JPS61202806A - Muddy casting molding method - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は泥漿の鋳込み成形方法に関するものである。[Detailed description of the invention] [Industrial application field] This invention relates to a slurry casting method.

泥漿鋳込み成形方法は、古くから陶磁器、衛生陶器等の
成形方法としてよく知られておシ、通常、優れた吸水性
を有する石膏型に泥漿を流し込み成形する方法である。The slurry casting method has been well known for a long time as a method for molding ceramics, sanitary ware, etc., and is usually a method in which slurry is poured into a plaster mold that has excellent water absorbency.

この泥漿鋳込み成形方法は、設備、工程が簡単で複雑形
状に成形出来る成形方法として知られている。This slurry casting method is known as a molding method that requires simple equipment and processes and can be molded into complex shapes.

ところで近年アルミナ（Ａｔ、Ｏ，）　、炭化珪素（８
１Ｃ）　、窒化珪素（５ｉ３Ｎ４）、ジルコニア（Ｚｒ
Ｏ２）等のファインセラミックスにも応用されつつあシ
、工業用部品の成形が試みられている。By the way, in recent years alumina (At, O,) and silicon carbide (8
1C), silicon nitride (5i3N4), zirconia (Zr
It is being applied to fine ceramics such as O2), and attempts are being made to mold industrial parts.

また用いる型は従来石膏型が一般的であったが、近年石
膏型以外の通気性型も開発されている。Furthermore, although plaster molds have conventionally been commonly used, breathable molds other than plaster molds have also been developed in recent years.

〔従来の技術〕[Conventional technology]

泥漿鋳込み成形には、余剰の泥漿を排出する工程を有し
、均一な厚みを有する排泥鋳込み成形方法と、泥漿を排
出する工程が無く、厚みが均一・不均一のいずれも成形
出来る固形鋳込み成形方法がある。Slurry casting involves a step of draining excess slurry, resulting in a uniform thickness, and a solid casting method, which does not include a step of draining the slurry and allows molding with either uniform or non-uniform thickness. There is a molding method.

その工程は、例えば陶磁器を成形する場合、陶土の泥漿
に水ガラス（ケイ酸ナトリウム）を解膠剤として添加し
、泥漿の分散性を高め、石膏型に鋳込む。型が吸水する
につれ、型面に沿って泥漿中の粉末が着肉し、所望の形
状に成形される。成形完了後も成形体内から型へ水分移
動が続き、ある程度成形体の水分が減少すると着肉体の
乾燥収縮が起き、型から成形体が離れる（脱型）という
順序で、陶磁器の成形体が得られる。For example, when molding ceramics, water glass (sodium silicate) is added as a deflocculant to the clay slurry to improve the dispersibility of the slurry, and the slurry is cast into a plaster mold. As the mold absorbs water, the powder in the slurry adheres to the mold surface, forming the desired shape. Even after the molding is completed, moisture continues to move from the molded body to the mold, and when the moisture in the molded body decreases to a certain extent, drying shrinkage of the adhered body occurs, and the molded body separates from the mold (demolding), and in this order, a ceramic molded body is obtained. It will be done.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

固形鋳込み成形法で中子に通常の石膏型を用いると、成
形体が脱呈する際、成形体が収縮する為、中子型が外せ
なくなシ、多くの場合、成形体が割れてしまう。When a normal plaster mold is used as a core in the solid casting method, the molded product contracts when it is removed, making it impossible to remove the core mold, and in many cases, the molded product breaks.

〔問題点を解決するための手段〕[Means for solving problems]

この発明の泥漿鋳込み成形方法は、中子に成形中は変形
せず、成形体が脱塑時収縮する際その収縮に負けて同様
に収縮する発泡形状骨格の石膏型を用いて成形すること
である。The slurry casting method of the present invention uses a plaster mold with a foamed skeleton that does not deform during molding and shrinks when the molded product shrinks during deplasticization. be.

また、本発明の泥漿鋳込み成形の原料粉末は、セラミッ
クス、金属等、成形が可能であれば特に限定するもので
はない。また発泡剤も特に限定するものではなく、泥漿
中の原料粉末粒径に応じて適切な発泡率を決めれば良い
。Further, the raw material powder for slurry casting molding of the present invention is not particularly limited as long as it can be molded, such as ceramics and metals. Further, the foaming agent is not particularly limited, and an appropriate foaming rate may be determined depending on the particle size of the raw material powder in the slurry.

更に成形する為の型は石膏型に限らず、通気性を有し、
成形可能であれば何でも良い。Furthermore, the mold for molding is not limited to plaster molds, but has air permeability.
Anything is fine as long as it can be molded.

〔作用〕[Effect]

本発明者らは、発泡形状骨格の石膏型の有効性について
テストを行った。The inventors tested the effectiveness of foam-shaped skeleton plaster molds.

この発泡石膏型は、半水石膏（ＣａＳＯ４−０，５Ｈ２
０）に発泡料として例えば炭化カルシウム（ＣａＣｚ）
を混合し、蒸留水（Ｈ２Ｏ）に溶かし水溶性泥漿として
、型に流して固化させることによシ作製出来る。また発
泡剤の添加量によシ、発泡空間率を変える事が出来る。This foamed plaster mold is made of hemihydrate gypsum (CaSO4-0,5H2
0) as a foaming agent, such as calcium carbide (CaCz).
It can be produced by mixing and dissolving in distilled water (H2O) to form a water-soluble slurry, pouring it into a mold and solidifying it. Furthermore, the foaming porosity can be changed depending on the amount of foaming agent added.

またこの発泡石膏型は水で湿潤状態になると極端にもろ
くなシ、外力に対してかなシ柔軟性を有する様になる。In addition, when this foamed plaster mold becomes wet with water, it becomes extremely brittle and flexible against external forces.

更に１００℃以上で加熱すれば短時間でくずれて、中子
の形状を保たなくなる性質を持っている。Furthermore, if it is heated above 100°C, it will collapse in a short period of time, and the core will no longer maintain its shape.

本発明者らは、円筒１４イブ１（外径１２０、肉厚１０
　ｗｇ、　）を成形する為に第１図の様な型式を決め、
通常の石膏型２と発泡石膏中子３０組み合わせ型とした
。テストに用いた泥漿は、平均粒径約１．０μ、α相率
＃９１％の窒化珪素（Ｓｌ、Ｎ４）粉末９２重量部に焼
結助剤として平均粒径約１．０μのスピネル（ＭｇＡｔ
２０４）を加え、蒸留水３５重量部に溶かし、水溶泥漿
としポリアクリル酸のアンモニウム塩を解膠剤とじて０
、２１１量部添加し、泥漿の粘度を調整して作製した。The inventors have developed a cylinder 14 Eve 1 (outer diameter 120, wall thickness 10
In order to mold wg, ), we decided on a model as shown in Figure 1,
A combination mold of 2 ordinary plaster molds and 30 foamed gypsum cores was used. The slurry used in the test consisted of 92 parts by weight of silicon nitride (Sl, N4) powder with an average particle size of about 1.0 μm and an α phase ratio of #91%, and spinel (MgAt) with an average particle size of about 1.0 μm as a sintering aid.
204), dissolved in 35 parts by weight of distilled water, made into an aqueous slurry, and mixed with ammonium salt of polyacrylic acid as a peptizer.
, 211 parts by weight were added to adjust the viscosity of the slurry.

発泡石膏型は通常の鋳込み成形用の石膏型を作る為の原
料である半水石膏（Ｃａ　ＳＯ４・０．５Ｈ２０）に炭
化カルシウム（ＣａＣｚ　）を添加し、その粉末１００
重量部を蒸留水８０重量部に溶かし、水溶泥漿として型
に流し込み発泡固化させて作製したＯ また比較テスト用として、通常の陶磁器鋳込み成形用の
石膏型中子を用いた。テストに於ける中子の結果を第１
表に記す。Foamed gypsum molds are made by adding calcium carbide (CaCz) to hemihydrate gypsum (CaSO4.0.5H20), which is the raw material for making plaster molds for regular cast molding, and making 100% of the powder.
O was prepared by dissolving part by weight in 80 parts by weight of distilled water, pouring it into a mold as an aqueous slurry, and foaming and solidifying it.Also, as a comparative test, a plaster mold core for ordinary ceramic casting molding was used. The first result of the middle child in the test
Write it down in the table.

この結果よシ発泡石膏型の効果が認められたが、発泡率
が小さすぎると成形体収縮力では中子は収縮せず、結局
成形体は割れてしまう。また発泡率が大きすぎると、発
泡空間径が大きくなる為、泥漿中の粉末が入シ込んでし
まう。The results showed that the foamed gypsum mold was effective, but if the foaming rate was too small, the core would not shrink under the shrinkage force of the molded product, and the molded product would eventually crack. Moreover, if the foaming rate is too large, the foaming space diameter will become large, and powder in the slurry will enter.

従がって泥漿中の粉末の粒径に応じて、発泡率の適切表
範囲を決めればよい。Therefore, an appropriate table range for the foaming rate may be determined depending on the particle size of the powder in the slurry.

以下に実施例、比較例を記す。Examples and comparative examples are described below.

（実施例１） 第２図に示す様な厚みが均一の回転？ットミル４（肉厚
１０、内径１５０．高さ３００ｓｏ＊）の本体部を成形
する為に第３図に示す様な型式用いた泥漿、中子用の発
泡石膏、外盤用の通常の陶磁器石膏は前述のテストと同
様にした。(Example 1) Rotation with uniform thickness as shown in Figure 2? To mold the main body of the mill 4 (wall thickness 10, inner diameter 150, height 300so*), we used the slurry shown in Figure 3, foamed plaster for the core, and ordinary ceramic plaster for the outer panel. was conducted in the same way as the test described above.

中子の結果を第２表に示す。The results for the core are shown in Table 2.

この結果よシ、ＣａＣ２添加量を０．５〜２．　Ｏｗｔ
％加えれば良好である事がわかった。また成形体を１０
０℃乾燥すると発泡石膏は？口？口に破損し、すべて抜
きさることが出来た。Based on this result, the amount of CaC2 added was 0.5 to 2. Owt
% was found to be good. In addition, 10 molded bodies
What about foamed plaster when dried at 0℃? mouth? It was damaged in the mouth and I was able to pull it all out.

（比較例１） 実施例と同様な型式で、泥漿も同様とし、中子に通常の
陶磁器鋳込み成形用の石膏型を用いた。中子の結果を第
３表に記す。(Comparative Example 1) The mold was the same as in the example, the slurry was also the same, and a plaster mold for ordinary ceramic casting was used as the core. The results for the core are shown in Table 3.

第３表 〔発明の効果〕 この発明の泥漿鋳込み方法は、上記のようなもので、中
子に発泡形状骨格の石膏型を用いて成形することによシ
、割れのない成形体を得ることができる。Table 3 [Effects of the Invention] The slurry casting method of the present invention is as described above, and by molding using a plaster mold with a foamed skeleton as a core, a crack-free molded product can be obtained. I can do it.

【図面の簡単な説明】[Brief explanation of drawings]

第１図はテスト用中子と石膏型との組合せ型の縦断面図
、第２図は実施例の成形体の縦断面図、第３図は第２図
の成形体用の組合せ型の縦断面図である。Fig. 1 is a longitudinal cross-sectional view of a combination mold of a test core and a plaster mold, Fig. 2 is a longitudinal cross-section of a molded body of an example, and Fig. 3 is a longitudinal cross-section of a combined mold for the molded body of Fig. 2. It is a front view.

Claims (1)

【特許請求の範囲】[Claims] 中子として発泡形状骨格の石膏型を用いて成形すること
を特徴とする泥漿鋳込み成形方法。A slurry casting molding method characterized by molding using a plaster mold with a foamed skeleton as a core.