CS239216B1 - Production method of fibre crystals of alfa-oxide aluminium - Google Patents
Production method of fibre crystals of alfa-oxide aluminium Download PDFInfo
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- CS239216B1 CS239216B1 CS841803A CS180384A CS239216B1 CS 239216 B1 CS239216 B1 CS 239216B1 CS 841803 A CS841803 A CS 841803A CS 180384 A CS180384 A CS 180384A CS 239216 B1 CS239216 B1 CS 239216B1
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- Prior art keywords
- recipient
- crystals
- aluminum
- alumina
- furnace
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- 239000013078 crystal Substances 0.000 title claims abstract description 25
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 15
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 14
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 10
- 239000000835 fiber Substances 0.000 title description 9
- 239000004411 aluminium Substances 0.000 title 1
- 238000000034 method Methods 0.000 claims abstract description 26
- 238000006243 chemical reaction Methods 0.000 claims abstract description 16
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 7
- 239000001257 hydrogen Substances 0.000 claims abstract description 7
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052751 metal Inorganic materials 0.000 claims abstract description 6
- 239000002184 metal Substances 0.000 claims abstract description 6
- 230000003647 oxidation Effects 0.000 claims abstract description 4
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 4
- 239000002245 particle Substances 0.000 claims description 6
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 4
- 239000000758 substrate Substances 0.000 claims description 4
- 239000000919 ceramic Substances 0.000 claims description 3
- 239000000654 additive Substances 0.000 claims description 2
- 230000000996 additive effect Effects 0.000 claims description 2
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 claims description 2
- 229910052863 mullite Inorganic materials 0.000 claims description 2
- 239000000376 reactant Substances 0.000 claims 1
- 239000000463 material Substances 0.000 abstract 2
- 238000005272 metallurgy Methods 0.000 abstract 1
- 239000000126 substance Substances 0.000 abstract 1
- 229940024548 aluminum oxide Drugs 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- -1 aluminum halogens Chemical class 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000010431 corundum Substances 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 230000016507 interphase Effects 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- CHWRSCGUEQEHOH-UHFFFAOYSA-N potassium oxide Chemical compound [O-2].[K+].[K+] CHWRSCGUEQEHOH-UHFFFAOYSA-N 0.000 description 1
- 229910001950 potassium oxide Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- KKCBUQHMOMHUOY-UHFFFAOYSA-N sodium oxide Chemical compound [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 description 1
- 229910001948 sodium oxide Inorganic materials 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
Vynález rieši problém hromadnéj výroby vláknitých kryštálov «Α - oxidu hlinitého metódou oxidácie hliníka v atmosféře vlhkého vodika. Podstata vynálezu spočívá v tom, že kryštaly sa peatujú v recipiente tvaru trubky pozdížne rozděleně j na dve časti, pričom recipient spolu so vsádzkou sa plynule posúva cez reakč- nú zónu pece. Dlžka recipienta ie mnohonásobné vačšia ako dlžka tejto zóny. Vynález je možno využit v odbore Chemická teohnológia kovovýoh a špeoiálnýoh materiálov a v odbore metalurgie a medzné stavy materiálov.The invention solves the problem of mass production of Α-alumina fibrous crystals by the aluminum oxidation method in a moist hydrogen atmosphere. The essence of the invention is that the crystals are heated in a tube-shaped reciprocating compartment divided into two parts, the recipient, together with the batch, continuously passing through the reaction zone of the furnace. The length of the recipient is multiple than the length of the zone. The invention can be used in the field of Chemical Theology of Metal and Special Materials, and in the field of Metallurgy and Material Limit States.
Description
Vynález sa týká sposobu výroby vláknitých kryštálov /whiskerov/ eó - oxidu hlinitého z plynnej fázy v pohyblivom recipiente, dlžka ktorého mnohonásobné převyšuje dížku reakčnej zóny pece.The present invention relates to a process for the production of fibrous crystals / whiskers / eo-alumina from a gas phase in a moving recipient, the length of which exceeds many times the length of the reaction zone of the furnace.
Monokryštály kovov a mnohých chemických zlúčenín v tvare tenkých vláken sa vyznačujú celým radom velmi zaujímavých vlastností, z ktorých najvačšiu pozornost vzbudzuje ich vysoká mechanická pevnost. Táto pri velmi malých prierezoch kryštálov dosahuje hodnoty blízké k hodnotám teoretickým. Kryštály v tvare tenkých vláken sú zaujímavé nielen ako objekty vhodné pre štúdium mimoriadne dokonalej vnútornej štruktúry, ale možno ich využit i v technickéj praxi, napr. v jemnej přístroj ověj technike, v mikrotechnike, pri výrobě vláknových kompozitných materiálov a pod.The monocrystals of metals and many chemical compounds in the form of thin fibers are characterized by a number of very interesting properties, of which their high mechanical strength attracts the most attention. With very small crystal cross-sections, this achieves values close to theoretical. Crystals in the form of thin fibers are interesting not only as objects suitable for studying extremely perfect internal structure, but can also be used in technical practice, eg. in fine instrumentation, in microtechnology, in the production of fiber composite materials and the like.
Zo známých kryštálov v tvare tenkých vláken našli najváčšie uplatnenie kryštály fázy oC - oxidu hlinitého. Vyrábajú sa najčastejšie z hliníka pomocou vysokoteplotných plynofázových transportných reakcií, pri ktorých dochádza k postupnej transformácii východiskovej suroviny, umiestnenej v recipiente,na plynné medzifázy, ktoré na vhodnej podložke kondenzujú na produkt vláknitého tvaru.Of the known thin-fiber crystals, the oC-alumina phase crystals have found the greatest application. They are mostly made of aluminum by means of high-temperature gas-phase transport reactions, in which the starting material placed in the recipient is gradually transformed into gaseous interphases, which condense into a filament-shaped product on a suitable support.
Pri doterajších spósoboch výroby vláknitých kryštálov oó- oxidu hlinitého z plynnéj fázy sa používajú známe metody oxidácie hliníka vo vlhkom vodíku, redukcie halogéngv hliníka pri jeho súčasnej oxidáoii a transformácia monokryštalického alebo polykryštalického makroskopického substrátu na kryštály v tvare vláken. Najznámejšia z týchto metod je metoda oxidácie hliníka v atmosféře vlhkého vodíka. Princip tejto metody spočívá v tom, že hliník umiestnený vo vhodnom recipiente sa zohrieva niekoTko hodin na teploty 1 300 až 1 450 °C v prúde vlhkého vodíka s rosným bodom cca - 30 °C. Pri styku vodnej páry s roztaveným hliníkom dochádza k jeho oxidácii za vzniku plynných ne- 2 239 216 stabilnýoh oxid·v klinika, které na vhednej podložke prechádzajú na stabilný -exid hlinitý v tvare tenkých vláčen. Jeden pracovný cyklus pozostáva z ohřevu vsádzky na reakčnú teplotu, z výdrže na tejto teplote, kedy dochádza k vzniku vláknového produktu a z pomalého echladzevania na normglnu teplotu. Pri deterajších sposoboch výroky vláknitých kryštálov -oxidu hlinitého metodou oxidácie hliníka v atmosféře vlhkého vedíka sa použíbali recipienty róznehe zleženia, tvaru a velkosti. Najčastejšie to běli lodičky a téjliky vyrobené z čistého korundu, z kremeňa, zo zmesi exidev modifikovaných přísadami róznych kovov alebo bez týchto přísad a pod. Ich společným znakem je te, že recipient spolu so vsádzkou je vždy umiestnený do středu reakčnej zeny pece, rozměry recipienta neprevyšujú rozměry tejto zóny a počas vytvárania vláknového produktu recipient nemení vzhladom na reakčnú zenu sveju polohu. Kryštály sa pri týchto sposoboch vytvárajú na relativ ne malej podložke tveřenej iba malou častou vnútorného povrchu recipienta, takže rozměry vznikajúceho produktu sú vždy menšie ako sú rozměry reakčnej zóny pece. Nevýhodou týchto spósebev je to, že sa vyznačujú velmi malou produktivitou; v rámci jedného pracovného cyklu sa získá produkt malých rozmerov a malej hmotnosti. Ďalšeu nevýhodou je to, že vznikajúce produkty majú nízku kvalitu; sú značné heterojénne z hladiska čistoty a rozmerov krystálov. Výťažnost kvalitných kryštálov z takýchto produktov je velmi nízká a preto tieto spósoby sú značné neekonomické a možno ich použit iba v laboratórijych podmienkach, na přípravu malého množstva kryštálov.The prior art processes for producing o-alumina fibrous crystals from the gas phase employ known methods of oxidizing aluminum in moist hydrogen, reducing aluminum halogens in its simultaneous oxidation, and transforming monocrystalline or polycrystalline macroscopic substrates into fiber-shaped crystals. The best known of these methods is the method of oxidizing aluminum in a humid hydrogen atmosphere. The principle of this method is that the aluminum placed in a suitable recipient is heated for several hours to temperatures of 1,300 to 1,450 ° C in a stream of humid hydrogen with a dew point of about - 30 ° C. When water vapor comes into contact with the molten aluminum, it oxidizes to form gaseous or unstable oxides in the clinic, which are converted to a stable, thin-stranded aluminum oxide on a base. One cycle consists of heating the batch to the reaction temperature, holding at this temperature, where the fiber product is formed, and slowly cooling to normal temperature. In the prior art, alumina fiber crystal crystals have been used by recipients of varying composition, shape and size by the method of oxidizing aluminum in a humid bucket atmosphere. Most often it was bleached and made of pure corundum, quartz, a mixture of exidevs modified with or without the addition of non-ferrous metals, and the like. Their common feature is that the recipient together with the charge is always placed in the center of the reaction wall of the furnace, the dimensions of the recipient do not exceed the dimensions of this zone and the recipient does not change its position during the formation of the fiber product. In these processes, crystals are formed on a relatively small substrate formed by only a small portion of the recipient's internal surface, so that the dimensions of the product formed are always smaller than the dimensions of the reaction zone of the furnace. The disadvantage of these methods is that they are characterized by very low productivity; within one working cycle, a product of small size and light weight is obtained. A further disadvantage is that the resulting products are of poor quality; they are considerably heterogeneous in terms of crystal purity and dimensions. The yield of quality crystals from such products is very low and therefore these methods are considerable uneconomical and can only be used in laboratory conditions to prepare small quantities of crystals.
Nedostatky uvedených spósobov odstraňuje spósob výroby vláknitých kryštálov -oxidu hlinitého metodou oxidácie hliníka v atmosféře vlhkého vodíka s rosným bodom od -10 do -60 0 C pri teplote 1350 až 1450 °C, ktorého podstatou je, že do reakčného recipienta z oxidu hlinitého alebo mullitu sa umiestni vsádzka tvořená hliníkom s veIkostou častíc de 3 mm s přísadou oxidu hlinitého s velkosťou častíc do 100/um v množstve 1 až 20 % hmotnostných vztiahnuté na hmotnost hliníka a reakčný recipient sa posúva cez reakčnú zónu pece rýchlosťou 0,1 až 10 mm.rain*^, pričom dížka reakčnej zóny pece je 0,01 až 1 násobkem dížky recipienta.The disadvantages of the above methods are eliminated by the method of production of aluminum-oxide fibrous crystals by the method of oxidation of aluminum in a humid hydrogen atmosphere with a dew point of -10 to -60 ° C at a temperature of 1350 to 1450 ° C. An aluminum oxide particle size of 3 mm with an alumina additive having a particle size of up to 100 µm in an amount of 1 to 20% by weight based on the weight of aluminum is placed and the reaction recipient is moved through the reaction zone of the furnace at a rate of 0.1 to 10 mm. rain, wherein the length of the reaction zone of the furnace is 0.01 to 1 times the length of the recipient.
Vsádzka je uložená na kovověj alebo keramickej podložke,alebo je velne uložená na dne recipienta. Recipient má tvar trubice s kruhovým alebo iným prierezom a je pozdížne rozdělený na dve časti.The charge is deposited on a metal or ceramic substrate, or is largely deposited on the bottom of the recipient. The recipient has the shape of a tube with a circular or other cross-section and is divided into two parts.
Výhodou uvedeného spósobu výroby vláknitých kryštálovAn advantage of said method for producing fibrous crystals
- 3 - 239 216 ot- oxidu hlinitého je vysoká produktivita procesu na jeden pracovny cyklus» úspora oasu a energie v dosledku zníženia počtu neproduktívnych fáz procesu pri ohřeve a ochladzovaní vsádzky, menšie opotrebovanie zariadenia v dosledku zníženia počtu tepelných rázov, vysoká kvalita získaného produktu a možnost automatizácie celého výrobného procesu. Výhodou uvedeného sposobu je tiež to, že reakčnú zónu procesu je možné vytvořit pomocou jednoduchej priechodovej trubicovej pece, ktorej dížka vysokoteplotnej zóny. nemusí byť vačšia ako 100 mm.- 3 - 239 216 ot-alumina is high process productivity per cycle »saving of time and energy due to reduced number of unproductive phases of the process in heating and cooling the batch, less equipment wear due to reduced thermal shock, high product quality and the possibility of automating the entire production process. An advantage of said method is also that the reaction zone of the process can be formed by means of a single through tube furnace whose length of the high temperature zone. need not be greater than 100 mm.
Na připojených obrázkoch 1 a 2 je znázorněný pohyblivý recipient použitý pri sposobe výroby vláknitých kryštálov ©č-oxidu hlinitého podlá vynálezu. Na obrázku 1 je recipient spolu so vsádzkou připravený na vloženie do pece a na obrázku 2 je ten istý recipient po přechode cez reakčnú zónu pece. Recipient má tvar trubky skladajúcej ša zo spodnej časti 2 v ktorej sa nachádza vsádzka 1 umiestnená na kovověj alebo keramickej lodičke 2 a z odklopného viečka £» ktoré plní funkciu podložky, ná ktorej prebieha nukleácia a rast kryštálov. Viečko £ je odnímatelné a umožňuje lahký přístup ku vsádzke a k vláknovému produktu 5.·Referring to Figures 1 and 2, a moving recipient used in a process for producing fibrous ©-alumina crystals according to the invention is shown. In Figure 1, the recipient together with the batch is ready to be loaded into the furnace, and in Figure 2 the same recipient is passed through the reaction zone of the furnace. The recipient has the shape of a tube consisting of a bottom part 2 in which the charge 1 is located on a metal or ceramic boat 2 and a hinged lid 6 which serves as a support for nucleation and crystal growth. The lid £ is removable and allows easy access to the charge and fiber product 5. ·
Na plynulé posúvanie recipienta cez reakčnú zónu pece slúži tiahlo 6.The rod 6 is used to continuously move the recipient through the furnace reaction zone.
Sposob výroby vláknitých kryštálov oč- oxidu hlinitého podlá vynálezu bol použitý pri hromadnej výrobě týchto kryštálov, pričom ako vsádzka sa použila prášková zmes hliníka o velkosti častíc v rozsahu 8 až 50 yum a oxidu hlinitého o velkosti častíc 50 až 80 /um. Poměr hmotnostných podielov hliníka a oxidu hlinitého bol 10*1. Recipient bol vyrobený z mullitu s obsahom 71,7 % hmot. oxidu hlinitého, 25,8 % hmot. oxidu křemičitého a zvyšok tvořili oxid železitý, oxid vápenatý, oxid horečnatý, oxid sodný a oxid draselný. Mal tvar trubky s vonkajším priemerom 38 mm a hrubkou steny 2 mm. Jeho dížka bola 400 mm. Kryštály boli pěstované pri teplote 1 380 až 1 400 °C v atmosféře vlhkého vodíka s rosným bodom - 40 °C. Na pestovanie sa použila priechodná trubicová pec s reakčnou zónou o priemere 47 mm a dížke 100 mm. Rýchlosť posuvu recipienta bola 4 mm min Produktivita procesu na jeden pracovný cyklus sa zvýšila v porovnaní so statickým” recipientom viac ako 20 krát.The process for the production of fibrous crystals of alumina according to the invention has been used in the mass production of these crystals using a powder mixture of a particle size of 8 to 50 µm and a particle size of 50 to 80 µm. The ratio by weight of aluminum to alumina was 10 * 1. The recipient was made of mullite containing 71.7 wt. % alumina, 25.8 wt. silica and the remainder were iron oxide, calcium oxide, magnesium oxide, sodium oxide and potassium oxide. It had a tube shape with an outer diameter of 38 mm and a wall thickness of 2 mm. Its length was 400 mm. The crystals were grown at a temperature of 1,380 to 1,400 ° C in a humid hydrogen atmosphere with a dew point of -40 ° C. A through-furnace tube with a reaction zone of 47 mm diameter and 100 mm length was used for cultivation. The recipient feed rate was 4 mm min. Process productivity per cycle increased more than 20 times the static recipient.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS841803A CS239216B1 (en) | 1984-03-13 | 1984-03-13 | Production method of fibre crystals of alfa-oxide aluminium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS841803A CS239216B1 (en) | 1984-03-13 | 1984-03-13 | Production method of fibre crystals of alfa-oxide aluminium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CS180384A1 CS180384A1 (en) | 1985-05-15 |
| CS239216B1 true CS239216B1 (en) | 1986-01-16 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CS841803A CS239216B1 (en) | 1984-03-13 | 1984-03-13 | Production method of fibre crystals of alfa-oxide aluminium |
Country Status (1)
| Country | Link |
|---|---|
| CS (1) | CS239216B1 (en) |
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1984
- 1984-03-13 CS CS841803A patent/CS239216B1/en unknown
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| Publication number | Publication date |
|---|---|
| CS180384A1 (en) | 1985-05-15 |
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