JPS62203660A - Production of casting having fine crystal structure - Google Patents
Production of casting having fine crystal structureInfo
- Publication number
- JPS62203660A JPS62203660A JP4611086A JP4611086A JPS62203660A JP S62203660 A JPS62203660 A JP S62203660A JP 4611086 A JP4611086 A JP 4611086A JP 4611086 A JP4611086 A JP 4611086A JP S62203660 A JPS62203660 A JP S62203660A
- Authority
- JP
- Japan
- Prior art keywords
- mold
- auxiliary
- molten metal
- casting mold
- main
- 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 29
- 239000013078 crystal Substances 0.000 title claims description 7
- 238000004519 manufacturing process Methods 0.000 title claims description 4
- 239000002184 metal Substances 0.000 claims abstract description 35
- 238000001816 cooling Methods 0.000 claims abstract description 16
- 210000001787 dendrite Anatomy 0.000 claims abstract description 13
- 238000000465 moulding Methods 0.000 claims abstract description 12
- 238000000034 method Methods 0.000 claims description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 238000007711 solidification Methods 0.000 abstract description 15
- 230000008023 solidification Effects 0.000 abstract description 15
- 238000010438 heat treatment Methods 0.000 abstract description 9
- 239000000498 cooling water Substances 0.000 abstract description 3
- 239000000110 cooling liquid Substances 0.000 description 3
- 239000011800 void material Substances 0.000 description 3
- 239000000956 alloy Substances 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 230000015271 coagulation Effects 0.000 description 2
- 238000005345 coagulation Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 239000002826 coolant Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000005496 eutectics Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 239000012809 cooling fluid Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000005058 metal casting Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
Landscapes
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
- Continuous Casting (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、微細な結晶組織を有する鋳物の製造方法に関
する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a casting having a fine crystal structure.
従来の技術
金属の鋳造品は、急冷凝固させることにより二次デンド
ライト間隔が微細となり、このような微細な二次デンド
ライト間隔により機械的性質が向上することが知られて
いる。そのために、金型に溶湯を圧入後、該金型に冷却
剤を散布して、金型壁を介して浴湯を急冷凝固させる方
法が特開昭５３−５７１２８号公報に提案されている。It is known that the secondary dendrite spacing of conventional metal castings is reduced by rapid cooling and solidification, and that such fine secondary dendrite spacing improves mechanical properties. To this end, JP-A-53-57128 proposes a method in which the molten metal is press-fitted into a mold and then a coolant is sprayed into the mold to rapidly solidify the bath water through the mold wall.
発明が解決しようとする間ｓ！ｑ点
しかしながら、このような従来方法によるときは＃湯の
冷却が金型壁の層を介して行われるものであり、しかも
溶湯の峡固収紬によって金型内面と溶湯の凝固部の間に
空隙が発生し、この空隙が断熱層となって浴湯の熱が金
型壁を介して除去されるのを妨げ、空隙の生じた後の浴
湯の凝固速度が低下し、二次デフドライド間隔が少くと
も５０μｍ以上でろって、好ましく微細化された組織を
有する鋳物を得難い。While invention tries to solve s! Point q However, when such a conventional method is used, the cooling of the molten metal is carried out through the layer of the mold wall, and moreover, the molten metal is trapped between the inner surface of the mold and the solidified part of the molten metal. A void is created, and this void acts as a heat insulating layer that prevents the heat of the bath water from being removed through the mold wall, which reduces the solidification rate of the bath water after the void occurs, and reduces the secondary def-dry interval. is at least 50 μm or more, making it difficult to obtain a casting having a preferably refined structure.
問題点を解決するための平膜
本発明は微細な二次デンドライト間隔の組織を有する鋳
物を得るために、鋳型装置内に圧入された溶湯を急冷凝
固し得る新規な鋳造方法を提供するものであす、所望の
鋳物の形状に対応するキャビティー會有する主鋳型を７
ＪＩ］熱し、該主鋳型と補助的型をよむ詞型摸１ａ内に
溶湯を圧入し、前記補助鋳型内の溶湯が凝固したのち、
該凝固部分を直接に強制冷却して、前記主鋳型内の市街
を指向性凝固させることを特徴とする二次デンドライト
間隔の微細な結晶組ｆ我を有する鋳造の製造方法である
。The present invention provides a novel casting method in which molten metal press-fitted into a molding device can be rapidly solidified in order to obtain a casting having a structure with fine secondary dendrite spacing. Tomorrow, we will create a main mold with a cavity that corresponds to the desired shape of the casting.
JI] Heat and press the molten metal into the mold 1a containing the main mold and the auxiliary mold, and after the molten metal in the auxiliary mold solidifies,
This method of manufacturing a casting having a fine crystal group with secondary dendrite spacing is characterized in that the solidified portion is directly forcedly cooled to cause directional solidification of the inner part of the main mold.
１乍用
加熱された主間型および補助鋳型内に溶湯を圧入し、そ
の補助４＠型内浴湯を後先的に凝固してから該補助鋳型
を除去しその凝固部分を強制的に冷却することにより主
鋳型内溶湯の熱量が補助Ｉｔ） ｚｌで成形された凝固
部の方向に伝導して指向性凝固させる。The molten metal is press-fitted into the heated main mold and auxiliary mold, and the auxiliary bath water in the mold is solidified first, and then the auxiliary mold is removed and the solidified portion is forcibly cooled. By doing so, the amount of heat of the molten metal in the main mold is conducted in the direction of the solidified part formed by auxiliary It) zl, resulting in directional solidification.
この工うな指向性凝固に工って凝固した金属イ１１城に
おける二次デンドライト間隙が微細化し、即ちこの二次
デンドライト間隙を一般的に５０燗以下、特に３５μｍ
以下となる。By using this technique, the secondary dendrite gap in the solidified metal is made finer by directional solidification, that is, the secondary dendrite gap is generally less than 50 μm, particularly 35 μm.
The following is true.
主間型を加熱して圧入溶（寺を溶融状態に保ち、それに
１って＃１湯の湯：刺り不良を防ぎ鋳造性を良好にし、
又前記した指向性凝固を適切に行わしめることにより収
縮巣が発生し難くなる。Heat the main mold to press-fit (keep the temple in a molten state, and the #1 hot water: prevents puncture defects and improves casting properties.
Furthermore, by properly performing the above-mentioned directional coagulation, shrinkage cavities are less likely to occur.
実施例
上記したような不発明について更に説明すると、不発明
においては、鋳物の二次デンドライト間隔の微細な組織
を必要とする部分を製品形状にほぼ等しく形成し、この
ような形状に対応するキャビティーを有する主鋳型と、
前記微細な組織を必要とする主鋳型部分と連通し℃熱移
動を図り、該主＃型部分を指向性凝固させる冷却部分を
形成するだめの補助ｇ型とを含む金型装置を用いる。Embodiment To further explain the above-mentioned invention, in the invention, the part of the casting that requires a fine structure of secondary dendrite spacing is formed approximately equal to the shape of the product, and a cavity corresponding to such shape is formed. a main mold having a tee;
A mold apparatus is used that includes an auxiliary mold that communicates with the main mold part that requires the fine structure and forms a cooling part for directional solidification of the main mold part to achieve heat transfer by degrees Celsius.
前記主鋳型は、主鋳型内の溶湯が補助鋳型に工って形成
された冷却部分によってのみ冷却され凝固するように予
め加熱される。この主＃型の加熱温度は溶湯の組成お二
び溶湯の圧入時温度によって異なるが、４００℃以上好
ましくは６００℃以上に加熱しておくことが望ましい。The main mold is preheated so that the molten metal in the main mold is cooled and solidified only by the cooling portion formed in the auxiliary mold. The heating temperature of this main mold varies depending on the composition of the molten metal and the temperature of the molten metal at the time of injection, but it is desirable to heat it to 400° C. or higher, preferably 600° C. or higher.
殊に主鋳型の熱容量を少なくするために主間型の壁は薄
いことが適切であって、このように主Ｍ型の温［を高温
に保持しておけば、溶湯の温度は液相線温度あるいは共
晶点＠度は上であれはよく、液相ＩｖｊＩあるいは共晶
点温度工すも５０〜１００℃高めとすることで十分であ
る。加熱された主鋳型を使用するので、流動性が悪く鋳
造性の悪い合金も容易に鋳造することができ、又この主
鋳型内の浴場の凝固が指向的に進行していくので、＠果
が製品内に発生することなく健全な鋳物を得ることがで
きる。In particular, in order to reduce the heat capacity of the main mold, it is appropriate for the walls of the main mold to be thin.If the temperature of the main M mold is maintained at a high temperature in this way, the temperature of the molten metal will drop below the liquidus line. It is sufficient that the temperature or eutectic point is higher, and it is sufficient to set the liquid phase IvjI or eutectic point temperature higher by 50 to 100°C. Since a heated main mold is used, it is possible to easily cast alloys with poor flowability and poor castability, and solidification of the bath in this main mold progresses in a directional manner. It is possible to obtain a sound casting without any occurrence in the product.
前記補助鋳型は圧入された／８陽を素早く凝固させるた
めのもので、常温の金型あるいは鋳型内に冷却液の循張
路を有する等の冷却手段を設けた鋳型を使用することが
できる。The auxiliary mold is for quickly solidifying the press-fitted /8 oxide, and can be a room-temperature mold or a mold equipped with a cooling means such as a cooling fluid circulation path in the mold.
このような主鋳型および補助鋳型を倉む′ＩｕＩ型装置
内に溶湯を圧入すると、補助ｇ型内に圧入した溶湯は凝
固するが、主鋳型内に圧入した溶湯は溶融状態が保たれ
る。即ち上記のように補助鋳型内が凝固した後、該補助
鋳型を取り外し、ｔｊ’Ｊ ｉ′ｉｌ’ａ凝固部分に冷
却液をスプレー散布、望ましくは高圧スプレー等で砲し
、該は面部分を１な接に冷却する。この直接の冷却によ
って主鋳型内の溶湯は、前記凝固部分によって熱を尊わ
れ、該溶湯の凝固は冷却部分より製品部分に急速に進行
し指向性凝固が達成され、しかも鋳物“の一部を直接に
冷却するものであるから、鋳型と鋳物との間に断熱空間
が発生することはなく、更に鋳型の壁を介して冷却する
ものでないから冷却速度も速く、二次デンドライト間隔
の倣、別な組織を有する鋳物を製造することができる。When molten metal is press-fitted into the 'IuI type device that houses such a main mold and auxiliary molds, the molten metal press-fitted into the auxiliary g-type solidifies, but the molten metal press-fitted into the main mold remains molten. That is, after the inside of the auxiliary mold has solidified as described above, the auxiliary mold is removed, and the solidified part is sprayed with cooling liquid, preferably by high-pressure spray, etc., and the surface part is Cool to 1. Due to this direct cooling, the molten metal in the main mold is heated by the solidified part, and the solidification of the molten metal progresses rapidly from the cooling part to the product part, achieving directional solidification, and moreover, Because it cools directly, there is no insulation space between the mold and the casting, and because it does not cool through the walls of the mold, the cooling rate is fast, and it is possible to imitate the secondary dendrite spacing and separate the mold. It is possible to produce a casting having a fine structure.
上述した主鋳型としては、金型に１浪ることなく砂型、
シェル型、ロストフオーム等の鋳型を単独で、あるいは
組会わせて使用することができる。また主鋳型の加熱手
段としては、抵抗、加熱、ガス加熱の他、誘導加熱等の
公知の手段が使用できる。更に補助か１型におけるさ湯
の凝固促進のため補助観、！型に冷却液をスプレーする
ことでもできる。The main mold mentioned above is a sand mold, without any damage to the mold.
Molds such as shell molds and lost foam molds can be used alone or in combination. Further, as a heating means for the main mold, known means such as resistance, heating, gas heating, induction heating, etc. can be used. In addition, the auxiliary view is to promote coagulation of hot water in type 1,! You can also spray the mold with coolant.
次に不発明方法における好ましい一実施例について述べ
るが、これに限ることなく、特に補助ｍ型の位置のとり
方、形状などについてはいろいろに変更して実施してよ
いことは明かである。Next, a preferred embodiment of the non-inventive method will be described, but it is clear that the present invention is not limited to this, and that the method may be modified in various ways, particularly with respect to the positioning, shape, etc. of the auxiliary m-shape.
具体的な実施態様を添付する図１６ｉについて説明する
と、本発明による方法を実施するための手順を示すのが
第１〜第３図であって、主鋳型１には加熱手段２を設け
、又補助′！Ａ型３を連設した間型装置７を形成し、こ
れらの鋳型１．３内に溶融金属４を圧入せしめ補助鋳型
造型部５を補助＃型３内で優先的に形成し、このために
補助調型３には第２図のように冷却液８を圧加する。こ
の第２図の工うに補助ｇ型３内お工びそれに連続した主
鋳小１内の一部が凝固した状態で補助Ｍｆｆ３を取外し
、こうして露出した補助鋳型造型部５部分に＠３図で示
すように引続いて直接水冷を行うことにより主鋳型１お
工びその中の熱量は上記造型部５方向に伝専し、従って
この主鋳型１内においては指向凝固金属による製品造型
部６が得られる。Referring to FIG. 16i to which a specific embodiment is attached, FIGS. 1 to 3 show the procedure for carrying out the method according to the present invention, in which the main mold 1 is provided with heating means 2, and auxiliary'! An inter-mold device 7 in which molds A 3 are arranged in series is formed, molten metal 4 is press-fitted into these molds 1.3, and an auxiliary mold forming part 5 is preferentially formed within the auxiliary mold 3, and for this purpose. A cooling liquid 8 is pressurized to the auxiliary mold 3 as shown in FIG. In the process shown in Fig. 2, remove the auxiliary Mff 3 with the inside of the auxiliary mold 3 solidified and a part of the main casting small 1 that is continuous with it, and place the auxiliary mold molding part 5 exposed in this way as shown in Figure 3. As shown, by subsequently performing direct water cooling, the heat in the main mold 1 is transferred in the direction of the molding section 5, and therefore, within the main mold 1, a product molding section 6 made of oriented solidified metal is obtained. It will be done.
上記したようなＭ型装置７は金型で構成され、主＃型１
の壁厚は一般的にＱ、 ５ ｒｍ以上であって本発明者
が具体的に採用したものは１．ＯＮであった。補助鋳型
３の壁厚は一般的に１１１ＩＩ１１以上でおって、具体
的には１０ｍであった。The M-type device 7 as described above is composed of a mold, and the main mold #1
The wall thickness of Q is generally 5 rm or more, and the one specifically adopted by the inventor is 1. It was ON. The wall thickness of the auxiliary mold 3 was generally 111II11 or more, and specifically 10 m.
然してこのような鋳型Ｔを用い工具体向に実施した、Ａ
ｔ−１２％合金合金の鋳造条件は次の如くである。−
主ｌｊ型１の加熱温度 ６００℃
溶湯の組成および温度 ＡＣａＡ、６５０℃製品部の
肉厚および重量 １０■１１．５Ｋｇ補助鋳型内部分の
重！ ０．５１＜ｊ１即ち前記した第１〜第３図の
ような各過程を経しめ、第３図の過程で凝固金属９部分
にスプレーされた冷却水量は１秒間に０．５ｔであって
、このようにして主鋳型１内の溶湯を指向凝固させた。However, using such a mold T, A
The casting conditions for the t-12% alloy are as follows. - Heating temperature of main lj mold 1 600℃ Composition and temperature of molten metal ACaA, 650℃ Thickness and weight of product part 10 ■ 11.5Kg Weight of inside of auxiliary mold! 0.51<j1 That is, the amount of cooling water sprayed on the solidified metal 9 portion in the process shown in FIG. 3 after going through the steps shown in FIGS. 1 to 3 described above is 0.5 t per second, In this way, the molten metal in the main mold 1 was directionally solidified.
得られた製品（主’１Ｊｆｊｌ！１で造型された部分）
についてそのｍＥ＆を***したところ、二次デンドライ
ト間隔は１０〜２５μｍであって非常に微細な結晶組織
を得ることができ、収縮巣の発生も認められなかった。Obtained product (part molded with main '1Jfjl!1)
When the mE& was counted, the secondary dendrite spacing was 10 to 25 μm, a very fine crystal structure could be obtained, and no shrinkage nests were observed.
これに対し比較のため、上記と同じ主鋳型に対し溶湯性
人後、該開型外面に冷却水をスプレーして冷却する従来
方法に工す得られたものの組織は二次デンドライト間隔
が５０〜１００μｍであす、収都果も発生していた。On the other hand, for comparison, we used the same main mold as above and used the conventional method of spraying cooling water on the outer surface of the open mold after cooling the molten metal. At 100 μm, harvested fruits were also appearing.
即ち本発明方法によるときは非常に微細な結晶組織を有
する鋳物を得ることができ、収縮巣も発生し難いことか
らその機械的性質を適切に向上し得ることが確認された
。In other words, it has been confirmed that the method of the present invention makes it possible to obtain a casting having a very fine crystal structure, and since shrinkage cavities are less likely to occur, its mechanical properties can be appropriately improved.
「発明の効果」
以上説明したような不発明によるときは補助鋳型造型部
分を主鋳型による製品造型部分に連続成型し、この補助
鋳型造型部分を優先的に凝固せしめてから該部分を直接
に強制冷却して主鋳型内の製品造型部分に相当した溶湯
を指向性、凝固させるものであるから二次デンドライト
間隔が微細な結晶組織とされた製品を確実に得ることが
でき、父上記のように指向性凝固させるものでろるから
該製品造型部分の凝固組織に収縮巣などを発生し難くシ
、この点においても優質の製品を得しめるものであって
、工業的にその効果の大きい発明である。"Effects of the Invention" In the case of non-invention as explained above, the auxiliary mold molding part is continuously molded into the product molding part by the main mold, the auxiliary mold molding part is preferentially solidified, and then the said part is directly forced. Since the molten metal corresponding to the product molding part in the main mold is cooled and solidified in a directional manner, it is possible to reliably obtain a product with a crystal structure with fine secondary dendrite spacing, and as mentioned above. Since it is directional solidification, it is difficult to generate shrinkage nests in the solidified structure of the product molding part, and in this respect as well, it is possible to obtain a product of excellent quality, and it is an invention that has great industrial effects. .
図面は不発明の実施態様を示すものであって、第１図は
本発明方法における注湯状態の断面的説明図、第２図は
その補助鋳型部分に対する冷却凝固過程の第１図と四様
な断面的説明図、第３図はその主＠型内製品造型部分に
対する冷却凝固過程の断面的説明図である。
然してこれらの図面において、１は王＠型、２はその加
熱手段、３は補助鋳型、４は浴融金属、５は補助鋳型造
型部、６は指向性凝固による製品造型部分、７は鋳型装
置、８は冷却液を示すものである。The drawings show an embodiment of the invention, in which Fig. 1 is a cross-sectional explanatory diagram of the pouring state in the method of the present invention, and Fig. 2 shows the cooling and solidification process of the auxiliary mold part in the cooling solidification process shown in Fig. 1 and four aspects. FIG. 3 is a cross-sectional explanatory view of the cooling solidification process for the main part of the product forming part in the mold. In these drawings, 1 is the king@mold, 2 is its heating means, 3 is an auxiliary mold, 4 is a bath metal, 5 is an auxiliary mold making section, 6 is a product making section by directional solidification, and 7 is a mold device. , 8 indicates a cooling liquid.
Claims (1)
型を加熱し、この主鋳型と補助鋳型とを含む鋳型装置内
に浴湯を圧入し、前記補助鋳型内の溶湯が凝固してから
該補助鋳型を除去し、該補助鋳型造型部分を直接に強制
冷却し、前記主鋳型内の溶湯を指向性凝固させることを
特徴とする、二次デンドライト間隔の微細な結晶組織を
有する鋳物の製造方法。A main mold having a cavity corresponding to the shape of the desired casting is heated, and bath water is press-fitted into a molding device including the main mold and an auxiliary mold, and after the molten metal in the auxiliary mold has solidified, the auxiliary mold is heated. A method for producing a casting having a fine crystal structure with secondary dendrite spacing, the method comprising: removing the mold, directly forcing cooling of the auxiliary mold molding portion, and directional solidifying the molten metal in the main mold.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4611086A JPS62203660A (en) | 1986-03-05 | 1986-03-05 | Production of casting having fine crystal structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4611086A JPS62203660A (en) | 1986-03-05 | 1986-03-05 | Production of casting having fine crystal structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS62203660A true JPS62203660A (en) | 1987-09-08 |
Family
ID=12737852
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4611086A Pending JPS62203660A (en) | 1986-03-05 | 1986-03-05 | Production of casting having fine crystal structure |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62203660A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105033180A (en) * | 2015-06-26 | 2015-11-11 | 北京北冶功能材料有限公司 | Fired mold precision casting method for improving solidification heat dissipation conditions of directional solidification casting |
-
1986
- 1986-03-05 JP JP4611086A patent/JPS62203660A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105033180A (en) * | 2015-06-26 | 2015-11-11 | 北京北冶功能材料有限公司 | Fired mold precision casting method for improving solidification heat dissipation conditions of directional solidification casting |
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