontium carbonate (SrCO 3 ), lead oxide (PbO) and titanium dioxide (TiO 2 ), by adding donor Trace rare earth elements such as additives (Sb) or niobium (Nb) and modified additives such as aluminum oxide (Al 2 O 3 ), silicon oxide (SiO 2 ), manganese dioxide (MnO 2 ), etc., are usually used twice Batching method, the first batching; add trace elements of donor additives to the ceramic material barium titanate (BaTiO 3 ) to make it semiconducting, and add strontium titanate (SrTiO 3 ) to replace part of the barium titanate (BaTiO 3 ) to adjust Curie temperature of ceramic materials, adding calcium titanate (CaTiO 3 ) to improve the physical and chemical properties of ceramics, the second batching: adding lead titanate (PbTiO 3 ) and manganese dioxide (MnO 2 ) on the basis of the first batching , aluminum oxide (AlO 3 ), silicon dioxide (SiO 2 ), titanium dioxide (TiO 2 ), lithium carbonate (Li-CO 3 ), roasted at a temperature of 1350°C, characterized in that: in the first Manganese dioxide (MnO 2 ) is also added to the ingredients; the donor additives are double donors antimony (Sb) and niobium (Nb); and strontium carbonate (Sr-CO 3 ) is used to replace part of barium carbonate (BaCO 3 ) . 2.根据权利要求1所述的一种正温度系数陶瓷热敏电阻的制造方法，其特征在于：所述的双施主锑(Sb)及铌(Nb)的添加量为Sb+Nb＝0.11％md。2. The manufacturing method of a positive temperature coefficient ceramic thermistor according to claim 1, characterized in that: the addition amount of said double donor antimony (Sb) and niobium (Nb) is Sb+Nb=0.11% md. 3.根据权利要求2所述的一种正温度系数陶瓷热敏电阻的制造方法，其特征在于：碳酸钙(CaCO3)的添加量为0.04-0.05mol。3. The manufacturing method of a positive temperature coefficient ceramic thermistor according to claim 2, characterized in that the amount of calcium carbonate (CaCO 3 ) added is 0.04-0.05 mol. 4.根据权利要求1所述的一种正温度系数陶瓷热敏电阻的制造方法，其特征在于：碳酸锶(SrCO3)的添加量为0.07-0.2mol4. The manufacturing method of a positive temperature coefficient ceramic thermistor according to claim 1, characterized in that: the addition amount of strontium carbonate (SrCO 3 ) is 0.07-0.2mol 5.根据权利要求1所述的一种正温度系数陶瓷热敏电阻的制造方法，其特征在于：所述的钛酸铅的添加量为5-8％wt，所述的氧化铝(AlO3)的添加量为0.2-0.25％wt，所述的氧化硅(SiO2)的添加量为0.3-0.4％wt，所述的碳酸锂(Li2CO3)的添加量为0.03-0.04％wt。5. the manufacture method of a kind of positive temperature coefficient ceramic thermistor according to claim 1 is characterized in that: the addition amount of described lead titanate is 5-8%wt, and described aluminum oxide (AlO 3 ) is 0.2-0.25%wt, the silicon oxide (SiO2) is 0.3-0.4%wt, and the lithium carbonate (Li 2 CO 3 ) is 0.03-0.04%wt. 6.根据权利要求1所述的一种正温度系数陶瓷热敏电阻的制造方法，其特征在于：所述的烧结过程为(1).由室温(25℃)以排粘速度(25℃————→500℃————→800℃)升温到800℃保持40分钟。(2).以每小时300℃的速度升温到1150℃保持40分钟。(3).以每小时300℃的速度升温到1295-1300℃保持70-90分钟。(4).以每小时250-300℃的速度降温到1000℃，关炉自然冷却至200℃以下出炉，烧结出PTC瓷片。6. A method for manufacturing a positive temperature coefficient ceramic thermistor according to claim 1, characterized in that: the sintering process is (1). From room temperature (25° C.) to a sticking speed (25° C.- ———→500°C ————→800°C) raise the temperature to 800°C and keep for 40 minutes. (2). Raise the temperature to 1150°C at a rate of 300°C per hour and keep for 40 minutes. (3). Raise the temperature to 1295-1300°C at a rate of 300°C per hour and keep for 70-90 minutes. (4). Cool down to 1000°C at a rate of 250-300°C per hour, turn off the furnace and cool naturally to below 200°C, and then sinter the PTC tiles.
CN95111649A 1995-06-02 1995-06-02 Manufacturing method of positive temperature coefficient ceramic thermistor Expired - Fee Related CN1052804C (en)

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CN101429020B (en) * 2008-11-26 2011-11-23 丹东国通电子元件有限公司 Method for producing positive temperature coefficient thermistor for surge suppressor
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Cited By (3)

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Publication number Priority date Publication date Assignee Title
CN101429020B (en) * 2008-11-26 2011-11-23 丹东国通电子元件有限公司 Method for producing positive temperature coefficient thermistor for surge suppressor
CN103172368A (en) * 2011-12-20 2013-06-26 比亚迪股份有限公司 PTC thermistor and its making method
CN103172368B (en) * 2011-12-20 2014-10-08 比亚迪股份有限公司 PTC thermistor and its making method

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