JPH07138100A - Sic whisker for ceramic composite reinforcement - Google Patents
Sic whisker for ceramic composite reinforcementInfo
- Publication number
- JPH07138100A JPH07138100A JP5309814A JP30981493A JPH07138100A JP H07138100 A JPH07138100 A JP H07138100A JP 5309814 A JP5309814 A JP 5309814A JP 30981493 A JP30981493 A JP 30981493A JP H07138100 A JPH07138100 A JP H07138100A
- Authority
- JP
- Japan
- Prior art keywords
- sic
- whiskers
- diameter
- sic whiskers
- rice husk
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、各種セラミックス材に
対して優れた複合強化機能を示す性状のセラミックス複
合強化用ＳｉＣウイスカーに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a SiC whisker for ceramics composite strengthening which has an excellent composite strengthening function for various ceramics materials.
【０００２】[0002]
【従来の技術】農業廃棄物として多量に副生する籾殻に
は、ＳｉＣを生成させるために必要なＳｉ成分、Ｃ成分
および触媒となるＦｅ等の金属成分を含んでいる。この
点に着目して、籾殻を珪素源原料としたＳｉＣウイスカ
ーの製造技術が数多く提案されている。これらの籾殻を
珪素源原料とする従来技術によるＳｉＣウイスカーの製
造手段は、籾殻または籾殻を炭化した籾殻炭をそのまま
原料として不活性雰囲気下で加熱処理する方法（特開昭
53−113300号公報）と、籾殻を一旦焼却して灰化物と
し、この籾殻灰に還元用の炭材を混合した原料系を不活
性雰囲気下で加熱処理する方法（特開昭57−209813号公
報、特開昭58−45195 号公報、特開昭58−45198 号公
報）に大別される。2. Description of the Related Art Rice husks, which are by-produced in large amounts as agricultural waste, contain Si components, C components, and metal components such as Fe, which are catalysts, necessary for producing SiC. Focusing on this point, many techniques for producing SiC whiskers using rice husks as a silicon source material have been proposed. A conventional method for producing SiC whiskers using these rice husks as a silicon source material is a method in which rice husks or rice husk carbon obtained by carbonizing rice husks are directly used as a raw material and subjected to heat treatment in an inert atmosphere (Japanese Patent Application Laid-Open No. Sho-200)
53-113300) and husks are once incinerated to form an ash, and a raw material system in which this husk ash is mixed with a reducing carbonaceous material is subjected to heat treatment under an inert atmosphere (JP-A-57-209813). Gazette, JP-A-58-45195 and JP-A-58-45198).
【０００３】上記の方法で生成されるＳｉＣウイスカー
は、総じて他の珪素源原料を用いて生成されたＳｉＣウ
イスカーに比べて伸直性に優れているため、各種マトリ
ック材料の複合強化材として有用視されているが、セラ
ミックスに対する複合化性能については十分な評価が得
られていない。Since the SiC whiskers produced by the above method are generally superior in straightness as compared with the SiC whiskers produced by using other silicon source materials, they are considered to be useful as a composite reinforcing material for various matric materials. However, sufficient evaluation has not been obtained regarding the composite performance with respect to ceramics.
【０００４】[0004]
【発明が解決しようとする課題】本発明者らの検討によ
ると、籾殻を珪素源原料として生成したＳｉＣウイスカ
ーが靭性改善に有効な伸直性を有しながらセラミックス
に対して十分な複合性能が発揮されない理由は、ある種
のＳｉＣウイスカーは耐熱性が低く、複合焼結時に熱変
形を生じて複合化特性を損ねるためであり、これは主に
ウイスカーを構成する結晶の微構造に起因すると推定さ
れた。According to the studies made by the present inventors, SiC whiskers produced by using rice husks as a silicon source material have sufficient composite performance with respect to ceramics while having straightness effective for improving toughness. The reason why it is not exhibited is that some SiC whiskers have low heat resistance and undergo thermal deformation during complex sintering, which impairs the compounding properties. It is presumed that this is mainly due to the microstructure of the crystals that make up the whiskers. Was done.
【０００５】籾殻原料系のＳｉＣウイスカーに関する結
晶の微構造については、既に研究報文〔Nutt,J.Am.Cera
m.Soc.vol 71,No3 P149-156(1988) 〕に発表されてお
り、この解明によると籾殻を珪素源原料として生成した
ＳｉＣウイスカーの断面は、図１に示すように中心領域
は金属不純物からなる球（主にＣａ，Ｍｎ，Ｏから構成
された直径５〜20nm程度の球) を多く含んだ中心核領域
１(core-region) が存在し、この中心領域を取り囲むよ
うに純粋なＳｉＣ領域２が形成されている。The crystal microstructure of the rice husk-based SiC whiskers has already been reported in the research paper [Nutt, J. Am. Cera].
m.Soc.vol 71, No3 P149-156 (1988)], and according to this clarification, the cross section of the SiC whiskers produced by using rice husks as a silicon source material has a metallic impurity in the central region as shown in FIG. There is a core-region containing many spheres (mainly composed of Ca, Mn, and O and having a diameter of about 5 to 20 nm), and pure SiC surrounds this core region. Region 2 is formed.
【０００６】本発明者らは前記のＳｉＣウイスカーを構
成する断面微構造と耐熱性との関係について詳細に研究
した結果、中心核領域の直径と全体のＳｉＣウイスカー
の直径との比が一定範囲にある場合には、セラミックス
に複合する際の高温焼結温度においても変形し難い十分
な耐熱性を示す事実を確認した。The present inventors have studied in detail the relationship between the cross-sectional microstructure of the SiC whiskers and the heat resistance, and as a result, the ratio of the diameter of the central core region to the diameter of the entire SiC whiskers has fallen within a certain range. In some cases, it has been confirmed that even when it is combined with ceramics, it does not easily deform even at a high temperature sintering temperature and exhibits sufficient heat resistance.
【０００７】本発明はかかる知見に基づいて開発された
もので、その目的は、各種セラミッス材に対して優れた
複合強化機能を発揮する性状のセラミックス複合強化用
ＳｉＣウイスカーを提供することにある。The present invention was developed on the basis of such findings, and an object thereof is to provide a SiC whisker for ceramics composite strengthening having a property of exhibiting an excellent composite strengthening function for various ceramic materials.
【０００８】[0008]
【課題を解決するための手段】上記の目的を達成するた
めの本発明によるセラミックス複合強化用ＳｉＣウイス
カーは、籾殻を珪素原料として生成したＳｉＣウイスカ
ーであって、金属不純物からなる球を含む中心核領域の
直径(d2)とウイスカーの直径(d1)の比(d2/d1)が０．２
〜０．７の範囲になる断面構造を有することを構成上の
特徴とする。The SiC whiskers for strengthening ceramics composite according to the present invention for achieving the above objects are SiC whiskers produced by using rice husks as a silicon raw material, and include a central core containing spheres made of metal impurities. The ratio of the area diameter (d 2 ) to the whisker diameter (d 1 ) (d 2 / d 1 ) is 0.2.
The structural feature is to have a cross-sectional structure in the range of 0.7.
【０００９】本発明を構成するＳｉＣウイスカーは、籾
殻または籾殻炭を加熱処理するか、籾殻灰と炭材の混合
物を加熱処理することにより生成されたものであり、例
えば珪石、シリカゲルあるいは有機珪素化合物等を珪素
源原料として生成されたＳｉＣウイスカーは除外され
る。The SiC whiskers constituting the present invention are produced by heating rice husk or rice husk charcoal or by heating a mixture of rice husk ash and carbonaceous material, for example, silica stone, silica gel or organic silicon compound. SiC whiskers produced by using as a silicon source material are excluded.
【００１０】ＳｉＣウイスカーの断面構造において、金
属不純物からなる球を含む中心核領域の直径は図１のｄ
2 で示され、ウイスカーの直径は図１のｄ1 で示される
長さである。これら直径の比(d2/d1) が０．２未満であ
ったり、中心核領域が存在しない中空構造であると生成
物中のＳｉＯ2 成分が多く残留してＳｉＣウイスカーの
歩留りが低下するうえ、熱処理により容易に粒状化する
ようになる。また、前記比が０．７を越えると耐熱性が
減退して焼結温度で変形を生じるため、セラミックスに
対する十分な複合性能が付与されなくなる。In the cross-sectional structure of the SiC whiskers, the diameter of the central core region including the spheres made of metal impurities is d in FIG.
2 , the diameter of the whiskers is the length indicated by d 1 in FIG. If the ratio of these diameters (d 2 / d 1 ) is less than 0.2, or if the hollow structure does not have a central core region, a large amount of SiO 2 component remains in the product and the yield of SiC whiskers decreases. In addition, the heat treatment facilitates granulation. On the other hand, if the ratio exceeds 0.7, heat resistance deteriorates and deformation occurs at the sintering temperature, so that sufficient composite performance for ceramics cannot be imparted.
【００１１】本発明のＳｉＣウイスカーは、上記した特
定の断面構造のほかに結晶のα度が２０％以上であるこ
とが好ましい性状となる。該α度は、ＳｉＣウイスカー
の長手方向（β−ＳｉＣ＜１１１＞方向）に垂直な面に
存在する積層欠陥密度の指標となるもので、下式によっ
て定義される。 上式において、Ｈ1 は粉末Ｘ線回折プロファイルにおけ
るＣｕＫαを線源としたときの２θが３３．５deg のと
きに現出する回折強度、Ｈ2 は同２θが３５．６deg の
ときに現出する回折強度である。The SiC whiskers of the present invention preferably have a crystal α degree of 20% or more in addition to the above-described specific cross-sectional structure. The α degree is an index of the stacking fault density existing in a plane perpendicular to the longitudinal direction of the SiC whiskers (β-SiC <111> direction), and is defined by the following formula. In the above equation, H 1 is the diffraction intensity that appears when 2θ is 33.5 deg when CuKα is the radiation source in the powder X-ray diffraction profile, and H 2 appears when the same 2θ is 35.6 deg. This is the diffraction intensity.
【００１２】このα度はＳｉＣウイスカーの形状と相関
があり、現象的にα度が２０％以上である場合には積層
欠陥が多くなって良好な伸直性を示す。したがって、複
合強化したセラミックスの破壊時にプルアウト現象を誘
発し、材料の破壊靱性値を向上させるために有効に機能
する。This α degree correlates with the shape of the SiC whiskers. When the α degree is 20% or more, the number of stacking faults increases and good straightness is exhibited. Therefore, when the composite-reinforced ceramics is broken, the pull-out phenomenon is induced, and it effectively functions to improve the fracture toughness value of the material.
【００１３】上記の性状を備える本発明のＳｉＣウイス
カーは、次のようにして製造することができる。籾殻を
そのまま、籾殻を非酸化性雰囲気下で６００℃以上の温
度で加熱処理して炭化させた籾殻炭、もしくは籾殻を大
気中で６００℃以上の温度で焼却して残留した籾殻灰と
炭材との混合物を原料とする。混合原料系に用いる炭材
としてはカーボンブラックが好適で、特に窒素吸着比表
面積が４０m2/g以上で、ＤＢＰ吸油量が５０ml/100g 以
上の粒子性状を備えるファーネスブラックが好ましく用
いられる。また、炭材の配合比率は籾殻灰１００重量部
に対し７０〜４００重量部の範囲に設定する。これら原
料は黒鉛製の密閉容器に充填したのち、Ｎ2 、Ａｒなど
の不活性雰囲気に保持された加熱炉中で加熱処理する。The SiC whisker of the present invention having the above properties can be manufactured as follows. Rice husks as they are, the rice husks are carbonized by heating the rice husks at a temperature of 600 ° C or higher in a non-oxidizing atmosphere, or the rice husk ash and carbonaceous materials left after burning the rice husks at a temperature of 600 ° C or higher in the atmosphere. The mixture is used as a raw material. Carbon black is suitable as the carbonaceous material used in the mixed raw material system, and in particular, furnace black having a nitrogen adsorption specific surface area of 40 m 2 / g or more and a DBP oil absorption of 50 ml / 100 g or more is preferably used. Further, the blending ratio of the carbonaceous material is set in the range of 70 to 400 parts by weight with respect to 100 parts by weight of rice husk ash. These raw materials are filled in a graphite airtight container and then heat-treated in a heating furnace kept in an inert atmosphere of N 2 , Ar or the like.
【００１４】加熱処理の過程で容器内部の原料充填空隙
にＳｉＣウイスカーが生成するが、加熱条件として９０
０℃以上の昇温速度を２〜５℃／分の範囲とし、加熱温
度を籾殻または籾殻炭を原料とする場合には１５００〜
１８００℃に、籾殻灰と炭材の混合物を原料とする場合
には１６００〜１９００℃に設定することにより本発明
で特定された断面構造およびα度を備えるＳｉＣウイス
カーが生成される。昇温速度が２℃／分を下廻ると、Ｓ
ｉＣウイスカー断面における中心核領域の直径(d2)とウ
イスカー直径(d1)の比(d2/d1) が０．７を越えるように
なり、５℃／分を上廻る場合にはα度が２０％未満に低
下し、同時にＳｉＣウイスカーの生成歩留りも減退する
傾向を示す。また、加熱温度を前記範囲より低くすると
ＳｉＣウイスカーが生成しなかったり、ＳｉＯ2 成分の
残留率が高く、中心核領域のない中空の断面構造のＳｉ
Ｃウイスカーが生成するようになる。一方、加熱温度が
前記範囲を越えると生成ＳｉＣウイスカーのα度が著し
く低下し、性状も径太化、粒状化が起こって粉末含有比
率が増大する。SiC whiskers are generated in the material-filled voids inside the container during the heat treatment process.
When the temperature rising rate of 0 ° C. or higher is set to a range of 2 to 5 ° C./min and the heating temperature is rice husk or rice husk charcoal as a raw material, 1500 to 500
When a mixture of rice husk ash and carbonaceous material is used as a raw material, the temperature is set to 1600 to 1900 ° C., whereby SiC whiskers having the cross-sectional structure and α degree specified in the present invention are produced. If the temperature rising rate is below 2 ° C / min, S
The ratio (d 2 / d 1 ) of the diameter (d 2 ) of the central core region to the diameter of the whiskers (d 1 ) in the cross section of the iC whiskers exceeds 0.7, and α exceeds 5 ° C / min. And the yield of SiC whiskers tends to decrease at the same time. When the heating temperature is lower than the above range, SiC whiskers are not generated, the residual ratio of SiO 2 component is high, and Si having a hollow cross-sectional structure without a central core region is used.
C whiskers will be generated. On the other hand, when the heating temperature exceeds the above range, the α degree of the produced SiC whiskers is remarkably reduced, and the properties also increase in diameter and granulation, increasing the powder content ratio.
【００１５】加熱処理後の生成物は、ついで大気中で６
００℃以上の温度で加熱処理して残留する炭素成分を焼
却除去し、必要に応じて機器分離精製および弗化水素酸
による洗浄処理を施して目的のＳｉＣウイスカーを得
る。The product after the heat treatment is then subjected to 6 in the atmosphere.
The remaining carbon components are incinerated and removed by heating at a temperature of 00 ° C. or higher, and if necessary, purification by device separation and washing with hydrofluoric acid are performed to obtain the desired SiC whiskers.
【００１６】[0016]
【作用】籾殻を珪素源原料として生成され、金属不純物
からなる球を含む中心核領域の直径(d2)とウイスカー直
径(d1)の比(d2/d1) が０．２〜０．７の断面構造を有す
る本発明のＳｉＣウイスカーは、耐熱性が高いためセラ
ミックス材料と焼結する際の高温で変形を生じることが
ない。したがって、これを分散させて複合焼結したセラ
ミックス複合強化材には優れた強度性能が付与される。[Function] The ratio (d 2 / d 1 ) of the diameter (d 2 ) and the diameter of the whiskers (d 1 ) of the central core region, which is produced from rice husks as a silicon source material and contains spheres made of metal impurities, is 0.2 to 0. Since the SiC whiskers of the present invention having a cross-sectional structure of 0.7 have high heat resistance, they do not deform at a high temperature during sintering with a ceramic material. Therefore, excellent strength performance is imparted to the ceramic composite reinforcement material obtained by dispersing and sintering the composite.
【００１７】また、籾殻原料系のＳｉＣウイスカーは本
来的に良好な伸直性を示すが、結晶系のα度を２０％以
上にすると一層、針状結晶の伸直性が向上し、複合化し
たセラミックス材料の破壊靭性を増大させることが可能
となる。Although SiC whiskers of rice husk raw material originally show good straightness, the straightness of needle-like crystals is further improved by increasing the α-degree of the crystal system to 20% or more to form a composite. The fracture toughness of the ceramic material can be increased.
【００１８】[0018]
【実施例】以下、本発明の実施例を比較例と対比しなが
ら具体的に説明する。EXAMPLES Examples of the present invention will be specifically described below in comparison with comparative examples.
【００１９】実施例１〜７、比較例１〜６ 籾殻を蓋付きの黒鉛容器に充填し、Ｎ2 雰囲気に保持さ
れた電気炉に入れて８００℃の温度で９０分間加熱処理
して炭化した。得られた籾殻炭を再び同様の黒鉛容器に
軽く充填して高周波加熱炉にセットし、所定の昇温速度
(900℃以上) により１５５０〜１９００℃の各温度に設
定して９０分間保持してＳｉＣウイスカーを生成させ
た。処理後の容器内部は、籾殻表面に緑白色のＳｉＣウ
イスカーとＳｉＣ粉末が生成付着していた。ついで、生
成物を大気中で６００℃の温度により加熱処理して残留
する炭素成分を焼却除去したのち、湿式サイクロンおよ
び水篩分級処理により粉末を分離し、５％濃度の弗化水
素酸により洗浄処理した。Examples 1 to 7 and Comparative Examples 1 to 6 Rice husks were filled in a graphite container with a lid, placed in an electric furnace maintained in an N 2 atmosphere, and heat-treated at 800 ° C. for 90 minutes for carbonization. . The obtained rice husk charcoal is lightly charged again in the same graphite container and set in a high-frequency heating furnace, and the predetermined heating rate is set.
(900 ° C. or higher), the temperature was set to 1550 to 1900 ° C. and held for 90 minutes to generate SiC whiskers. Inside the container after the treatment, green-white SiC whiskers and SiC powder were formed and adhered to the surface of the rice husk. Then, the product is heat-treated in the air at a temperature of 600 ° C. to remove the remaining carbon components by incineration, and then the powder is separated by a wet cyclone and a water sieving process and washed with 5% hydrofluoric acid. Processed.
【００２０】このようにして得られたＳｉＣウイスカー
のアスペクト性状は、直径０．１〜０．５μm 、長さ２
０〜３０μm であった。各ＳｉＣウイスカーの生成収
率、断面構造における金属不純物からなる球を含む中心
核領域の直径(d2)とウイスカー直径(d1)の比(d2/d1) お
よびα度を測定し、その結果を生成時の温度条件と対比
させて表１に示した。なお、断面構造の測定はＳｉＣウ
イスカー１００本につき透過型電子顕微鏡の観察でおこ
ない、その平均値として表示した。The SiC whiskers thus obtained have an aspect ratio of 0.1 to 0.5 μm in diameter and 2 in length.
It was 0 to 30 μm. Production yield of the SiC whiskers, and measuring the ratio (d 2 / d 1) and α of the diameter of the central core region containing a ball made of metal impurities (d 2) and whiskers diameter (d 1) in the sectional structure, The results are shown in Table 1 in comparison with the temperature conditions at the time of production. The cross-sectional structure was measured by observing 100 SiC whiskers with a transmission electron microscope and displayed as an average value.
【００２１】[0021]
【表１】 [Table 1]
【００２２】上記の生成ＳｉＣウイスカーを黒鉛容器に
充填し、Ａｒガス雰囲気に保持された加熱炉中で１８０
０℃の温度で２０分間加熱処理し、処理後の形状変化を
電子顕微鏡で観察した。この耐熱テストの結果を表２に
示した。The resulting SiC whiskers were filled in a graphite container and heated in a heating furnace kept in an Ar gas atmosphere for 180 hours.
Heat treatment was performed for 20 minutes at a temperature of 0 ° C., and the change in shape after the treatment was observed with an electron microscope. The results of this heat resistance test are shown in Table 2.
【００２３】次に、平均粒子径０．４μm のＡｌ2 Ｏ3
粉末〔住友化学（株）製、ＡＫＰ−３０〕をマトリック
スとし、これに各ＳｉＣウイスカーを体積含有率２５ v
ol％の比率になるように配合してボールミルに入れ、エ
タノールを分散媒として十分に撹拌し湿式混合した。混
合スラリーを加熱してエタノール分散媒を蒸発除去した
のち、モールドに充填して１５０kg/cm2の圧力により予
備成形し、引き続き冷間静水圧成形装置により２ ton/c
m2で成形して円盤状の成形体を得た。Next, Al 2 O 3 having an average particle size of 0.4 μm is used.
A powder [AKP-30 manufactured by Sumitomo Chemical Co., Ltd.] was used as a matrix, and each SiC whisker had a volume content of 25 v.
The mixture was blended so as to have an ol% ratio, put in a ball mill, and sufficiently mixed by wet mixing with ethanol as a dispersion medium. After heating the mixed slurry to remove the ethanol dispersion medium by evaporation, it is filled in a mold and preformed at a pressure of 150 kg / cm 2 , followed by 2 ton / c by a cold isostatic press.
Molding was performed at m 2 to obtain a disk-shaped molded body.
【００２４】ついで、成形体を真空雰囲気下で温度１６
００℃、圧力５００kg/cm2の条件でホットプレス焼結を
おこない、直径５０mm、厚さ１５mmのＳｉＣウイスカー
強化アルミナ複合材を得た。得られた各複合材について
曲げ強度を測定し、その結果を表２に併載した。なお、
曲げ強度はＪＩＳ−１６０１による３点曲げ試験法によ
り測定した。Then, the molded body is heated in a vacuum atmosphere at a temperature of 16
Hot press sintering was performed under the conditions of 00 ° C. and a pressure of 500 kg / cm 2 to obtain a SiC whisker reinforced alumina composite material having a diameter of 50 mm and a thickness of 15 mm. The bending strength of each of the obtained composite materials was measured, and the results are also shown in Table 2. In addition,
The bending strength was measured by the three-point bending test method according to JIS-1601.
【００２５】[0025]
【表２】 [Table 2]
【００２６】実施例８〜９、比較例７〜８ 籾殻を大気中で燃焼処理して残留した籾殻灰を珪素源原
料とし、その１００重量部に対し炭材として窒素吸着比
表面積９９m2/g、ＤＢＰ吸油量１２９ml/100gのカーボ
ンブラック〔東海カーボン（株）製、シースト５Ｈ〕を
２４０重量部配合し、ジューサーミキサーにより均一に
混合した。この混合原料を蓋付き黒鉛容器に軽く充填
し、Ｎ2 ガス雰囲気に保持された高周波炉にセットして
３℃／分の昇温速度(900℃以上）で１５５０〜１９５０
℃の各設定温度に保持して９０分間加熱処理を施した。
生成物を大気中で６００℃の温度に加熱して残留する炭
材成分を酸化除去し、５％濃度の弗化水素酸溶液により
洗浄した。得られたＳｉＣウイスカーの性状を表３に示
した。Examples 8 to 9 and Comparative Examples 7 to 8 Rice husk ash remaining by burning rice husks in the atmosphere was used as a silicon source material, and 100 parts by weight of the rice husk ash was used as a carbonaceous material and a nitrogen adsorption specific surface area of 99 m 2 / g. , 240 parts by weight of carbon black having a DBP oil absorption of 129 ml / 100 g [SEAST 5H manufactured by Tokai Carbon Co., Ltd.] was mixed and uniformly mixed with a juicer mixer. This mixed raw material was lightly filled in a graphite container with a lid, set in a high-frequency furnace maintained in an N 2 gas atmosphere, and heated at a rate of 3 ° C./min (900 ° C. or higher) from 1550 to 1950.
The heat treatment was performed for 90 minutes while maintaining each set temperature of ° C.
The product was heated to a temperature of 600 ° C. in the atmosphere to oxidize and remove the remaining carbonaceous material component, and washed with a 5% hydrofluoric acid solution. Table 3 shows the properties of the obtained SiC whiskers.
【００２７】[0027]
【表３】 [Table 3]
【００２８】ついで、実施例１と同様に耐熱テストおよ
びＡｌ2 Ｏ3 粉末マトリックスとの複合材強度を測定
し、その結果を表４に示した。Then, the heat resistance test and the strength of the composite material with the Al 2 O 3 powder matrix were measured in the same manner as in Example 1, and the results are shown in Table 4.
【００２９】[0029]
【表４】 [Table 4]
【００３０】比較例９ 籾殻灰の代わりに、ＳｉＯ2 含有率９９．５％のシリカ
ゲル粉末（１５０メッシュ以下）に予めＣｏＣｌ2 ・６
Ｈ2 Ｏを添加（珪素源原料に対し３．７重量％）したも
のを珪素源原料とし、その他の条件は実施例８と同一に
してＳｉＣウイスカーを得た。生成したＳｉＣウイスカ
ーは、直径が０．５mm、長さ３０μm であったが、α度
は２％で断面構造には中心核領域は観察されなかった。
また、このＳｉＣウイスカーを用いて実施例１と同様に
して複合化したアルミナ複合材の曲げ強度は６８０MPa
であった。Comparative Example 9 Instead of chaff ash, silica gel powder having a SiO 2 content of 99.5% (150 mesh or less) was previously added to CoCl 2 .6.
A SiC whisker was obtained under the same conditions as in Example 8 except that H 2 O was added (3.7% by weight to the silicon source material) as the silicon source material. The produced SiC whiskers had a diameter of 0.5 mm and a length of 30 μm, but α degree was 2%, and no central nucleus region was observed in the cross-sectional structure.
Further, the bending strength of the alumina composite material composited using this SiC whisker in the same manner as in Example 1 is 680 MPa.
Met.
【００３１】[0031]
【発明の効果】以上のとおり、本発明によれば籾殻を珪
素源原料として生成した特定性状を備え、各種セラミッ
クスに複合化して優れた特性改善を図ることが可能なセ
ラミックス複合強化用ＳｉＣウイスカーを提供すること
ができる。したがって、高温耐蝕性構造部材を対象とす
るセラミックス類の複合強化材として有用である。As described above, according to the present invention, there is provided a SiC whisker for strengthening ceramics composite, which has a specific property that rice husks are produced as a silicon source material and which can be composited into various ceramics to improve the properties excellently. Can be provided. Therefore, it is useful as a composite reinforcing material of ceramics for high temperature corrosion resistant structural members.
【図１】本発明に係るＳｉＣウイスカーの断面構造を模
式的に示した説明図である。FIG. 1 is an explanatory view schematically showing a cross-sectional structure of a SiC whisker according to the present invention.
１ 中心核領域 ２ ＳｉＣ領域 1 central nucleus region 2 SiC region
フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｃ０４Ｂ 35/80 Ｃ３０Ｂ 29/36 Ａ 8216−4Ｇ Continuation of front page (51) Int.Cl. 6 Identification number Office reference number FI technical display location C04B 35/80 C30B 29/36 A 8216-4G
Claims (3)
ウイスカーであって、金属不純物からなる球を含む中心
核領域の直径(d2)とウイスカーの直径(d1)の比(d2/d1)
が０．２〜０．７の範囲にある断面構造を有することを
特徴とするセラミックス複合強化用ＳｉＣウイスカー。1. SiC produced by using rice husks as a silicon source material
The ratio (d 2 / d 1 ) of the diameter (d 2 ) of the central core region containing the spheres of metallic impurities and the diameter (d 1 ) of the whiskers.
Has a cross-sectional structure in the range of 0.2 to 0.7. A SiC composite strengthening SiC whisker.
ある請求項１記載のセラミックス複合強化用ＳｉＣウイ
スカー。2. The SiC whisker for ceramic composite strengthening according to claim 1, wherein the α degree of the SiC whisker is 20% or more.
を加熱処理するか、籾殻灰と炭材の混合物を加熱処理す
ることにより生成されたものである請求項１又は２記載
のセラミックス複合強化用ＳｉＣウイスカー。3. The SiC for strengthening ceramic composite according to claim 1, wherein the SiC whiskers are produced by heat-treating rice husk or rice husk charcoal or a mixture of rice husk ash and carbonaceous material. Whiskers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5309814A JPH07138100A (en) | 1993-11-15 | 1993-11-15 | Sic whisker for ceramic composite reinforcement |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5309814A JPH07138100A (en) | 1993-11-15 | 1993-11-15 | Sic whisker for ceramic composite reinforcement |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07138100A true JPH07138100A (en) | 1995-05-30 |
Family
ID=17997573
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5309814A Pending JPH07138100A (en) | 1993-11-15 | 1993-11-15 | Sic whisker for ceramic composite reinforcement |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07138100A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100348547C (en) * | 2005-12-26 | 2007-11-14 | 西北工业大学 | Process for preparing silicon carbide coating on surface of carbon/carbon composite material |
| JP2014040354A (en) * | 2012-08-23 | 2014-03-06 | Noritake Co Ltd | Green sheet for forming porous electrode, auxiliary sheet for baking, and utilization of the same |
-
1993
- 1993-11-15 JP JP5309814A patent/JPH07138100A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100348547C (en) * | 2005-12-26 | 2007-11-14 | 西北工业大学 | Process for preparing silicon carbide coating on surface of carbon/carbon composite material |
| JP2014040354A (en) * | 2012-08-23 | 2014-03-06 | Noritake Co Ltd | Green sheet for forming porous electrode, auxiliary sheet for baking, and utilization of the same |
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