JPS6036312A - Production of alpha-type silicon nitride - Google Patents
Production of alpha-type silicon nitrideInfo
- Publication number
- JPS6036312A JPS6036312A JP14376383A JP14376383A JPS6036312A JP S6036312 A JPS6036312 A JP S6036312A JP 14376383 A JP14376383 A JP 14376383A JP 14376383 A JP14376383 A JP 14376383A JP S6036312 A JPS6036312 A JP S6036312A
- Authority
- JP
- Japan
- Prior art keywords
- powder
- resin
- nitrogen
- silicon nitride
- silica
- 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
- 229910052581 Si3N4 Inorganic materials 0.000 title claims abstract description 17
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 title claims abstract description 17
- 238000004519 manufacturing process Methods 0.000 title claims description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 48
- 239000000843 powder Substances 0.000 claims abstract description 37
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 22
- 229920005989 resin Polymers 0.000 claims abstract description 11
- 239000011347 resin Substances 0.000 claims abstract description 11
- 238000006243 chemical reaction Methods 0.000 claims abstract description 7
- 239000000203 mixture Substances 0.000 claims abstract description 6
- 229920001721 polyimide Polymers 0.000 claims abstract description 4
- 239000009719 polyimide resin Substances 0.000 claims abstract description 4
- 239000004640 Melamine resin Substances 0.000 claims abstract description 3
- 229920000877 Melamine resin Polymers 0.000 claims abstract description 3
- 229920001807 Urea-formaldehyde Polymers 0.000 claims abstract description 3
- 229920006122 polyamide resin Polymers 0.000 claims abstract description 3
- 229920005749 polyurethane resin Polymers 0.000 claims abstract description 3
- 239000002994 raw material Substances 0.000 claims description 7
- 230000002829 reductive effect Effects 0.000 claims description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 15
- 239000002245 particle Substances 0.000 abstract description 15
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 7
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 abstract description 6
- 238000005121 nitriding Methods 0.000 abstract description 5
- 229910021529 ammonia Inorganic materials 0.000 abstract description 3
- 239000006232 furnace black Substances 0.000 abstract description 2
- 239000011261 inert gas Substances 0.000 abstract description 2
- 229920003002 synthetic resin Polymers 0.000 description 14
- 239000002952 polymeric resin Substances 0.000 description 13
- 238000000034 method Methods 0.000 description 11
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 10
- 239000000463 material Substances 0.000 description 6
- 239000012298 atmosphere Substances 0.000 description 5
- 239000006229 carbon black Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 229910003481 amorphous carbon Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 125000004433 nitrogen atom Chemical group N* 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 2
- 229910010271 silicon carbide Inorganic materials 0.000 description 2
- 229910002012 Aerosil® Inorganic materials 0.000 description 1
- 241000872198 Serjania polyphylla Species 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000006230 acetylene black Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000006233 lamp black Substances 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920005990 polystyrene resin Polymers 0.000 description 1
- 239000012763 reinforcing filler Substances 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
Landscapes
- Ceramic Products (AREA)
Abstract
Description
【発明の詳細な説明】
本発明はシリカ粉末、カーボン粉末および窒素を含む高
分子樹脂を用いたシリカ還元法による高純度α型窒化け
い素を製造する方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing high purity α-type silicon nitride by a silica reduction method using silica powder, carbon powder, and a nitrogen-containing polymer resin.
α型窒化けい素は耐熱性、高応力性、化学安定性等に優
れていることから高温機械構造材料とし、て開発され２
例えばガスタービンのブレード材やノズル材、その他高
温用ベアリング材等多方面で注目されている。α-type silicon nitride has been developed as a high-temperature mechanical structural material due to its excellent heat resistance, high stress resistance, and chemical stability.
For example, it is attracting attention in many fields such as gas turbine blade materials, nozzle materials, and other high-temperature bearing materials.
このものの製造方法は種々提案されているが１シリカ粉
末とカーボン粉末とを窒素あるいはアンモニア雰囲気に
て加熱する。いわゆるシリカ還元法が採用されている。Various methods have been proposed for producing this product, including heating silica powder and carbon powder in a nitrogen or ammonia atmosphere. A so-called silica reduction method is used.
このα型窒化けい素が各種高温用構造体の焼結原料とＬ
７ての好ましい特徴は高純度であること、微細で粒径が
均一であることのほか低コストで得られることが重要で
ある。この目的を達成せんとし、てシリカ還元法につい
ての改良法が種々開発されている。例えばシリカ粉末、
カーボン粉末の粒径や混合比を調整し、たり、あるいは
前記二原料に第三成分とＬ７てＳ ｉ＋ Ｓ １ｓＮ４
＋ ｓｉｃ。This α-type silicon nitride is used as a sintering raw material for various high-temperature structures.
The preferred characteristics of the above are high purity, fine and uniform particle size, and important that it can be obtained at low cost. In an attempt to achieve this objective, various improved silica reduction methods have been developed. For example, silica powder,
Adjust the particle size and mixing ratio of carbon powder, or add a third component to the two raw materials to add S i+ S 1sN4
+sic.
５ｉｚＯＮ２等を添加混合し、て窒素ガス等の雰囲気の
もとに強熱する方法が開示されている。しかしこれらの
方法はかなりα相含有率は改善されるがまだ不十分であ
り、さらに高純度のα型窒化けい素の出現が要望されて
いる。A method of adding and mixing 5izON2 and the like and igniting the mixture in an atmosphere of nitrogen gas or the like is disclosed. However, although these methods have considerably improved the α phase content, they are still insufficient, and there is a demand for the emergence of even higher purity α-type silicon nitride.
そこで本発明者らはシリカ還元法ζこよるα型窒化けい
素の製造方法を鋭意検討した結果、粉末状のポリイミド
樹脂、メラミン樹脂、ユリア樹脂、ポリアミド樹脂、ポ
リウレタン樹脂力為らなる群より選ばれた一種以上の樹
脂をカーボン粉末と併用してシリカ粉末を還元窒化反応
させることにより高α相含有率でしかも微細で均一な粒
径の窒化けい素粉末を製造できることを見出し本発明を
完成１．た０
以下に本発明の詳細な説明する。Therefore, the inventors of the present invention have intensively investigated the production method of α-type silicon nitride based on the silica reduction method. The present invention was completed by discovering that it is possible to produce silicon nitride powder with a high alpha phase content and a fine and uniform particle size by subjecting silica powder to a reductive nitridation reaction using one or more of the resins obtained in combination with carbon powder.1 ．． The present invention will be described in detail below.
本発明において使用されるシリカ粉末はシＩＪカゲル、
ホワイトカーボンである。使用するシリカ粉末の粒度は
平均粒径で１μｍ以下が好まシ、＜、それ以上の場合は
得られる結晶の粒径力５大きくなるとともに炭化けい素
が生成しやすくなり、α型窒化けい素の含有率が低下す
る傾向にある。The silica powder used in the present invention is Silica gel,
It is white carbon. The particle size of the silica powder used is preferably 1 μm or less in terms of average particle size; if it is larger than that, the particle size of the obtained crystal increases and silicon carbide is more likely to be formed, resulting in the formation of α-type silicon nitride. The content tends to decrease.
本発明で用いられるカーボン粉末とし、てζは無定形の
カーボンブラックが示され、具体的にｌ−ｉファーネス
ブラック、アセチレンブラック、ランプブラック等が挙
げられる。このカーボンブラック粉末の粒度は平均粒径
として１μＹｒＬす、下が好ましい。As the carbon powder used in the present invention, ζ represents amorphous carbon black, and specific examples thereof include li furnace black, acetylene black, lamp black, and the like. The particle size of this carbon black powder is preferably less than 1 μYrL as an average particle size.
分子内に窒素原子を有する各種樹脂の粉末で。Powders of various resins that have nitrogen atoms in their molecules.
具体的にはポリイミド樹脂、メラミン樹脂、ユリア樹脂
、ポリアミド樹脂、ポリウレタン樹脂の粉末に限られる
。これらのうち１種または２種以上を適宜選択して使用
される。樹脂粉末の平均粒径は数μｍ〜数十μｍが適当
である。なお本発明において上記高分子樹脂粉末とし、
て市販の合成樹脂を利用する場合、製品の補強用充填材
とし、てバルブ粉が数十係混入されているものでも使用
上何ら差し支えない。Specifically, it is limited to powders of polyimide resin, melamine resin, urea resin, polyamide resin, and polyurethane resin. One or more of these may be appropriately selected and used. The average particle size of the resin powder is suitably from several μm to several tens of μm. In addition, in the present invention, the above-mentioned polymer resin powder,
When using a commercially available synthetic resin, it may be used as a reinforcing filler for the product, even if it is mixed with dozens of bulb powders.
さらに１本発明で使用する上記窒素を含む高分子樹脂粉
末とともに２分子内に窒素原子を含まない樹脂２例えば
ポリスチレン樹脂、エポキシ樹脂、フェノール樹脂等を
還元剤として併用することは差し支えない。Furthermore, it is possible to use, together with the nitrogen-containing polymer resin powder used in the present invention, a resin 2 which does not contain nitrogen atoms in its molecules, such as polystyrene resin, epoxy resin, phenol resin, etc., as a reducing agent.
本発明方法において何故窒素を含む高分子樹脂粉末が最
適であるかの理由は不詳であるが。The reason why nitrogen-containing polymer resin powder is optimal in the method of the present invention is unknown.
おそらく樹脂の分解直後に生ずる活性な窒素の方が雰囲
気中の窒素よりも反応性が高いためと推定される。This is probably because the active nitrogen produced immediately after the resin decomposes is more reactive than the nitrogen in the atmosphere.
シリカ粉末、カーボン粉末および窒素を含む高分子樹脂
粉末は慣用の手段により均一に混合される。これら原料
の混合比率はシリカ粉末と配合されるカーボン粉末およ
び窒素を含む高分子樹脂粉末の合量がシリカ粉末を還元
できる量以上配合されていれば足りる。従ってシリカ粉
末１００重量部に対し、カーボン粉末２０重量部以上、
窒素を含む高分子樹脂粉末２０重量部以上１合計４０重
量部以上であればよい。さらに好ましくはカーボン粉末
が３０重量部以上。The silica powder, carbon powder, and nitrogen-containing polymer resin powder are uniformly mixed by conventional means. It is sufficient that the mixing ratio of these raw materials is such that the total amount of carbon powder and nitrogen-containing polymer resin powder blended with silica powder is at least an amount that can reduce the silica powder. Therefore, for 100 parts by weight of silica powder, 20 parts by weight or more of carbon powder,
The nitrogen-containing polymer resin powder may be 20 parts by weight or more and 40 parts by weight or more in total. More preferably, the carbon powder is 30 parts by weight or more.
窒素を含む高分子樹脂粉末が３０重量部以上である。合
計４０重量部未満の混合割合では還元材料として不足し
、未反応シリカが残ったり。The amount of polymer resin powder containing nitrogen is 30 parts by weight or more. If the total mixing ratio is less than 40 parts by weight, the reducing material will be insufficient, and unreacted silica may remain.
また不要な８ｉ２ＯＮ２が生成したりして目的を達しな
い。またカーボン粉末が２０重量部未満では高純度のα
型窒化けい素が得られない。窒素を含む高分子樹脂粉末
が２０重量部未満では樹脂添加の効果が低い。カーボン
粉末と窒素を含む高分子樹脂粉末の合計量は経済的面よ
り８００重量部迄で、それ以上ではカーボンが多量に残
存し、還元窒化反応後の酸化工程で多大のエネルギーを
要し好ましくない。In addition, unnecessary 8i2ON2 is generated and the purpose is not achieved. In addition, if the carbon powder is less than 20 parts by weight, high purity α
type silicon nitride cannot be obtained. If the nitrogen-containing polymer resin powder is less than 20 parts by weight, the effect of resin addition is low. The total amount of carbon powder and nitrogen-containing polymer resin powder is limited to 800 parts by weight from an economical point of view; if it exceeds that amount, a large amount of carbon will remain and a large amount of energy will be required in the oxidation process after the reduction-nitridation reaction, which is undesirable. .
シリカ粉末、カーボン粉末および窒素を含む高分子樹脂
粉末からなる混合原料を還元窒化反応させる処理条件は
慣用の方法が採用される。Conventional methods are used for the treatment conditions for reducing and nitriding a mixed raw material consisting of silica powder, carbon powder, and nitrogen-containing polymer resin powder.
ずなわち窒素および／またはアンモニアあるいは窒素−
不活性ガスの雰囲気中で１３５０〜１５５０℃、０５時
間以上混合原料を加熱処理する。温度が１３５０℃未満
では未反応シリカが残り＋ Ｓｉ２０＋’ｈが生成し、
１５５０℃を超えるとβ型窒化けい素や炭化けい素の生
成が著しく、いずれも好ましくない。加熱時間が０５時
間未満だと未反応物が残り好ましくない。i.e. nitrogen and/or ammonia or nitrogen-
The mixed raw materials are heat-treated at 1350 to 1550° C. for 05 hours or more in an inert gas atmosphere. When the temperature is lower than 1350°C, unreacted silica remains and +Si20+'h is generated,
If the temperature exceeds 1550° C., formation of β-type silicon nitride and silicon carbide is significant, and both are unfavorable. If the heating time is less than 0.5 hours, unreacted substances remain, which is not preferable.
以上の還元窒化反応によって得られた窒化けい素含有生
成物にはカーボン粉末および窒素を含む高分子樹脂粉末
の混合比率や還元窒化反応の条件によっては多量のカー
ボンが残存する場合があるが、その場合には慣用の手段
によって酸化処理される。Depending on the mixing ratio of carbon powder and nitrogen-containing polymer resin powder and the conditions of the reductive nitriding reaction, a large amount of carbon may remain in the silicon nitride-containing product obtained by the above reductive nitriding reaction. In some cases, it is oxidized by conventional means.
かくして得られた本発明によるα型窒化けい素は従来の
シリカ還元法による生成物と比べ。The α-type silicon nitride thus obtained according to the present invention is compared with the product obtained by the conventional silica reduction method.
α相含有率の著しく高いものであった。そのため本発明
方法によるα型窒化けい素は顕著な焼結特性を示し、こ
れを原料としたセラミック製品は焼結強度や組織の均一
性により、優れた耐熱性、高応力性、化学的安定性を具
備する高密度の窒化けい素焼結体を製造することが可能
である。The α phase content was extremely high. Therefore, α-type silicon nitride produced by the method of the present invention exhibits remarkable sintering properties, and ceramic products made from this material have excellent heat resistance, high stress resistance, and chemical stability due to the sintering strength and uniformity of the structure. It is possible to produce a high-density silicon nitride sintered body comprising:
次に実施例を示す。Next, examples will be shown.
実施例、比較例
平均粒径７ｍμの日本アエロジル■製ホワイトカーボン
ｌ’−０Ｘ８８０ｊ（商品名）平均粒径４０ｍμの無定
形カーボンブラックおよび平均粒径８０μｍの各種高分
子樹脂を表１〜８に示す種々の比率で混合した。得られ
た混合原料を窒素雰囲気中で１４５０°Ｃ，５時間還元
窒化反応させた後、空気雰囲気下で７５０℃、５時間酸
化処理をした。得られたそれぞれの窒化けい素含有生成
物のα相含有率や不純物を調べ、その結果を表１〜３に
併せ示した。Examples and Comparative Examples White Carbon l'-0X880j (trade name) manufactured by Nippon Aerosil ■ with an average particle size of 7 mμ Amorphous carbon black with an average particle size of 40 μm and various polymer resins with an average particle size of 80 μm are shown in Tables 1 to 8. Mixed in various ratios. The obtained mixed raw material was subjected to a reduction-nitriding reaction at 1450° C. for 5 hours in a nitrogen atmosphere, and then subjected to an oxidation treatment at 750° C. for 5 hours in an air atmosphere. The α-phase content and impurities of each of the obtained silicon nitride-containing products were investigated, and the results are also shown in Tables 1 to 3.
なお、生成物中の組成はＸ線回折による固定試験により
成分量を得た。The composition of the product was determined by a fixation test using X-ray diffraction.
表 １ 表 ３ 特許出願人 日本セメント株式会社 代理人弁理士伊東 彰Table 1 Table 3 Patent applicant: Nippon Cement Co., Ltd. Representative Patent Attorney Akira Ito
Claims (1)
ミン樹脂、ユリア樹脂、ポリアミド樹脂、ポリウレタン
樹脂からなる群より選ばれた一種以上の樹脂の粉末より
なる混合物を還元窒化反応させることを特徴とするα型
窒化けい素の製造法α-type silicon nitride characterized by subjecting a mixture of silica powder, carbon powder, and powder of one or more resins selected from the group consisting of polyimide resin, melamine resin, urea resin, polyamide resin, and polyurethane resin to a reductive nitridation reaction. Raw material manufacturing method
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14376383A JPS6036312A (en) | 1983-08-08 | 1983-08-08 | Production of alpha-type silicon nitride |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14376383A JPS6036312A (en) | 1983-08-08 | 1983-08-08 | Production of alpha-type silicon nitride |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6036312A true JPS6036312A (en) | 1985-02-25 |
Family
ID=15346451
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14376383A Pending JPS6036312A (en) | 1983-08-08 | 1983-08-08 | Production of alpha-type silicon nitride |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6036312A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4701316A (en) * | 1986-08-29 | 1987-10-20 | Allied Corporation | Preparation of silicon nitride powder |
| US4800183A (en) * | 1986-04-09 | 1989-01-24 | The United States Of America As Represented By The United States Department Of Energy | Method for producing refractory nitrides |
| JP2006256939A (en) * | 2005-03-18 | 2006-09-28 | Toda Kogyo Corp | Method for preparing silicon nitride powder |
| JP2008081340A (en) * | 2006-09-26 | 2008-04-10 | Toda Kogyo Corp | Method for manufacturing silicon nitride powder |
| JP2020525393A (en) * | 2017-06-30 | 2020-08-27 | アーエールセー フランスＡｒｃ Ｆｒａｎｃｅ | Method for making glass from a mixture containing calcium oxide, and glass furnace |
-
1983
- 1983-08-08 JP JP14376383A patent/JPS6036312A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4800183A (en) * | 1986-04-09 | 1989-01-24 | The United States Of America As Represented By The United States Department Of Energy | Method for producing refractory nitrides |
| US4701316A (en) * | 1986-08-29 | 1987-10-20 | Allied Corporation | Preparation of silicon nitride powder |
| JP2006256939A (en) * | 2005-03-18 | 2006-09-28 | Toda Kogyo Corp | Method for preparing silicon nitride powder |
| JP2008081340A (en) * | 2006-09-26 | 2008-04-10 | Toda Kogyo Corp | Method for manufacturing silicon nitride powder |
| JP2020525393A (en) * | 2017-06-30 | 2020-08-27 | アーエールセー フランスＡｒｃ Ｆｒａｎｃｅ | Method for making glass from a mixture containing calcium oxide, and glass furnace |
| US11807567B2 (en) | 2017-06-30 | 2023-11-07 | Arc France | Production of glass from a mixture comprising calcium oxide, and glass furnace |
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