JPS63301481A - Carbon heater and ceramic sintering furnace using it - Google Patents
Carbon heater and ceramic sintering furnace using itInfo
- Publication number
- JPS63301481A JPS63301481A JP13496087A JP13496087A JPS63301481A JP S63301481 A JPS63301481 A JP S63301481A JP 13496087 A JP13496087 A JP 13496087A JP 13496087 A JP13496087 A JP 13496087A JP S63301481 A JPS63301481 A JP S63301481A
- Authority
- JP
- Japan
- Prior art keywords
- carbon
- weight
- graphite
- heater
- carbon heater
- 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.)
- Granted
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 96
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 59
- 238000005245 sintering Methods 0.000 title claims abstract description 26
- 239000000919 ceramic Substances 0.000 title claims abstract description 16
- 239000010439 graphite Substances 0.000 claims abstract description 37
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 37
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 22
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 15
- 229910052742 iron Inorganic materials 0.000 claims abstract description 11
- 239000010703 silicon Substances 0.000 claims abstract description 10
- 238000010304 firing Methods 0.000 claims description 29
- 239000000463 material Substances 0.000 claims description 17
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 11
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 9
- 238000010438 heat treatment Methods 0.000 claims description 6
- 229910052575 non-oxide ceramic Inorganic materials 0.000 claims description 6
- 239000011225 non-oxide ceramic Substances 0.000 claims description 6
- 239000000843 powder Substances 0.000 claims description 6
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 6
- 239000002994 raw material Substances 0.000 claims description 4
- 150000004767 nitrides Chemical class 0.000 abstract description 15
- 239000012535 impurity Substances 0.000 abstract description 9
- 239000002245 particle Substances 0.000 abstract description 8
- 239000003795 chemical substances by application Substances 0.000 abstract description 4
- 239000013078 crystal Substances 0.000 abstract description 4
- 230000000703 anti-shock Effects 0.000 abstract 1
- 238000005204 segregation Methods 0.000 abstract 1
- 239000000126 substance Substances 0.000 abstract 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 15
- 229910001873 dinitrogen Inorganic materials 0.000 description 13
- 229920000049 Carbon (fiber) Polymers 0.000 description 11
- 239000004917 carbon fiber Substances 0.000 description 11
- 239000007789 gas Substances 0.000 description 11
- 150000004706 metal oxides Chemical class 0.000 description 10
- 239000010410 layer Substances 0.000 description 9
- 229910044991 metal oxide Inorganic materials 0.000 description 9
- 230000000694 effects Effects 0.000 description 8
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 6
- 238000000465 moulding Methods 0.000 description 6
- 239000001301 oxygen Substances 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 6
- 239000002344 surface layer Substances 0.000 description 6
- 230000006866 deterioration Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- 230000035939 shock Effects 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- 229910005091 Si3N Inorganic materials 0.000 description 4
- 239000000428 dust Substances 0.000 description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 229910052750 molybdenum Inorganic materials 0.000 description 3
- 239000011733 molybdenum Substances 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 2
- 210000000988 bone and bone Anatomy 0.000 description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 description 2
- 238000009694 cold isostatic pressing Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 238000007667 floating Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000001746 injection moulding Methods 0.000 description 2
- 238000010030 laminating Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- 229910052582 BN Inorganic materials 0.000 description 1
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000002266 amputation Methods 0.000 description 1
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 239000002775 capsule Substances 0.000 description 1
- 239000003575 carbonaceous material Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000007721 mold pressing method Methods 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000011226 reinforced ceramic Substances 0.000 description 1
- 239000012744 reinforcing agent Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 238000000859 sublimation Methods 0.000 description 1
- 230000008022 sublimation Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、セラミックスの焼成に用いるカーボンヒータ
ーおよび、非酸化物系セラミックス原料粉末と焼結助剤
とよりなる粉末成形体を焼成炉中において不活性雰囲気
下に高温度に加熱することにより焼結するための、該カ
ーボンヒーターを用いた焼成炉に関する。Detailed Description of the Invention (Industrial Field of Application) The present invention provides a carbon heater used for firing ceramics, and a powder compact made of a non-oxide ceramic raw material powder and a sintering aid in a firing furnace. The present invention relates to a firing furnace using the carbon heater for sintering by heating to high temperature in an inert atmosphere.
（従来の技術）
窒化物系セラミックス原料、例えば窒化珪素５ｉＪａあ
るいは窒化硼素ＢＮなどは難焼結性の物質であり、その
焼結°を促進するために焼結助剤としてＭｇＯやＡｌｔ
ｏｓなどの金属酸化物（Ｍｅｎ）あるいは金属酸化物と
金属窒化物との混合物を５〜１０％添加するのが一般的
であり、また焼結前の例えば５ｔ３Ｎ４成形体は通常４
０容量％程度の気孔を有している。ここで窒化珪素の強
度発現の機構は、焼結助剤として加えた金属酸化物のガ
ラス相中に補強剤としてのβ型の窒化珪素の針状結晶が
分散してなる一種の繊維補強セラミックス、すなわちＦ
ＲＣ（Ｆｉｂｅｒ Ｒｅ１ｎｆｏｒｃｅｄ Ｃｅｒａｍ
ｉｃｓ）が形成されることによって優れた強度特性が発
現するとされている。(Prior art) Nitride-based ceramic raw materials, such as silicon nitride 5iJa or boron nitride BN, are difficult to sinter, and MgO or Al is used as a sintering aid to promote sintering.
It is common to add 5 to 10% of a metal oxide (Men) such as os or a mixture of a metal oxide and a metal nitride, and for example, a 5t3N4 molded body before sintering usually has a
It has pores of about 0% by volume. Here, the mechanism of the strength development of silicon nitride is that it is a type of fiber-reinforced ceramic in which acicular crystals of β-type silicon nitride as a reinforcing agent are dispersed in a glass phase of a metal oxide added as a sintering aid. That is, F
RC (Fiber Reinforced Ceram)
It is said that excellent strength properties are developed by the formation of ics).
さらに５ＩｘＮａを例にとれば、かかる成形体は一般に
高温不活性雰囲気中、特に窒素ガス雰囲気下１７００°
Ｃ〜１９００°Ｃの温度で焼成される。このような高温
度を不活性雲囲気下で安定的に維持するための典型的焼
成炉は、成形体収容空間と該空間の周囲に配設されたカ
ーボンヒーターと内壁面を被覆する炭素繊維マットより
なる断熱層とを内蔵してなる。炭素繊維マットは断熱性
を良好にするために極めて気孔率が大きく平均的０．２
ｇ／ｃｃ前後の嵩密度を有する。ところが高温焼成中に
金属酸化物を含有するＳｉ３Ｎ、成形体から発生する微
量の酸素、酸化物あるいは酸窒化物と高温下で接触した
マット表層の炭素繊維は酸化作用を受けるので、少しず
つではあるが剥落する。剥落した炭素繊維塵は炉内に飛
散・浮遊し、焼結前または焼結中の気孔率の高いＳｉ：
＋Ｌ成形体に付着して焼結による成形体の収縮時にその
内部に取り込まれることが起こり得る。炭素は、焼結助
剤である金属酸化物と反応し、ＣＯあるいはＣＯ□とな
って炉内に飛び出してゆき、それと同時に金属酸化物は
還元され低融点の金属となり蒸散するためガラス相マト
リックスを形成する筈の金属酸化物は、特に表面層にお
いて失われ、ＳｉＪ、のスケルトンが残ることとなる。Further, taking 5IxNa as an example, such molded bodies are generally heated at 1700° in a high temperature inert atmosphere, particularly in a nitrogen gas atmosphere.
It is fired at a temperature of 1900°C to 1900°C. A typical firing furnace for stably maintaining such a high temperature under an inert cloud atmosphere consists of a compact housing space, a carbon heater placed around the space, and a carbon fiber mat covering the inner wall surface. It has a built-in heat insulating layer. Carbon fiber mats have extremely high porosity with an average of 0.2 to provide good insulation.
It has a bulk density of around g/cc. However, the carbon fibers in the surface layer of the mat that come into contact with Si3N containing metal oxides during high-temperature firing and trace amounts of oxygen, oxides, or oxynitrides generated from the molded body at high temperatures are subject to oxidation, so the peels off. The flaked carbon fiber dust scatters and floats in the furnace, and the Si with high porosity is removed before or during sintering.
+L It is possible that it adheres to the molded body and is taken into the inside of the molded body when the molded body contracts due to sintering. Carbon reacts with the metal oxide, which is a sintering aid, and becomes CO or CO□, which escapes into the furnace. At the same time, the metal oxide is reduced and becomes a low-melting-point metal, which evaporates, leaving the glass phase matrix. The metal oxide that would have been formed is lost, especially in the surface layer, leaving behind a skeleton of SiJ.
スケルトンの状態ではＳｉ、Ｎ、焼結体は最早や高強度
、高耐熱衝撃性、耐摩耗性などの特性を有しない。In the skeleton state, Si, N, and sintered bodies no longer have characteristics such as high strength, high thermal shock resistance, and high wear resistance.
また、炉内で発生したＣｏ、 ＣＯ２などが５ｉＪａ成
形体に触れることで次のような反応を繰り返し、金属酸
化物（Ｍｅ（１）は急速に失われる。Furthermore, when Co, CO2, etc. generated in the furnace come into contact with the 5iJa compact, the following reactions occur repeatedly, and the metal oxide (Me(1)) is rapidly lost.
Ｓｔ、Ｎｎ ＋ ＭｅＯ＋ Ｃｏ →Ｓｉ３Ｎ４＋ Ｃ
Ｏ，＋Ｍｅ ↑ＣＯ！→ＣＯ＋Ｏ
Ｃ＋０→Ｃ０
これによっても上述の５ｉＪ４スケルトンの生成が促進
される。St, Nn + MeO+ Co → Si3N4+ C
O, +Me ↑CO! →CO+O C+0→C0 This also promotes the generation of the above-mentioned 5iJ4 skeleton.
このような断熱層を形成する炭素繊維がほぐれて炭素繊
維塵となって飛散することによる成形体表面への悪影響
を防止し、高強度にして耐摩耗性、熱衝撃抵抗性に優れ
た高品質の５ｉＪ４焼結体を提供するために、本発明者
は塁に、灰分０．３重量％以下のグラファイト薄片を積
層成形してなるシートを炭素繊維マットからなる断熱層
と成形体との間に介在せしめて断熱層より離脱し浮遊す
る炭素繊維塵と成形体との接触を遮断することからなる
高品質窒化珪素焼結体の製造方法を提案した。This prevents the carbon fibers that form the heat insulating layer from unraveling and scattering as carbon fiber dust, which would have an adverse effect on the surface of the molded product, making it a high-quality product with high strength and excellent abrasion resistance and thermal shock resistance. In order to provide a 5iJ4 sintered body of We have proposed a method for manufacturing high-quality silicon nitride sintered bodies, which involves intervening the carbon fiber dust that separates from the heat insulating layer and blocks contact between the molded body and the carbon fiber dust floating thereon.
（発明が解決しようとする問題点）
上記本発明者の嚢の提案により前述せる従来の問題点は
大幅に解決の方向に向かったが、ファインセラミックス
の急速な発展と用途拡大に伴う高性能および高品質化の
要求に応えるには尚十分とは言い難かった。(Problems to be Solved by the Invention) The above-mentioned conventional problems have been largely solved by the inventor's proposal of the capsule, but with the rapid development of fine ceramics and the expansion of their applications, high performance and It was still not enough to meet the demands for higher quality.
そこで本発明者は残存する問題点の探究と原因の究明に
引続き努力を重ねた結果、カーボンヒーターの材質と窒
化物系セラミックス焼結体の品質との間に密接な相関関
係があり、相互に作用し合うことを知見した。すなわち
従来のカーボンヒーターはその発熱性能を満足する範囲
で極力安価に製作することに主眼がおかれていたため、
構成素材であるグラファイトの純度に対してはさほどの
配慮をなすことなく、通常、炭素含量スリーナイン程度
で、珪素、鉄等の不純物含量も数百ｐｐｍ程度のものが
用いられてきた。ところがかかるカーボンヒーターは、
高温加熱時にそのグラファイトが、含有する珪素あるい
は鉄分などの不純物部位を起点として侵食穿孔が始まり
、炭素が崩壊・飛散して焼結前または焼結中の窒化物成
形体に付着して前述同様に焼結体の表面層のスケルトン
化をもたらす。それと同時に成形体より発生する酸素、
酸化物あるいは窒酸化物は逆にヒーターのグラファイト
に形成された細孔中に侵入し、内奥部の炭素と反応して
グラファイトの骨諮を蚕食崩壊し、炭素粒子を放出しつ
つ、さらに洞孔を拡げ、遂にはヒータ一部材に蟻の巣状
の穴を形成する。かくして放散炭素による焼結体の表層
スケルトン化はさらに増進するとともにヒーターの劣化
が加速される。かかるヒーターは、ヒーター材としての
相バランスを崩し正確な温度制御を不能とするのみなら
ず、多孔質化した部分では表面電流が局部的に増大し、
甚だしい場合は切断するに至る。Therefore, as a result of continued efforts to investigate the remaining problems and investigate the causes, the present inventor found that there is a close correlation between the material of the carbon heater and the quality of the nitride ceramic sintered body. We found that they interact. In other words, the main focus of conventional carbon heaters was to manufacture them as inexpensively as possible while still satisfying their heat generation performance.
Without paying much attention to the purity of graphite, which is a constituent material, graphite having a carbon content of about three nines and a content of impurities such as silicon and iron of about several hundred ppm has been used. However, the carbon heater that takes
During high-temperature heating, the graphite begins to erode and perforate starting from impurity sites such as silicon or iron, and the carbon collapses and scatters, adhering to the nitride compact before or during sintering, resulting in the same phenomenon as described above. This results in skeletonization of the surface layer of the sintered body. At the same time, oxygen generated from the molded object,
Oxides or nitrides, on the other hand, penetrate into the pores formed in the graphite of the heater, react with the carbon deep inside, destroy the graphite bones, release carbon particles, and further penetrate the pores. The hole is enlarged, and an ant nest-like hole is finally formed in the heater member. In this way, the skeletonization of the surface layer of the sintered body due to the emitted carbon is further promoted and the deterioration of the heater is accelerated. Such a heater not only destroys the phase balance of the heater material and makes accurate temperature control impossible, but also causes a local increase in surface current in porous parts.
In severe cases, amputation may be necessary.
また上述の現象の他に、重要な温度制御機能を掌る熱電
対に与える浮遊炭素粒子の悪影響の問題があらためて認
識された。すなわち１７００〜２０００°Ｃの高温窒素
ガス雰囲気中の温度測定には、高温に対して通常適用さ
れる二色温度計は炉内ガスの対流による揺らぎなどによ
り正確を期し難い。従って、Ｗ／Ｒｅ熱電対を、窒素ガ
スによるタングステンの窒化防止のために典型的にはア
ルゴンガスを封入したモリブデン保護管中に組み込んで
使用することが一般的である。ところが、モリブデン保
護管は、浮遊炭素粒子が付着すると炭化され、非常に脆
くまた熱膨張係数がＭｏと異なるＭｏＣとなるため数回
の焼成作業後クランクが入り、封入アルゴンガスが漏出
して窒素ガスが侵入する。それによりタングステンは窒
化されＷ／Ｒｅ熱電対は起電力が変化して正確な機能を
喪失することとなる。In addition to the above-mentioned phenomena, the problem of the negative effects of suspended carbon particles on thermocouples, which perform important temperature control functions, has been recognized. That is, when measuring temperature in a high-temperature nitrogen gas atmosphere of 1,700 to 2,000°C, it is difficult to ensure accuracy with a two-color thermometer that is normally applied to high temperatures due to fluctuations caused by convection of gas in the furnace. Therefore, it is common to use a W/Re thermocouple by incorporating it into a molybdenum protection tube typically filled with argon gas to prevent nitridation of tungsten by nitrogen gas. However, when floating carbon particles adhere to the molybdenum protection tube, it becomes carbonized and becomes MoC, which is extremely brittle and has a coefficient of thermal expansion different from that of Mo. Therefore, when the molybdenum protection tube is cranked after several firing operations, the enclosed argon gas leaks out and nitrogen gas is released. invades. As a result, tungsten is nitrided, and the electromotive force of the W/Re thermocouple changes, causing it to lose its correct function.
本発明は、上述の種々の問題点を一挙に解決に導くため
になされたもので、その主要な目的は、高強度にして耐
摩耗性、耐熱衝撃性に著しく優れた高品質の非酸化物系
セラミックス焼結体、特にＳｉ、Ｎ、焼結体を提供する
にある。The present invention was made to solve the above-mentioned various problems all at once, and its main purpose is to produce a high-quality non-oxide material with high strength and excellent wear resistance and thermal shock resistance. The purpose of the present invention is to provide a ceramic sintered body, particularly a Si, N, ceramic sintered body.
他の目的は、カーボンヒーターの劣化を防止しその耐用
命数を延長せんとするにある。Another purpose is to prevent deterioration of the carbon heater and extend its service life.
更に他の目的は、焼成時の正確な温度制御を長期間持続
することにある。Yet another objective is to maintain accurate temperature control during firing for a long period of time.
（問題点を解決するための手段）
上述の目的を達成するための本発明になるカーボンヒー
ターは炭素含量が９９．９９８０％（重量）以上、珪素
含量が５ｐｐｍ（重Ｎ）以下、鉄分含量が９ｐｐＨｌ（
重量）以下の高純度グラファイトよりなることを特徴と
するもので、また該ヒーターを用いたセラミックス焼結
用の焼成炉は、非酸化物系セラミックス原料粉末と焼結
助剤とよりなる粉末成形体を焼成炉中において不活性雰
囲気下にカーボンヒーターを用いて高温度に加熱するこ
とにより焼結するに際し、前記カーボンヒーター素材と
して炭素含量９９．９９８０％（重量）以上、珪素含量
５ｐｐｍ（重量）以下、鉄分含量９ｐｐｍ（重量）以下
のの高純度グラファイトを適用することにより、炉内雰
囲気を清浄に保持することを特徴とするセラミックス焼
結用焼成炉である。(Means for Solving the Problems) The carbon heater according to the present invention to achieve the above-mentioned objects has a carbon content of 99.9980% (weight) or more, a silicon content of 5 ppm (heavy N) or less, and an iron content of 9ppHl(
The heater is characterized by being made of high-purity graphite with a weight of less than When sintering by heating to high temperature using a carbon heater in an inert atmosphere in a firing furnace, the carbon heater material has a carbon content of 99.9980% (weight) or more and a silicon content of 5 ppm (weight) or less. This is a firing furnace for sintering ceramics, characterized in that the atmosphere inside the furnace is kept clean by applying high-purity graphite with an iron content of 9 ppm (weight) or less.
本発明を最も好適に適用し得る非酸化物系セラミックス
は窒化珪素である。The non-oxide ceramic to which the present invention can be most suitably applied is silicon nitride.
本発明に適用する高純度グラファイトは、好ましくは９
９．９９８５％（重量）以上、さらに好ましくは９９．
９９９５％（重量）以上の炭素含量を有し、また好まし
くは４ｐｐｍ（重量）以下、さ゛らに好ましくは２ｐｐ
ｍ（重量）以下の珪素含量を有し、さらにまた、好まし
くは８ｐｐｍ（重量）以下、さらに好ましくは３ｐｐｍ
（重量）以下の鉄分含量を有する。The high purity graphite applied to the present invention is preferably 9
9.9985% (weight) or more, more preferably 99.985% (weight) or more.
It has a carbon content of 9995% (by weight) or more, and preferably 4 ppm (by weight) or less, and even more preferably 2 ppm (by weight).
m (by weight) or less, further preferably 8 ppm (by weight) or less, more preferably 3 ppm
(by weight) with iron content below.
また本発明に適用する高純度グラファイトは好ましくは
少なくとも１．７５ ｇ／ｃｃ、さらに好ましくは１．
７６ ｇ／ｃｃの嵩密度を有する。Further, the high purity graphite applied to the present invention preferably has a particle size of at least 1.75 g/cc, more preferably 1.75 g/cc.
It has a bulk density of 76 g/cc.
本発明における不活性雰囲気として好適なものは窒素ガ
ス雰囲気であり、加圧下に適用することが最も好ましい
。A suitable inert atmosphere in the present invention is a nitrogen gas atmosphere, most preferably applied under pressure.
本発明は、炭素繊維マットよりなる断熱層で囲繞された
高温不活性雰囲気中において焼結作業を行なう際には、
本発明者が別途提案した方法、すなわち、灰分０．３重
量％以下のグラファイト薄片を積層成形してなるシート
を上記断熱層と成形体との間に介在せしめて断熱層と成
形体とを遮断する方法と併用すれば最良の結果が得られ
る。In the present invention, when performing sintering work in a high temperature inert atmosphere surrounded by a heat insulating layer made of carbon fiber mat,
A method separately proposed by the present inventor is that a sheet formed by laminating and molding graphite flakes with an ash content of 0.3% by weight or less is interposed between the above-mentioned heat insulating layer and the molded body to isolate the heat insulating layer and the molded body. Best results can be obtained when used in conjunction with other methods.
カーボンヒーターの素材であるグラファイトとしては、
従来コークスなどの粉砕物にピッチなどを加えた炭素材
料を混練してペースト状となし、押出しまたは射出成形
によって棒状構造としたものを焼成してグラファイト化
を行ない所望形状とするのが一般的である。かかるグラ
ファイト部材は最も廉価に製造し得てかつ所要の高温度
を達成する十分な能力を具えるために広く慣用されてき
たが、珪素および鉄を含む灰分量が多く、さらに密度も
約１．６５ ｇ／ｃｃと小さく、それらが前述の問題点
の主因をなしていた。Graphite, which is the material for carbon heaters, is
Conventionally, it has been common practice to knead a carbon material such as coke with pitch added to form a paste, form a rod-like structure by extrusion or injection molding, and then sinter it to graphitize it into the desired shape. be. Such graphite members have been widely used because they are the cheapest to manufacture and have sufficient ability to achieve the required high temperatures, but they have a high ash content, including silicon and iron, and a density of about 1. As small as 65 g/cc, they were the main cause of the above-mentioned problems.
本発明に適用されるカーボンヒーター素材としてのグラ
ファイト部材は、押出成形や射出成形などの異方成形に
よらず、金型プレス法、さらに好ましくは冷間等方加圧
プレス（ＣＩＰ）法により等方的に成形した母材を、常
法に従い焼成して黒鉛化したうえ、不活性雰囲気中にハ
ロゲンガスを導入して加熱し不純物を除去する高純度化
処理を施したものが好適である。The graphite member as a carbon heater material applied to the present invention is not produced by anisotropic molding such as extrusion molding or injection molding, but by mold pressing method, more preferably cold isostatic pressing (CIP) method. It is preferable that a squarely shaped base material is fired and graphitized according to a conventional method, and then subjected to a purification treatment in which halogen gas is introduced into an inert atmosphere and heated to remove impurities.
上述の方法で得られた、炭素含量中なくとも９９．９９
８０％（重量）、このましくは少なくとも９９．９９８
５％（重量）、さらに好ましくは少なくとも９９．９９
９５％（重量）で、不純物のうち珪素含量が５ｐｐｍ（
重量）以下、好ましくは４ｐｐｍ（重量）以下、さらに
好ましくは２ｐｐｍ（重Ｍ）以下、また鉄分含有量が９
ｐｐｍ（重量）以下、好ましくは８ ｐｐｍ（重量）以
下、さらに好ましくは３ｐｐｍ（重量）以下のグラファ
イト部材を本発明のカーボンヒーターの素材として適用
する。炭素含量が９９．９９８０％（重量）未満で珪素
含量が５ｐｐｍ（重量）超および鉄分含量が９ｐｐｍ（
重量）超となると、焼結体の表面強度、耐酸化特性の向
上が殆ど認められず、またヒーター寿命の長期化、熱電
対の劣化防止も実質的に達成されない。また前述の等方
的成形方法によって密度１．７５ｇ／ｃｃ以上のグラフ
ァイト部材とすることが可能であり、かかる密度のもの
が本発明ヒーター素材としては望ましい。密度が過小で
あるとグラファイトの分子間に酸素、酸化物等が侵入す
る機会が増えるため好ましくない。obtained by the method described above, with a carbon content of at least 99.99
80% (by weight), preferably at least 99.998
5% (by weight), more preferably at least 99.99
95% (by weight), silicon content of impurities is 5 ppm (
weight) or less, preferably 4 ppm (weight) or less, more preferably 2 ppm (weight M) or less, and the iron content is 9
A graphite member having a content of ppm (weight) or less, preferably 8 ppm (weight) or less, and more preferably 3 ppm (weight) or less is used as a material for the carbon heater of the present invention. The carbon content is less than 99.9980% (by weight), the silicon content is more than 5 ppm (by weight) and the iron content is 9 ppm (by weight).
Weight), the surface strength and oxidation resistance of the sintered body will hardly be improved, and the life of the heater will not be extended and the deterioration of the thermocouple will not be substantially prevented. Further, it is possible to obtain a graphite member having a density of 1.75 g/cc or more by the above-mentioned isotropic molding method, and a material having such a density is desirable as the heater material of the present invention. If the density is too low, there is an increased chance that oxygen, oxides, etc. will enter between graphite molecules, which is undesirable.
かかる高純度グラファイトを素材とするカーボンヒータ
ーは窒化物系セラミックスのみならず、炭化物系などの
非酸化物系セラミックスの焼成炉用ヒーターとして好適
であり、さらにＳｔ単結晶成長炉のヒーターなどにも有
利に適用可能である。Carbon heaters made of such high-purity graphite are suitable as heaters for firing furnaces not only for nitride ceramics but also for non-oxide ceramics such as carbides, and are also advantageous for heaters for St single crystal growth furnaces. Applicable to
焼成炉の内壁面に炭素繊維をもってマット状に成形した
断熱層を添設しである場合には、焼成される成形体と断
熱層との間にグラファイトシートをくまなく一様に介在
せしめ、成形体を取り巻く雰囲気と断熱層近傍に沿った
雰囲気との自由な流通を遮断したうえで、本発明を適用
することが最も望ましい。If a heat insulating layer made of carbon fibers formed into a mat shape is attached to the inner wall of the firing furnace, a graphite sheet is uniformly interposed between the molded body to be fired and the heat insulating layer, and the molding It is most desirable to apply the present invention after blocking free flow between the atmosphere surrounding the body and the atmosphere along the vicinity of the heat insulating layer.
上記グラファイトシートは高純度のグラファイト薄片を
積層成形してなるもので、それ自体から高温下に発生す
る不純物を最小限に抑えるため、灰分量を０．３重量％
以下、好ましくは０．２重量％以下、さらに好ましくは
０．１重量％以下となした高純度化処理グラファイトを
以て形成される。かかるシートは窒素ガス雰囲気下少な
くとも約２５００°Ｃの温度に十分堪えることができる
。The above graphite sheet is made by laminating and molding high-purity graphite flakes, and the ash content is 0.3% by weight in order to minimize impurities generated from the sheet itself at high temperatures.
Hereinafter, it is formed using highly purified graphite containing preferably 0.2% by weight or less, more preferably 0.1% by weight or less. Such sheets are capable of withstanding temperatures of at least about 2500°C under a nitrogen gas atmosphere.
シートの厚さは約０．２ｍｍ〜０．４ｍｍであることが
好ましく余り薄過ぎると強度が不足し添設、張設時に破
断のおそれが生じ、一方厚過ぎると加工性が低下するの
で好ましくない。The thickness of the sheet is preferably about 0.2 mm to 0.4 mm. If it is too thin, the strength will be insufficient and there is a risk of breakage when attached or stretched, while if it is too thick, the workability will decrease, which is not preferable. .
前述の高純度グラファイトをカーボンヒーター素材とし
て適用することにより、グラファイト自身の崩壊、穿孔
などによる炭素の遊離、飛散は著しく減少し、炉内雰囲
気を頗る清浄に保持することができる。By using the above-mentioned high-purity graphite as the carbon heater material, the release and scattering of carbon due to the disintegration and perforation of the graphite itself is significantly reduced, and the atmosphere inside the furnace can be kept extremely clean.
（作 用）
常法により金属酸化物焼結助剤を加えた５ｉＪｎまたは
ＢＮなどの窒化物粉末を金型成形またはラバープレスな
どの冷間等方加圧プレスにより成形した成形体を焼成炉
中に装入し、炉内雰囲気を不活性ガス、特に窒素ガスに
置換したうえ、必要に応じさらにガス分圧を上げる。そ
の状態でカーボンヒーターに電圧を印加し、炉内温度を
約１７００°Ｃ以上、窒化物の昇華温度未満、通常約１
８００°Ｃ位まで昇温し、その温度に約１時間保持して
焼成する。(Function) A compact formed by molding nitride powder such as 5iJn or BN to which a metal oxide sintering aid has been added by a conventional method or by cold isostatic pressing such as a rubber press is placed in a firing furnace. After replacing the atmosphere in the furnace with an inert gas, especially nitrogen gas, the gas partial pressure is further increased as necessary. In this state, a voltage is applied to the carbon heater to raise the furnace temperature to about 1700°C or higher, below the sublimation temperature of nitride, usually about 1
The temperature is raised to about 800°C and kept at that temperature for about 1 hour for firing.
本発明においては、カーボンヒーター素材として炭素含
量が極めて高くかつ不純物が頗る少ない高純度グラファ
イトを使用したことにより、高温焼成中、グラファイト
からの炭素粒子の遊離・飛散が著しく減少するから、ヒ
ーターのグラファイト自体の蟻の巣状穿孔は殆ど防止さ
れるとともに、成形体と接触する炉内雰囲気は炭素粒子
が著しく減少した清浄状態に保たれる。そのため成形体
の炭素取り込みによる焼結助剤の減耗は防止され、窒化
物のスケルトン化も著しく低減し、表層まで窒化物針状
結晶が焼結助剤のガラス質中に均一に分散した良質の窒
化物系焼結体が得られる。また焼成中の成形体からの酸
素、酸化物等のガス発生が大幅に抑制されることにより
、グラファイトの侵食を誘発することが実質的に無くな
り、極く微量発生したそれらのガスが緻密なグラファイ
トの表面に接触しても内奥部に侵入し得ないからグラフ
ァイトの骨賂の崩壊が減少し、ヒーターは良好な状態を
長期間維持することができる。In the present invention, by using high-purity graphite with an extremely high carbon content and very few impurities as the carbon heater material, the release and scattering of carbon particles from the graphite during high-temperature firing is significantly reduced. Ant nest-like perforation of the molded body is almost prevented, and the atmosphere in the furnace in contact with the molded body is maintained in a clean state in which carbon particles are significantly reduced. As a result, the depletion of the sintering aid due to carbon incorporation into the compact is prevented, and skeletonization of nitride is also significantly reduced, resulting in a high-quality product with nitride needle crystals uniformly dispersed in the glassy material of the sintering aid up to the surface layer. A nitride-based sintered body is obtained. In addition, by greatly suppressing the generation of gases such as oxygen and oxides from the compact during firing, it is virtually impossible to induce corrosion of graphite, and the extremely small amount of gases generated can form a dense graphite structure. Even if it comes into contact with the surface of the heater, it cannot penetrate deep inside the heater, which reduces the collapse of the graphite bone and allows the heater to maintain good condition for a long period of time.
（実施例）
上記本発明を実施例について説明する。実施例中の「パ
ーセント」および「部」はすべて重量基準である。(Example) The above-mentioned present invention will be described with reference to an example. All "percents" and "parts" in the examples are based on weight.
尖翳尉
カーボンヒーター劣化の原因としては、従来、雰囲気ガ
ス中に含まれる酸素の作用によるものと考えられていた
ため、それを確認するため次の実験を行なった。The cause of carbon heater deterioration was previously thought to be due to the action of oxygen contained in the atmospheric gas, so the following experiment was conducted to confirm this.
雰囲気ガスとして窒素ガスを選び、微量の酸素を混入し
て純度９９．９９９％および９９．９０％の二種類の窒
素ガスを用意した。それぞれの窒素ガスを用いて約■８
００°ＣＳ １時間の加熱を１００回反覆したが、両者
ともカーボン劣化の状態に有意差を認めなかった。Nitrogen gas was selected as the atmospheric gas, and a trace amount of oxygen was mixed to prepare two types of nitrogen gases with purity of 99.999% and 99.90%. About ■8 using each nitrogen gas
Heating at 00°C for 1 hour was repeated 100 times, but no significant difference was observed in the state of carbon deterioration in both cases.
実力Ｕ
ＳｉｉＮ４原料粉末９０％、５ｒ（ｈ １％、Ｍｇ０４
％およびＣｅＯ□５％を混合し、金型プレス機にて６ｍ
ｍＸ６０ｍｍＸ６０ｍｍの角板に成形したＳｉ３Ｎ４成
形体を試料とした。このものを内径４００ｎｎｎφ、高
さ１００１００Ｏの焼成炉に装入し、窒素ガス分圧１ａ
ｔｍ、、 １７００°Ｃに１時間保持して焼成した。Ability U SiiN4 raw material powder 90%, 5r (h 1%, Mg04
% and CeO
The sample was a Si3N4 molded body formed into a square plate of m x 60 mm x 60 mm. This material was charged into a firing furnace with an inner diameter of 400nnnφ and a height of 100100O, and the nitrogen gas partial pressure was 1a.
tm, It was held at 1700°C for 1 hour and fired.
この際、カーボンヒーターのグラファイトとして第１表
に示す６種類を用意した。なお、不純物元素は原子吸光
法によって測定した。At this time, six types of graphite shown in Table 1 were prepared as graphite for the carbon heater. Note that impurity elements were measured by atomic absorption spectrometry.
各ヒーターを用いて行なった焼結体特性調査の結果を第
２表に示す。Table 2 shows the results of the sintered body characteristics investigation conducted using each heater.
本１０００”Ｃで１０００時間、空気中で加熱した後の
単位面積当り重量増加
本章 ザイグロ法により蛍光剤有機溶剤溶液に浸漬後
、水洗し、滲出程度をブラックライトランプで観察した
評価段階二〇・・・殆ど認めず
Δ・・・斑点状に滲出
×・・・全面に滲出
第２表の結果から明らかな通り、本発明によって得られ
たＳｉＪ、焼結体は従来品に較べて、焼成面の曲げ強さ
が極めて大である。また高温酸化作用に対しても著しく
安定でであり、蛍光探傷によって緻密でボイドの少ない
組織であることが例証され、耐摩耗性および耐熱衝撃性
に優れていることが判る。Weight increase per unit area after heating in air at 1000"C for 1000 hours This chapter Evaluation stage 20: After immersing in a fluorescent agent organic solvent solution using the Zygro method, washing with water, and observing the degree of exudation with a black light lamp. ...Hardly observed Δ...Leaked in spots ×...Leaked all over the surface As is clear from the results in Table 2, the SiJ sintered body obtained by the present invention has a lower firing surface than the conventional product. It has extremely high bending strength. It is also extremely stable against high-temperature oxidation, and fluorescent flaw detection has demonstrated that it has a dense structure with few voids, and it has excellent wear resistance and thermal shock resistance. I know that there is.
特にヒータ一番号０を用いた比較例１によって傅られた
Ｓｉ３Ｎ４焼結体は表面が白色を呈し、表面から数ミリ
メートル内部は黒灰色になるという色相差が認められ、
表面層がスケルトン化していた。In particular, the Si3N4 sintered body obtained in Comparative Example 1 using heater No. 1 had a white color on the surface, and a hue difference was observed in which the inside a few millimeters from the surface became blackish gray.
The surface layer had become skeletonized.
さらに本発明に適用するカーボンヒーターのグラファイ
トの炭素および不純物含有量は焼結体の特性値に対して
有意な作用があることが判明した。Furthermore, it has been found that the carbon and impurity contents of the graphite of the carbon heater applied to the present invention have a significant effect on the characteristic values of the sintered body.
実施陥ｌ二刊
焼成時の窒素ガス分圧を１０ａ ｔｍとし、焼成温度を
１７５０°Ｃとする以外はすべて前記比較例および実施
例と同様にしてＳｉ３Ｎ４焼結体を得た。その試験結果
を第３表に示す。Example 1 A Si3N4 sintered body was obtained in the same manner as in the Comparative Example and Example except that the nitrogen gas partial pressure during the second firing was 10 atm and the firing temperature was 1750°C. The test results are shown in Table 3.
第３表
第３表の結果を第２表と対比すれば明らかな通り、雰囲
気窒素ガス分圧を上げて焼成温度を上昇させた方が焼結
体の強度がさらに向上する。Table 3 As is clear from comparing the results in Table 3 with Table 2, the strength of the sintered body is further improved by increasing the atmospheric nitrogen gas partial pressure and increasing the firing temperature.
災施■旦二長
第１表に示した６種類のグラファイトをヒーター素材と
するカーボンヒーターを用い、窒素ガス分圧１０ ａｔ
ｍ、焼成温度１８００″Ｃ１焼成時間１時間という条件
でＳｉ３Ｎ、の焼成を反覆し、ヒーターおよび熱電対の
耐久性を調べた。その結果は第４表の通りであった。Using a carbon heater made of six types of graphite shown in Table 1, the partial pressure of nitrogen gas was 10 at.
The durability of the heater and thermocouple was investigated by repeating the firing of Si3N under the following conditions: m, firing temperature: 180''C1 firing time: 1 hour.The results are shown in Table 4.
第４表
３１１Ｏ以上 ３５
４１１０以上 ３５
５１５０以上 ４０
第４表の結果から、本発明は、カーボンヒーター自体の
耐用命数ならびに熱電対の機能維持月間を従来より著し
く延長する効果をも奏することが首肯される。Table 4 311O or more 35 4110 or more 35 5150 or more 40 From the results shown in Table 4, it is confirmed that the present invention has the effect of significantly extending the service life of the carbon heater itself and the functional maintenance period of the thermocouple compared to the conventional method. Ru.
（発明の効果）
上述の通り、本発明によれば、非酸化物系セラミックス
、特にＳｉ、Ｎ、セラミックス焼成時に焼成炉内雰囲気
は、カーボンヒーターから発生する炭素粒子による汚染
が減少して清浄に保たれるため、焼結体表面の焼結助剤
の減耗によるＳｉ、Ｎ、スケルトン化が防止され、高強
度にして耐摩耗性、熱衝撃抵抗性に優れ、均質且つ高品
質のＳｉ３Ｎ４焼結体が得られる。このような品質・性
能の向上によって窒化物系セラミックスの応用範囲の一
層の拡大が期待される。(Effects of the Invention) As described above, according to the present invention, when non-oxide ceramics, especially Si, N, and ceramics are fired, the atmosphere inside the firing furnace is cleaned by reducing contamination by carbon particles generated from the carbon heater. This prevents Si, N, and skeletonization due to depletion of the sintering aid on the surface of the sintered body, resulting in homogeneous and high-quality Si3N4 sintering with high strength, excellent wear resistance, and thermal shock resistance. You get a body. Such improvements in quality and performance are expected to further expand the range of applications for nitride ceramics.
また、本発明によって高価なヒーターおよびＷ／Ｒｅ熱
電対の耐用命数が延長され良好な機能が長期間維持され
るので、交換頻度減少に伴う経費の節約と、製造条件の
安定化による品質の均一化という一石二鳥の効果に加え
、連続量産を可能となした経済的利点は大きい。In addition, the present invention extends the service life of expensive heaters and W/Re thermocouples and maintains good functionality for a long period of time, resulting in cost savings due to reduced replacement frequency and uniform quality due to stable manufacturing conditions. In addition to the ability to kill two birds with one stone, the economic benefits of making continuous mass production possible are significant.
特許出願人 日本碍子株式会社
手 続 補 正 占
昭和６３年 ６月 ８日
特許庁長官 小 川 邦 夫 殴ｌ、事件
の表示
昭和６２年特許 別箇 １３４９６０ 号２、発明の
名称
３、補正をする者
事件との関係 特許出願人
４、代理人
１、明細書第２０頁第１３行目の「首肯される。」の次
に、改行して下記の文を挿入する。Patent applicant: Nippon Insulators Co., Ltd. Procedures Amendment: June 8, 1988 Director-General of the Patent Office Kunio Ogawa, Indication of the case: 1988 Patent Separate Clause 134960 No. 2, Name of the invention 3, Amendments made Patent Applicant 4, Agent 1, page 20, line 13 of the specification, after "Approved", insert the following sentence on a new line.
’ Ｓｉ３Ｎ、を焼結するに当っては、成形体をＳｉ
Ｃ製るつぼ、Ｓｉ：＋Ｎ４製るつぼ、あるいは表面にＳ
ｉＣが緻密に蒸着されたカーボンるつぼなどの中に収納
し、焼成することが一般的である。' When sintering Si3N, the molded body is
Crucible made of C, Si:+N4 crucible, or S on the surface
Generally, it is stored in a carbon crucible or the like in which iC is densely deposited, and fired.
これは、炉内に存在する断熱材カーボンファイバーくず
の影響を抑える効果、あるいはヒーター材の分解に起因
するＣＯやＣＯ２などのガスの影ピを抑える効果などが
あるためであり、更に幾何学的に組み立てて焼結体を効
率よく焼成する役割を果たす。This is because it has the effect of suppressing the influence of the heat insulating carbon fiber waste existing in the furnace, and the effect of suppressing the shadow of gases such as CO and CO2 caused by the decomposition of the heater material. It plays the role of efficiently firing the sintered body by assembling the sintered body.
こうしたるつぼを使用する場合においても本発明は同様
の効果を奏することは言うまでもない。It goes without saying that the present invention produces similar effects even when such a crucible is used.
更にるつぼがＳｉ３Ｎ、などの場合には、るつぼのスケ
ルトン化を防止し、寿命を長くする点で効果があること
も付記する。」Furthermore, it should be noted that when the crucible is made of Si3N, etc., it is effective in preventing skeletonization of the crucible and extending its life. ”
Claims (1)
量が５ｐｐｍ（重量）以下、鉄分含量が９ｐｐｍ（重量
）以下の高純度グラファイトよりなることを特徴とする
セラミックスの焼成に用いるカーボンヒーター。 ２、嵩密度が少なくとも１．７５ｇ／ｃｃである特許請
求の範囲第１項記載のカーボンヒーター。 ３、非酸化物系セラミックス原料粉末と焼結助剤とより
なる粉末成形体を焼成炉中において不活性雰囲気下にカ
ーボンヒーターを用いて高温度に加熱することにより焼
結するに際し、前記カーボンヒーター素材として炭素含
量 ９９．９９８０％（重量）以上、珪素含量５ｐｐｍ（重
量）以下、鉄分含量９ｐｐｍ（重量）以下のの高純度グ
ラファイトを適用することにより、炉内雰囲気を清浄に
保持することを特徴とするセラ ミックス焼結用焼成炉 ４、非酸化物系セラミックスが窒化珪素である特許請求
の範囲第３項記載のセラミックス焼結用焼成炉[Claims] 1. A ceramic characterized by being made of high purity graphite having a carbon content of 99.9980% (weight) or more, a silicon content of 5 ppm (weight) or less, and an iron content of 9 ppm (weight) or less. Carbon heater used for firing. 2. The carbon heater according to claim 1, having a bulk density of at least 1.75 g/cc. 3. When sintering a powder compact made of a non-oxide ceramic raw material powder and a sintering aid by heating it to a high temperature using a carbon heater in an inert atmosphere in a firing furnace, the carbon heater The furnace atmosphere is kept clean by using high-purity graphite with a carbon content of 99.9980% (weight) or more, a silicon content of 5 ppm (weight) or less, and an iron content of 9 ppm (weight) or less as a material. A firing furnace 4 for sintering ceramics, and a firing furnace for sintering ceramics according to claim 3, wherein the non-oxide ceramic is silicon nitride.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13496087A JPS63301481A (en) | 1987-06-01 | 1987-06-01 | Carbon heater and ceramic sintering furnace using it |
| US07/180,064 US4912302A (en) | 1987-05-30 | 1988-04-11 | Furnace for sintering ceramics, carbon heater used therefor and process for sintering ceramics |
| EP88304636A EP0294066B1 (en) | 1987-05-30 | 1988-05-23 | Furnace for sintering ceramics and process for sintering ceramics |
| DE3852780T DE3852780T2 (en) | 1987-05-30 | 1988-05-23 | Sintering furnace for ceramics and method for sintering ceramics. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13496087A JPS63301481A (en) | 1987-06-01 | 1987-06-01 | Carbon heater and ceramic sintering furnace using it |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63301481A true JPS63301481A (en) | 1988-12-08 |
| JPH0423397B2 JPH0423397B2 (en) | 1992-04-22 |
Family
ID=15140603
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13496087A Granted JPS63301481A (en) | 1987-05-30 | 1987-06-01 | Carbon heater and ceramic sintering furnace using it |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63301481A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6627116B1 (en) | 1999-01-29 | 2003-09-30 | Mitsubishi Pencil Co., Ltd. | Carbon-based heating unit and method for preparation thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4492257B2 (en) * | 2004-08-26 | 2010-06-30 | 富士電機システムズ株式会社 | Semiconductor module and manufacturing method thereof |
-
1987
- 1987-06-01 JP JP13496087A patent/JPS63301481A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6627116B1 (en) | 1999-01-29 | 2003-09-30 | Mitsubishi Pencil Co., Ltd. | Carbon-based heating unit and method for preparation thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0423397B2 (en) | 1992-04-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR940011452B1 (en) | Silicon carbide refractories having modified silicon nitride bond | |
| HUE027172T2 (en) | Use of a sintered refractory material based on silicon carbide with a silicon nitride binder | |
| US5135893A (en) | Carbonaceous ceramic composite for use in contact with molten nonferrous metal | |
| US2691605A (en) | Silicon carbide articles and method of manufacturing same | |
| FR2727400A1 (en) | NEW MATERIALS IN THE FORMS OF REFRACTORY GRAINS BOUND BY A MATRIX OF ALUMINUM OR SIALON NITRIDE CONTAINING TITANIUM NITRIDE AND DISPERSED GRAPHITE AND / OR BORON NITRIDE PARTICLES | |
| EP0294066A2 (en) | Furnace for sintering ceramics and process for sintering ceramics | |
| Huang et al. | Sintering behaviour and properties of SiCAION ceramics | |
| Biswas et al. | Gas pressure sintering of SiC sintered with rare-earth-(III)-oxides and their mechanical properties | |
| JPS63301481A (en) | Carbon heater and ceramic sintering furnace using it | |
| CN111732417A (en) | Scouring-resistant ultra-low-carbon magnesia-carbon brick with excellent oxidation resistance and preparation method thereof | |
| Blugan et al. | Oxidation and corrosion of silicon nitride ceramics with different sintering additives at 1200 and 1500° C in air, water vapour, SO2 and HCl environments–A comparative study | |
| KR100332904B1 (en) | A Method for Manufacturing Carbon Cotaining Castable | |
| Guo et al. | Oxidation behaviour and strength degradation of a Yb2O3− SiO2− doped hot-pressed silicon nitride between 1200 and 1500° C | |
| US5352643A (en) | High strength alumina and process for producing same | |
| JP2000256066A (en) | Silicon nitride-base sintered compact, its production and wear resistant member using same | |
| JP4546609B2 (en) | Ceramic heat treatment material with excellent thermal shock resistance | |
| KR900005513B1 (en) | Carbon containing refractories | |
| Dutta et al. | Characterization and properties of controlled nucleation thermochemical deposition (CNTD)-silicon carbide | |
| JP3480499B2 (en) | Method for producing high-density polycrystalline silicon carbide molded article | |
| JP2005298304A (en) | Highly dense silicon carbide ceramic and its producing method | |
| Travitzky | Mechanical properties and microstructure of mullite whisker-reinforced magnesium aluminosilicate glass with cordierite composition | |
| JPH09328364A (en) | Material for molten metal use | |
| JP2974534B2 (en) | Refractory manufacturing method and refractory | |
| Penkov et al. | A new glass ceramic material with high resistance to molten aluminium | |
| JP5002087B2 (en) | CHROMIA SINTERED BODY AND ITS MANUFACTURING METHOD |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term | ||
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080422 Year of fee payment: 16 |