CN101445365A - Barium titanate-based positive temperature coefficient resistance material and preparation method thereof - Google Patents
Barium titanate-based positive temperature coefficient resistance material and preparation method thereof Download PDFInfo
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- CN101445365A CN101445365A CNA2008102204953A CN200810220495A CN101445365A CN 101445365 A CN101445365 A CN 101445365A CN A2008102204953 A CNA2008102204953 A CN A2008102204953A CN 200810220495 A CN200810220495 A CN 200810220495A CN 101445365 A CN101445365 A CN 101445365A
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Abstract
The invention discloses a barium titanate-based positive temperature coefficient resistance material and a preparation method thereof. The chemical general formula of the barium titanate-based positive temperature coefficient resistance material is (1-x-y)BaTiO3-x(Bi0.5Na0.5)TiO3-y(Bi0.5K0.5)TiO3+z mol% MO, wherein, x is not less than 0 but not more than 0.30, y is not less than 0 but not more than 0.40, and z is not less than 0 but not more than 2, and MO is metal oxide. A sol-gel method, a solid phase reaction method and a spark plasma sintering method are applied to preparing the resistance material. The resistance material does not contain lead, which avoids environmental pollution and personal injury which are caused by volatilization of the lead during the manufacture and the use. The resistance material has the advantages of simple process and low cost, and is applicable to large-scale industrialized production and application of piezoelectronic devices.
Description
Technical field
It is ceramic field that invention belongs to barium titanate (BT), is specifically related to a kind of barium titanate-based positive temperature coefficient resistance material and preparation method thereof.
Background technology
In recent years, along with the demand of environment protection and human social, research and development novel environmental close friend's lead-free high-temperature positive temperature coefficient (PTC) resistive material has become one of focus material that world developed country endeavours to research and develop.PTC resistance product divides from function, and application such as overcurrent protection, demagnetization, electric motor starting, thermostatically heating are arranged, and derived product such as programme-controlled exchange, refrigerator, air-conditioning, automobile, lighting etc. all are main application fields.As PTC standard heating member, porous ptc heater, cosmetology warm-air drier, kettle insulation ptc heater, babymilk thermos cup, airheater, air-conditioning electrical auxiliary heater, moisture-proof insulation airheater.
PTC has temperature automatically controlled effect, can integrate temperature control and generate heat.Have temperature sensing, overcurrent protection function, it is from recovery, long lifetime, simple in structure, energy saving, the flames of anger, a series of outstanding advantages such as safe and reliable and enjoy favor.Be widely used in industry and consumer electronic device and household appliance technical field such as electronic communication, aerospace, automotive industry, household electrical appliance.
Present unleaded PTC material mainly contains macromolecular material, but the high molecular PTC material at high temperature is softening, has limited its range of application.And the positive temperature coefficient transition temperature that improves barium titanate both at home and abroad mainly is to realize by adding lead element, though this kind method and technology is ripe and obtained effect preferably, plumbous have very strong toxicity.All there is very strong harm in lead-containing materials to recycling use again from being prepared into use.Plumbous harm to the mankind particularly influence of the children's health below six years old has reached very serious stage.Along with the needs of environment protection and Sustainable development, having begun in 2006 in the world to completely forbid to use has plumbous piezo component, therefore develops unleaded high-curie temperature positive temperature coefficient ceramic tool and has very important significance.There are a lot of Chinese invention patents to report the preparation method of environment-friendly type PTC material, as macromolecular material; Belong to the barium titanate-based positive temperature coefficient pottery of oxide compound as gold doping, but Curie temperature not high (being lower than 130 ℃); Relevant unleaded positive temperature coefficient barium titanate series resistor ceramic with high-curie temperature does not still have patent report at present.With barium carbonate, bismuthous oxide bismuth trioxide, salt of wormwood, yellow soda ash, titanium dioxide, Manganse Dioxide etc. is raw material, can prepare barium titanate ceramics with traditional solid phase reaction method with high-curie temperature, method is simple, cost is low, is suitable for the application of large-scale industrialization production and piezo component.
Summary of the invention
The object of the invention is to provide a kind of barium titanate-based positive temperature coefficient resistance material and preparation method thereof, particularly in the configuration of barium titanate doping ratio, mixes sodium, mixes potassium, mixes the difference of bismuth ratio, can obtain different Curie temperature.The Curie temperature of the back barium titanate that mixes is all increased.
A kind of barium titanate-based positive temperature coefficient resistance material provided by the invention, chemical general formula is:
(1-x-y) BaTiO
3-x (Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO, wherein 0≤x≤0.30,0≤y≤0.40 and 0≤z≤2, wherein MO is metal oxide such as manganese oxide Mn
2O or MnO
2, niobium oxides Nb
2O
3, weisspiessglanz Sb
2O
3Or titanium oxide TiO
2
Described metal oxide is one or more in manganese oxide, niobium oxides, weisspiessglanz, the titanium oxide.
Barium titanate-based positive temperature coefficient resistance material preparation method provided by the invention uses collosol-gelling process, solid reaction process, discharge plasma sintering method to prepare barium titanate-based positive temperature coefficient resistance material.
Synthetic with solid reaction process, be raw material at first with barium carbonate, bismuthous oxide bismuth trioxide, yellow soda ash, titanium dioxide, carry out the weighing proportioning by barium titanate and bismuth-sodium titanate prescription, batch mixing, pulverize with planetary mills, oven dry, through 950 ℃ of pre-burnings 2 hours, pulverize, add glue, compressing tablet, be incubated one minute with planetary mills again through 1340 ℃, be cooled to 2 hours sintering processings of 1260 ℃ of insulations rapidly with the speed of 30～50 ℃/min again and carry out sintering, again the sample that sinters is carried out abrasive disc, by electrode to performance test.
Barium titanate-based positive temperature coefficient resistance material provided by the invention has following advantage: composition is unleaded, avoided material make and use in plumbous volatilization and cause the pollution to environment, the injury of human body.Just can improve the Curie temperature of material by a spot of doping, solve the difficult problem of barium titanate series low curie point temperature.Its Curie temperature of unleaded barium titanate-bismuth-sodium titanate (0.90BT-0.10BNT) function ceramics with this resistive material preparation can reach 184 ℃ high-curie temperature, positive temperature coefficient ceramic resistance.Barium titanate-bismuth potassium titanate of mixing niobium (0.99BT-0.01BKT-Nb) pottery with this resistive material preparation has excellent positive temperature coefficient (PTC) electricresistance effect.The inventive method is simple, cost is low, is suitable for the application of large-scale industrialization production and piezo component.
Description of drawings
Fig. 1 is that barium titanate-bismuth-sodium titanate of the present invention (the two mol ratio 0.94/0.06) is the XRD spectrum of pottery, and calcined temperature is 950 ℃, and last sintering temperature is 1260 ℃, is polycrystalline ceramics.
Fig. 2 is the dielectric temperature spectrogram of barium titanate provided by the invention-bismuth-sodium titanate pottery.
Wherein X-coordinate is a temperature, and unit is ℃ that ordinate zou is a specific inductivity.The Curie temperature of barium titanate-bismuth-sodium titanate pottery (the two mol ratio 0.94/0.06) is 163 ℃ as can be seen from the figure, is under the 10kHz situation in 25 ℃ of frequencies of room temperature, and its specific inductivity is 687.
Fig. 3 is resistivity-temperature (curve of ρ-T) of barium titanate-bismuth-sodium titanate provided by the invention (the two mol ratio 0.90/0.10).
Wherein X-coordinate is a temperature, and unit is ℃; Ordinate zou is resistivity (ρ), and unit is Ω cm.
Embodiment
Further illustrate substantive distinguishing features of the present invention and significant advantage below by embodiment, the present invention only is confined to described embodiment by no means.
Embodiment 1
Change barium titanate-bismuth-sodium titanate-bismuth potassium titanate+metal oxide [(1-x-y) BaTiO
3-x (Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO] proportioning, as x=0.06, y=0.0, z=0.With the synthetic mole of traditional solid reaction process proportioning be: the pottery of barium titanate: bismuth-sodium titanate: bismuth potassium titanate=0.94:0.06:0.0.Be raw material at first with barium carbonate, bismuthous oxide bismuth trioxide, yellow soda ash, titanium dioxide, carry out the weighing proportioning by barium titanate and bismuth-sodium titanate prescription, batch mixing, pulverize with planetary mills, oven dry, through 950 ℃ of pre-burnings 2 hours, again with planetary mills pulverize, add glue, compressing tablet, through 1340 ℃ of insulations one minute, be cooled to 2 hours sintering processings of 1260 ℃ of insulations rapidly with the speed of 30 ℃/min again and carry out sintering, again the sample that sinters is carried out abrasive disc, by electrode to performance test.X-ray diffraction is measured its structure, and the result shows, this special annealing way burns the pottery that, for the preferred orientation growth, in useful range, has only two diffraction peaks, and wherein (111) diffraction peak is the strongest, is (002) secondly, single crystal-like, as shown in Figure 1.And anneal with traditional mode, be the polycrystalline sample.Dielectric temperature spectrum result shows the Curie temperature of sample, i.e. T
c=163 ℃.Its dielectric temperature collection of illustrative plates as shown in Figure 2.
Embodiment 2
Be to change barium titanate-bismuth-sodium titanate-bismuth potassium titanate+metal oxide [(1-x-y) BaTiO
3-x (Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO] proportioning, as x=0.10, y=0.0, z=0.With the synthetic mole of traditional solid reaction process proportioning be: the pottery of barium titanate: bismuth-sodium titanate: bismuth potassium titanate=0.90:0.10:0.0.Be raw material at first with barium carbonate, bismuthous oxide bismuth trioxide, yellow soda ash, titanium dioxide, carry out the weighing proportioning by barium titanate, bismuth-sodium titanate and bismuth potassium titanate prescription, batch mixing, pulverize with planetary mills, oven dry, through 950 ℃ of pre-burnings 2 hours, again with planetary mills pulverize, add glue, compressing tablet, through 1340 ℃ of insulations one minute, be cooled to 2 hours sintering processings of 1260 ℃ of insulations rapidly with the speed of 40 ℃/min again and carry out sintering, again the sample that sinters is carried out abrasive disc, by electrode to performance test.Measure its structure, be the polycrystalline uhligite.Curie temperature, T
c184 ℃ of ≈.Room temperature annex (25 ℃), resistivity are 12 Ω cm; Liftdrag (maximum resistance rate/lowest resistivity) is greater than 10
4, temperature factor (α) is 6.9%/℃, have good positive temperature coefficient (PTC) effect, see Fig. 3.
Embodiment 3
Change barium titanate-bismuth-sodium titanate-bismuth potassium titanate+metal oxide [(1-x-y) BaTiO
3-x (Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO] proportioning, as x=0, y=0.01, z=0.025 get niobium oxides (Nb
2O
5).Elder generation is synthesis of barium titanate, bismuth-sodium titanate and bismuth potassium titanate respectively.Be raw material at first promptly with barium carbonate, bismuthous oxide bismuth trioxide, salt of wormwood, titanium dioxide etc., carry out the weighing proportioning by barium titanate and bismuth potassium titanate different ingredients, batch mixing, pulverize oven dry with planetary mills, through 950 ℃ of pre-burnings 2 hours, distinguish synthesis of barium titanate and bismuth potassium titanate powder respectively.Again according to barium titanate: bismuth-sodium titanate: bismuth potassium titanate: niobium oxides=0.90:0.0:0.01:0.00025 mole proportioning, pulverize, add glue, compressing tablet, be incubated one minute with planetary mills through 1340 ℃, be cooled to 2 hours sintering processings of 1260 ℃ of insulations rapidly with the speed of 50 ℃/min again and carry out sintering, again the sample that sinters is carried out abrasive disc, by electrode to performance test.Measure its Curie temperature, T
c148 ℃ of ≈.Room temperature resistance resistivity is 12 Ω cm; Liftdrag (maximum resistance rate/lowest resistivity) is greater than 8 * 10
3, temperature factor (α) be greater than 18%/℃, have excellent positive temperature coefficient (PTC) effect.
Embodiment 4
Change barium titanate-bismuth-sodium titanate-bismuth potassium titanate+metal oxide [(1-x-y) BaTiO
3-x (Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO] proportioning, as x=0, y=0.20, z=0.0.With traditional solid reaction process synthesis of barium titanate-bismuth potassium titanate (0.80BT-0.20BKT) pottery.All the other are with embodiment 1.The Curie temperature that obtains, T
c=210 ℃.
Embodiment 5
Change barium titanate-bismuth-sodium titanate-bismuth potassium titanate+metal oxide [(1-x-y) BaTiO
3-x (Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO] proportioning, as x=0, y=0.30, z=0.0.With traditional solid reaction process synthesis of barium titanate-bismuth potassium titanate (0.70BT-0.30BKT) pottery.All the other are with embodiment 1.The ceramics sample Curie temperature that obtains, T
c=240 ℃.The ceramics sample that promptly has high-curie temperature and positive temperature coefficient (PTC).
Embodiment 6
Change barium titanate-bismuth-sodium titanate-bismuth potassium titanate+metal oxide [(1-x-y) BaTiO
3-x (Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO] proportioning, as x=0.20, y=0, z=0.With traditional solid reaction process synthesis of barium titanate-bismuth-sodium titanate (0.80BT-0.20BNT) pottery.All the other are with embodiment 1.The Curie temperature that obtains, T
c=210 ℃.
Embodiment 7
Change barium titanate-bismuth-sodium titanate-bismuth potassium titanate+metal oxide [(1-x-y) BaTiO
3-x (Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO] proportioning, as x=0.10, y=0.0, z=0.05 gets manganese oxide.With traditional solid reaction process synthesis of barium titanate-bismuth-sodium titanate-metal oxide (0.98BT-0.10BNT+0.05mol%MnO
2) pottery.All the other are with embodiment 1.The sample Curie temperature that obtains, T
c=190 ℃.
Claims (4)
1. barium titanate-based positive temperature coefficient resistance material, chemical general formula is:
(1-x-y) BaTiO
3-x(Bi
0.5Na
0.5) TiO
3-y (Bi
0.5K
0.5) TiO
3+ z mol%MO, wherein 0≤x≤0.30,0≤y≤0.40 and 0≤z≤2, wherein MO is a metal oxide.
2. resistive material according to claim 1 is characterized in that: described metal oxide is one or more in manganese oxide, niobium oxides, weisspiessglanz, the titanium oxide.
3. the described barium titanate-based positive temperature coefficient resistance material preparation method of claim 1 uses collosol-gelling process, solid reaction process, discharge plasma sintering method to prepare barium titanate-based positive temperature coefficient resistance material.
4. the preparation method of barium titanate-based negative temperature coefficient resistance material according to claim 3, it is characterized in that: synthetic with solid reaction process, at first with barium carbonate, bismuthous oxide bismuth trioxide, yellow soda ash, titanium dioxide is raw material, through the weighing proportioning, batch mixing, pulverize with planetary mills, oven dry, through 950 ℃ of pre-burnings 2 hours, pulverize with planetary mills again, add glue, compressing tablet, through 1340 ℃ of insulations one minute, be cooled to 2 hours sintering processings of 1260 ℃ of insulations rapidly with the speed of 30～50 ℃/min again and carry out sintering, again the sample that sinters is carried out abrasive disc, by electrode to performance test.
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| CN102976747A (en) * | 2012-12-04 | 2013-03-20 | 广西新未来信息产业股份有限公司 | Lithium niobate doped barium titanate based positive temperature coefficient resistance material and preparation method thereof |
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| CN103172370A (en) * | 2011-06-16 | 2013-06-26 | 桂林电子科技大学 | Lead-free piezoelectric ceramic consisting of B-bit compound Bi-based compounds and preparation method thereof |
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| CN103086712A (en) * | 2012-12-14 | 2013-05-08 | 广西新未来信息产业股份有限公司 | Bi2WO6-modified barium titanate-based lead-free positive temperature coefficient resistance material and preparation method thereof |
| CN103964839A (en) * | 2013-01-30 | 2014-08-06 | 比亚迪股份有限公司 | Positive temperature coefficient thermistor material and its preparation method |
| CN103964839B (en) * | 2013-01-30 | 2015-12-02 | 比亚迪股份有限公司 | A kind of posistor material and preparation method thereof |
| CN103553592A (en) * | 2013-11-01 | 2014-02-05 | 华北水利水电大学 | Modified barium titanate powder preparation method |
| CN103553592B (en) * | 2013-11-01 | 2015-11-18 | 华北水利水电大学 | A kind of modified barium carbonate raw powder's production technology |
| CN105254290A (en) * | 2015-09-28 | 2016-01-20 | 桂林理工大学 | High curie point positive temperature coefficient resistance material Ba2BiTiV3O13 and preparation method thereof |
| CN109761602A (en) * | 2019-02-28 | 2019-05-17 | 华中科技大学 | A kind of low-resistance thermal sensitive ceramic material and the preparation method and application thereof |
| CN109761602B (en) * | 2019-02-28 | 2020-11-24 | 华中科技大学 | Low-resistance thermal sensitive ceramic material and preparation method and application thereof |
| CN116332639A (en) * | 2022-12-08 | 2023-06-27 | 上海材料研究所有限公司 | Lead-free PTC thermal sensitive ceramic material with low room temperature resistivity and high lift-drag ratio and preparation method thereof |
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Open date: 20090603 |