JP2004243330A - Salt core for light alloy casting, its manufacturing method, and method for manufacturing light alloy cast product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a salt core for light alloy casting, a salt core that can be easily removed from a cast product after light alloy casting and that can eliminate post processing including shot blast, sand blast, and spray of high pressure water, and also to provide its manufacturing method and method for manufacturing light alloy cast product using this salt core. <P>SOLUTION: This melting salt core is used for casting of a light alloy cast product such as the cast product of an aluminum alloy or magnesium alloy, and is manufactured by using nitrate in which the fusion point of the melting salt is in the range higher than 290°C and not higher than 500°C. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００１２】
以上の結果から、軽合金鋳物の鋳造用中子に用いる塩の融点はある程度高いものが必要であることが判る。
【００１３】
次に上記の硝酸塩中子を用いて鋳造したアルミ合金鋳物を同一成分の塩浴中に（各塩の融点より５０〜７０℃程度高い温度）漬け、塩中子を溶解後、６０〜８０℃の温水に漬けて洗浄した。その洗浄水は硝酸塩濃縮装置（新東ブレ−タ製「排水濃縮装置 型式００４０」）にて硝酸塩濃度を高め、その高めた塩水を塩浴（溶融状態）に戻し、硝酸塩がシステム外に出ないクローズドシステムとした。また鋳造後、直ちに温水もしくは水蒸気にて洗浄してもよいが、上記装置の能力がかなり大きいものが必要になるため、鋳造後は塩浴中にて塩中子を溶解するほうが望ましい。
【００１４】
【発明の効果】
本発明は、上記の説明から明らかなように、アルミ合金鋳物又はマグネシウム合金鋳物等の軽合金鋳物の鋳造に用いる溶融塩中子であって、該溶融塩の融点が２９０℃より高く５００℃以下の範囲内の硝酸塩を使用したことを特徴とする軽合金鋳物鋳造用塩中子及びこの軽合金鋳物鋳造用塩中子の製造方法並びにその塩中子を使用する軽合金鋳物の製造方法であるから、砂落し等の必要がなく、装置、処理が容易になり、また塩をシステム外に出さないようにすることにより、環境に対しても配慮したシステムとなる等優れた効果がある。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a salt core suitable for casting a light alloy casting (aluminum alloy casting or magnesium alloy casting), a method of manufacturing the salt core, and a method of manufacturing a light alloy casting cast using the salt core.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a casting method of a light alloy casting such as an aluminum alloy casting or a magnesium alloy casting, there are a gravity casting, a low pressure casting, a high pressure die casting, a squeeze die casting and the like using a sand mold and a mold. However, when a core is used in any casting process, a sand core is used (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-03-23035 (pages 1-3, FIG. 1)
[0004]
[Problems to be solved by the invention]
As described above, sand cores are used in casting of light alloy castings such as aluminum alloy castings and magnesium alloy castings. However, it was not possible to completely remove the sand, and a CCD scope or the like was used to inspect for remaining sand and to remove the sand by hand.
[0005]
The present invention has been made in order to solve the above problems, and after casting a light alloy casting, the core can be easily removed from the casting, and shot blasting, sand blasting, and post-processing such as spraying with high-pressure water. It is an object of the present invention to provide a salt core for casting a light alloy casting which can be omitted, a method for manufacturing the same, and a method for manufacturing a light alloy casting.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a salt core for casting a light alloy casting in the present invention is a molten salt core used for casting a light alloy casting such as an aluminum alloy casting or a magnesium alloy casting, wherein the molten salt is A nitrate having a melting point of higher than 290 ° C. and not higher than 500 ° C. is used. It is characterized by containing either strontium. Here, in the present invention, the melting point refers to a solidus temperature.
[0007]
Further, in the method for producing a salt core for casting a light alloy casting according to the present invention, a molten salt state of nitrate having a melting point in a range of higher than 290 ° C. and not higher than 500 ° C. is poured into a mold and solidified and solidified. It is characterized in that it is released from the mold. In addition, in the production of light alloy castings, warm water or steam whose salt has been washed using a hot water bath or steam, the salt concentration is increased by a nitrate concentration method, the high-concentration salt water is returned to the salt bath, and further poured into a mold. After solidification and solidification, the mold is released from the mold.
[0008]
Further, the method for producing a light alloy casting according to the present invention comprises casting a light alloy casting using a molten salt core having a melting point in the range of higher than 290 ° C and not higher than 500 ° C, and using a hot water bath or steam for the salt core. To produce a light alloy casting. In addition, a light alloy casting is cast using a molten salt core having a melting point higher than 290 ° C. and not higher than 500 ° C., and the light alloy casting is immersed in a salt bath for melting the salt core and melted. Then, after taking out, the salt adhering to the casting is removed using a hot water bath or steam to produce a light alloy casting.
[0009]
Here, the reason why the melting point of the molten salt is set to be higher than 290 ° C. and lower than 500 ° C. is as follows. When the melting point is 290 ° C. or lower, there is no problem in the case where the thickness of the light alloy casting is thin, but when the thickness of the light alloy casting is thick or the temperature of the mold is high in the case of casting using a mold, the salt core is used. Is dissolved. If the melting point is higher than 500 ° C., it is difficult to remove the salt core using a hot water bath or steam.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
(Example)
First, as a basic test, the cast aluminum material was AC4B, and under quite severe conditions of a mold temperature of 400 ° C. and a pouring temperature of 740 ° C., nitrate (sodium nitrate, barium nitrate, potassium nitrate, sodium nitrite) was used as a salt core material. A mixed salt having a melting point of 300 ° C., 380 ° C., 455 ° C., 495 ° C., and 510 ° C. is heated to a liquid state, then poured into a mold and solidified to form a salt core. , A casting test was performed. Table 1 shows the results.
[0011]
[Table 1]

[0012]
From the above results, it is understood that the salt used for the casting core of the light alloy casting needs to have a certain high melting point.
[0013]
Next, the aluminum alloy casting cast using the above-mentioned nitrate core is immersed in a salt bath of the same component (at a temperature about 50 to 70 ° C. higher than the melting point of each salt), and after dissolving the salt core, the temperature is 60 to 80 ° C. Washed in hot water. The washing water is increased in nitrate concentration by a nitrate concentrator (“Drainage Concentrator Model 0040” manufactured by Shinto Breta), and the increased salt water is returned to a salt bath (in a molten state) so that nitrate does not go out of the system. Closed system. After casting, it may be washed with hot water or steam immediately. However, since the above-mentioned apparatus requires a considerably large capacity, it is preferable to dissolve the salt core in a salt bath after casting.
[0014]
【The invention's effect】
The present invention is, as apparent from the above description, a molten salt core used for casting a light alloy casting such as an aluminum alloy casting or a magnesium alloy casting, wherein the melting point of the molten salt is higher than 290 ° C and 500 ° C or less. A salt core for casting a light alloy casting, a method of manufacturing the salt core for casting a light alloy casting, and a method of manufacturing a light alloy casting using the salt core, characterized by using a nitrate in the range of Therefore, there is no need to remove sand and the like, and the apparatus and treatment are easy, and by preventing salt from leaving the system, there are excellent effects such as a system that is environmentally friendly.

Claims (6)

A molten salt core used for casting an aluminum alloy casting or a magnesium alloy casting or other light alloy casting, wherein the molten salt is a nitrate having a melting point higher than 290 ° C and lower than 500 ° C. Salt core for casting light alloy castings. The light nitrate casting according to claim 1, wherein the nitrate contains at least one of barium nitrate and strontium nitrate as a component among sodium nitrate, potassium nitrate, sodium nitrite, barium nitrate, and strontium nitrate. Salt core. A salt core for light alloy casting casting, wherein a molten salt state of nitrate having a melting point higher than 290 ° C. and not higher than 500 ° C. is poured into a mold, and after solidification and solidification, is released from the mold. Manufacturing method. Casting a light alloy casting using a molten salt core having a melting point higher than 290 ° C and not higher than 500 ° C, and removing the salt core using a hot water bath or steam to produce a light alloy casting. Characteristic light alloy casting manufacturing method. A light alloy casting is cast using a molten salt core having a melting point higher than 290 ° C and not higher than 500 ° C, and the light alloy casting is immersed and dissolved in a salt bath for melting the salt core, A method for producing a light alloy casting, comprising removing a salt adhering to the casting using a hot water bath or steam after taking out the light alloy casting to produce a light alloy casting. The method for producing a light alloy casting according to claim 4 or 5, wherein the salt concentration of hot water or steam whose salt has been washed using a hot water bath or steam is increased by a nitrate concentration method, and the high-concentration salt water is returned to the salt bath. A method for producing a salt core for light alloy casting casting, further comprising: pouring the mixture into a mold; solidifying and solidifying the mixture; and releasing the mold from the mold.