JPH01130844A - Manufacture of core for high pressure casting - Google Patents
Manufacture of core for high pressure castingInfo
- Publication number
- JPH01130844A JPH01130844A JP28976787A JP28976787A JPH01130844A JP H01130844 A JPH01130844 A JP H01130844A JP 28976787 A JP28976787 A JP 28976787A JP 28976787 A JP28976787 A JP 28976787A JP H01130844 A JPH01130844 A JP H01130844A
- Authority
- JP
- Japan
- Prior art keywords
- core
- cavity
- mica
- pressure casting
- sand
- 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
- 238000005266 casting Methods 0.000 title claims abstract description 18
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 8
- 239000004576 sand Substances 0.000 claims abstract description 26
- 239000010445 mica Substances 0.000 claims abstract description 18
- 229910052618 mica group Inorganic materials 0.000 claims abstract description 18
- 239000011247 coating layer Substances 0.000 claims abstract description 16
- 239000000463 material Substances 0.000 claims abstract description 13
- 239000011248 coating agent Substances 0.000 claims description 24
- 238000000576 coating method Methods 0.000 claims description 16
- 239000000126 substance Substances 0.000 claims description 10
- 238000010438 heat treatment Methods 0.000 claims description 6
- 238000000034 method Methods 0.000 abstract description 16
- 238000000465 moulding Methods 0.000 abstract description 8
- 239000012530 fluid Substances 0.000 abstract description 4
- 239000003795 chemical substances by application Substances 0.000 abstract description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 27
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 7
- RJDOZRNNYVAULJ-UHFFFAOYSA-L [O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[F-].[F-].[Mg++].[Mg++].[Mg++].[Al+3].[Si+4].[Si+4].[Si+4].[K+] Chemical compound [O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[F-].[F-].[Mg++].[Mg++].[Mg++].[Al+3].[Si+4].[Si+4].[Si+4].[K+] RJDOZRNNYVAULJ-UHFFFAOYSA-L 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 235000019353 potassium silicate Nutrition 0.000 description 4
- 229910000519 Ferrosilicon Inorganic materials 0.000 description 3
- 239000004115 Sodium Silicate Substances 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 235000019795 sodium metasilicate Nutrition 0.000 description 3
- 229910052911 sodium silicate Inorganic materials 0.000 description 3
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 239000001768 carboxy methyl cellulose Substances 0.000 description 2
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 2
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000012466 permeate Substances 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000002518 antifoaming agent Substances 0.000 description 1
- 229910052626 biotite Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004512 die casting Methods 0.000 description 1
- YGANSGVIUGARFR-UHFFFAOYSA-N dipotassium dioxosilane oxo(oxoalumanyloxy)alumane oxygen(2-) Chemical compound [O--].[K+].[K+].O=[Si]=O.O=[Al]O[Al]=O YGANSGVIUGARFR-UHFFFAOYSA-N 0.000 description 1
- JMGZBMRVDHKMKB-UHFFFAOYSA-L disodium;2-sulfobutanedioate Chemical compound [Na+].[Na+].OS(=O)(=O)C(C([O-])=O)CC([O-])=O JMGZBMRVDHKMKB-UHFFFAOYSA-L 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 230000009969 flowable effect Effects 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 229910052627 muscovite Inorganic materials 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000010422 painting Methods 0.000 description 1
- 229910052628 phlogopite Inorganic materials 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 229920002379 silicone rubber Polymers 0.000 description 1
- 239000004945 silicone rubber Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
Abstract
Description
【発明の詳細な説明】
（発明の目的〕
（産業上の利用分野）
この発明は、ダイカスト法などの高圧鋳造用中子の製造
方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Objective of the Invention) (Industrial Application Field) The present invention relates to a method for producing a core for high pressure casting such as a die casting method.
〈従来の技術）
模型のキャビティに充填した充填砂に高周波を照射し、
充填砂を加熱硬化させて造型する方法は、たとえば特開
昭５７−１５６８６０号公報、特開昭６１−７１１５２
号公報等で知られている。(Conventional technology) High frequency waves are irradiated to the sand filled in the cavity of the model.
Methods of molding by heating and hardening the filled sand are disclosed, for example, in JP-A-57-156860 and JP-A-61-71152.
It is known from the publication No.
これらの造型方法は、模型のキャビティ内面に水ガラス
などの液状塗型剤を霧状に吹付けて塗膜を形成し、つぎ
に塗膜を形成したキャビティ内に流動性のある充填砂を
充填する。そして、このキャビティ内の充填砂に高周波
を照射して充填砂を加熱硬化させて中子を造型する方法
である。These molding methods involve spraying a liquid coating agent such as water glass in a mist onto the inner surface of the model cavity to form a coating film, and then filling the cavity with the coating film with fluid filling sand. do. Then, the filling sand in the cavity is irradiated with high frequency waves to heat and harden the filling sand, thereby molding the core.
この方法によれば、充填砂に流動砂を使用し、しかも塗
型剤に無ｖ１質のベインダを使用しているため、鋳肌の
平滑な鋳物が製造されるが、高圧鋳造用として開発され
たものではない。したがって、前記方法で得られた中子
を高圧鋳造に用いた場合、１００Ｋｙ／ｄ程度の加圧力
で塗型剤層へ溶湯が浸透してしまうという問題がある。According to this method, since fluidized sand is used as the filling sand and V1-free binder is used as the coating agent, castings with smooth casting surfaces are manufactured, but it was not developed for high-pressure casting. It's not something. Therefore, when the core obtained by the above method is used for high-pressure casting, there is a problem that the molten metal permeates into the mold coating layer under a pressure of about 100 Ky/d.
一方、高圧鋳造用中子の製造方法としては、たとえば特
開昭５６−１３９２５６号公報、特開昭５８−１２８２
４５号公報等が知られている。この方法は、有機バイン
ダを用いて砂中子を造型し、この砂中子表面に粉末状の
耐火物と水溶性熱硬化樹脂とを混合したアルカリ性水溶
液からなるスラリーを塗布し、これを乾燥して第１コー
ティング層を形成し、さらにこの第１コーティング層の
表面に合成雲母を含む溶液を塗布し、これを乾燥して第
２コーティング層を形成した方法である。On the other hand, methods for manufacturing cores for high-pressure casting are disclosed, for example, in Japanese Patent Application Laid-open No. 56-139256 and Japanese Patent Application Laid-Open No. 58-1282.
Publication No. 45 and the like are known. This method involves molding a sand core using an organic binder, applying a slurry consisting of an alkaline aqueous solution containing a powdered refractory and a water-soluble thermosetting resin to the surface of the sand core, and drying this. In this method, a first coating layer was formed using the first coating layer, and then a solution containing synthetic mica was applied to the surface of the first coating layer, and this was dried to form a second coating layer.
この方法によれば、耐圧性に優れた中子を造型でき、ま
た表面は合成雲母を含む溶液でコーティングされている
ために、中子の表面にクラックあるいは空孔が形成され
ないが、２回のコーティング作業が必要となる。According to this method, it is possible to mold a core with excellent pressure resistance, and since the surface is coated with a solution containing synthetic mica, no cracks or holes are formed on the surface of the core, but it is possible to mold a core with excellent pressure resistance. Coating work is required.
（発明が解決しようとする問題点）
前述したように、従来の造型方法の前者の方法は、中子
を高圧鋳造に用いた場合に加圧力で塗型剤層へ溶湯が浸
透してしまうという問題がありまたｉ８１の方法は、２
回のコーティング作業が必要となり、作業が繁雑となる
。(Problems to be Solved by the Invention) As mentioned above, in the former method of conventional molding methods, when the core is used for high-pressure casting, the molten metal permeates into the mold coating layer due to the pressurizing force. There is a problem and the i81 method is 2
This requires multiple coating operations, making the work complicated.
この発明は、前記事情に着目してなされたもので、その
目的とするところは、耐圧性に優れた中子を容易に製造
できる高圧鋳造用中子の製造方法を提供することにある
。The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a method for manufacturing a core for high-pressure casting that can easily produce a core with excellent pressure resistance.
（問題点を解決するための手段及び作用）この発明゛は
、模型のキャビティ内面に雲母系物質または鱗片状物質
を含有した水溶性の塗型剤を塗布して塗膜を形成したの
ち、前記キセビティ内に乾式流動自硬性を有する充填砂
を充填し、この充填砂と前記塗膜を高周波加熱によって
硬化させ、基中子の表面に雲母系物質または鱗片状物質
のコーティング層を形成し、コーティング作業を行なう
ことなく雲母系物質または鱗片状物質を含有したコーテ
ィング層が形成されるようにしたことにある。(Means and effects for solving the problems) The present invention is to form a coating film by applying a water-soluble coating agent containing a mica-based substance or a scaly substance to the inner surface of a cavity of a model, and then Filling sand with dry fluid self-hardening properties is filled into the xeviity, and the filling sand and the coating film are hardened by high-frequency heating to form a coating layer of a mica-based substance or a scale-like substance on the surface of the base core, and the coating layer is formed. The purpose is to form a coating layer containing a mica-based substance or a scaly substance without performing any work.
（実施例）
以下、この発明の一実施例を図面にもとづいて説明する
。(Example) Hereinafter, an example of the present invention will be described based on the drawings.
第１図（ａ）〜（ｅ）は高圧鋳造用中子を製造する工程
を示すもので、１は耐熱性に優れたシリコンゴム等の樹
脂材料によって成形された模型であり、２はキャビティ
である。まず、（ａ）に示すようにキャビティ２に塗型
剤３を流し込み、その内面に塗型剤３を一様に付着し、
余分な塗型剤３は（ｂ）に示すように排出する。ここで
使用する塗型剤３は、２００メツシユ以下の天然雲母１
００部に、１％ＣＭＣ（カルボキシメチル・セルロース
）水溶液４０部と水ガラス１部を添加してよく攪拌した
水溶性塗型剤であり、これによって雲母塗膜４が形成さ
れる。つぎに、（Ｃ）に示すように雲母塗膜４が形成さ
れたキャビティ２に充填砂５を充填するが、この充填砂
５は、７号珪砂１００部にＪＩＳ１号水ガラスと５部０
％ＮａＯＨ水溶液でモル比を１．０に調整したメタ珪酸
ソーダ３部を添加する。Figures 1 (a) to (e) show the process of manufacturing a core for high-pressure casting, where 1 is a model molded from a resin material such as silicone rubber with excellent heat resistance, and 2 is a cavity. be. First, as shown in (a), the mold coating agent 3 is poured into the cavity 2, and the mold coating agent 3 is uniformly adhered to the inner surface of the cavity 2.
Excess mold coating agent 3 is discharged as shown in (b). The coating agent 3 used here is natural mica 1 with a mesh size of 200 or less.
A water-soluble coating agent is obtained by adding 40 parts of a 1% CMC (carboxymethyl cellulose) aqueous solution and 1 part of water glass to 0.00 parts and thoroughly stirring the mixture, thereby forming a mica coating film 4. Next, as shown in (C), the cavity 2 in which the mica coating film 4 has been formed is filled with filling sand 5, which consists of 100 parts of No. 7 silica sand, 5 parts of JIS No. 1 water glass, and 0.0 parts of JIS No. 1 water glass.
% NaOH aqueous solution to a molar ratio of 1.0, 3 parts of sodium metasilicate are added.
これをミキサーで混合すると、メタ珪酸ソータが結晶化
し、乾式流動化した時点で硬化促進剤としてフェロシリ
コン粉末１部を添加して充填砂５とする。この乾式自硬
性の充填砂５を雲母塗１１１４が形成されたキャビティ
２にバイブレータをかけながら密に充填したのち、（ｄ
）に示すように高周波加熱炉６の内部に模型１を収納す
る。そして、２部ｗの高周波を１分間照射すると、（ｅ
）に示すように充填砂５および雲ｔｌ’ｌ 塗Ｉｔψ４
は硬化されて基中子７が造型される。造型後、模′型１
から基中子７を取出す。この基中子７の表面には前記キ
ャビティ２の内面に形成した雲母塗膜４、つまり雲母系
物質コーティング層８が形成され、第２図に拡大して示
すように、雲母系物質コーティング層８に充填砂５・・
・が食込んだ状態となって一体化される。When this is mixed with a mixer, the metasilicate sorter crystallizes, and when dry fluidized, 1 part of ferrosilicon powder is added as a hardening accelerator to form the filling sand 5. After densely filling the dry self-hardening filling sand 5 into the cavity 2 in which the mica coating 1114 was formed while applying a vibrator, (d
), the model 1 is housed inside the high-frequency heating furnace 6. Then, when irradiating 2 parts w of high frequency for 1 minute, (e
) As shown in Fig. 5, filler sand 5 and cloud tl'l coating
is hardened to form the base core 7. After molding, model 1
Take out base core 7 from. A mica coating film 4 formed on the inner surface of the cavity 2, that is, a mica-based material coating layer 8 is formed on the surface of this base core 7, and as shown in an enlarged view in FIG. Filled with sand 5...
・is in a state of being wedged in and integrated.
湿式流動砂では、その硬化を速くするために強力な高周
波を用いると水の沸騰現象がみられるが、乾式流動自硬
性の充填砂５は沸騰現象が発生することはなく、また、
従来の約１／２時間で硬化させることができる。In wet fluidized sand, water boiling occurs when a strong high frequency is used to speed up its hardening, but with dry fluidized self-hardening packed sand 5, no boiling phenomenon occurs.
It can be cured in about 1/2 the conventional time.
なお、前記一実施例においては、メタ珪酸ソーダにフェ
ロシリコン粉末を添加して乾式流動自硬性の充填砂５を
形成しているが、フェロシリコン粉末を添加しないメタ
珪酸ソーダのみでも高周波加熱によって硬化できる。In the above embodiment, ferrosilicon powder is added to sodium metasilicate to form the dry-fluid self-hardening filling sand 5, but even sodium metasilicate alone without ferrosilicon powder can be hardened by high-frequency heating. can.
以上の方法で製造された高圧鋳造用中子を金型にセット
し、加圧力５００に９／ｃｄ、ｍ口速度０．９ｍ／５ｅ
Ｃ１溶Ａｍ度７００” Ｃの条件下で加圧ｍ Ｎした。The high-pressure casting core manufactured by the above method was set in a mold, the pressing force was 500, 9/cd, and the opening speed was 0.9 m/5e.
A pressure of mN was applied under conditions of C1 dissolved Am degree of 700"C.
この結果、中子折れは皆無で、中子の表面が雲母コーテ
ィング層によって平滑であるため中子砂は摂動のみで１
００％落ちた。As a result, there was no core breakage, and since the surface of the core was smooth due to the mica coating layer, the core sand could be broken down by only perturbation.
It fell 00%.
なお、前記一実施例における雲母物質は、白雲母、金雲
母、黒雲母、合成雲母等を用いているが、雲母物質に限
定されず、つぎに示す鱗片状物質（金属薄片）を含有す
る塗型剤でもよく、次の組成でもよい。The mica material used in the above embodiment includes muscovite, phlogopite, biotite, synthetic mica, etc., but is not limited to mica materials, and coatings containing the following scaly materials (metal flakes) may also be used. It may be a molding agent or may have the following composition.
鱗片状黒鉛 ３０部ステンレス鋼
扮 １０部合成雲母 、
１５部スルホコハク酸ナトリウム ０．
２部水
５０部消泡剤 数
滴〔発明の効果〕
以上説明したように、この発明によれば、模型のキャビ
ティ内面に雲母系物質または鱗片状物質を含有した水溶
性の塗型剤を塗布して塗膜を形成したのら、キャビティ
内に乾式流動自硬性の充填砂を充填し、この充填砂と前
記塗膜を高周波加熱して硬化させコーティング層を形成
することによって、従来のようにコーティング作業を行
なうことなく、高圧鋳造に耐えられる中子を製造できる
。30 parts of scaly graphite, 10 parts of stainless steel, and 10 parts of synthetic mica.
15 parts Sodium sulfosuccinate 0.
2 parts water
50 parts Antifoaming agent Several drops [Effect of the invention] As explained above, according to the present invention, a water-soluble coating agent containing a mica-based substance or a scale-like substance is applied to the inner surface of the cavity of the model. After forming the film, the cavity is filled with dry-flowing self-hardening filling sand, and the filling sand and the coating film are hardened by high-frequency heating to form a coating layer, and the coating process is carried out as in the conventional method. Cores that can withstand high-pressure casting can be manufactured without the need for casting.
また、鋳造時の加圧力で溶湯が中子の表面に浸透するこ
ともなく、平滑な鋳肌となるという効果がある。さらに
、乾式流動自硬性の充填砂を使用することによって、流
動性に優れ、？！！雑なキャビティであっても充填不良
を招くことがなく、また自硬性を有することから単時間
で硬化し、生産性を向上できるという効果がある。Furthermore, the molten metal does not penetrate into the surface of the core due to the pressure applied during casting, resulting in a smooth casting surface. Furthermore, by using dry flowable self-hardening filling sand, it has excellent fluidity. ! ! Even if the cavity is rough, it will not cause filling defects, and since it has self-hardening properties, it will harden in a single hour, which has the effect of improving productivity.
第１図＜ａ）〜（ｌはこの発明の製造方法の一実施例を
示す説明図、第２図は中子の一部を拡大した断面図であ
る。
１・・・模型、２・・・キヤとティ、３・・・塗型剤、
４・・・塗膜、５・・・充填砂、７・・・基中子、８・
・・コーティング層。Figures 1 <a) to (l are explanatory diagrams showing one embodiment of the manufacturing method of the present invention, and Figure 2 is an enlarged sectional view of a part of the core. 1...Model, 2...・Kiya and Ti, 3...painting agent,
4... Paint film, 5... Filling sand, 7... Base core, 8...
...Coating layer.
Claims (1)
含有した水溶性の塗型剤を塗布して塗膜を形成したのち
、前記キャビティ内に乾式流動自硬性を有する充填砂を
充填し、この充填砂を前記塗膜とともに、高周波加熱し
て硬化させ、基中子の表面に雲母系物質または鱗片状物
質のコーティング層を形成したことを特徴とする高圧鋳
造用中子の製造方法。After applying a water-soluble coating agent containing a mica-based substance or a scaly substance to the inner surface of the model cavity to form a coating film, the cavity is filled with filling sand that has dry flow self-hardening properties. A method for producing a core for high-pressure casting, characterized in that sand is hardened by high-frequency heating together with the coating film to form a coating layer of a mica-based material or a scaly material on the surface of the base core.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28976787A JPH01130844A (en) | 1987-11-17 | 1987-11-17 | Manufacture of core for high pressure casting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28976787A JPH01130844A (en) | 1987-11-17 | 1987-11-17 | Manufacture of core for high pressure casting |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01130844A true JPH01130844A (en) | 1989-05-23 |
Family
ID=17747495
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP28976787A Pending JPH01130844A (en) | 1987-11-17 | 1987-11-17 | Manufacture of core for high pressure casting |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01130844A (en) |
-
1987
- 1987-11-17 JP JP28976787A patent/JPH01130844A/en active Pending
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