JP3121996B2 - Alumina sintered body - Google Patents
Alumina sintered bodyInfo
- Publication number
- JP3121996B2 JP3121996B2 JP06293029A JP29302994A JP3121996B2 JP 3121996 B2 JP3121996 B2 JP 3121996B2 JP 06293029 A JP06293029 A JP 06293029A JP 29302994 A JP29302994 A JP 29302994A JP 3121996 B2 JP3121996 B2 JP 3121996B2
- Authority
- JP
- Japan
- Prior art keywords
- alumina
- phase
- sintered body
- dispersed phase
- volume
- 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 - Fee Related
Links
Description
【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION
【０００１】[0001]
【産業上の利用分野】本発明は、強度，靭性に優れたア
ルミナ質焼結体に関わり、例えば、航空・宇宙業界，製
錬業界，化学業界で用いられたり、ガスタ−ビンエンジ
ン，自動車部品，切削工具材料等に好適に使用されるア
ルミナ質焼結体に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alumina sintered body having excellent strength and toughness, for example, used in the aviation and space industry, smelting industry, chemical industry, gas turbine engine, and automobile parts. The present invention relates to an alumina-based sintered body that is suitably used as a material for cutting tools.
【０００２】[0002]
【従来の技術】従来から、耐高温の構造部材として、ア
ルミナは耐環境性，高温強度ともに優れることで注目さ
れていたが、アルミナ固有の欠点である高温軟化と低靭
性により、その用途が限られていた。2. Description of the Related Art Conventionally, alumina has been attracting attention as a high-temperature-resistant structural member because of its excellent environmental resistance and high-temperature strength. However, its use is limited due to the high-temperature softening and low toughness inherent to alumina. Had been.
【０００３】そこで、近年では、アルミナの高温強度と
破壊靭性を向上させるために、種々の複合化が試みられ
ている。例えば、Ａｌ2 Ｏ3 −ＳｉＣナノコンポジィッ
ト、Ａｌ2 Ｏ3 −ＺｒＯ2 複合材料、および異方性β−
Ａｌ2 Ｏ3 を分散させたアルミナ質焼結体が知られてお
り（例えば、特開昭６１−１２２１６４号公報、特開昭
６３−１２９０４４号公報，特開昭６３−１３４５５１
号公報等参照）、このように複合化することにより、純
粋なアルミナの焼結体より強度と靭性を向上することが
できる。[0003] In recent years, various attempts have been made to combine alumina in order to improve the high-temperature strength and fracture toughness of alumina. For example, Al 2 O 3 —SiC nanocomposite, Al 2 O 3 —ZrO 2 composite, and anisotropic β-
Alumina sintered bodies in which Al 2 O 3 is dispersed are known (for example, JP-A-61-122164, JP-A-63-129944, and JP-A-63-134551).
In this case, the strength and toughness can be improved as compared with a pure alumina sintered body.
【０００４】[0004]
【発明が解決しようとする問題点】しかしながら、上記
Ａｌ2 Ｏ3 −ＳｉＣナノコンポジィットでは非酸化物の
ＳｉＣを分散させているために、酸化雰囲気において高
温状態で使用される場合には高温での耐酸化性に欠ける
という問題があった。However, since the non-oxide SiC is dispersed in the Al 2 O 3 —SiC nanocomposite, when the Al 2 O 3 —SiC nanocomposite is used in a high temperature state in an oxidizing atmosphere, the temperature is high. However, there is a problem that the oxidation resistance is insufficient.
【０００５】また、Ａｌ2 Ｏ3 −ＺｒＯ2 複合材料は９
００℃付近の温度で強度が急激に低下するため、高温強
度が低く、高温下において応力が作用するような状態で
の使用には適しないという問題があった。The Al 2 O 3 —ZrO 2 composite material is 9
Since the strength sharply decreases at a temperature around 00 ° C., there is a problem that the high-temperature strength is low, and it is not suitable for use in a state where a stress acts at a high temperature.
【０００６】さらに、異方性β−Ａｌ2 Ｏ3 分散アルミ
ナ焼結体では、通常の焼成温度では、アルミナ母相の結
晶粒子の成長速度がβ−Ａｌ2 Ｏ3 の結晶粒子の成長速
度より大きいため、異方性結晶による強化効果がアルミ
ナ結晶の粒成長により大きく低減するという問題があっ
た。このようなアルミナ結晶の粒成長を抑制するため
に、高純度原料を使用することが考えられるが、原料コ
ストと焼結コストが大幅に増加するために、実際製品化
することは難しいという問題があった。Further, in the anisotropic β-Al 2 O 3 dispersed alumina sintered body, at a normal firing temperature, the growth rate of the crystal grains of the alumina matrix is lower than that of the β-Al 2 O 3 crystal grains. Since it is large, there is a problem that the strengthening effect by the anisotropic crystal is greatly reduced by the grain growth of the alumina crystal. In order to suppress such alumina crystal grain growth, it is conceivable to use a high-purity raw material. However, since the raw material cost and the sintering cost are greatly increased, there is a problem that it is difficult to commercialize the raw material. there were.
【０００７】本発明は、高温での強度と耐酸化性に優
れ、さらに、アルミナ結晶の粒成長を抑制することによ
り破壊靭性を向上したアルミナ質焼結体を提供すること
を目的とするものである。SUMMARY OF THE INVENTION It is an object of the present invention to provide an alumina-based sintered body which is excellent in strength and oxidation resistance at high temperatures and has improved fracture toughness by suppressing the growth of alumina crystal grains. is there.
【０００８】[0008]
【問題点を解決するための手段】本発明者は、アルミナ
質焼結体の室温強度，高温強度および破壊靭性を向上す
るためには、従来技術のように異方性を有する結晶粒子
を分散して複合化するだけでなく、アルミナ結晶の粒成
長をも同時に制御することが重要であるという見地に基
づいて研究を重ねた結果、焼成温度で安定な等方性分散
相をさらに複合化させると、アルミナ結晶の粒成長を抑
制する効果が大きく、等方性分散相量の増加によりアル
ミナ結晶の粒径と粒径分布が変化し、異方性分散相と組
み合せることにより室温強度，高温強度および破壊靭性
が優れたアルミナ質焼結体を低コストで得られることを
見出し、本発明に至った。In order to improve the room temperature strength, high temperature strength and fracture toughness of an alumina-based sintered body, the present inventors disperse anisotropic crystal grains as in the prior art. As a result of repeated studies based on the viewpoint that it is important to control not only the growth of alumina crystals but also the growth of alumina crystals at the same time, it is possible to further compose an isotropic dispersed phase that is stable at the firing temperature. In addition, the effect of suppressing the grain growth of alumina crystals is great, and the increase in the amount of isotropic dispersed phase changes the grain size and particle size distribution of alumina crystals. The present inventors have found that an alumina-based sintered body having excellent strength and fracture toughness can be obtained at low cost, and have reached the present invention.
【０００９】即ち、本発明のアルミナ質焼結体は、少な
くともアルミナ母相と、β−Ａ１ 2 ０ 3 からなる異方性分
散相と、ガーネット相および／またはペロブスカイト相
からなる等方性分散相を含有するとともに、粒径５〜２
０μｍのアルミナ結晶粒子が前記アルミナ母相全体の１
０〜６０体積％であり、粒径５μｍ未満のアルミナ結晶
粒子が前記アルミナ母相全体の４０〜９０体積％である
ものである。また、上記の異方性分散柏がＬａ，Ｃａ，
Ｓｒ，Ｂａのうち少なくとも１種を含有したβ−Ａ１2
０3であり、上記の等方性分散相がＹ，Ｄｙ，Ｅｒ、Ｙ
ｂ，Ｌｕのうち少なくとも１種を含有したガーネット相
および／またはペロブスカイト相であることが望まし
い。[0009] That is, the alumina sintered body of the present invention includes at least alumina matrix, the anisotropic dispersed phase consisting of β-A1 2 0 3, garnet phase and / or perovskite phase
With containing isotropic dispersed phase consisting of, particle size 5-2
0 μm alumina crystal particles constitute 1% of the entire alumina matrix.
Alumina crystal particles having a particle size of 0 to 60% by volume and a particle size of less than 5 μm constitute 40 to 90% by volume of the whole alumina matrix. In addition, the above anisotropic dispersion is La, Ca,
Sr, and containing at least one of Ba beta-A1 2
0 3 and the above isotropic dispersed phase is Y, Dy, Er, Y
A garnet phase and / or a perovskite phase containing at least one of b and Lu are desirable.
【００１０】本発明においては、β−Ａ１ 2 ０ 3 からなる
異方性分散相が存在するものであるが、この異方性分散
相は、焼結体におけるクラックの進展を防止し、高温に
おける粒界滑りを防止するため、室温と高温における強
度を向上するものである．[0010] In the present invention are those which <br/> anisotropic dispersed phase consisting of β-A1 2 0 3 is present, the anisotropic dispersed phase, preventing the development of cracks in the sintered body In order to prevent grain boundary sliding at high temperature, the strength at room temperature and high temperature is improved.
【００１１】β−Ａ１ 2 ０ 3 からなる異方性分散相の粒径
が小さい場合には、上記のような室温強度や高温強度向
上の効果が小さく、逆に大きすぎると破壊源と成る可能
性がある。よって本発明に用いられるβ−Ａ１ 2 ０ 3 から
なる異方性分散相は、長後方向の長さが５〜３０μｍ、
特に８〜２０μｍとすることが望ましい。また、上記の
異方性分散相のアスペクト比は大きい方が強化効果が顆
著であることから、少なくとも２以上、好ましくは４以
上が良い。さらに、上記の異方性分散相の含有量が少な
い場合には上記効果が小さいため、上記の異方性分散相
は全量中５体積％以上含有することが望ましく、また、
アルミナの特性を失わない程度の５０体積％まで分散さ
せるとができる。[0011] When the particle size of the β-A1 2 0 3 consists of anisotropic dispersed phase is small, room temperature strength and the effect of improving the high temperature strength as described above is small, and be made with fracture sources too large conversely There is. Thus the β-A1 2 0 3 used in the present invention
The anisotropic dispersed phase has a length in the long-rear direction of 5 to 30 μm,
In particular, it is desirable to set it to 8 to 20 μm. The aspect ratio is greater strengthening effect of the above <br/> anisotropic dispersed phase since it is顆著, at least 2 or more, preferably 4 or more is good. Further, when the content of the anisotropic dispersed phase is small, the effect is small. Therefore, the anisotropic dispersed phase is desirably contained at 5% by volume or more based on the total amount.
It can be dispersed up to 50% by volume so as not to lose the properties of alumina.
【００１２】本発明では、β−Ａ１ 2 ０ 3 からなる異方性
分散相とともにガーネット相および／またはペロブスカ
イト相からなる等方性分散相を含有することが重要であ
る。従来、焼成温度におけるアルミナ結晶の粒成長が速
いことは知られている。アルミナ結晶粒径が上記の異方
性分散相の長径方向のサイズと同等になれば、前述した
異方位分散相の強化効果がなくなると考えられる。アル
ミナ結晶の粒成長を抑制するためには、高温で安定な微
細粒子を分散することが効果的である。このため、本発
明ではガーネット相および／またはペロブスカイト相か
らなる等方性分散相を含有させたのである。このような
等方性分散相を複合化させることにより、焼結性が向上
し、常庄下において比較的低温での焼成でも緻密な焼結
体が得られる。In the present invention, the garnet phase together with β-A1 2 0 3 consists of anisotropic dispersed phase and / or Perobusuka
It is important to contain an isotropic dispersed phase consisting of a silica phase . Conventionally, it is known that the grain growth of alumina crystals at the firing temperature is fast. If the alumina crystal grain size becomes equal to the size in the major axis direction of the anisotropic dispersed phase, it is considered that the strengthening effect of the differently oriented dispersed phase described above is lost. In order to suppress the alumina crystal grain growth, it is effective to disperse fine particles stable at high temperatures. Therefore, in the present invention, the garnet phase and / or the perovskite phase
It contained an isotropic dispersed phase. By compounding such an isotropic dispersed phase, the sinterability is improved, and a dense sintered body can be obtained even when firing at a relatively low temperature under ordinary conditions.
【００１３】ここで、ガーネット相および／またはペロ
ブスカイト相からなる等方性分散相の平均結晶粒径は５
μｍ以下、特に３μｍ以下であることが望ましい。上記
の等方性分散相の平均結晶粒径が５μｍ以上となると、
アルミナ結晶の粒成長を抑制する効果が低下するからで
ある。また、上記の等方性分散相の含有量は全量中１〜
３０体積％であることが望ましい。これは、上記の等方
性分散相が全量中１体積％よりも少ないとアルミナ母相
の粒成長抑制効果が小さく、３０体積％よりも大きくな
ると組織が過度に微細化され、逆に材料の高温特性を低
下させるからである。上記の等方性分散相の含有量は、
特に全量中１〜２０体積％であることが望ましい。Here, the garnet phase and / or perro
The average crystal grain size of the isotropic dispersed phase composed of the bouskite phase is 5
It is desirable that it is not more than 3 μm, especially not more than 3 μm. the above
When the average crystal grain size of the isotropic dispersed phase is 5 μm or more,
This is because the effect of suppressing the alumina crystal grain growth is reduced. The content of the above isotropic dispersed phase 1 in a total volume of
Desirably, it is 30% by volume. This is above the isotropic dispersed phase less than 1 vol% in a total volume of smaller grain growth inhibiting effect of the alumina matrix phase, 30% by volume greater than the tissue is excessively fine, conversely materials This is because high-temperature characteristics are deteriorated. The content of the above isotropic dispersed phase,
In particular, the content is preferably 1 to 20% by volume of the total amount.
【００１４】さらに、アルミナ母相については、粒径が
微細であれば高温特性および破壊靭性が低下する。粒径
が大きければ異方性による高強度化，高靭性化効果を減
少し、強度を劣化させる。本発明で特に重要なのは、ア
ルミナ結晶の内、５μｍ未満の微細粒と５〜２０μｍの
粗大粒が同時に存在すると、上記の欠点がなくなり、強
度，靭性，高温強度がともに高いアルミナ質焼結体が得
られるところにある。Further, with respect to the alumina matrix phase, if the particle size is fine, the high-temperature properties and the fracture toughness deteriorate. If the grain size is large, the effect of increasing strength and toughness due to anisotropy is reduced, and strength is deteriorated. What is particularly important in the present invention is that when the fine grains of less than 5 μm and the coarse grains of 5 to 20 μm are present at the same time in the alumina crystal, the above-mentioned disadvantages are eliminated, and an alumina sintered body having high strength, toughness and high-temperature strength is obtained. Where you can get it.
【００１５】これら細粒と粗粒の二種類の結晶粒径およ
び存在量は、β−Ａ１ 2 ０ 3 の粒径と形状、およびガーネ
ット相および／またはペロブスカイト相との粒径と量の
組合せにより任意に調整できるが、粒径５〜２０μｍの
粗粒はアルミナ母相全体の１０〜６０体積％、特には１
５〜４０体積％が望ましく、粒径５μｍ未満の細粒はア
ルミナ母相全体の４０〜９０体積％、特には６０〜８５
体積％が望ましい。[0015] Two types of crystal grain size and abundance of these fine and coarse grains, β-A1 2 0 3 of particle size and shape, and Gane
It can be arbitrarily adjusted by a combination of the particle size and the amount with the wet phase and / or the perovskite phase.
5 to 40% by volume is desirable, and fine particles having a particle size of less than 5 μm are 40 to 90% by volume, particularly 60 to 85% by volume of the whole alumina matrix.
% By volume is desirable.
【００１６】異方性分散相としては複合酸化物のβ−Ａ
１2０3、等方性分散相には高温安定性およびヤング率が
高いことから、複合酸化物のペロブスカイト相、ガーネ
ット相を用いることが重要である。上記β−Ａ１2０3の
中でも、特にＬａ，Ｃａ，Ｓｒ，Ｂａなどを含むもの
は、安定性が高く、異方性が発達しやすいから好まし
い。また、ガーネット相および／またはペロブスカイト
相では、特にＹ，Ｄｙ，Ｅｒ，Ｙｂ，Ｌｕを含むものは
安定性と高温強度特性に優れているため好ましい。As the anisotropic dispersed phase, the complex oxide β-A
1 2 0 3, the isotropic dispersed phase due to its high temperature stability and the Young's modulus, it is important to use perovskite phase of the composite oxide, the garnet phase. Among the β-A1 2 0 3, in particular La, Ca, Sr, those including Ba has high stability, anisotropy is preferred from easy development. Garnet phase and / or perovskite
Among the phases , those containing Y, Dy, Er, Yb, and Lu are particularly preferred because they have excellent stability and high-temperature strength characteristics.
【００１７】ペロブスカイト相としては、例えば、Ａｌ
ＭＯ3 として表されるもの、ガーネット相としては、例
えば、Ａｌ3 Ｍ5 Ｏ12として表されるものがある。ここ
で、Ｍとしては、上記したＹ，Ｄｙ，Ｅｒ，Ｙｂ，Ｌｕ
以外にＮｄ，Ｓｍ，Ｅｕ等でも良い。As the perovskite phase, for example, Al
As the garnet phase represented by MO 3 , for example, there is a garnet phase represented by Al 3 M 5 O 12 . Here, M is Y, Dy, Er, Yb, Lu described above.
Besides, Nd, Sm, Eu, etc. may be used.
【００１８】本発明のアルミナ質焼結体は、アルミナ粉
末に、公知の原料、例えば、Ｌａ，Ｃａ，Ｓｒ，Ｂａ，
Ｙ，Ｄｙ，Ｅｒ，Ｙｂ，Ｌｕ等の金属粉末、あるいはこ
れらの金属の酸化物粉末、あるいは前記金属を含む有
機，無機物およびそれらの溶液を用いて所定の組成に調
合、混合し、その後公知の成型手段により成形し、この
成形体を公知の焼結法により焼成する。The alumina-based sintered body of the present invention is prepared by adding known raw materials such as La, Ca, Sr, Ba,
Using a metal powder such as Y, Dy, Er, Yb, Lu, or the like, or an oxide powder of these metals, or an organic or inorganic substance containing the metal, or a solution thereof, mixing and mixing to a predetermined composition, and thereafter, a known method. It is molded by molding means, and the molded body is fired by a known sintering method.
【００１９】公知の成型手段としては、例えば、金型プ
レス，鋳込み成型，押出成型，射出成型，冷間静水圧プ
レスなどがあり、公知の焼結法としては、例えば、ホッ
トプレス法，常圧焼成法，ガス加圧焼成法があり、更
に、これらの焼成後に熱間静水圧処理（ＨＩＰ）処理、
およびガラスシール後ＨＩＰ処理してもよい。このよう
にして本発明では対理論密度比９５％以上の緻密な焼結
体を得る。焼成温度が低ければ、緻密化しにくく、逆に
高すぎると粗大な粒子が生成するため、焼成温度は、１
５００℃〜１７５０℃の温度範囲が好適である。Known molding means include, for example, mold pressing, casting, extrusion molding, injection molding, and cold isostatic pressing. Known sintering methods include, for example, hot pressing and normal pressure. There are a sintering method and a gas pressure sintering method, and after these sintering, a hot isostatic pressure (HIP) treatment,
After the glass sealing, HIP processing may be performed. Thus, in the present invention, a dense sintered body having a theoretical density ratio of 95% or more is obtained. If the firing temperature is low, it is difficult to densify, and if it is too high, coarse particles are generated.
A temperature range from 500C to 1750C is preferred.
【００２０】尚、本発明のアルミナ質焼結体では、例え
ば、マグネシア，ジルコニア，ムライト等の酸化物を一
定量添加しても、特性には殆ど影響を与えないため、強
度と靱性を向上するために上記酸化物を複合化させるこ
ともできる。In the alumina sintered body of the present invention, even if an oxide such as magnesia, zirconia, or mullite is added in a certain amount, the properties are hardly affected, so that the strength and toughness are improved. For this purpose, the above oxides can be compounded.
【００２１】[0021]
【作用】本発明のアルミナ質焼結体は、アルミナ結晶の
粗界にβ−Ａ１ 2 ０ 3 とガーネット相および／またはペロ
ブスカイト相とを存在させ、粒径５〜２０μｍのアルミ
ナ結晶粒子をアルミナ母相全体の１０〜６０体積％と
し、粒径５μｍ未満のアルミナ結晶粒子をアルミナ母相
全体の４０〜９０体積％とすることにより、高温での耐
酸化性に優れるとともに、室温から高温まで優れた強度
と破壊靭性を有する高温構造材料を提供することができ
る．Alumina sintered body of the working of the present invention is the coarse boundary of alumina crystal β-A1 2 0 3 and the garnet phase and / or Pero
The presence of a Busukaito phase, the alumina crystal particles having a particle size 5~20μm and 10-60% by volume of the total alumina matrix, the alumina crystal grain size of less than 5μm and 40 to 90 volume% of the total alumina matrix As a result, it is possible to provide a high-temperature structural material having excellent resistance to oxidation at high temperatures and excellent strength and fracture toughness from room temperature to high temperatures.
【００２２】即ち、β−Ａ１ 2 ０ 3 を複合化させることに
より、焼結体におけるクラックの進展を抑制し、高温に
おける粒界滑りを防止し、また、ガーネット相および／
またはペロブスカイト相を複合化させることにより、ア
ルミナ結晶の粒成長を抑制し、焼結性が向上し、さら
に、アルミナ結晶粒子の粒径分布を制御することによ
り、高温特性および破壊靭性を向上することができるの
である。[0022] That is, by compounding a β-A1 2 0 3, to suppress the progress of cracks in the sintered body, to prevent grain boundary sliding at high temperatures, also, garnet phase and /
Alternatively, by compounding the perovskite phase , the grain growth of alumina crystals is suppressed, sinterability is improved, and further, by controlling the particle size distribution of alumina crystal particles, high temperature characteristics and fracture toughness are improved. You can do it.
【００２３】[0023]
【実施例】表１に示すような酸化物原料粉末を、表１に
示す組成比で調合し、１ｔ／ｃｍ2 の圧力で金型成形し
た後、３ｔ／ｃｍ2 の圧力で冷間静水圧処理を加えた。
そして、表１に示すような焼成条件で大気中で焼成し
た。EXAMPLE An oxide raw material powder as shown in Table 1 was prepared at a composition ratio shown in Table 1, and was molded at a pressure of 1 t / cm 2 and then subjected to cold isostatic pressure at a pressure of 3 t / cm 2. Processing was added.
Then, it was fired in the air under the firing conditions shown in Table 1.
【００２４】[0024]
【表１】 [Table 1]
【００２５】得られた焼結体をＪＩＳ−Ｒ１６０１にて
指定されている形状まで研磨し抗折試料を作製した。こ
の試料についてＪＩＳ−Ｒ１６０１に基づく室温および
１４００℃での４点曲げ抗折強度試験を実施した。ま
た、ビッカース圧痕法により破壊靭性（Ｋ1c）を測定し
た。焼結体の組織を、鏡面研磨試料を光学顕微鏡および
走査型電子顕微鏡で観察し、格子点数集計法により母相
の粗粒、細粒の体積分率を求めた。Ｘ線回折測定および
マイクロ組織分析により焼結体中のβ−Ａ１ 2 ０ 3 結晶
と、ガーネット相および／またはペロブスカイト相とを
同定した。これらの結果を表２に示した。表２におい
て、粗粒とは５〜２０μｍのアルミナ結晶粒子であり、
細粒とは５μｍ未満のアルミナ結晶粒子である。The obtained sintered body was polished to a shape specified by JIS-R1601, to prepare a bending specimen. This sample was subjected to a four-point bending strength test at room temperature and 1400 ° C. based on JIS-R1601. The fracture toughness (K 1c ) was measured by the Vickers indentation method. The structure of the sintered body was observed by using a mirror-polished sample with an optical microscope and a scanning electron microscope, and the volume fraction of coarse particles and fine particles of the matrix was determined by a grid point counting method. Β-A1 2 0 3 crystal sintered body by X-ray diffraction measurement and microstructure analysis
And a garnet phase and / or a perovskite phase . Table 2 shows the results. In Table 2, coarse particles are alumina crystal particles of 5 to 20 μm,
Fines are alumina crystal particles of less than 5 μm.
【００２６】[0026]
【表２】 [Table 2]
【００２７】表２の結果から、β−Ａ１ 2 ０ 3 と、ガーネ
ット相および／またはペロブスカイト相とが含まれ、ア
ルミナ結晶粒子の粒径分布を制御した本発明のアルミナ
質焼結体は、従来のアルミナ材料およびアルミナ基複合
材料に比べて、より優れた室温強度と高温強度および破
壊靭性を示すことが分かる。[0027] from the results in Table 2, and β-A1 2 0 3, Gane
The alumina-based sintered body according to the present invention, which includes the alumina phase and / or the perovskite phase and controls the particle size distribution of the alumina crystal particles, has a higher room temperature than the conventional alumina material and alumina-based composite material. It can be seen that the steel exhibits strength, high-temperature strength, and fracture toughness.
【００２８】[0028]
【発明の効果】本発明のアルミナ質焼結体では、アルミ
ナ母相に対してβ−Ａ１ 2 ０ 3 からなる異方性分散相と、
ガーネット相および／またはペロブスカイト相からなる
等方性分散相とを複合化させ、粒径５〜２０μｍのアル
ミナ結晶粒子をアルミナ母相全体の１０〜６０体積％と
し、粒径５μｍ未満のアルミナ結晶粒子をアルミナ母相
全体の４０〜９０体積％とすることにより、高温での耐
酸化性に優れるとともに、室温から高温まで優れた強度
と破壊靭性を有する高温構造材料を提供することができ
る。The alumina sintered body of the present invention, an anisotropic dispersed phase consisting of β-A1 2 0 3 based on the alumina matrix,
Complexing with an isotropic dispersed phase consisting of a garnet phase and / or a perovskite phase to make alumina crystal particles having a particle size of 5 to 20 μm to 10 to 60% by volume of the whole alumina matrix, and a particle size of less than 5 μm By providing the alumina crystal particles of 40 to 90% by volume of the entire alumina matrix, it is possible to provide a high-temperature structural material having excellent oxidation resistance at high temperatures and excellent strength and fracture toughness from room temperature to high temperatures. it can.
【図１】本発明の試料の組織図である。FIG. 1 is a structural diagram of a sample of the present invention.
１・・・アルミナ結晶粒子 ２・・・異方性分散相 ３・・・等方性分散相 DESCRIPTION OF SYMBOLS 1 ... Alumina crystal particle 2 ... Anisotropic dispersion phase 3 ... Isotropic dispersion phase
Claims (2)
からなる異方性分散相と、ガーネット相および／または
ペロブスカイト相からなる等方性分散相を含有するとと
もに、粒径５〜２０μｍのアルミナ結晶粒子が前記アル
ミナ母相全体の１０〜６０体積％であり、粒径５μｍ未
満のアルミナ結晶粒子が前記アルミナ母相全体の４０〜
９０体積％であることを特徴とするアルミナ質焼結体。1. A and at least alumina matrix phase, β-A1 2 0 3
An anisotropic dispersed phase consisting of garnet phase and / or
In addition to containing an isotropic dispersed phase composed of a perovskite phase , alumina crystal particles having a particle size of 5 to 20 μm account for 10 to 60% by volume of the entire alumina matrix phase, and alumina crystal particles having a particle size of less than 5 μm correspond to the alumina mother particles. 40 ~
Alumina sintered body characterized in that it is 90% by volume.
うち少なくとも１種を含有したβ−Ａ１2０3であり、等
方性分散相がＹ，Ｄｙ，Ｅｒ，Ｙｂ，Ｌｕのうち少なく
とも１種を含有したガーネット相および／またはペロブ
スカイト相であることを特徴とする請求項１記載のアル
ミナ質焼結体。Wherein anisotropic dispersed phase La, Ca, Sr, a beta-A1 2 0 3 containing at least one of Ba, isotropic dispersed phase Y, Dy, Er, Yb, Lu The alumina-based sintered body according to claim 1, wherein the sinter is a garnet phase and / or a perovskite phase containing at least one of the following.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06293029A JP3121996B2 (en) | 1994-11-28 | 1994-11-28 | Alumina sintered body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06293029A JP3121996B2 (en) | 1994-11-28 | 1994-11-28 | Alumina sintered body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08151254A JPH08151254A (en) | 1996-06-11 |
| JP3121996B2 true JP3121996B2 (en) | 2001-01-09 |
Family
ID=17789574
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP06293029A Expired - Fee Related JP3121996B2 (en) | 1994-11-28 | 1994-11-28 | Alumina sintered body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3121996B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5770630B2 (en) * | 2008-08-13 | 2015-08-26 | オルムコ コーポレイション | Aesthetic orthodontic bracket and manufacturing method thereof |
| JP5272658B2 (en) * | 2008-10-31 | 2013-08-28 | 東ソー株式会社 | High-toughness and translucent alumina sintered body, manufacturing method and use thereof |
| AU2009238317B2 (en) | 2008-11-14 | 2011-10-06 | Ormco Corporation | Surface treated polycrystalline ceramic orthodontic bracket and method of making same |
-
1994
- 1994-11-28 JP JP06293029A patent/JP3121996B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH08151254A (en) | 1996-06-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1510509B1 (en) | Alumina/zirconia ceramics and method of producing the same | |
| JPH01257165A (en) | High temperature stable low thermal expansion ceramic and production thereof | |
| JPH07277814A (en) | Alumina-based ceramic sintered compact | |
| KR101794410B1 (en) | Sintered silicon nitride having high thermal conductivity and Manufacturing method thereof | |
| JP4465173B2 (en) | Composite ceramics and manufacturing method thereof | |
| JP2507479B2 (en) | SiC-Al Lower 2 O Lower 3 Composite Sintered Body and Manufacturing Method Thereof | |
| JP3279885B2 (en) | Method for producing alumina-based sintered body | |
| JP2005075659A (en) | Ceramic sintered compact, method for producing the same, and biomaterial | |
| JP3121996B2 (en) | Alumina sintered body | |
| JP2000256066A (en) | Silicon nitride-base sintered compact, its production and wear resistant member using same | |
| JP2777679B2 (en) | Spinel ceramics and manufacturing method thereof | |
| JP3145597B2 (en) | Alumina sintered body and method for producing the same | |
| JP2690571B2 (en) | Zirconia cutting tool and its manufacturing method | |
| JPH1179848A (en) | Silicon carbide sintered compact | |
| JP3340025B2 (en) | Alumina sintered body and method for producing the same | |
| JP3488350B2 (en) | Alumina sintered body and method for producing the same | |
| JP3152853B2 (en) | Alumina sintered body and method for producing the same | |
| Takano et al. | Microstructure and mechanical properties of ZrO 2 (2Y)-toughened Al 2 O 3 ceramics fabricated by spark plasma sintering | |
| JP3078462B2 (en) | Alumina sintered body and method for producing the same | |
| JP2581128B2 (en) | Alumina-sialon composite sintered body | |
| Kim et al. | Processing and characterization of multiphase ceramic composites part I: Duplex composites formed in situ from solution | |
| JP3618036B2 (en) | Alumina sintered body manufacturing method | |
| JP4243514B2 (en) | Composite ceramics and manufacturing method thereof | |
| JP3359443B2 (en) | Alumina sintered body and method for producing the same | |
| JP2947718B2 (en) | Method for producing silicon nitride based sintered body |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20071020 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081020 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091020 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101020 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101020 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111020 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20121020 Year of fee payment: 12 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20131020 Year of fee payment: 13 |
|
| LAPS | Cancellation because of no payment of annual fees |