JPH0351680B2 - - Google Patents
Info
- Publication number
- JPH0351680B2 JPH0351680B2 JP61301969A JP30196986A JPH0351680B2 JP H0351680 B2 JPH0351680 B2 JP H0351680B2 JP 61301969 A JP61301969 A JP 61301969A JP 30196986 A JP30196986 A JP 30196986A JP H0351680 B2 JPH0351680 B2 JP H0351680B2
- Authority
- JP
- Japan
- Prior art keywords
- silicon
- silicon carbide
- carbon
- raw material
- reaction
- 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 - Lifetime
Links
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 49
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 claims description 48
- 239000002994 raw material Substances 0.000 claims description 42
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 41
- 238000006243 chemical reaction Methods 0.000 claims description 39
- 229910052799 carbon Inorganic materials 0.000 claims description 31
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 29
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 28
- 238000004519 manufacturing process Methods 0.000 claims description 21
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 20
- 239000000203 mixture Substances 0.000 claims description 9
- 230000001590 oxidative effect Effects 0.000 claims description 7
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 6
- 239000000843 powder Substances 0.000 claims description 6
- 238000002955 isolation Methods 0.000 claims description 4
- 238000009423 ventilation Methods 0.000 claims description 4
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 239000011863 silicon-based powder Substances 0.000 claims description 3
- 239000010703 silicon Substances 0.000 description 26
- 229910052710 silicon Inorganic materials 0.000 description 23
- 238000000034 method Methods 0.000 description 16
- 239000000377 silicon dioxide Substances 0.000 description 11
- 235000012239 silicon dioxide Nutrition 0.000 description 10
- 239000007789 gas Substances 0.000 description 7
- 239000000047 product Substances 0.000 description 6
- 239000006229 carbon black Substances 0.000 description 5
- 238000005192 partition Methods 0.000 description 5
- 239000012071 phase Substances 0.000 description 5
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 4
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 4
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 4
- 229910004298 SiO 2 Inorganic materials 0.000 description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 4
- 229910002091 carbon monoxide Inorganic materials 0.000 description 4
- 239000000835 fiber Substances 0.000 description 4
- 229910002804 graphite Inorganic materials 0.000 description 4
- 239000010439 graphite Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- NROKBHXJSPEDAR-UHFFFAOYSA-M potassium fluoride Chemical compound [F-].[K+] NROKBHXJSPEDAR-UHFFFAOYSA-M 0.000 description 4
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 4
- 238000010532 solid phase synthesis reaction Methods 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 239000007795 chemical reaction product Substances 0.000 description 3
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 3
- 229910052814 silicon oxide Inorganic materials 0.000 description 3
- 238000001308 synthesis method Methods 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 239000007809 chemical reaction catalyst Substances 0.000 description 2
- WMVRXDZNYVJBAH-UHFFFAOYSA-N dioxoiron Chemical compound O=[Fe]=O WMVRXDZNYVJBAH-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000002431 hydrogen Chemical class 0.000 description 2
- KWGKDLIKAYFUFQ-UHFFFAOYSA-M lithium chloride Chemical compound [Li+].[Cl-] KWGKDLIKAYFUFQ-UHFFFAOYSA-M 0.000 description 2
- PQXKHYXIUOZZFA-UHFFFAOYSA-M lithium fluoride Chemical compound [Li+].[F-] PQXKHYXIUOZZFA-UHFFFAOYSA-M 0.000 description 2
- 239000001103 potassium chloride Substances 0.000 description 2
- 235000011164 potassium chloride Nutrition 0.000 description 2
- 239000011698 potassium fluoride Substances 0.000 description 2
- 235000003270 potassium fluoride Nutrition 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- 239000011775 sodium fluoride Substances 0.000 description 2
- 235000013024 sodium fluoride Nutrition 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- 229920000049 Carbon (fiber) Polymers 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 229920000742 Cotton Polymers 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910001508 alkali metal halide Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910001615 alkaline earth metal halide Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- 239000004917 carbon fiber Substances 0.000 description 1
- 239000011203 carbon fibre reinforced carbon Substances 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 238000003763 carbonization Methods 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000005485 electric heating Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910001629 magnesium chloride Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 239000004745 nonwoven fabric Substances 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 239000012254 powdered material Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000004626 scanning electron microscopy Methods 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 235000002639 sodium chloride Nutrition 0.000 description 1
- 238000003746 solid phase reaction Methods 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
- -1 waxite Substances 0.000 description 1
- 239000002759 woven fabric Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
- C30B25/005—Growth of whiskers or needles
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/36—Carbides
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、炭化ケイ素ウイスカーの製造方法に
関し、詳しくは、高純度で直線性にすぐれる炭化
ケイ素ウイスカーを高収率にて製造する方法に関
する。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for producing silicon carbide whiskers, and more particularly, to a method for producing silicon carbide whiskers with high purity and excellent linearity at a high yield.
従来の技術
炭化ケイ素ウイスカーは、軽量、高強度、高弾
性を有し、近年、複合材料の強化材として、種々
の用途が期待されている。BACKGROUND ART Silicon carbide whiskers are lightweight, have high strength, and high elasticity, and have recently been expected to be used in various ways as reinforcing materials for composite materials.
このような炭化ケイ素ウイスカーの製造方法は
従来、炭素を含む原料及びケイ素を含む原料の一
方又は両方を気相にて反応炉内の所定の高温の反
応域に供給する気相合成法と、炭素を含む原料及
びケイ素を含む原料として共に固体を用いる固相
合成法とに大別される。気相合成法は、例えば、
特公昭50−18480号公報、特公昭52−28757号公
報、特公昭52−28759号公報等に記載されており、
また、固相合成法は、例えば、特開昭58−20799
号公報、特開昭58−45918号公報、特開昭58−
145700号公報等に記載されている。 Conventionally, methods for producing such silicon carbide whiskers include a gas phase synthesis method in which one or both of a carbon-containing raw material and a silicon-containing raw material are supplied in a gas phase to a predetermined high-temperature reaction zone in a reactor, and a carbon It is broadly divided into solid-phase synthesis methods that use solids as raw materials containing silicon and silicon-containing raw materials. For example, the vapor phase synthesis method is
It is described in Japanese Patent Publication No. 50-18480, Japanese Patent Publication No. 52-28757, Japanese Patent Publication No. 52-28759, etc.
In addition, the solid phase synthesis method is, for example, JP-A No. 58-20799
No. 45918, JP 58-45918, JP 58-
It is described in Publication No. 145700, etc.
上記のような従来の気相合成法は、一般に、針
状結晶を得るには有利であるが、反面、気相原料
の利用率が著しく低い、気相原料が反応炉内で分
解し、反応炉がこれら分解物によつて汚染され
る、更に、生成した炭化ケイ素ウイスカー中にこ
れら分解物が混入する等の問題を有しているの
で、炭化ケイ素ウイスカーの大量生産には不適当
であり一方、従来の固相合成法によれば、ケイ素
を含む原料粉末と炭素を含む原料粉末とを混合
し、これを加熱して、主としてこれら粉末間の固
相反応にて直接に炭化ケイ素を生成させるので、
粉状乃至屈曲状の炭化ケイ素を多く生成し、直線
性にすぐれる炭化ケイ素ウイスカーを得ることが
困難であるほか、得られた炭化ケイ素ウイスカー
から上記のような粉状乃至屈曲状の炭化ケイ素を
分離除去することが容易ではない。 The conventional gas phase synthesis method described above is generally advantageous in obtaining needle-shaped crystals, but on the other hand, the utilization rate of the gas phase raw material is extremely low, and the gas phase raw material decomposes in the reactor, causing the reaction to occur. However, it is not suitable for mass production of silicon carbide whiskers because the furnace is contaminated with these decomposed products and furthermore, these decomposed products are mixed into the produced silicon carbide whiskers. According to the conventional solid-phase synthesis method, silicon-containing raw material powder and carbon-containing raw material powder are mixed, heated, and silicon carbide is directly produced mainly through a solid-phase reaction between these powders. So,
It is difficult to obtain silicon carbide whiskers with excellent linearity due to the generation of a large amount of powdered or bent silicon carbide, and it is also difficult to obtain the above-mentioned powdered or bent silicon carbide from the obtained silicon carbide whiskers. It is not easy to separate and remove.
そこで、本発明者らは、炭素含有原料として炭
素粉末を用い、ケイ素含有原料として二酸化ケイ
素を含有する所定形状の成形体を用いる方法を既
に提案している。この方法によれば、成形体の反
応残分としてのケイ素が生成する炭化ケイ素ウイ
スカーに混入することがなく、従つて、生成する
炭化ケイ素ウイスカーには、その生成時に副生す
るケイ素及び／又は二酸化ケイ素が微量に混入す
るにすぎない。また、反応残分としての炭素は、
反応終了後に反応生成物を大気中で燃焼させるこ
とによつて容易に除去することができるので、高
純度の炭化ケイ素ウイスカーを得ることができ
る。 Therefore, the present inventors have already proposed a method in which a carbon powder is used as the carbon-containing raw material and a molded body having a predetermined shape containing silicon dioxide is used as the silicon-containing raw material. According to this method, silicon as a reaction residue of the compact does not mix with the silicon carbide whiskers produced, and therefore, the silicon carbide whiskers produced contain silicon and/or dioxide by-product during the production. Only a trace amount of silicon is mixed in. In addition, carbon as a reaction residue is
After the reaction is completed, the reaction product can be easily removed by burning it in the atmosphere, so that highly pure silicon carbide whiskers can be obtained.
しかし、上記の方法によれば、別の問題とし
て、予めケイ素含有原料を所定形状に成形する必
要があるうえに、反応における成形体の原料とし
ての利用率が低い。 However, another problem with the above method is that it is necessary to mold the silicon-containing raw material into a predetermined shape in advance, and the utilization rate of the molded body as a raw material in the reaction is low.
発明が解決しようとする問題点
本発明らは、炭化ケイ素ウイスカーの製造にお
ける上記した問題を解決するために鋭意研究した
結果、固相合成法において、反応容器内に一酸化
ケイ素発生域と炭化ケイ素生成域とを通気下に隔
離して配設し、ケイ素含有原料と炭素含有原料と
を非酸化性雰囲気下に所定の反応温度に加熱する
ことによつて、高純度で直線性にすぐれる炭化ケ
イ素ウイスカーを高収率にて製造しうることを見
出して本発明に至つたものである。Problems to be Solved by the Invention As a result of intensive research in order to solve the above-mentioned problems in the production of silicon carbide whiskers, the present inventors have found that, in a solid phase synthesis method, a silicon monoxide generating region and a silicon carbide Carbonization with high purity and excellent linearity can be achieved by arranging the production zone in isolation under ventilation and heating the silicon-containing raw material and the carbon-containing raw material to a predetermined reaction temperature in a non-oxidizing atmosphere. The present invention was achieved by discovering that silicon whiskers can be produced in high yield.
問題点を解決するための手段
本発明による炭化ケイ素ウイスカーの製造方法
は、反応容器内に一酸化ケイ素発生域と炭素含有
原料を含む炭化ケイ素生成域とを通気下に隔離し
て配設し、非酸化性雰囲気下に1400〜1700℃の温
度に加熱することを特徴とする。Means for Solving the Problems The method for producing silicon carbide whiskers according to the present invention comprises arranging a silicon monoxide generation region and a silicon carbide generation region containing a carbon-containing raw material in isolation under ventilation in a reaction vessel, It is characterized by heating to a temperature of 1400-1700°C under a non-oxidizing atmosphere.
本発明において、一酸化ケイ素発生域は、通
常、反応容器内におけるケイ素含有原料の充填層
によつて形成される。ここに、上記ケイ素含有原
料としては、好ましくは、金属ケイ素粉末と二酸
化ケイ素粉末との混合物、二酸化ケイ素粉末と炭
素粉末との混合物、一般化ケイ素等を用いること
ができる。上記二酸化ケイ素粉末としては、例え
ば、ケイ石、銀砂、ロウ石、粘土等を用いること
が有利である。 In the present invention, the silicon monoxide generating zone is usually formed by a packed bed of silicon-containing raw material within the reaction vessel. Here, as the silicon-containing raw material, preferably, a mixture of metal silicon powder and silicon dioxide powder, a mixture of silicon dioxide powder and carbon powder, generalized silicon, etc. can be used. As the silicon dioxide powder, it is advantageous to use, for example, silica stone, silver sand, waxite, clay, or the like.
また、炭化ケイ素生成域は、通常、反応容器内
における炭素含有原料の充填層から形成される。
炭素含有原料としては、カーボンブラツクや粉末
活性炭等の粉末状のものが好ましく用いられる。
本発明の方法においては、一酸化ケイ素と固体炭
素との接触によつて炭化ケイ素ウイスカーが生成
するので、上記のような粉末状炭素を用いるとき
は、炭化ケイ素ウイスカーは、炭素粉末の表面や
粉末間の空隙に生成する。従つて、炭素粉末は、
微粉であつて、嵩高いほど反応性が高いので、特
にカーボンブラツクが好ましい。しかし、必要に
応じて、グラフアイト板も用いることができる。 Additionally, the silicon carbide production zone is typically formed from a packed bed of carbon-containing feedstock within a reaction vessel.
As the carbon-containing raw material, powdered materials such as carbon black and powdered activated carbon are preferably used.
In the method of the present invention, silicon carbide whiskers are generated by contacting silicon monoxide with solid carbon, so when using powdered carbon as described above, silicon carbide whiskers are generated on the surface of carbon powder or Generates in the space between. Therefore, carbon powder is
Carbon black is particularly preferred because it is a fine powder and the more bulky it is, the higher the reactivity is. However, graphite plates can also be used if necessary.
本発明の方法においては、反応触媒を用いるこ
とが好ましい。反応触媒としては、鉄、ニツケ
ル、コバルト、又はこれらの化合物、例えば、酸
化物、硝酸塩、塩化物、硫酸塩、炭酸塩等が粉末
又は水溶液として炭素原料に混合されて用いられ
る。 In the method of the present invention, it is preferred to use a reaction catalyst. As the reaction catalyst, iron, nickel, cobalt, or compounds thereof, such as oxides, nitrates, chlorides, sulfates, carbonates, etc., are used as a powder or an aqueous solution mixed with the carbon raw material.
更に、本発明においては、反応を促進すると共
に、高純度で且つ針状であり、更に、嵩密度の小
さい炭化ケイ素ウイスカーを得るために、必要に
応じて、反応促進剤を用いることができる。この
ような反応促進剤としては、アルカリ金属又はア
ルカリ土類金属のハロゲン化物、特に、塩化物又
はフツ化物を好適に用いることができる。従つ
て、具体例としては、塩化リチウム、塩化ナトリ
ウム、塩化カリウム、塩化カルシウム、塩化マグ
ネシウム、フツ化リチウム、フツ化ナトリウム、
フツ化カリウム等を挙げることができる。これら
のなかでも特に好ましい反応促進剤は、塩化ナト
リウム、塩化カリウム、フツ化ナトリウム及びフ
ツ化カリウムである。 Furthermore, in the present invention, a reaction accelerator can be used as necessary in order to accelerate the reaction and obtain silicon carbide whiskers that are highly pure, acicular, and have a low bulk density. As such a reaction accelerator, an alkali metal or alkaline earth metal halide, particularly a chloride or a fluoride, can be suitably used. Therefore, specific examples include lithium chloride, sodium chloride, potassium chloride, calcium chloride, magnesium chloride, lithium fluoride, sodium fluoride,
Examples include potassium fluoride. Among these, particularly preferred reaction accelerators are sodium chloride, potassium chloride, sodium fluoride, and potassium fluoride.
本発明の方法においては、反応容器内において
上記したようにケイ素含有原料と炭素含有原料と
を通気下に隔離して充填して、それぞれ一酸化ケ
イ素発生域と炭化ケイ素生成域とを形成し、非酸
化性雰囲気下に上記原料を加熱して、一酸化ケイ
素発生域から一酸化ケイ素気体を発生させ、これ
を炭化ケイ素生成域に導いて、炭素との反応によ
つて、炭化ケイ素ウイスカーを生成させる。 In the method of the present invention, a silicon-containing raw material and a carbon-containing raw material are charged in isolation under ventilation as described above in a reaction vessel to form a silicon monoxide generation zone and a silicon carbide generation zone, respectively; The above raw materials are heated in a non-oxidizing atmosphere to generate silicon monoxide gas from the silicon monoxide generation zone, which is led to the silicon carbide generation zone and reacts with carbon to generate silicon carbide whiskers. let
上記非酸化性雰囲気は、好ましくは、水素ガス
雰囲気である。ここに、水素ガス雰囲気とは、水
素ガスのみの場合だけでなく、20容量％以上の水
素を含有し、残部が不活性ガスである雰囲気をも
含むものとする。 The non-oxidizing atmosphere is preferably a hydrogen gas atmosphere. Here, the hydrogen gas atmosphere includes not only hydrogen gas but also an atmosphere containing 20% by volume or more of hydrogen, with the remainder being an inert gas.
本発明の方法においては、炭化ケイ素ウイスカ
ーは、以下のような反応によつて生成するものと
みられる。即ち、一酸化ケイ素生成域がケイ素と
二酸化ケイ素とからなる場合は、反応(1)によつて
一酸化ケイ素を生成する。また、二酸化ケイ素と
炭素とからなる場合は、反応(2)によつて一酸化ケ
イ素と一酸化炭素とを生成する。炭素はまた、水
素との反応(3)によつてメタンを生成し、反応(4)に
よつてこのメタンが二酸化ケイ素と反応して一酸
化ケイ素と一酸化炭素を生成する。更に、このほ
かにも、二酸化ケイ素と上記一酸化炭素との反応
(5)による一酸化ケイ素と二酸化炭素の生成や、二
酸化炭素と炭素との反応(6)による一酸化炭素の生
成等も起こるとみられる。 In the method of the present invention, silicon carbide whiskers are thought to be produced by the following reaction. That is, when the silicon monoxide producing region consists of silicon and silicon dioxide, silicon monoxide is produced by reaction (1). Moreover, when it is composed of silicon dioxide and carbon, silicon monoxide and carbon monoxide are produced by reaction (2). Carbon also produces methane by reaction (3) with hydrogen, which reacts with silicon dioxide to produce silicon monoxide and carbon monoxide in reaction (4). Furthermore, in addition to this, the reaction between silicon dioxide and the above carbon monoxide
The production of silicon monoxide and carbon dioxide due to (5) and the production of carbon monoxide due to the reaction between carbon dioxide and carbon (6) are also thought to occur.
他方、炭化ケイ素生成域においては、上記のよ
うにして生成した一酸化ケイ素が炭素との反応(7)
によつて炭化ケイ素ウイスカーを生成する。 On the other hand, in the silicon carbide production region, silicon monoxide produced as described above reacts with carbon (7).
to produce silicon carbide whiskers.
Si（ｓ）＋SiO2→2SiO(g) (1)
Ｃ（ｓ）＋SiO2（ｓ）→SiO(g)＋CO(g) (2)
Ｃ（ｓ）＋2H2(g)→CH4 (3)
CH4(g)＋SiO2（ｓ）
→SiO(g)＋CO(g)＋2H2 (4)
SiO2（ｓ）＋CO(g)→SiO(g)＋CO2(g) (5)
CO2(g)＋Ｃ（ｓ）→2CO(g) (6)
SiO(g)＋Ｃ→SiC（ｓ）＋CO(g) (7)
本発明の方法において、原料利用率を高めるた
めには、反応容器内において、一酸化ケイ素生成
域において発生した一酸化ケイ素を炭素含有原料
に効率よく接触させることが重要である。これを
可能とする反応容器の一例を第１図に示す。即
ち、反応容器１内には底部に例えばケイ素と二酸
化ケイ素との混合物からなるケイ素含有原料２が
底敷きされて、一酸化ケイ素生成域３が形成され
ており、その上に通気性の仕切り材４にて隔離さ
れて、例えばカーボンブラツクからなる炭素含有
原料５からなる炭化ケイ素の生成域６が形成され
ている。上記仕切り材としては、耐熱性と通気性
を有する繊維シート又は繊維塊からなるのが好ま
しく、例えば、炭化ケイ素、炭素繊維等からなる
織布や不織布、アルミナやグラフアイトの板体を
穿孔してなる多孔板が用いられる。Si(s)+SiO 2 →2SiO(g) (1) C(s)+SiO 2 (s)→SiO(g)+CO(g) (2) C(s)+2H 2 (g)→CH 4 (3) CH 4 (g) + SiO 2 (s) →SiO(g) + CO(g) + 2H 2 (4) SiO 2 (s) + CO(g) → SiO(g) + CO 2 (g) (5) CO 2 (g) )+C(s)→2CO(g) (6) SiO(g)+C→SiC(s)+CO(g) (7) In the method of the present invention, in order to increase the raw material utilization rate, in the reaction vessel, It is important to efficiently bring the silicon monoxide generated in the silicon monoxide production zone into contact with the carbon-containing raw material. An example of a reaction vessel that makes this possible is shown in FIG. That is, in the reaction vessel 1, a silicon-containing raw material 2 made of a mixture of silicon and silicon dioxide is lined at the bottom to form a silicon monoxide production region 3, and a breathable partition material is placed on top of the silicon-containing raw material 2, which is made of a mixture of silicon and silicon dioxide. 4, a silicon carbide production region 6 made of a carbon-containing raw material 5 made of carbon black, for example, is formed. The partition material is preferably made of a heat-resistant and breathable fiber sheet or fiber mass, such as a woven fabric or non-woven fabric made of silicon carbide, carbon fiber, etc., or a perforated plate of alumina or graphite. A perforated plate is used.
かかる反応容器を用いるときは、非酸化性雰囲
気下での加熱によつて、ケイ素含有原料は一酸化
ケイ素気体を生じ、これが仕切り材を透過して、
炭素含有原料中を通過する間に炭素含有原料と接
触して、炭化ケイ素ウイスカーを生成する。 When using such a reaction vessel, the silicon-containing raw material generates silicon monoxide gas by heating in a non-oxidizing atmosphere, which permeates through the partition material.
While passing through the carbon-containing feedstock, it contacts the carbon-containing feedstock to produce silicon carbide whiskers.
本発明の方法において、反応温度は少なくとも
1400℃以上であり、通常、好ましくは1500〜1700
℃の範囲である。反応温度が1400℃よりも低いと
きは、炭化ケイ素ウイスカーの生成が不十分であ
り、未反応のケイ素含有原料の残留が多い。一
方、余りに高温としても、収率の向上や不純物の
低減の効果が飽和すると共に、製造費用の上昇を
招く。従つて、反応温度の上限は、通常、1700℃
程度が好ましい。加熱手段は任意であるが、電気
加熱が使用しやすい。 In the method of the invention, the reaction temperature is at least
1400℃ or higher, usually preferably 1500-1700
℃ range. When the reaction temperature is lower than 1400°C, silicon carbide whiskers are insufficiently produced and a large amount of unreacted silicon-containing raw material remains. On the other hand, if the temperature is too high, the effects of improving the yield and reducing impurities will be saturated, and the production cost will increase. Therefore, the upper limit of reaction temperature is usually 1700℃
degree is preferred. Although the heating means is arbitrary, electric heating is easy to use.
反応時間は30分乃至10時間であり、通常、２〜
６時間程度で十分である。反応時間が余りに短い
ときは、未反応原料が多量に残留し、一方、余り
に長時間反応させても、炭化ケイ素ウイスカーの
収量の増加が僅かであるので、生産性及び熱エネ
ルギー費用の観点からみて、何ら利点がない。 The reaction time is 30 minutes to 10 hours, usually 2 to 10 hours.
About 6 hours is sufficient. If the reaction time is too short, a large amount of unreacted raw materials will remain; on the other hand, if the reaction is too long, the yield of silicon carbide whiskers will increase only slightly, so it is difficult to reduce the productivity and thermal energy costs. , there is no advantage.
発明の効果
以上のように、本発明の方法によれば、単一の
反応容器内において、一酸化ケイ素を発生させ、
これを炭素含有原料からなる隔離された炭化ケイ
素生成域に導き、ここで炭素と反応させることに
よつて、炭化ケイ素を生じさせるので、生成する
炭化ケイ素ウイスカーには、ケイ素含有原料の反
応残分の混入がなく、高純度であり、しかも、針
状性にすぐれる炭化ケイ素ウイスカーを得ること
ができる。更に、反応容器へのケイ素含有原料と
炭素含有原料との充填量を調整することによつ
て、原料反応残分を僅少若しくは皆無とすること
もでき、かくして、原料の利用率を著しく高める
ことができる。Effects of the Invention As described above, according to the method of the present invention, silicon monoxide is generated in a single reaction vessel,
This is led to an isolated silicon carbide production zone made of a carbon-containing raw material, where it is reacted with carbon to produce silicon carbide, so the silicon carbide whiskers produced contain the reaction residue of the silicon-containing raw material. It is possible to obtain silicon carbide whiskers that are free from contamination, are highly pure, and have excellent acicularity. Furthermore, by adjusting the amount of silicon-containing raw material and carbon-containing raw material charged into the reaction vessel, it is possible to minimize or eliminate the raw material reaction residue, thereby significantly increasing the utilization rate of the raw material. can.
また、本発明の方法によれば、反応容器として
匣体を用いるので、炭化ケイ素ウイスカーの連続
製造に好適である。 Further, according to the method of the present invention, since a casing is used as a reaction vessel, it is suitable for continuous production of silicon carbide whiskers.
実施例
以下に実施例を挙げて本発明を説明するが、本
発明はこれら実施例により何ら限定されるもので
はない。EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples in any way.
内法が縦140mm、横140mm及び深さ50mm、上部開
放のグラフアイト製容器に金属ケイ素粉末と二酸
化ケイ素粉末との等モル比混合物44ｇを底敷き
し、その上にアルミナ繊維にて仕切りを形成し、
更に、この上に二酸化鉄１重量部当りにカーボン
ブラツク240重量部からなる混合物24ｇを充填し
た。 A graphite container with an internal dimension of 140 mm in length, 140 mm in width, and 50 mm in depth with an open top is filled with 44 g of an equimolar ratio mixture of metal silicon powder and silicon dioxide powder, and a partition is formed on top of it using alumina fiber. death,
Furthermore, 24 g of a mixture consisting of 240 parts by weight of carbon black per 1 part by weight of iron dioxide was filled thereon.
これを電気炉内に挿入し、水素雰囲気下に1600
℃の温度に４時間加熱した後、電気炉から取り出
して、反応容器底部からアルミナ繊維を含む反応
生成物を得、これを空気中、700℃の温度で燃焼
させて、残存炭素を燃焼除去させ、淡緑色綿状で
あつて、二酸化ケイ素1.4重量％を含む炭化ケイ
素ウイスカー30.3ｇを焼成物として得た。理論収
量に対する収率は83％であつた。 Insert this into an electric furnace and heat it under a hydrogen atmosphere for 1600 hrs.
After heating for 4 hours at a temperature of °C, it was taken out from the electric furnace and a reaction product containing alumina fibers was obtained from the bottom of the reaction vessel, which was then combusted in air at a temperature of 700 °C to burn off residual carbon. 30.3 g of silicon carbide whiskers, which were light green and flocculent and contained 1.4% by weight of silicon dioxide, were obtained as a fired product. The yield was 83% based on the theoretical yield.
この焼成物中をフツ酸にて洗浄した後、Ｘ線回
折した結果、β−炭化ケイ素であることが確認さ
れた。また、走査型電子顕微鏡観察によれば、粉
状や屈曲した炭化ケイ素量が少なく、針状性にす
ぐれる炭化ケイ素ウイスカーであつた。 After washing the inside of this fired product with hydrofluoric acid, it was confirmed to be β-silicon carbide by X-ray diffraction. Further, according to scanning electron microscopy, the silicon carbide whiskers had a small amount of powdered or bent silicon carbide and had excellent needle-like properties.
比較例
上記実施例と同様のグラフアイト製容器内に縦
40mm、横115mm及び厚さ８mm、二酸化ケイ素含有
量95重量％の板状成形体４枚を等間隔に配設し、
容器内の空隙部に二酸化鉄１重量当りにカーボン
ブラツク240重量部からなる混合物40ｇを充填し
た。Comparative example: A vertical tube was placed in a graphite container similar to the above example.
Four plate-shaped molded bodies of 40 mm, width 115 mm, thickness 8 mm, and silicon dioxide content of 95% by weight were arranged at equal intervals.
The void in the container was filled with 40 g of a mixture consisting of 240 parts by weight of carbon black per 1 weight of iron dioxide.
これを電気炉内に挿入し、実施例と同じ条件下
に水素雰囲気下に加熱反応させた後、得られた反
応生成物を空気中で燃焼させ、残存炭素を燃焼除
去させて、淡緑色綿状であつて、二酸化ケイ素
4.1重量％を含む炭化ケイ素ウイスカー32.9ｇを
焼成物として得た。理論収量に対する収率は82％
であつた。 This was inserted into an electric furnace and heated to react in a hydrogen atmosphere under the same conditions as in the example, and the resulting reaction product was combusted in the air to burn off the remaining carbon and produce light green cotton. silicon dioxide
32.9 g of silicon carbide whiskers containing 4.1% by weight were obtained as a fired product. Yield is 82% of theoretical yield
It was hot.
この焼成物中をフツ酸にて洗浄した後、Ｘ線回
折した結果、β−炭化ケイ素であることが確認さ
れた。 After washing the inside of this fired product with hydrofluoric acid, it was confirmed to be β-silicon carbide by X-ray diffraction.
第１図は、ケイ素含有原料及び炭素含有原料を
充填した反応容器の一例を示す断面図である。
１……反応容器、２……ケイ素含有原料、３…
…一酸化ケイ素生成域、４……仕切り材、５……
炭素含有原料、６……炭化ケイ素生成域。
FIG. 1 is a sectional view showing an example of a reaction vessel filled with a silicon-containing raw material and a carbon-containing raw material. 1... Reaction container, 2... Silicon-containing raw material, 3...
...Silicon monoxide production area, 4...Partition material, 5...
Carbon-containing raw material, 6...Silicon carbide production area.
Claims (1)
粉末との混合物からなる一酸化ケイ素発生域と炭
素含有原料を含む炭化ケイ素生成域とを通気下に
隔離して配設し、非酸化性雰囲気下に1400〜1700
℃の温度に加熱することを特徴とする炭化ケイ素
ウイスカーの製造方法。 ２ 炭化ケイ素生成域が炭素含有原料粉末からな
ることを特徴とする特許請求の範囲第１項記載の
炭化ケイ素ウイスカーの製造方法。 ３ 非酸化性雰囲気が水素ガス雰囲気であること
を特徴とする特許請求の範囲第１項記載の炭化ケ
イ素ウイスカーの製造方法。[Scope of Claims] 1. A silicon monoxide generation area made of a mixture of metal silicon powder and silicon dioxide powder and a silicon carbide generation area containing a carbon-containing raw material are arranged in a reaction vessel in isolation under ventilation, 1400~1700 under non-oxidizing atmosphere
A method for producing silicon carbide whiskers, characterized by heating to a temperature of °C. 2. The method for producing silicon carbide whiskers according to claim 1, wherein the silicon carbide generating region is made of carbon-containing raw material powder. 3. The method for producing silicon carbide whiskers according to claim 1, wherein the non-oxidizing atmosphere is a hydrogen gas atmosphere.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61301969A JPS63156099A (en) | 1986-12-17 | 1986-12-17 | Production of silicon carbide whisker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61301969A JPS63156099A (en) | 1986-12-17 | 1986-12-17 | Production of silicon carbide whisker |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63156099A JPS63156099A (en) | 1988-06-29 |
| JPH0351680B2 true JPH0351680B2 (en) | 1991-08-07 |
Family
ID=17903308
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61301969A Granted JPS63156099A (en) | 1986-12-17 | 1986-12-17 | Production of silicon carbide whisker |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63156099A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58120599A (en) * | 1982-01-12 | 1983-07-18 | Onoda Cement Co Ltd | Production of beta-silicon carbide whisker |
-
1986
- 1986-12-17 JP JP61301969A patent/JPS63156099A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58120599A (en) * | 1982-01-12 | 1983-07-18 | Onoda Cement Co Ltd | Production of beta-silicon carbide whisker |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63156099A (en) | 1988-06-29 |
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