DE2637227C3 - NTC thermistors for high temperatures - Google Patents
NTC thermistors for high temperaturesInfo
- Publication number
- DE2637227C3 DE2637227C3 DE19762637227 DE2637227A DE2637227C3 DE 2637227 C3 DE2637227 C3 DE 2637227C3 DE 19762637227 DE19762637227 DE 19762637227 DE 2637227 A DE2637227 A DE 2637227A DE 2637227 C3 DE2637227 C3 DE 2637227C3
- Authority
- DE
- Germany
- Prior art keywords
- thermistors
- high temperatures
- oxide
- samarium
- ntc
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000000203 mixture Substances 0.000 claims description 7
- KZUNJOHGWZRPMI-UHFFFAOYSA-N samarium atom Chemical compound [Sm] KZUNJOHGWZRPMI-UHFFFAOYSA-N 0.000 claims description 7
- 229910052772 Samarium Inorganic materials 0.000 claims description 5
- 229910052761 rare earth metal Inorganic materials 0.000 claims description 3
- 150000002910 rare earth metals Chemical class 0.000 claims description 3
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 claims description 2
- 239000000292 calcium oxide Substances 0.000 claims description 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 2
- 229910001954 samarium oxide Inorganic materials 0.000 claims description 2
- 229910003451 terbium oxide Inorganic materials 0.000 claims description 2
- SCRZPWWVSXWCMC-UHFFFAOYSA-N terbium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[Tb+3].[Tb+3] SCRZPWWVSXWCMC-UHFFFAOYSA-N 0.000 claims description 2
- 230000000694 effects Effects 0.000 description 4
- 239000011521 glass Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 3
- 230000010287 polarization Effects 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 238000009529 body temperature measurement Methods 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910001260 Pt alloy Inorganic materials 0.000 description 1
- 229910052771 Terbium Inorganic materials 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000001784 detoxification Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000005518 electrochemistry Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- JXSUUUWRUITOQZ-UHFFFAOYSA-N oxygen(2-);yttrium(3+);zirconium(4+) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[Y+3].[Y+3].[Zr+4].[Zr+4] JXSUUUWRUITOQZ-UHFFFAOYSA-N 0.000 description 1
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 1
- PUDIUYLPXJFUGB-UHFFFAOYSA-N praseodymium atom Chemical compound [Pr] PUDIUYLPXJFUGB-UHFFFAOYSA-N 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- GZCRRIHWUXGPOV-UHFFFAOYSA-N terbium atom Chemical compound [Tb] GZCRRIHWUXGPOV-UHFFFAOYSA-N 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910001928 zirconium oxide Inorganic materials 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
- H01C7/04—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material having negative temperature coefficient
- H01C7/042—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material having negative temperature coefficient mainly consisting of inorganic non-metallic substances
- H01C7/043—Oxides or oxidic compounds
Landscapes
- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Thermistors And Varistors (AREA)
Description
Die Erfindung betrifft einen Heißleiter für hohe Temperaturen, der aus einem gesinterten Oxidgemisch von Seltenerdmetallen bestehtThe invention relates to a thermistor for high temperatures made from a sintered oxide mixture consists of rare earth metals
Heißleiter im Sinne der Erfindung sind solche elektrischen Widerstände, die einen negativen Temperaturkoeffizienten ihrer Widerstandswerte aufweisen. Heißleiter sind auch unter der Bezeichnung Thermistor oder NTC-Widerstand bekannt Sie bestehen im allgemeinen aus Mischoxiden der Elemente Mangan, Eisen, Kobalt, Nickel, Kupfer bzw. Zink. Diese Oxide bzw. ihre Mischungen zersetzen sich allerdings bei Temperaturen oberhalb von 600° C, wobei irreversible Änderungen aber bereits schon bei niedrigeren Temperaturen auftreten, so daß Oxid-Heißleiter aus diesen Grundstoffen nur bei Temperaturen von höchstens 300 bis 350°C eingesetzt werden können.Thermistors within the meaning of the invention are electrical resistances that have a negative temperature coefficient their resistance values. NTC thermistors are also known as thermistors or NTC resistance known They generally consist of mixed oxides of the elements manganese, Iron, cobalt, nickel, copper or zinc. However, these oxides or their mixtures decompose Temperatures above 600 ° C, with irreversible changes already at lower Temperatures occur, so that oxide thermistors from these basic materials only at temperatures of a maximum of 300 to 350 ° C can be used.
Zur Messung und Regelung von Temperaturen im Bereich von 300 bis HOO0C wurden bisher entweder Pyrometer oder Metallwiderstände oder Thermoelemente verwendet. Pyrometer zeichnen sich allerdings durch eine relativ ungenaue Temperaturmessung aus, wobei eine Temperaturregelung mit ihnen praktisch unmöglich ist. Metallwiderstände haben eicen kleinen Temperaturkoeffizienten ihrer Widerstandswerte; deswegen benötigt man bei ihrer Anwendung im allgemeinen Verstärker. Thermoelemente für hohe Temperaturen können schließlich nur aus den — teuren — Platinmetallen angefertigt werden.To measure and control temperatures in the range from 300 to HOO 0 C, either pyrometers or metal resistors or thermocouples have been used so far. Pyrometers are, however, characterized by a relatively imprecise temperature measurement, and temperature control with them is practically impossible. Metal resistors have a small temperature coefficient of resistance; therefore, amplifiers are generally required in their application. After all, thermocouples for high temperatures can only be made from the - expensive - platinum metals.
Diese Aufgabe wird bei einem Heißleiter der eingangs angegebenen Art erfindungsgemäß dadurch gelöst, daß er aus Samarium- und Terbiumoxid besteht.This object is achieved according to the invention in the case of a thermistor of the type specified at the outset solved that it consists of samarium and terbium oxide.
Es sind zwar auch Heißleiter für hohe Temperaturen bekannt, die aus einer Seltenen Erde unter Zusatz von Zirkon-Oxid hergestellt sind. Insbesondere sind solche aus Yttrium-Zirkon-Oxid (GB-PS 8 74 882) und Praseo dym-Zirkon-Oxid (DT-OS 23 33 189) bekannt. Diese Heißleiter haben jedoch einen Varistor-Effekt, d. h. ihre Widerstandswerte sind nicht nur temperatur- sondern auch spannungsabhängig.Although there are also known thermistors for high temperatures, which are made from a rare earth with the addition of Zirconia are made. In particular, those made from yttrium zirconium oxide (GB-PS 8 74 882) and Praseo dym zirconium oxide (DT-OS 23 33 189) known. However, these thermistors have a varistor effect; H. their Resistance values are not only dependent on temperature but also on voltage.
Weiterhin ist in der »Zeitschrift für Elektrochemie« 1959, S. 269 bis 274, eine Untersuchung über die Leitfähigkeit der Seltenen Erden erschienen, ohne daß dort jedoch ein Hinweis darauf enthalten ist, daß Seltene Erden oder Mischungen aus ihnen als Heißleiter geeignet sind.Furthermore, in the "Zeitschrift für Elektrochemie" 1959, pp. 269 to 274, an investigation into the Conductivity of the rare earths appeared, but without there being any indication that Rare earths or mixtures of them are suitable as thermistors.
Die bisher bekannten Heißleiter für hohe Temperaturen sind also entweder zu hochohmig, haben zu geringe Temperaturkoeffizienten ihrer Widerstandswerte oder weisen Varistor-Effekte bzw. Polarisationserscheinungen auf.The previously known NTC thermistors for high temperatures are either too high or have too low a resistance Temperature coefficients of their resistance values or have varistor effects or polarization phenomena on.
Aufgabe der vorliegenden Erfindung ist es, einen Heißleiter anzugeben, der zur Messung und Regelung hoher Temperaturen geeignet ist, und der insbesondere einen großen Temperaturkoeffizienten seiner Widerstandswerte bei einem möglichst niedrigen spezifischen s Widerstand besitzt, und der andererseits auch keine Varistor-Effekte und Polarisationserscheinungen aufweist The object of the present invention is to specify a thermistor that is used for measurement and control is suitable for high temperatures, and in particular has a large temperature coefficient of its resistance values at the lowest possible specific resistance, and on the other hand also none Has varistor effects and polarization phenomena
Gemäß einer Weiterbildung der Erfindung enthält der Heißleiter 10 bis 90 Atom % Samarium.According to a further development of the invention, the thermistor contains 10 to 90 atom% samarium.
ίο Der erfindungsgemäße Heißleiter zeichnet sich dadurch aus, daß er bei einem niedrigen spezifischen Widerstand einen relativ hohen Temperaturkoeffizienten seiner Widerstandswerte aufweist Ferner hat er keinen Varistor-Effekt und auch beim Anlegen einer Meßspannung zeigen sich keine Polarsationserscheinungen. Da die Seltenen Erden eine sehr hohe Bildungsenthalpie besitzen, wodurch sie sich bei Temperaturen bis zu mindestens 17500C nicht zersetzen, läßt sich der erfindungsgemäße Heißleiter zur Messung und Regelung sehr hoher Temperaturen einsetzen.The thermistor according to the invention is characterized in that, with a low specific resistance, it has a relatively high temperature coefficient of its resistance values. Furthermore, it has no varistor effect and there are no signs of polarization when a measuring voltage is applied. Since the rare earths have a very high enthalpy of formation, as a result of which they do not decompose at temperatures up to at least 1750 ° C., the thermistor according to the invention can be used for measuring and regulating very high temperatures.
Weiterhin können die erfindungsgemäßen Heißleiter zusätzlich bis zu zwei Gew.% Kalziumoxid als
Mineralisator enthalten, ohne daß sich ihre elektrischen Werte bzw. Eigenschaften wesentlich ändern.
Ausführungsbeispiel 1:Furthermore, the thermistors according to the invention can additionally contain up to two% by weight of calcium oxide as a mineralizer without their electrical values or properties changing significantly.
Embodiment 1:
Ein Gemisch aus Samarium (Reinheit 99,9%)- und Terbium (Reinheit 99,9%) -Oxid, das 40 Atom % Samarium enthält, wird in Salzsäure aufgelöst und gemeinsam als Oxalat ausgefüllt. Das gefällte Oxalat wird abfiltriert, bei einer Temperatur von 9000C kalziniert und anschließend fein gemahlen. Zur Herstellung von Thermistoren wird das kalzinierte und gemahlene Oxidgemisch mit einem geeigneten Bindemittel versehen und als Perle zwischen zwei parallel gespannten Drähten aus Platin oder einer Platinlegierung angebracht. Nach einer Vortrocknung wird die Thermisterperle bei Temperaturen von 1550 bis 17000C in oxidierender Atmosphäre gesintert. Je nach ge-A mixture of samarium (purity 99.9%) and terbium (purity 99.9%) oxide, which contains 40 atom% samarium, is dissolved in hydrochloric acid and filled together as oxalate. The precipitated oxalate is filtered off, calcined at a temperature of 900 ° C. and then finely ground. For the production of thermistors, the calcined and ground oxide mixture is provided with a suitable binding agent and attached as a pearl between two parallel tensioned wires made of platinum or a platinum alloy. After pre-drying, the Thermister bead is sintered at temperatures of 1550 to 1700 ° C. in an oxidizing atmosphere. Depending on the
•»o wünschtem Anwendungsgebiet kann die gesinterte
Perle mit einem Glasüberzug versehen oder in ein Glas-, Quarz-, Aluminiumoxid- oder ähnliches Gehäuse eingebaut
werden. Dies empfiehlt sich besonders, wenn der Heißleiter zur Temperaturmessung bzw. -regelung
agressiver Medien verwendet werden soll.
Ausführungsbeispiel 2:• O the desired area of application, the sintered pearl can be provided with a glass coating or built into a glass, quartz, aluminum oxide or similar housing. This is particularly recommended if the NTC thermistor is to be used to measure or control the temperature of aggressive media.
Embodiment 2:
Thermistoren werden in gleicher Weise wie im Ausführungsbeispiel 1 hergestellt, wobei das Ausgangsgemisch 60 Atom % Samarium enthält.Thermistors are manufactured in the same way as in embodiment 1, with the starting mixture Contains 60 atom% samarium.
so In der Figur ist der spezifische Widerstand Rspcz der nach den Ausführungsbeispielen hergestellten Heißleiter in Abhängigkeit von der Temperatur f dargestellt. Wie den Kennlinien zu entnehmen ist, ändern sich die Widerstandswerte des erfindungsgemäßen Heißleiters im gesamten Temperaturbereich stetig.so In the figure, the specific resistance R spcz of the thermistors manufactured according to the exemplary embodiments is shown as a function of the temperature f. As can be seen from the characteristic curves, the resistance values of the thermistor according to the invention change continuously over the entire temperature range.
Der erfindungsgemäße Heißleiter eignet sich allgemein zur Temperaturmessung und -regelung für Temperaturen oberhalb von 2000C. Als besondere Anwendungsgebiete seien die Abgasentgiftung in derThe thermistor according to the invention is generally suitable for temperature measurement and control for temperatures above 200 ° C. As special areas of application, exhaust gas detoxification in the
so Kraftfahrzeug-Industrie, Schmelzofen in der Glas-Industrie, Backöfen bei Haushaltsgeräten und die Metallurgie in der chemischen Industrie genannt.so automotive industry, melting furnace in the glass industry, Ovens in household appliances and metallurgy in the chemical industry.
Her erfindungsgemäße Heißleiter läßt sich nicht nur in der in den Ausführungsbeispielen beschriebenenHer thermistor according to the invention can not only be described in the exemplary embodiments
b5 Perlenform, sondern auch in den anderen bekannten Formen wie z. B. Scheiben, Stäbe oder Röhrchen herstellen.b5 pearl shape, but also known in the other Forms such as B. produce discs, rods or tubes.
Hierzu 1 Blatt Zeichnungen1 sheet of drawings
Claims (3)
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19762637227 DE2637227C3 (en) | 1976-08-18 | 1976-08-18 | NTC thermistors for high temperatures |
| GB20103/77A GB1518487A (en) | 1976-08-18 | 1977-05-13 | Hot conductors |
| FR7724034A FR2362478B3 (en) | 1976-08-18 | 1977-08-04 | THERMISTOR FOR HIGH TEMPERATURES |
| IT26514/77A IT1085734B (en) | 1976-08-18 | 1977-08-05 | HIGH TEMPERATURE THERMISTOR |
| US05/822,196 US4126583A (en) | 1976-08-18 | 1977-08-05 | High temperature thermistors (NTC) |
| JP9907077A JPS5324598A (en) | 1976-08-18 | 1977-08-18 | Negative thermistor for high temperature |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19762637227 DE2637227C3 (en) | 1976-08-18 | 1976-08-18 | NTC thermistors for high temperatures |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| DE2637227A1 DE2637227A1 (en) | 1978-02-23 |
| DE2637227B2 DE2637227B2 (en) | 1978-06-08 |
| DE2637227C3 true DE2637227C3 (en) | 1979-02-08 |
Family
ID=5985766
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE19762637227 Expired DE2637227C3 (en) | 1976-08-18 | 1976-08-18 | NTC thermistors for high temperatures |
Country Status (1)
| Country | Link |
|---|---|
| DE (1) | DE2637227C3 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3125474A1 (en) * | 1981-06-29 | 1983-01-20 | Siemens AG, 1000 Berlin und 8000 München | Process for fabricating an NTC thermistor for controlling and measuring temperatures over a wide temperature range |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE68927319T2 (en) * | 1988-10-19 | 1997-04-03 | Gen Electric | Polycrystalline neutron-absorbing sintered bodies which contain rare earth oxides and those sintered bodies which are stabilized against water with a group 4A metal oxide. |
| CN110942874A (en) * | 2019-12-04 | 2020-03-31 | 句容市博远电子有限公司 | Thermistor added with calcium oxide and preparation method thereof |
-
1976
- 1976-08-18 DE DE19762637227 patent/DE2637227C3/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3125474A1 (en) * | 1981-06-29 | 1983-01-20 | Siemens AG, 1000 Berlin und 8000 München | Process for fabricating an NTC thermistor for controlling and measuring temperatures over a wide temperature range |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2637227A1 (en) | 1978-02-23 |
| DE2637227B2 (en) | 1978-06-08 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| OAP | Request for examination filed | ||
| OD | Request for examination | ||
| C3 | Grant after two publication steps (3rd publication) | ||
| 8320 | Willingness to grant licences declared (paragraph 23) | ||
| 8339 | Ceased/non-payment of the annual fee |