CN103322800A - Fully transparent tube type resistance furnace - Google Patents
Fully transparent tube type resistance furnace Download PDFInfo
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- CN103322800A CN103322800A CN201210076605XA CN201210076605A CN103322800A CN 103322800 A CN103322800 A CN 103322800A CN 201210076605X A CN201210076605X A CN 201210076605XA CN 201210076605 A CN201210076605 A CN 201210076605A CN 103322800 A CN103322800 A CN 103322800A
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Abstract
The invention discloses a fully transparent tube type resistance furnace. The resistance furnace has the following characteristics: an outer casing and a heating pipe are made of transparent quartz tubes; the transparent structure is convenient for adding material, firing and observing, and can help shorten the period required by optimizing material preparation process window; a furnace chamber, namely a chamber between the outer casing and the heating pipe, adopts vacuum and serves as a heat insulating layer; not only is the cost greatly reduced, but also fast cooling can be realized when the furnace chamber is not under the vacuum state; a vacuum insulation layer reduces the oxidation of electric heating wires and ensures long-term stable running of the resistance furnace; the density of heating wires wrapped on the heating pipe directly determines the distribution of temperature zones, and the adjustment of temperature zones can be realized through the adjustment of the arrangement of the heating wires; a quartz liner tube is adopted to prevent the contamination of reactants to a heating inner tube and contamination between different materials, and different designs of the structure of the quartz liner tube can lead to different distribution situations of fluid field, so that material preparation becomes flexible and diversified.
Description
Technical field
The invention belongs to furnace equipment, be specifically related to a kind of all-transparent tube type resistance furnace.
Background technology
[0002] tube type resistance furnace is because the various advantages such as easy to operate, temperature is balanced, lifting temperature speed is fast, temperature control is accurate, energy consumption is low, (oxygen, nitrogen, argon gas, the hydrogen etc.) protection of can leading to multiple gases are widely used in the fields such as pottery, metallurgy, electronics, glass, chemical industry, machinery, refractory material, new material exploitation, special material, building materials.In recent years, tube type resistance furnace is more and more outstanding in the application of preparation new material and special material, especially has been subject to paying attention to widely aspect preparing at the one dimension micro-nano material.
Recent years, for the unusual physical property of understanding one dimension micro-nano material (nano wire, nanobelt, nanometer rods and nanotube etc.) and at the application potential of micro-nano photoelectric device, people are studied the one dimension micro-nano material, mainly concentrate in the material preparation.Wherein the tube type resistance furnace vapor phase method of taking as the leading factor is simple, the direct and the most important method that obtains one dimension micro-nano monocrystalline.Can control well diameter, length and the structure of one dimension micro-nano monocrystalline with this method.At present, the one dimension micro-nano material has a wide range of applications in fields such as optics, electronics, environment and medical science, for microminiaturization, the nanometer of device provides material foundation, has become the focus of present material area research.
In this field, the Yang Pei east research group in the Wang Zhonglin research group of the georgia ,u.s.a Institute of Technology and branch school, California, Berkeley University has successively reported their ground-breaking work, and (Science. 2001,291:1947-1949) (Science. 2001,292:1897-1899).(Science. 2001,291:1947-1949) utilize the VS method to successfully synthesize first ZnO, SnO in Wang Zhonglin research group
2, In
2O
3, Ga
2O
3, the wide bandgap semiconductor such as CdO single crystal nano-belt.Its detailed process is the temperature end that the material powder of these materials is placed on tube furnace, directly is heated to 1300-1500 ℃ and decomposes under the low pressure condition, then obtains the nanobelt of this material in low-temperature end.These nanometer bandwidth 30～300 nm, width is 5～l0 with the ratio of thickness, and length can extend to several millimeter, and purity is high, output is large, perfect structure, surface clean, and does not almost have defective in the body, is desirable monocrystalline line style flake structure.Yang Pei east research group (Adv. Mater. 2001,13,113 – 116) adopts VLS mechanism and vapor phase epitaxy technique to combine growing ZnO nano-wire array on sapphire substrates.They are at first in the Grown on Sapphire Substrates layer of Au film, then with the ZnO powder that mixes and graphite powder as raw material, put into the diamond heating district, under high-purity Ar is protected, mix powder is heated to 880 ~ 905 ℃.It is in the low temperature depositing district that the Zn of distillation is transported to nano wire " vitellarium " by Ar.Having placed in the vitellarium provides the process for sapphire-based of nanowire growth bottom material.ZnO can be in the district's epitaxial growth of Au film, because good coupling between the c face of substrate and ZnO, ZnO can be perpendicular to upwards growth of substrate, and finally obtaining diameter is 70 ~ 120nm, the ZnO nano-wire of long 2 ~ 10 μ m.After this, the research of one dimension micro-nano material begins develop rapidly, and relevant research report also continues to bring out.
The tube furnace vapor phase method can also be prepared multiple inorganic and organic micro-nano material, Si nano wire for example, IZO superlattices nanobelt, multiple one-dimensional inorganic nano material (D. P. Yu, Z. G. Bai, the Y. Ding such as GaN, IGZO nano wire, Q. L. Hang, H. Z. Zhang, J. J. Wang, etal Appl. Phys. Lett. 1998,3458 (72)), (J. S. Jie, G. Z. Wang, X. H. Han, and J.G. Hou; J. Phys. Chem. B 2004,17027 (108)), (X. F. Duan and C. M. Lieber, J. Am. Chem. Soc. 2000,298 (122)), (D. P. Li, G. Z. Wang, Q. H. Yang, and X. Xie, J. Phys. Chem. C 2009,21512 (113)), also can be for the preparation of CuPc, perfluor CuPc, three (oxine) aluminium, 2,4, organic nano material (the Tang Q. X. such as 5-triphenyl imidazoles; Li H. X.; He M.; Hu W.P.; Liu C. M.; Chen K. Q.; Wang C.; Liu Y. Q.; Zhu D. B.; ADV. MATER. 2006,65 (18) .), (Tang Q. X., Li H. X., Liu Y. L., Hu W. P., J. Am. Chem. Soc 2006,14634 (128) .), (Y. S. Zhao, Chong-an Di, W.S. Yang, Gui Yu, Y.Q. Liu, and J. N. Yao; Adv. Funct. Mater. 2006,1985 (16)), (Y. S. Zhao, D.B. Xiao, W. S. Yang, A. D. Peng and J. N. Yao, Chem. Mater. 2006,2302 (18)).
Yet in preparation one dimension micro-nano material preparation process, traditional tube furnace exposes some shortcomings.The one, because body of heater is opaque, can not observe at any time the situation in the stove.Therefore can only grope again and again condition, this has not only increased the difficulty of firing and has expended a lot of times and resource.The 2nd,, traditional tube furnace burner hearth often adopts the little materials such as ceramic fibre sheet material of thermal conductivity factor as heat insulation layer.Although this is favourable to when heating, when annealing, because it is slower to dispel the heat, relatively expend time in.The 3rd,, the cost of the heat insulation layer material that burner hearth adopts is higher.These problems make the development of one dimension micro-nano material preparation run into larger obstacle, have slowed down that device is microminiaturized, the step of nanometer future development.
Summary of the invention
The purpose of this invention is to provide a kind of all-transparent tube type resistance furnace.
Concrete structure of the present invention comprises inlet end, and body of heater and outlet side three parts form.Inlet end comprises flowmeter and needle-valve, and the regulation and control carrier gas enters.Body of heater comprises furnace body support, and suprasil shell and transparent heating tube find time to play vacuum as the effect of heat insulation layer by mechanical pump to cavity between suprasil shell and the transparent heating tube.Thermocouple is fixed in heating tube outside monitoring temperature, and a quartz liner is arranged in the transparent heating tube.The outlet side comprises vacuum meter, and flapper valve and bellows equal vacuum chain jointed tubular workpieces couple together several parts and the mechanical pump that need in the stove to find time.Inlet end, body of heater are connected the KF flange and connect with the outlet side, by these connector sampling blowings.
This transparent tubular type furnace structure has following characteristics:
1) shell and heating tube are made of transparent quartz tube.Transparent configuration makes things convenient for filling, fires, observes, and is conducive to shorten the required cycle of material preparation process window optimization.
2) burner hearth is to adopt vacuum as heat insulation layer between furnace shell and heating tube.This not only greatly reduces cost, and can realize fast cooling when being in antivacuum state in the chamber, and the oxidation that the vacuum insulation layer has slowed down heating wire has guaranteed the long-term stable operation of stove.
3) in the situation that be lower than 700 ℃ and only reduce convection heat transfer' heat-transfer by convection and heat by vacuum layer and conduct and get final product, under higher temperature, the heat that the heat radiation mode dissipates becomes increasing, at this moment can realize interception to radiant heat transfer by evaporation one deck infrared reflection film inside the shell.
4) distribution that the winding density degree of heater strip has directly determined the humidity province on the heating tube utilizes this characteristics, can realize easily the adjustment of humidity province by changing arranging of heater strip, so that stove possesses better adaptability to the preparation of different materials.
5) position of thermocouple generally is placed on the residing highest temperature zone of raw material, also can add as required the group number of temperature controlling instruments, realizes the temperature field is controlled more flexibly.
6) pointer vacuum meter has preferably response than electron vacuum gage to pressure near an atmospheric situation, and this has guaranteed that stove inside too high malleation can not occur, makes the safe handling of stove energy.
7) use of quartz liner can prevent that reactant to the pollution of heating inner tube and the pollution between different materials, designing different quartz liner structures and can obtain different Flow Field Distribution, and this is so that material preparation becomes more versatile and flexible.
The usage comparison of this tube furnace is flexible, and the use step below usually adopting in the preparation process of monodimension nanometer material can guarantee the operation that stove is safer:
1. according to physicochemical properties and the experiment needs of material, the resistance wire of setting tube furnace distributes, and adjusting temperature controller parameter to stove can steady operation.
2. material and substrate etc. is put into quartz liner inside, then push in the heating tube, adjusted position postpone connects the vacuum adapter coupling.
3. closing baffle plate valve and needle-valve are opened mechanical pump, and insulation chambers is found time, and slow regulating fender valve so that pressure slowly drops to is minimum, then passes into carrier gas to subscribing pressure.
4. close carrier gas and flapper valve, set temperature increasing schedule and begin heating, by the time after the reaction temperature of subscribing, controllable register valve and needle-valve are so that carrier gas flux and chamber internal gas pressure satisfy setting value.
5. after reaction is finished, close first carrier gas, flapper valve if need fast cooling, can cut out vavuum pump, and venting in the backward insulation chambers.
6. by the time temperature drops to enough lowly, open needle-valve, pass into carrier gas, wait until that pointer vacuum meter shows an atmospheric pressure after, stop ventilation, then sampling.
Description of drawings
Accompanying drawing is transparent tube type resistance furnace structural representation;
Wherein: 1 flowmeter, 2. needle-valve, 3. pointer vacuum meter, 4. vacuum adapter coupling, 5. suprasil shell, 6. transparent heating tube, 7. heating wire, 8. quartz liner, 9. electron vacuum gage, 10. vacuum flapper valve, 11. vacuum insulation chamber blast pipes, 12. furnace body supports, 13. thermocouples.
The specific embodiment
1,Concrete structure of the present invention comprises inlet end, body of heater and outlet side three parts.Inlet end arranges flowmeter 1 and needle-valve 2, pointer vacuum meter 3, vacuum adapter coupling 4, is used for the regulation and control carrier gas and enters.Body of heater comprises furnace body support 12, suprasil shell 5 and transparent heating tube 6, and cavity is the vacuum insulation chamber between suprasil shell 5 and the transparent heating tube 6, heating wire 7 is wound on transparent heating tube 6 outer walls.The vacuum insulation chamber is connected with vacuum insulation chamber blast pipe 11, and thermocouple 13 is fixed in transparent heating tube 6 outsides, in order to monitoring temperature, is provided with a suprasil bushing pipe 8 in the transparent heating tube 6, and furnace body support 12 supports body of heater.The outlet side comprises electron vacuum gage 9, and vacuum flapper valve 10 and bellows vacuum chain jointed tubular workpieces couple together part and the mechanical pump that needs in the stove to find time.Inlet end, body of heater are connected the KF flange and connect with the outlet side, by these connector sampling blowings.
Transparent tube type resistance furnace thermal treatment zone heating wire 7 adopts nickel filament as heater, the nickel filament diameter is 0.7mm, be rolled into the spring-like that external diameter is 3mm, make overall length be about 30cm, adjust the distribution of humidity province by the density of adjusting the winding of Nie Chrome silk, guarantee respectively to enclose between the resistance wire during winding not contact, resistance wire is by the control of controllable silicon PID temperature controller, and maximum power output is set as 90% of used Nie Chrome silk rated power.
2, transparent tube type resistance furnace uses embodiment in the preparation of CuPc micro Nano material:
When 1) preparing the CuPc nano wire, the high-temperature region is set in apart from inlet end 15-20cm usually, and thermocouple also is fixed on this position;
2) clean silicon substrate with the standard silicon chip cleaning, quartz liner is cleaned with the concentrated sulfuric acid, then uses deionized water
Repeatedly flushing oven dry then is put into silicon substrate in the bushing pipe, and a certain amount of CuPc of weighing is put in the silica crucible, pushes in the bushing pipe, then bushing pipe is pushed in the heating tube, adjusts the position so that raw material is in the position of thermocouple, connects the vacuum adapter coupling.
3) closing baffle plate valve and needle-valve are opened vavuum pump, and insulation chambers is found time, and then slowly open the vavuum pump baffle plate
Valve is evacuated down to 1Pa, and then opening argon gas needle-valve adjustment flow is 200-300sccm, and the regulating fender valve is so that pressure maintains about 10Pa;
4) set heating curve, after 300 ℃, slowly heat up, observe inner quartz liner inwall and when open
Begin to occur blue, at this moment, the temperature T of record high-temperature region
0, this is the sublimation point of CuPc.
5) than T
0High 10-30 ℃ temperature is incubated half an hour, the scope of observing final crystallizing field, if
Crystallizing field length fails to reach 15-20cm, then needs the adjusting resistance silk to distribute, and the density of the resistance wire of crystallizing field is changed regulate slowly, elongates like this crystallizing field, guarantees purity and the degree of crystallinity of formed micro-nano monocrystalline.
6) after reaction is finished, close first carrier gas, flapper valve cuts out vavuum pump again, and venting in the backward insulation chambers,
Can realize fast cooling like this.
7) by the time temperature drops to enough lowly, open needle-valve, pass into carrier gas, wait until pointer vacuum meter show one large
Behind the air pressure, stop ventilation, then sampling.
8) parameter of then setting according to for the first time test is carried out primary first-order equation again, the proper extension reaction time,
Observe the phenomenon in raw material district, can both meet the demands if CuPc rate of sublimation and crystallizing field distribute, then the stove debugging is complete.
Claims (2)
1. all-transparent tube type resistance furnace, it is characterized in that concrete structure comprises inlet end, body of heater and outlet side three parts, inlet end arranges flowmeter (1) and needle-valve (2), pointer-type vacuum meter (3), vacuum adapter coupling (4), body of heater comprises furnace body support (12), suprasil shell (5) and transparent heating tube (6), cavity is the vacuum insulation chamber between suprasil shell (5) and the transparent heating tube (6), heating wire (7) is wound on transparent heating tube (6) outer wall, the vacuum insulation chamber is connected with vacuum insulation chamber blast pipe (11), thermocouple (13) is fixed in transparent heating tube (6) outside, be provided with a suprasil bushing pipe (8) in the transparent heating tube (6), furnace body support (12) supports body of heater, the outlet side comprises electron vacuum gage (9), and vacuum flapper valve (10) and bellows vacuum chain jointed tubular workpieces couple together inlet end with part and the mechanical pump that needs in the stove to find time, body of heater is connected the KF flange and connects with the outlet side, by these connector sampling blowings.
2. by a kind of all-transparent tube type resistance furnace claimed in claim 1, it is characterized in that tube type resistance furnace thermal treatment zone heating wire (7) adopts nickel filament as heater, the nickel filament diameter is 0.7mm, be rolled into the spring-like that external diameter is 3mm, making overall length is 30cm, adjust the distribution of humidity province by the density of adjusting the winding of Nie Chrome silk, resistance wire is by the control of controllable silicon PID temperature controller, and maximum power output is set as 90% of used Nie Chrome silk rated power.
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| CN201210076605XA CN103322800A (en) | 2012-03-22 | 2012-03-22 | Fully transparent tube type resistance furnace |
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| CN201210076605XA CN103322800A (en) | 2012-03-22 | 2012-03-22 | Fully transparent tube type resistance furnace |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104089976A (en) * | 2014-07-09 | 2014-10-08 | 安徽工业大学 | Observable device applied to solid fuel combustion mechanism research |
| CN104962721A (en) * | 2015-07-13 | 2015-10-07 | 于茜 | Heat treatment method and heat treatment equipment for continuous strip-traveling type materials |
| CN105063526A (en) * | 2015-07-29 | 2015-11-18 | 无锡市东杨电子有限公司 | Nickel strap heat treatment device and technology |
| CN106403602A (en) * | 2016-09-12 | 2017-02-15 | 中国航空工业集团公司北京航空材料研究院 | Heating furnace for creeping and stress rupture test for muffle furnace structure |
| CN108120282A (en) * | 2016-11-28 | 2018-06-05 | 登封市宏远电热元件有限公司 | A kind of tube furnace with nitrogen protection |
| CN110904410A (en) * | 2019-12-17 | 2020-03-24 | 北京工业大学 | Equipment and method for preparing magnesium oxide-based film with high secondary emission performance |
| CN113560691A (en) * | 2021-08-11 | 2021-10-29 | 西北电子装备技术研究所(中国电子科技集团公司第二研究所) | Eutectic furnace control method capable of effectively improving uniformity of eutectic temperature in furnace |
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| CN101308077A (en) * | 2008-06-17 | 2008-11-19 | 中国科学院过程工程研究所 | Apparatus and method for measuring middle and low-temperature smelt surface tension, density and wettability |
| CN201152787Y (en) * | 2007-12-24 | 2008-11-19 | 陕西科技大学 | Apparatus for measuring foaming temperature of foam glass |
| CN202057186U (en) * | 2010-11-26 | 2011-11-30 | 洛阳市西格马仪器制造有限公司 | High temperature high pressure high vacuum resistant tube furnace |
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2012
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Patent Citations (5)
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| US3626154A (en) * | 1970-02-05 | 1971-12-07 | Massachusetts Inst Technology | Transparent furnace |
| JPS63127072A (en) * | 1986-10-28 | 1988-05-30 | デンパック コーポレーション | High-temperature vacuum furnace |
| CN201152787Y (en) * | 2007-12-24 | 2008-11-19 | 陕西科技大学 | Apparatus for measuring foaming temperature of foam glass |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104089976A (en) * | 2014-07-09 | 2014-10-08 | 安徽工业大学 | Observable device applied to solid fuel combustion mechanism research |
| CN104089976B (en) * | 2014-07-09 | 2016-08-24 | 安徽工业大学 | A kind of visual device being applied to solid fuel ignition study mechanism |
| CN104962721A (en) * | 2015-07-13 | 2015-10-07 | 于茜 | Heat treatment method and heat treatment equipment for continuous strip-traveling type materials |
| CN105063526A (en) * | 2015-07-29 | 2015-11-18 | 无锡市东杨电子有限公司 | Nickel strap heat treatment device and technology |
| CN106403602A (en) * | 2016-09-12 | 2017-02-15 | 中国航空工业集团公司北京航空材料研究院 | Heating furnace for creeping and stress rupture test for muffle furnace structure |
| CN108120282A (en) * | 2016-11-28 | 2018-06-05 | 登封市宏远电热元件有限公司 | A kind of tube furnace with nitrogen protection |
| CN110904410A (en) * | 2019-12-17 | 2020-03-24 | 北京工业大学 | Equipment and method for preparing magnesium oxide-based film with high secondary emission performance |
| CN113560691A (en) * | 2021-08-11 | 2021-10-29 | 西北电子装备技术研究所(中国电子科技集团公司第二研究所) | Eutectic furnace control method capable of effectively improving uniformity of eutectic temperature in furnace |
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Application publication date: 20130925 |