JPH04175264A - Raw material powder of mullite based sintered compact and production of mullite based sintered compact - Google Patents
Raw material powder of mullite based sintered compact and production of mullite based sintered compactInfo
- Publication number
- JPH04175264A JPH04175264A JP2325926A JP32592690A JPH04175264A JP H04175264 A JPH04175264 A JP H04175264A JP 2325926 A JP2325926 A JP 2325926A JP 32592690 A JP32592690 A JP 32592690A JP H04175264 A JPH04175264 A JP H04175264A
- Authority
- JP
- Japan
- Prior art keywords
- mullite
- powder
- less
- raw material
- strength
- 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
- 239000000843 powder Substances 0.000 title claims abstract description 91
- 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 title claims abstract description 90
- 229910052863 mullite Inorganic materials 0.000 title claims abstract description 90
- 239000002994 raw material Substances 0.000 title claims abstract description 24
- 238000004519 manufacturing process Methods 0.000 title claims description 12
- 239000002245 particle Substances 0.000 claims abstract description 26
- 239000000203 mixture Substances 0.000 claims abstract description 15
- 239000013078 crystal Substances 0.000 claims abstract description 10
- 239000012535 impurity Substances 0.000 claims description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 37
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract description 20
- 239000000377 silicon dioxide Substances 0.000 abstract description 17
- 229910052681 coesite Inorganic materials 0.000 abstract description 7
- 229910052906 cristobalite Inorganic materials 0.000 abstract description 7
- 235000012239 silicon dioxide Nutrition 0.000 abstract description 7
- 229910052682 stishovite Inorganic materials 0.000 abstract description 7
- 229910052905 tridymite Inorganic materials 0.000 abstract description 7
- 229910052593 corundum Inorganic materials 0.000 abstract description 6
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 abstract description 6
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract description 6
- 239000006185 dispersion Substances 0.000 abstract description 3
- 239000007858 starting material Substances 0.000 description 17
- 238000000034 method Methods 0.000 description 12
- 238000010304 firing Methods 0.000 description 8
- 230000007423 decrease Effects 0.000 description 5
- BYFGZMCJNACEKR-UHFFFAOYSA-N aluminium(i) oxide Chemical compound [Al]O[Al] BYFGZMCJNACEKR-UHFFFAOYSA-N 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 239000004065 semiconductor Substances 0.000 description 4
- 238000005507 spraying Methods 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 239000005995 Aluminium silicate Substances 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 235000012211 aluminium silicate Nutrition 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- JBRZTFJDHDCESZ-UHFFFAOYSA-N AsGa Chemical compound [As]#[Ga] JBRZTFJDHDCESZ-UHFFFAOYSA-N 0.000 description 1
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 1
- 150000001342 alkaline earth metals Chemical class 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 239000002734 clay mineral Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 229910021485 fumed silica Inorganic materials 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000012798 spherical particle Substances 0.000 description 1
- 238000001694 spray drying Methods 0.000 description 1
- -1 that is Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
Abstract
Description
本発明は、例えば高温耐熱構造用セラミックスや集積回
路基板（絶縁セラミックス基板）として利用できるムラ
イト質焼結体の原料粉末及びムライト質焼結体の製造方
法に関するものである。The present invention relates to a raw material powder for a mullite sintered body that can be used, for example, as ceramics for high-temperature heat-resistant structures or integrated circuit boards (insulating ceramic substrates), and a method for producing the mullite sintered body.
ムライト（３Ａ］、０３ ・２ＳｊＯ２）質焼結体は、
高温における強度低下が小さ（、高温構造用セラミック
ス材料として、又、アルミナセラミックスに比べ誘電率
が低く、熱膨張率係数もシリコン半導体素子やガリウム
ーヒ素半導体素子に近い為、集積回路用絶縁性基板材料
としても注目を浴びている。
ところで、ムライト質焼結体の製造方法は、出発原料の
種類により次の三つに大別できる。
■ カオリンなどの粘土ＦＬ物を出発原料とする方法
■ アルミナ（Ａ １２ Ｃ１＋ ）粉末とシリカ（Ｓ
ｉ０２）粉末を出発原料とする方法
■ 電融法により合成したムライトを粉砕し、この粉末
を出発原料とする方法The mullite (3A), 03 ・2SjO2) sintered body is
Small strength loss at high temperatures (as a ceramic material for high-temperature structures, and has a lower dielectric constant than alumina ceramics and a coefficient of thermal expansion close to that of silicon semiconductor elements and gallium-arsenide semiconductor elements, so it is suitable as an insulating substrate material for integrated circuits. By the way, methods for producing mullite sintered bodies can be roughly divided into the following three types depending on the type of starting material: ■ A method using a clay FL material such as kaolin as a starting material ■ A method using alumina ( A 12 C1+ ) powder and silica (S
i02) Method using powder as starting material■ Method using pulverized mullite synthesized by electrofusion method and using this powder as starting material
しかしながら、上記■のカオリンなどの粘土鉱物を出発
原料とする製造方法により得られるムライト質焼結体は
、不純物が多く、高温における強度低下が大きく、高温
構造用セラミックス材料としては利用できない。
又、α線の放射量が多い為、半導体素子の集積回路用絶
縁性基板材料として用いた場合には、半導体素子に誤動
作を起こさせる恐れがある。
■のＡ ｌ ｚ Ｏｘ粉末とＳｉＯ□粉末を出発原料と
する製造方法では、原料粉末を均一に混合するのが難し
く、焼結体組織が不均一になりやすく、又、焼結しにく
いため充分な強度をもったムライト質焼結体が得られに
くい。さらには、微粉末のＡｌ２Ｏ．粉末及びＳｉＯ□
粉末を出発原料とする場合、成形性が悪く、焼成収縮も
バラツキ、製造されたムライト焼結体の形状及び寸法の
安定生が悪いなどの欠点もある。
■の電融法により合成したムライトを粉砕した粉末を出
発原料とする製造方法では、高純度ではあるが、焼結し
にくい。
この為、微量のアルカリ金属、アルカリ土類金属等を添
加して焼結時に融液を生ぜしめ、焼結を促進させる方法
が試みられている。しかしながら、この方法で製造され
たムライト質セラミックスは、焼結体内部に２０μｍを
越える大きな気孔が形成されやすく、強度のバラツキが
大きく、又、高温での強度低下も著しいという欠点があ
る。
本発明の目的は、強度が充分に大きく、しかもバラツキ
は少なく、高温での強度低下の小さいムライト質焼結体
を容易に製造する技術を提供することである。However, the mullite sintered body obtained by the above manufacturing method using clay minerals such as kaolin as a starting material contains many impurities and has a large decrease in strength at high temperatures, so it cannot be used as a ceramic material for high-temperature structures. Furthermore, since the amount of alpha rays emitted is large, when used as an insulating substrate material for an integrated circuit of a semiconductor device, there is a risk that the semiconductor device may malfunction. In the manufacturing method using A lz Ox powder and SiO It is difficult to obtain a mullite sintered body with sufficient strength. Furthermore, fine powder Al2O. Powder and SiO□
When powder is used as a starting material, there are disadvantages such as poor moldability, variable firing shrinkage, and poor stability in shape and dimension of the produced mullite sintered body. In the manufacturing method (2), which uses as a starting material a powder obtained by pulverizing mullite synthesized by the electrofusion method, although the purity is high, it is difficult to sinter. For this reason, attempts have been made to add trace amounts of alkali metals, alkaline earth metals, etc. to produce a melt during sintering to accelerate sintering. However, the mullite ceramics produced by this method have the disadvantage that large pores exceeding 20 μm are likely to be formed inside the sintered body, the strength varies widely, and the strength decreases significantly at high temperatures. An object of the present invention is to provide a technique for easily manufacturing a mullite sintered body having sufficiently high strength, less variation, and less loss of strength at high temperatures.
本発明者は、高純度のアルミナゾルとシリカゾルを均質
に混合後、５００°Ｃ−１６００°Ｃの温度にて噴霧し
ながら焼成して種々の組成をもったムライト賞球状粉末
を合成し、このムライト質球状粉末単独を原料粉末とし
た場合、又、このムライト賞球状粉末にアルミナ粉末、
シリカ粉末及びムライト賞非球状粉末を添加したものを
原料粉末とした場合において、得られるムライト質焼結
体の強度が充分大きく、かつ、バラツキが少なく、しか
も高温での強度低下が小さいムライト質焼結体を簡単に
製造できる方法を鋭意研究した。
この結果、アルミナゾルとシリカゾルの混合物を噴霧す
ると球状粉末となるが、噴霧時の焼成温度が低いと、非
晶質の集合体で、比表面積も大きい為、成形性が悪く、
このようなものを出発原料としてムライト質焼結体を製
造した場合には、前配本発明の目的とするようなムライ
ト質焼結体は得られにくいことが判って来た。
すなわち、上記のような粉末を出発原料とした場合、成
形密度が低く、焼成収縮が大きく、安定しない為、焼成
中に割れが発生したり、焼結後の形状、寸法に大きなバ
ラツキが出たのである。
又、アルミナゾルとシリカゾルの混合物の噴霧時の焼成
温度を上げていくと、球状粉末は比表面積が象、激に小
さくなり、非晶質からムライトの結晶が生成されてくる
。さらに、噴霧時の焼成温度を上げていくと、ムライト
結晶の結晶子の大きさが微細なものから大きなものへと
変化していくことも判って来た。
これらの知見を基にして更なる研究が鋭意押し進められ
て行った結果、上記本発明の目的は、ムライト質粉末で
あり、このムライト質粉末のムライト結晶子径が２００
ｎｍ以下であって、Ａｌ２Ｏ、／ＳｉＯ□の重量比が４
０／６０〜８０／２０で、平均粒径が１０μｍ以下の球
状のものであることを特徴とするムライト質焼結体の原
料粉末によって達成されることが判明した。
又、ムライト結晶子径が２００ｎｍ以下であって、Ａ１
□Ｏ，／Ｓｉ○２の重量比が４０／６０〜８０／２０で
、平均粒径が１０μｍ以下の球状のムライト質粉末と、
ムライト結晶子径が２００ｎｍ以下であって、Ａ ｌ
ｔ ｏｘ ／Ｓ ｉ ０２の重量比が４０／６０〜８０
／２０で、平均粒径が１０μｍ以下の非球状のムライト
質粉末とを含み、前記球状のムライト質粉末１００重量
部に対して前記非球状のムライト質粉末が８０重量部以
下であることを特徴とするムライト質焼結体の原料粉末
によって達成されることが判明した。
又、Ａｌ２Ｏ３及びＳｉＯ２以外の不純物が０゜５重量
％以下で、Ａ １２０３ ／Ｓ ｉ Ｏｚの重量比が４
０／６０〜８０／２０の範囲内の値であって、結晶子の
大きさが２００ｎｍ以下のムライト結晶相を含む平均粒
径１０μｍ以下のムライト質球状粉末を原料組成とし、
このムライト質球状粉末を含む原料を成形、焼成するこ
とを特徴とするムライト質焼結体の製造方法によって達
成されることが判明した。
又、Ａ Ｉ ２０ｆｆ及びＳｉＯ□以外の不純物が０゜
５重量％以下で、結晶子の大きさが２００ｎｍ以下のム
ライト結晶相を含む平均粒径１０μｍ以下のムライト質
球状粉末１００重量部と、平均粒径が５μｍ以下のムラ
イト質非球状粉末、平均粒径が５μｍ以下のＡ Ｉ ２
０３粉末及び平均粒径が５μｍ以下の５ｉＯｚ粉末の群
の中から選ばれる少なくとも一種以上の粉末が合計８０
重量部以下とを含み、これらの原料組成におけるＡｌ２
Ｏ３／Ｓｉ○２の重量比が４０／６０〜８０／２０の範
囲内の値となるよう調整されてなるものを原料組成とし
、このムライト質球状粉末を含む原料を成形、焼成する
ことを特徴とするムライト質焼結体の製造方法によって
達成されることが判明した。
上記ムライト質焼結体の製造方法において、出発原料と
なるムライト賞球状粉末のアルミナ及びシリカ以外の成
分、すなわち不純物は０．５重量％まで許される。尚、
高温強度を重視する用途では、不純物は０．３重量％以
下、より望ましくは０．１重量％以下であることが好ま
しい。すなわち、不純物が多いと高温における強度低下
が大きくなり、特に０．５重量％を越えて多くなりすぎ
ると、高温における強度低下が著しく、内部に２０μｍ
を越える気孔が出来やすく、強度のバラツキも大きくな
る。
出発原料のアルミナ対シリカの重量比は４０対６０〜８
０対２０の範囲内のものであるが、高温における強度を
重視する場合には、シリカの割合を減少させた方が好ま
しく、すなわち６５対３５〜８０対２０、より望ましく
は７０対３０〜８０対２０であることが好ましい。
出発原料のムライト質球状粉末のムライト結晶子の大き
さは２００ｎｍ以下、好ましくは１１００ｎ以下で、ム
ライト結晶子の結晶相が含まれていることが必要である
が、ガラス相又はその他の結晶相を含んでいても良い。
すなわち、ムライト質球状粉末粒子中のムライト結晶子
の大きさが２００ｎｍを越えると、焼結しにくくなり、
充分な強度を持った焼結体が製造できにくくなる。
又、出発原料のムライト質球状粉末の平均粒径が１０μ
ｍを越えて大きくなり過ぎた場合には、焼結しにくく、
充分な強度をもった焼結体が製造されにくいことから、
平均粒径が１０μｍ以下であることが大事であり、５１
ｍ以下のものが好ましい。特に、０．３〜５μｍのもの
が好ましい。
出発原料としてＡｌ２Ｏ３及びＳｉＯ２以外の成分が０
．５重量％以下で、結晶子の大きさが２００ｎｍ以下の
ムライト結晶相を含む平均粒径１０μｍ以下のムライト
質球状粉末の他に、ムライト質非球状粉末、Ａｌ２Ｏ３
粉末及び５ｉＣ）ｚ粉末の群の中から選ばれる少なくと
も一種以上の粉末が用いられる場合には、これらの原料
組成におけるＡ１２０１対ＳｉＯ２の重量組成比が４０
対６０〜８０対２０の範囲内の値となるよう調整されな
ければならない。
尚、アルミナ対シリカの重量比は６５対３５〜８０対２
０、より望ましくは７０対３０〜８０対２０であること
が好ましい。
ムライト質非球状粉末、へ１□０３粉末及びＳｌＯ□粉
末は、平均粒径が５μｍ以下のものであることが好まし
く、より好ましくは０．３〜３μｍのものである。すな
わち、平均粒径が大きくなると焼結しにくく、一方、平
均粒径が小さくなりすぎると成形性が悪（なり、焼結体
の形状及び寸法の安定性が悪くなることから、平均粒径
が５μｍ以下、好ましくは０． ３〜３μｍのものであ
る。
又、アルミナ粉末、シリカ粉末及びムライト非球状粉末
の添加割合がムライ）１球状粉末１００重量部に対し８
０重量部を越えて多くなりすぎると、成形性、焼結性が
悪くなり、良好なムライト質焼結体が製造しにくくなる
ことから、ムライト質球状粉末１００重量部に対して平
均粒径が５ａｍ以下のムライト質非球状粉末、平均粒径
が５μｍ以下のＡ ｌ ２０ｓ粉末及び平均粒径が５μ
ｍ以下のＳｉｎ、粉末の群の中から選ばれる少なくとも
一種以上の粉末が合計８０重量部以下であることが好ま
しい。
尚、上記のようなムライト賞粉末は、ヘーマイトゾルと
シリカゾルとを所定の割合で混合し、ゲル化し、仮焼す
ることで得られる。
ヘーマイトゾルとしては、γ−Ａ Ｉ ｚ Ｏｚ ヤヘ
ーマイ） （Ａ１００Ｈ）の水分散液を加熱しながら硝
酸、塩酸などの無機酸や酢酸、ギ酸などの有機酸を加え
、解膠することによって得られたものがある。
シリカゾルとしては、シリカ微粒子、例えば湿式法で製
造されるホワイトカーボンや乾式法のヒユームドシリカ
を水中に分散させたコロイド水溶液がある。
出発原料として用いられるアルミナ粉末、シリカ粉末及
びムライト質非球状粉末は高純度のものが好ましく、出
発原料として用いる混合物の不純物（最終）の量は０．
５％以下、好ましくは０゜３％以下である。
又、ムライト質非球状粉末は電融法によって合成したム
ライトの粉砕品であるとか、ムライト質球状粉末を粉砕
したものでも良い。The present inventor synthesized mullite prize spherical powders with various compositions by homogeneously mixing high-purity alumina sol and silica sol, and then firing the mixture at a temperature of 500°C to 1600°C while spraying. When using quality spherical powder alone as raw material powder, alumina powder,
When silica powder and mullite award-winning non-spherical powder are added as raw material powder, the strength of the obtained mullite sintered body is sufficiently high, there is little variation, and the strength decreases little at high temperatures. We worked hard to find a way to easily produce the aggregates. As a result, when a mixture of alumina sol and silica sol is sprayed, it becomes a spherical powder, but if the firing temperature during spraying is low, it becomes an amorphous aggregate with a large specific surface area, resulting in poor formability.
It has been found that when a mullite sintered body is produced using such a material as a starting material, it is difficult to obtain a mullite sintered body as the object of the present invention. In other words, when the above-mentioned powder is used as a starting material, the compacting density is low, the firing shrinkage is large, and it is unstable, resulting in cracks during firing and large variations in shape and dimensions after sintering. It is. Furthermore, as the firing temperature during spraying of the mixture of alumina sol and silica sol is increased, the specific surface area of the spherical powder becomes extremely small, and mullite crystals are formed from amorphous. Furthermore, it has been found that as the firing temperature during spraying is increased, the crystallite size of mullite crystals changes from fine to large. Based on these findings, further research has been carried out, and as a result, the object of the present invention is to provide a mullite powder, which has a mullite crystallite diameter of 200.
nm or less, and the weight ratio of Al2O, /SiO□ is 4
It has been found that this can be achieved by using a raw material powder of a mullite-based sintered body characterized by having a spherical particle size of 0/60 to 80/20 and an average particle size of 10 μm or less. Further, the mullite crystallite diameter is 200 nm or less, and A1
Spherical mullite powder with a weight ratio of □O, /Si○2 of 40/60 to 80/20 and an average particle size of 10 μm or less,
The mullite crystallite diameter is 200 nm or less, and Al
The weight ratio of tox/S i 02 is 40/60 to 80
/20 and a non-spherical mullite powder with an average particle size of 10 μm or less, and the non-spherical mullite powder is 80 parts by weight or less per 100 parts by weight of the spherical mullite powder. It has been found that this can be achieved by using a raw material powder of mullite sintered body. In addition, impurities other than Al2O3 and SiO2 are 0.5% by weight or less, and the weight ratio of A 1203 /S i Oz is 4.
The raw material composition is a mullite spherical powder having an average particle size of 10 μm or less and containing a mullite crystal phase with a crystallite size of 200 nm or less and having a value within the range of 0/60 to 80/20,
It has been found that this can be achieved by a method for producing a mullite sintered body, which is characterized by molding and firing a raw material containing this mullite spherical powder. In addition, 100 parts by weight of mullite spherical powder with an average particle size of 10 μm or less containing a mullite crystal phase with a crystallite size of 200 nm or less and containing impurities other than A I 20ff and SiO□ of 0.5% by weight or less; Mullite non-spherical powder with a particle size of 5 μm or less, A I 2 with an average particle size of 5 μm or less
A total of 80 powders of at least one kind selected from the group of 03 powder and 5iOz powder with an average particle size of 5 μm or less
Al2 in these raw material compositions, including parts by weight or less
The raw material composition is adjusted so that the weight ratio of O3/Si○2 is within the range of 40/60 to 80/20, and the raw material containing this mullite spherical powder is molded and fired. It has been found that this can be achieved by a method for producing a mullite sintered body. In the above method for producing a mullite-based sintered body, components other than alumina and silica, that is, impurities, in the mullite spherical powder serving as the starting material are allowed up to 0.5% by weight. still,
In applications where high temperature strength is important, the content of impurities is preferably 0.3% by weight or less, more preferably 0.1% by weight or less. In other words, when there are many impurities, the strength decreases significantly at high temperatures.In particular, when the amount exceeds 0.5% by weight, the strength decreases significantly at high temperatures.
It is easy to form pores that exceed 100%, and the strength variation becomes large. The weight ratio of starting materials alumina to silica is 40:60 to 8.
Although the ratio is within the range of 0:20, if strength at high temperatures is important, it is preferable to reduce the ratio of silica, that is, 65:35 to 80:20, more preferably 70:30 to 80. Preferably, the ratio is 20 to 20. The size of mullite crystallites in the mullite spherical powder as the starting material must be 200 nm or less, preferably 1100 nm or less, and it is necessary that it contains a crystalline phase of mullite crystallites, but it is necessary that it contains a glass phase or other crystalline phase. It may be included. That is, when the size of the mullite crystallites in the mullite spherical powder particles exceeds 200 nm, it becomes difficult to sinter,
It becomes difficult to manufacture a sintered body with sufficient strength. In addition, the average particle size of the mullite spherical powder as the starting material is 10μ.
If the size exceeds m, it will be difficult to sinter,
Because it is difficult to produce a sintered body with sufficient strength,
It is important that the average particle size is 10 μm or less, and 51
m or less is preferable. In particular, those having a diameter of 0.3 to 5 μm are preferable. 0 components other than Al2O3 and SiO2 as starting materials
．． In addition to mullite spherical powder with an average particle size of 10 μm or less containing a mullite crystal phase with a crystallite size of 200 nm or less at 5% by weight or less, mullite non-spherical powder, Al2O3
When at least one kind of powder selected from the group of powder and 5iC)z powder is used, the weight composition ratio of A1201 to SiO2 in these raw material compositions is 40
It must be adjusted to a value within the range of 60:20 to 80:20. The weight ratio of alumina to silica is 65:35 to 80:2.
0, more preferably 70:30 to 80:20. The mullite non-spherical powder, He1□03 powder and SlO□ powder preferably have an average particle size of 5 μm or less, more preferably 0.3 to 3 μm. In other words, if the average particle size becomes too large, it becomes difficult to sinter, while if the average particle size becomes too small, the formability becomes poor (and the stability of the shape and dimensions of the sintered body deteriorates. 5 μm or less, preferably 0.3 to 3 μm. Also, the addition ratio of alumina powder, silica powder, and mullite non-spherical powder is 8 parts by weight per 100 parts by weight of 1 spherical powder.
If the amount exceeds 0 parts by weight, the formability and sinterability will deteriorate, making it difficult to produce a good mullite sintered body. Mullite non-spherical powder of 5 am or less, Al 20s powder with an average particle size of 5 μm or less, and average particle size of 5 μm
It is preferable that the total amount of at least one kind of powder selected from the group of Sin and powders of m or less is 80 parts by weight or less. The mullite award powder as described above can be obtained by mixing hemite sol and silica sol in a predetermined ratio, gelling, and calcining. Hemite sol is obtained by peptizing an aqueous dispersion of γ-A Iz Oz (A100H) by adding an inorganic acid such as nitric acid or hydrochloric acid or an organic acid such as acetic acid or formic acid while heating it. There is. Examples of silica sol include colloidal aqueous solutions in which fine silica particles, such as white carbon produced by a wet method or fumed silica produced by a dry method, are dispersed in water. The alumina powder, silica powder, and mullite non-spherical powder used as starting materials are preferably of high purity, and the amount of impurities (final) in the mixture used as starting materials is 0.
It is 5% or less, preferably 0.3% or less. Further, the mullite non-spherical powder may be a pulverized product of mullite synthesized by an electrofusion method, or a pulverized mullite spherical powder.
表−１に示す粉末を出発原料として、ボールミルにて解
膠後、成形用バインダとしてポリビニルアルコール０．
８重量部とポリエチレングリコール２重量部を加えて２
０時間混合後、スプレードライ法により乾燥造粒し、プ
レス成形により成形後、１６００℃〜１６８０°Ｃにて
３時間焼成してムライト質焼結体を作製した。
得られたムライト質焼結体について室温と１２００℃に
て抗折強度を測定した。又、破断サンプルを用いて走査
型電子顕微鏡（ＳＥＭ）により内部気孔の観察を行った
。
尚、用いたアルミナ粉末とシリカ粉末の純度は９９．９
％であり、ムライト質非球状粉末はアルミナ対シリカの
重量比が７０対３０で、不純物は０．１以下であった。Using the powder shown in Table 1 as a starting material, after peptizing it in a ball mill, 0% polyvinyl alcohol was used as a molding binder.
Add 8 parts by weight and 2 parts by weight of polyethylene glycol to make 2
After mixing for 0 hours, the mixture was dried and granulated by spray drying, molded by press molding, and then fired at 1600°C to 1680°C for 3 hours to produce a mullite sintered body. The bending strength of the obtained mullite sintered body was measured at room temperature and 1200°C. Furthermore, internal pores were observed using a scanning electron microscope (SEM) using the fractured sample. The purity of the alumina powder and silica powder used was 99.9.
%, and the mullite non-spherical powder had a weight ratio of alumina to silica of 70:30, and impurities were 0.1 or less.
Claims (6)
ライト結晶子径が２００ｎｍ以下であって、Ａ１＿２Ｏ
＿３／ＳｉＯ＿２の重量比が４０／６０〜８０／２０で
、平均粒径が１０μｍ以下の球状のものであることを特
徴とするムライト質焼結体の原料粉末。(1) Mullite powder, the mullite crystallite diameter of this mullite powder is 200 nm or less, and A1_2O
A raw material powder for a mullite-based sintered body, characterized in that it has a spherical shape with a weight ratio of _3/SiO_2 of 40/60 to 80/20 and an average particle size of 10 μm or less.
ｌ＿２Ｏ＿３／ＳｉＯ＿２の重量比が４０／６０〜８０
／２０で、平均粒径が１０μｍ以下の球状のムライト質
粉末と、ムライト結晶子径が２００ｎｍ以下であって、
Ａｌ＿２Ｏ＿３／ＳｉＯ＿２の重量比が４０／６０〜８
０／２０で、平均粒径が１０μｍ以下の非球状のムライ
ト質粉末とを含み、前記球状のムライト質粉末１００重
量部に対して前記非球状のムライト質粉末が８０重量部
以下であることを特徴とするムライト質焼結体の原料粉
末。(2) Mullite crystallite diameter is 200 nm or less, and A
The weight ratio of l_2O_3/SiO_2 is 40/60 to 80
/20, a spherical mullite powder with an average particle size of 10 μm or less, and a mullite crystallite size of 200 nm or less,
Weight ratio of Al_2O_3/SiO_2 is 40/60 to 8
0/20 and a non-spherical mullite powder with an average particle size of 10 μm or less, and the amount of the non-spherical mullite powder is 80 parts by weight or less per 100 parts by weight of the spherical mullite powder. Raw material powder for characteristic mullite sintered bodies.
さらに含まれてなる特許請求の範囲第１項又は第２項記
載のムライト質焼結体の原料粉末。(3) The raw material powder for a mullite sintered body according to claim 1 or 2, further comprising Al_2O_3 powder and/or SiO_2 powder.
．５重量％以下である特許請求の範囲第１項〜第３項記
載のムライト質焼結体の原料粉末。(4) Impurities other than Al_2O_3 and SiO_2 are 0
．． A raw material powder for a mullite sintered body according to claims 1 to 3, wherein the content is 5% by weight or less.
．５重量％以下で、Ａｌ＿２Ｏ＿３／ＳｉＯ＿２の重量
比が４０／６０〜８０／２０の範囲内の値であって、結
晶子の大きさが２００ｎｍ以下のムライト結晶相を含む
平均粒径１０μｍ以下のムライト質球状粉末を原料組成
とし、このムライト質球状粉末を含む原料を成形、焼成
することを特徴とするムライト質焼結体の製造方法。(5) Impurities other than Al_2O_3 and SiO_2 are 0
．． Mullite with an average grain size of 10 μm or less containing a mullite crystal phase with a weight ratio of Al_2O_3/SiO_2 of 40/60 to 80/20 at 5% by weight or less and a crystallite size of 200 nm or less 1. A method for producing a mullite sintered body, characterized in that the raw material composition is a mullite spherical powder, and the raw material containing the mullite spherical powder is molded and fired.
．５重量％以下で、結晶子の大きさが２００ｎｍ以下の
ムライト結晶相を含む平均粒径１０μｍ以下のムライト
質球状粉末１００重量部と、平均粒径が５μｍ以下のム
ライト質非球状粉末、平均粒径が５μｍ以下のＡｌ＿２
Ｏ＿３粉末及び平均粒径が５μｍ以下のＳｉＯ＿２粉末
の群の中から選ばれる少なくとも一種以上の粉末が合計
８０重量部以下とを含み、これらの原料組成におけるＡ
ｌ＿２Ｏ＿３／ＳｉＯ＿２の重量比が４０／６０〜８０
／２０の範囲内の値となるよう調整されてなるものを原
料組成とし、このムライト質球状粉末を含む原料を成形
、焼成することを特徴とするムライト質焼結体の製造方
法。(6) Impurities other than Al_2O_3 and SiO_2 are 0
．． 100 parts by weight of a mullite spherical powder with an average particle size of 10 μm or less containing a mullite crystal phase with a crystallite size of 200 nm or less and 5% by weight or less, and a mullite non-spherical powder with an average particle size of 5 μm or less, average grain Al_2 with a diameter of 5 μm or less
A total of 80 parts by weight or less of at least one kind of powder selected from the group of O_3 powder and SiO_2 powder with an average particle size of 5 μm or less, and A in these raw material compositions.
The weight ratio of l_2O_3/SiO_2 is 40/60 to 80
A method for producing a mullite sintered body, characterized in that the raw material composition is adjusted to have a value within the range of /20, and the raw material containing this mullite spherical powder is molded and fired.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2-216725 | 1990-08-17 | ||
| JP21672590 | 1990-08-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04175264A true JPH04175264A (en) | 1992-06-23 |
Family
ID=16692948
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2325926A Pending JPH04175264A (en) | 1990-08-17 | 1990-11-29 | Raw material powder of mullite based sintered compact and production of mullite based sintered compact |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04175264A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8735309B2 (en) | 2010-09-28 | 2014-05-27 | Kyocera Corporation | Mullite-based sintered body, circuit board using same and probe card |
| WO2015186560A1 (en) * | 2014-06-06 | 2015-12-10 | 日本碍子株式会社 | Mullite sintered compact, method for producing same, and composite substrate |
-
1990
- 1990-11-29 JP JP2325926A patent/JPH04175264A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8735309B2 (en) | 2010-09-28 | 2014-05-27 | Kyocera Corporation | Mullite-based sintered body, circuit board using same and probe card |
| WO2015186560A1 (en) * | 2014-06-06 | 2015-12-10 | 日本碍子株式会社 | Mullite sintered compact, method for producing same, and composite substrate |
| JP5861016B1 (en) * | 2014-06-06 | 2016-02-16 | 日本碍子株式会社 | Sintered mullite, its manufacturing method and composite substrate |
| US9776924B2 (en) | 2014-06-06 | 2017-10-03 | Ngk Insulators, Ltd. | Mullite sintered body, method for producing the same, and composite substrate |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Lee et al. | Crystallization and densification of nano‐size amorphous cordierite powder prepared by a PVA solution‐polymerization route | |
| JP2010508231A (en) | Compound for manufacturing heat-resistant materials | |
| JPS6117469A (en) | Manufacture of minute cordierite | |
| JPS6054976A (en) | Silicon nitride sintered body and manufacture | |
| JPH0388762A (en) | Production of mullite-cordierite combined ceramics | |
| JPH02111658A (en) | Ceramic insulating material and production thereof | |
| JPH04175264A (en) | Raw material powder of mullite based sintered compact and production of mullite based sintered compact | |
| JP2527744B2 (en) | Structure included in electronic circuit packaging and manufacturing method | |
| JP3217502B2 (en) | Cordierite powder and method for producing porcelain | |
| KR101200718B1 (en) | Fabrication method of high density & high fracture toughness silica radome | |
| KR100381097B1 (en) | Method for preparing of silica sleeve for hearth roll | |
| JPS63103864A (en) | Sintered formed body comprising partially stabilized zirconium oxide and manufacture | |
| JPH06100358A (en) | Production of mullite sintered compact | |
| JP3888714B2 (en) | Alumina sintered body | |
| JPS6360106A (en) | Spinel powder and its production | |
| JPS6357383B2 (en) | ||
| JPH04209761A (en) | Zirconia porcelain and its production | |
| JPH08175864A (en) | Production of low-temperature sintered anorthite-gehlenite ceramic | |
| JP2000159570A (en) | Production of compact cordierite sintered product | |
| JPH06219828A (en) | Production of mullite-silicon carbide combined ceramics | |
| JPH02296717A (en) | Aluminum oxide powder of improved treatment characteristics, its production and its use | |
| JPS62275067A (en) | Manufacture of silicon nitride sintered body | |
| JP3042899B2 (en) | Mixture of fine-grained barium titanate and method for producing the same | |
| KR100419060B1 (en) | A method of preparing silica sleeve for hearth roll by sol-gel process | |
| KR100419061B1 (en) | A method of preparing silica sleeve for hearth roll by slip casting |