JP2003126955A - Molding method and molding die for semisolid metal goods - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of molding semisolid metal by pressurization without taking complicated steps and provide a die used in the method. SOLUTION: A die to be used is provided with a lower die having a concave part which is large enough to accommodate semisolid metal and a upper die, and semisolid metal is filled in a space formed by them and moreover, if necessary, by a slide core and a casting product is molded. Semisolid metal having minute spherical crystal with a solid phase rate ranging from 30% to 99.9% is accommodated in the concave part of the lower type die and is filled in a space for a product formed by the transfer of the upper die, the lower die and, if necessary, the slide core.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming semi-solidified metal, and in particular, placing the semi-solidified metal on a mold and directly applying a pressure by an upper mold or a pressure pin to produce a high-quality molded product. The present invention relates to a method for forming a semi-solid metal to be formed.

[0002]

2. Description of the Related Art In semi-solidifying molding, generally, a semi-solidifying metal produced by heating a semi-solidifying metal or a solid material by lowering the temperature from a liquid into a mold is temporarily put into a sleeve. Then, the tip in the sleeve is moved and then molded.

[0003]

However, the above method has some problems. First, when the metal in the solid-liquid coexistence state comes into contact with the sleeve at the stage of being inserted into the sleeve to rapidly remove heat, a solidified layer is likely to be formed. For this reason, the solidified layer easily mixes with the movement of the chip, and when the metal is inserted into the mold for molding, variations in mechanical properties are likely to occur. Second, the ratio of the biscuit portion left in the sleeve and the portion other than the product including the runner up to the product to the total cast weight is high. Especially in the case of small products, the ratio becomes high. As a result, the product price increases.

For this reason, it is known to directly insert a semi-solidified metal into a mold for molding. However, the semi-solid metal that contacts the lower mold is likely to form a solidified layer as well.
In particular, when the container is turned over and the semi-solidified metal held therein is placed in the lower mold for molding, an oxide is mixed in the bottom.

Also, many products have a cast-out portion and a window portion into which the cast metal does not enter, but as the mold is closed, the semi-solid metal is completely removed from the cast-out portion and the window portion. It is difficult to do so when the metal is already placed on the lower mold.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a metal mold used in the same method as the method of pressure-forming a semi-solid metal without taking a complicated method. Is.

[0007]

In order to solve such problems, in the present invention, in the first invention, a semi-solid metal having fine spherical crystals with a solid fraction of 30% to 99.9% is used. The semi-solid metal was placed in the recess of the lower mold, and the product space formed by moving the upper mold, the lower mold and, if necessary, the slide core was filled with the semi-solid metal.

In the second invention, which is mainly based on the first invention, the semi-solid metal is compressed as the upper die approaches the lower die, and the semi-solid metal is filled in the die. The interval between the upper die convex portion having a cavity forming portion provided in the upper die and the lower die is set to 0.5 mm to 10 mm, and the portion corresponding to the cavity is cut and penetrated by cutting after casting. I decided.

In the third invention, which is mainly based on the first invention,
When closing the upper and lower molds and then compressing the semi-solidified metal filled in the mold with a pressure pin, the upper mold convex portion having a cavity forming portion provided in the upper mold and the lower mold The interval was set to 0.5 mm to 10 mm, and after casting, the portion corresponding to the cavity was cut and cut to penetrate.

According to a fourth aspect of the invention, which is mainly based on the first or second aspect of the invention, the lower mold cavity portion of the semi-solidified metal filled in the product space formed by the upper and lower dies is locally pressurized by a pressure pin. , it was decided to separate and remove the parts from the product as necessary.

According to a fifth aspect of the invention, which is mainly based on the first, second or fourth aspect, the lower die contact portion of the lower die recess of the semi-solid metal filled in the product space formed by the upper and lower dies is cut. It was decided to process and remove it.

According to the sixth aspect of the invention, a lower mold and an upper mold having a recess having a size capable of mounting the semi-solid metal are provided, and the space formed by the slide core is filled with the semi-solid metal as necessary. A die for molding a casting product by molding, and in the case of manufacturing a casting having a hollow portion, the upper die is a void of 0.5 mm to 10 mm between the upper and lower dies of the portion corresponding to the hollow portion of the casting product. A mold for a semi-solid metal product which has an upper mold convex portion for forming a mold and can be press-molded during or after filling the semi-solid metal placed in the lower mold concave portion into the mold. The structure.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of the method for forming a semi-solid metal according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is an explanatory view showing that the upper and lower molds are closed and then the semi-solidified metal placed in the recess of the lower mold is compressed by a pressure pin to be molded, and FIG. 2 is the mold is closed in advance. FIG. 3 is an explanatory view showing that the semi-solidified metal is placed in the lower mold recess in this state and then the metal is compressed by a pressure pin to be molded, and FIG. FIG. 4 is an explanatory view showing that the lower die is compressed and molded, FIG. 4 is an explanatory view showing that the upper die having a convex portion descends and compresses and molds the semi-solidified metal of the lower die concave portion, and FIG. FIG. 6 is an explanatory view showing that the upper die descends and compresses and molds semi-solidified metal in the recess of the lower die in a die constituted by the lower die and the slide core. In the mold, the upper mold descends and compresses the semi-solid metal in the lower mold recess, and then the lower mold recess is locally localized. Pressure and explanatory view showing that separation and removal of the same site from the product, 7 is an explanatory view of a process until the production of semi-solid metal from the melt.

First, referring to (1) and (2) in FIG. 1, the upper and lower molds are closed, and then the semi-solidified metal placed in the lower mold recess is compressed by a pressure pin to be used for molding. Show an overview. 1 is an upper mold, 2 is a lower mold, 3 is a lower mold recess, 4 is a semi-solid metal, 5 is a pressure pin, 6 is a product, 7 is a runner, 8 is a biscuit part,
Reference numeral 9 is a metal inflow groove, and 10 is an upper die convex portion. Figure 1
As shown in (1), the molds 1 and 2 are open (see FIG. 1).
In (1)), the solid phase ratio in the lower mold recess 3 is 30% to 99.9.
%, The semi-solid metal 4 having fine spherical crystals is inserted and immediately the upper mold 1 descends to close both molds 1 and 2 (FIG. 1).
(2)).

Immediately after the mold is closed, the pressing pin 5 descends to compress the semi-solidified metal 4. As a result, the semi-solidified metal 4 is filled in the mold through the inflow groove 9 and the runner portion 7 opened in a part of the lower mold recess 3. When the semi-solid metal 4 is filled in the mold, the semi-solid metal 4 passes through a gap S between the upper mold convex portion 10 and the lower mold 2 to mold a molded product.

Using (1) and (2) of FIG. 2, the solid fraction of the lower mold recess 10 is 30% to 30% when both molds are closed in advance.
An outline of when the semi-solidified metal 4 having 99.9% fine spherical crystals is placed and then the metal 4 is compressed by the pressure pin 5 to be molded will be described.

1 is an upper mold, 2 is a lower mold, 3 is a lower mold recess, 4 is a semi-solid metal, 5 is a pressure pin, 6 is a product, 7 is a runner part, 8 is a biscuit part, and 9 is a metal inflow. The groove 10 is an upper convex portion. Both molds 1 and 2 are closed (Fig. 2
In (1), the semi-solidified metal 4 is inserted into the lower mold recess 3, and the pressure pin 5 immediately descends to compress the semi-solidified metal 4.

As a result, the semi-solidified metal 4 is filled in the mold through the inflow groove 9 and the runner portion 7 formed in a part of the lower mold recess 3 (FIG. 2 (2)). When the semi-solid metal 4 is filled in the mold, the semi-solid metal 4 passes through a gap S between the upper mold convex portion 10 and the lower mold 2 to mold a molded product.

FIG. 3 shows that the upper mold having no large convex portion descends and the semi-solid metal in the concave portion of the lower mold is largely compressed and molded. 1 is an upper mold, 2 is a lower mold, 3 is a lower mold recess, 4 is a semi-solid metal, and 6 is a product. In the state where the upper mold 1 and the lower mold 2 are opened (FIG. 3 (1)), the solid fraction is 30 in the lower mold recess 3.
% To 99.9% of semi-solid metal 4 having fine spherical crystals is placed, and immediately the upper mold 1 descends to compress the semi-solid metal 4 (FIG. 3 (2)) to form a molded product. It After that, the lower mold contact portion of the lower mold recess 3 is cut and removed to obtain a product 6.

An example of compression-molding the semi-solidified metal in the recess of the lower mold by lowering the upper mold will be described with reference to FIG. Reference numeral 1 is an upper die, 2 is a lower die, 3 is a lower die concave portion, 4 is a semi-solid metal, 6 is a product, and 10 is an upper die convex portion. The state where the upper mold 1 and the lower mold 2 are opened (Fig. 4
In (1)), the solid fraction in the lower mold recess 3 is 30% to 99.
Placing a semi-solid metal 4 having 9% fine spherical crystals,
Immediately, the upper mold 1 descends and compresses the semi-solid metal 4 (see FIG.
(2)) and the molded product is molded. After this, the lower mold recess 3
The lower die contact portion is cut and removed to obtain the product 6.

An example in which the semi-solidified metal in the recess of the lower mold is compression-molded by lowering the upper mold will be described with reference to (1) and (2) of FIG. 1
Is an upper mold, 2 is a lower mold, 3 is a lower mold recess, 4 is a semi-solid metal, 5
Is a pressure pin, 6 is a product, 10 is an upper die convex portion, and 11 is a slide core. 4 arranged radially on the upper surface of the lower mold 2.
In a state where the slide core 11 composed of one piece of mold is advanced, fine spherical crystals having a solid fraction of 30% to 99.9% are placed in the lower mold recess 3 located at the center of the lower mold 2. The semi-solidified metal 4 is placed (FIG. 5 (1)), the upper mold 1 immediately descends to compress the semi-solidified metal 4 (FIG. 5 (2)), and the pressing pin 5 is used as necessary. The semi-molten metal 4 in the lower mold recess 3 is compressed. Further, the molded product is molded by passing through the gap S between the upper mold convex portion 10 and the lower mold. After that, the lower mold contact portion of the lower mold recess 3 is cut and removed to obtain a product 6.

An example in which the semi-solid metal in the recess of the lower mold is lowered and compressed by the upper mold and then the region of the recess of the lower mold is locally pressed to separate and remove the same from the product will be described with reference to FIG. 1 is an upper mold, 2 is a lower mold, 3 is a lower mold recess, 4 is a semi-solid metal, 5 is a pressure pin, 6 is a product, 11 is a slide core, and 12 is a lower mold holding block.

In a state where the slide core 11 composed of four pieces of dies radially arranged on the upper surface of the lower mold 2 is advanced (FIG. 6 (1)), it is fixed in the lower mold recess 3. Phase ratio is 30%
Place the semi-solidified metal 4 having -99.9% fine spherical crystals, immediately lower the upper mold 1 to compress the semi-solidified metal 4 (Fig. 6 (2)), and pressurize as necessary. The pin 5 locally compresses the semi-solidified metal 4 in the lower mold recess 3 (FIG. 6C), and the lower mold holding block 12 descends to separate and remove the same part from the product 6. Further, the molded product is molded by passing through the gap S between the upper mold convex portion 10 and the lower mold 2. After that, the lower mold contact portion of the lower mold recess 3 is cut and removed to obtain a product 6.

(Embodiment) The embodiment of the present invention will be described in detail below with reference to the drawings.

When the semi-solidified metal 4 placed on the lower mold 2 is pressurized, a solidified layer generated by contacting the lower mold 2 and lowering the temperature is mixed inside the product 6 and produced in the container. Since the oxide of the semi-solidified metal 4 cannot be fixed, it is mixed in the product 6 and is a quality problem. Further, when the semi-solid metal 4 placed on the lower mold 2 is pressurized, it is below the portion of the hollow portion of the cast product 6 (the hollow portion here refers to a through hole communicating from the front side to the back side of the product). Since the semi-solidified metal 4 enters into the initial gap between the mold 2 and the upper mold 1 during pressurization and solidifies, the product 6 having a desired thickness cannot be obtained because it cannot be pressed even by press molding. .

Next, Table 1 shows the molding conditions and the quality of the molded product.

[0027]

[Table 1]

The alloy used is an AC4CH alloy. The alloy composition is Al-7%, Si-0.35%, Mg-0.15.
Ti. The semi-solid metal 4 of Examples 1 to 4 is a stainless steel holding container 14 directly made of about 1.5 kg of an alloy whose superheat is maintained at 30 ° C. against the liquidus temperature without using a cooling jig. It was obtained by pouring the molten metal into, and cooling it to a molding temperature showing a predetermined liquid phase ratio, and maintaining it at a temperature showing a 50% solid phase ratio for about 3 minutes, for example.

Ceramics having a heat insulating property were arranged on the upper and lower parts of the container, and the exposed part of the container was cooled by air 16 to obtain a semi-solid metal 4 having a uniform temperature. In Examples 5 to 10 and Comparative Examples 1 to 5, the molten metal poured into the holding container was about 7 kg. The holding time was about 5 minutes until the temperature at which the solid fraction was 50%. The mold used for the test was 200 ° C., and a graphite-based water-soluble mold release agent was used. For the 1.5 kg product, a machine with a mold clamping force of 350 t is used, and for the 7 kg product,
A machine having a mold clamping force of 800 t was used.

The method of manufacturing the semi-solid metal 4 is not limited, and various methods can be applied.
The method used in the examples is a method of obtaining directly without using a jig, and is an aluminum alloy molten metal containing a crystal refining agent having a superheat degree of less than 50 ° C. with respect to a liquidus temperature, or The magnesium alloy melt is poured directly into the holding container (metal container 14) via the ladle 13 without using a cooling jig, crystal nuclei are generated in the melt 19, and the crystal nuclei are grown to give a predetermined liquid. 3 while cooling to the molding temperature showing the phase ratio
The semi-solidified metal 4 having spherical crystals is obtained by holding the semi-solidified metal 4 for 0 second to 30 minutes, and the semi-solidified metal 20 is inverted from the container 14 and discharged to be placed in a mold.

Further, the molten metal 19 is brought into contact with a cooling plate, or the molten metal 19 for pouring a cooling vibrating rod is continuously immersed in the molten metal 19 after pouring and cooled in a holding container in the same manner as the above method. A holding method can also be applied.

The semi-molten metal 20 obtained by heating the billet once solidified is also applicable to the present invention. In Comparative Example 1, since the lower mold 2 has no recess, when the semi-solidified metal 4 is placed and pressed, the solidified layer generated by contacting the lower mold 2 and lowering the temperature is inside the product 6. In addition to being mixed, since the oxide of the semi-solidified metal 4 generated in the container cannot be fixed, it is mixed in the product 6 as well, which is a quality problem.

In Comparative Example 2, the initial gap S between the lower mold 2 and the upper mold 1 at the portion of the cavity of the cast product (the cavity here is the through hole communicating from the front side to the back side of the product). When the semi-solid metal 4 is pressed due to its narrowness, the initial gap cannot be compressed and the product 6 is thicker than the initial gap, so that a gap S is generated between the lower mold 2 and the upper mold 1 to cause burrs. However, the product of the target size could not be obtained.

In Comparative Example 3, since the product 6 is thick,
The amount of cutting after forming is large and the yield is poor. Comparative Example 4
Since the solid phase ratio is low, even if the semi-solid metal 4 is placed in the lower mold recess 3, the semi-solid metal 4 flows to a place other than the lower mold recess 3 so that a solidified layer is likely to be formed, Since the oxide of the semi-solidified metal 4 generated in 1 cannot be fixed to the lower mold recess 3, there is a problem in quality.

In Comparative Example 5, since it is completely solid and the temperature is low, molding is not easy. On the other hand, Examples 1 to 1
In 0, a solidified layer and an oxide layer were collected in a part, cut as required, and a product having a cavity in a cast product could be formed, so that a high quality product could be obtained. .

[0036]

As is apparent from the above description,
In the method for forming a semi-solid metal product according to the present invention, (1)
The semi-solid metal is placed in the recess of the lower mold, and the product space formed by moving the upper mold and the lower mold and, if necessary, the slide core is filled with the semi-solid metal. When the product quality is affected, the part that comes into contact with the lower mold recess is removed by cutting, and (2) when molding a product having a cavity, the cavity provided in the upper mold is formed. By setting the interval between the upper die convex portion having a portion to be formed and the lower die to be 0.5 mm to 10 mm, and cutting the portion corresponding to the hollow portion after casting, and penetrating by cutting.
It is possible to obtain a high-quality molded product in which the solidified layer and the oxide layer are not mixed in the product.

[Brief description of drawings]

FIG. 1 is an explanatory view showing that a semi-solidified metal placed in a lower mold recess is compressed by a pressure pin and then molded after closing upper and lower molds.

FIG. 2 is an explanatory view showing that a semi-solidified metal is placed in the lower mold recess in a state where the mold is closed in advance, and then the metal is compressed by a pressure pin to be molded.

FIG. 3 is an explanatory view showing that the semi-solidified metal of the concave portion of the lower die is molded by descending and compressing the upper die having no large convex portion.

FIG. 4 is an explanatory diagram showing that the semi-solidified metal in the recess of the lower mold is lowered and compressed by the upper mold to be molded.

FIG. 5 is an explanatory view showing that a semi-solid metal in a recess of a lower mold is compressed by an upper mold to be compressed and molded in a mold constituted by a lower mold and a slide core.

FIG. 6 is a mold configured by a lower mold and a slide core, in which the upper mold descends and compresses the semi-solid metal in the lower mold recess,
It is explanatory drawing which shows that the site | part of a lower mold recessed part is locally pressed after that, and the same site is separated and removed from a product.

FIG. 7 is an explanatory diagram of a process for producing a semi-solid metal from a molten metal.

[Explanation of symbols]

1 Upper mold 2 Lower mold 3 Lower mold recess 4 Semi-solid metal 5 Pressure pin 6 products 7 Runner section 8 biscuits 9 Metal inflow groove 10 Upper mold protrusion 11 slide core 12 Lower presser block 13 ladles 14 metal containers 15 Insulation 16 air 17 High frequency heating coil 18 injection sleeve 19 molten metal 20 semi-solid metal

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B22D 27/09 B22D 27/09 A 27/11 27/11 27/20 27/20 Z 29/00 29/00 G 31 / 00 31/00 A (72) Takuma Maeda Tayama Maeda, Ube City, Yamaguchi Prefecture 1980, Ogishi-oki, Ogishi Oyama, Ube Machinery Co., Ltd. F-term (reference) 4E093 NA01 NB01 NB10

Claims (6)

[Claims] 1. A semi-solidified metal having fine spherical crystals with a solid fraction of 30% to 99.9% is placed in the recess of the lower mold, and the upper mold and the lower mold and, if necessary, the movement of the slide core. A method for molding a semi-solid metal product, comprising filling the semi-solid metal in a product space formed by the method. 2. When the upper mold is filled with the semi-solidified metal by compressing the semi-solidified metal as it approaches the lower mold, the upper mold has a portion for forming a cavity. The molding method according to claim 1, wherein the interval between the upper die convex portion and the lower die is set to 0.5 mm to 10 mm, and a portion corresponding to the hollow portion is cut and cut through after casting. 3. An upper die convex portion having a portion forming a cavity portion provided in the upper die when the semi-solid metal filled in the die after closing the upper and lower die is compressed by a pressure pin. The molding method according to claim 1, wherein a distance between the lower mold and the lower mold is set to 0.5 mm to 10 mm, and a portion corresponding to the hollow portion is cut and cut to penetrate after casting. 4. A local pressurizing by site pressurizing pin of the lower die recess of semi-solidified metal filled into the product space formed by the upper and lower molds, to separate and remove the site from the product if necessary The molding method according to claim 1 or 2, which is characterized in that. 5. The method according to claim 1, wherein the lower mold contact portion of the lower mold recess of the semi-solidified metal filled in the product space formed by the upper and lower molds is cut and removed. The molding method according to claim 4. 6. A casting comprising a lower mold and an upper mold having recesses each having a size capable of mounting the semi-solid metal, and further filling the space formed by the slide core with the semi-solid metal, if necessary. A die for molding a product, and in the case of manufacturing a casting having a hollow portion, the upper die is 0.5 mm to 1 between the upper and lower dies of a portion corresponding to the hollow portion of the casting product.
A semi-solid metal product having an upper die convex portion so as to form a void of 0 mm and capable of press-forming when the semi-solid metal placed in the lower die concave portion is filled in the die or after the die is filled. Molding die.