JP2007222912A - Die for casting aluminum foil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a die for casting aluminum foil where the vicinity of the outlet of a gate and the surface part of a hub section whose temperature is particularly made high are effectively cooled to reduce cooling time in casting, and also, to reduce the amount of the release agent to be atomized, thus the service life of a die is elongated, and further, the generation of a defective product can be prevented. <P>SOLUTION: The die for casting aluminum foil is provided with: a lower die 1 in which a cylindrical projecting part 14 provided at the lower face of the central part in a designed die 2 and a recessed part provided at the upper face of the central part in a backup die 3 are engaged, so as to be fixed. Further, the die is equipped with: ring-shaped passages 16a, 16b for a cooling medium in upper and lower two steps provided at the circumferential part of the projecting part 14 in the designed die 2; a vertical passage 16c for a cooling medium provided at the inside of a bolt hole projecting part 15 in the designed die 2 and directly communicated with the upper ring-shaped passage 16a for a cooling medium; and an inside passage 16d for a cooling medium whose upper edge is arranged in the vertical passage 16c for a cooling medium and whose lower edge is directly communicated with the lower ring-shaped passage 16b for a cooling medium. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an aluminum wheel casting mold and an aluminum wheel casting apparatus provided with the aluminum wheel casting mold, and more specifically, an aluminum wheel casting mold capable of preventing a local temperature rise of the mold. The present invention relates to an aluminum wheel casting apparatus including a mold and an aluminum wheel casting mold.

  In order to prevent a local temperature rise of the casting mold, it is generally desirable to provide a passage through which a cooling medium passes near a portion where the temperature in the mold becomes high. It may be difficult to provide a passage for the cooling medium near the destination location.

  For example, in the case of a mold for an aluminum wheel, the gate for filling the mold cavity with molten metal is in the center, and the hub part of the aluminum wheel is thick. Despite the large rise, it is difficult to provide a passage for the cooling medium in this portion. In particular, in a mold in which the offset of the mounting surface of the aluminum wheel is small and the central part of the lower mold is raised and thick (for example, see FIG. 5 of Patent Document 1), the hub surface is close to the gate outlet. It is difficult to provide a passage for the cooling medium in a nearby portion, and the temperature near the surface of the central portion of the mold becomes very high due to the amount of heat released from the molten metal.

  When the temperature at the center of the mold becomes extremely high, a release agent mixed with water is sprayed on the gate part for release during casting, but the release agent repels and adheres poorly, and the spray amount When there is a large amount of water, the surrounding surface rapidly cools due to the latent heat of the water, but there is a time delay in the heat conduction of the mold, so the temperature inside the mold remains high and the temperature between the mold surface and the inside is high. The difference becomes very large, and a large tensile thermal stress is generated on the surface, which causes cracks due to repetition. On the other hand, if such a mold release agent is not sprayed, the cooling and solidification time of the molten metal in the cavity becomes longer during casting, the casting cycle time becomes longer, and the productivity is poor.

  In order to solve these problems, the present inventor has proposed an aluminum wheel casting mold (see Patent Document 1, FIG. 4 and the like in this specification), but in cooling a high bolt hole protrusion when the hub thickness is thick. Is still inadequate, necessitating the spraying of a large amount of release agent for cooling, and a large thermal stress is generated thereby shortening the life of the mold. Furthermore, spraying of a large amount of release agent reduces the mold surface temperature of the spokes, resulting in poor product flow due to poor hot water flow, and product failure due to uneven spraying of the release agent. It was.

Japanese Patent No. 3411733

  The object of the present invention is to effectively cool the vicinity of the gate outlet and the surface of the hub portion, which are particularly high in the mold, to shorten the cooling time for casting, and to reduce the spray amount of the release agent. This reduces the thermal stress applied to the mold and prolongs the service life of the mold, and also prevents the occurrence of defective products by preventing uneven cooling and partial overcooling. An object of the present invention is to provide a casting mold and an aluminum wheel casting apparatus provided with such a mold.

  As a result of diligent research to solve the above-mentioned problems, the present inventors have found that a lower mold of an aluminum wheel casting mold, that is, a stationary mold, has a cylindrical concave and convex fitting portion at the center on the upper surface side. The core is divided into two disk-shaped molds consisting of a design mold on the lower surface and a backup mold on the lower surface, and a cylindrical protrusion at the lower center of the design mold on the upper surface side is fitted into a recess in the backup mold on the lower surface side. In this portion, a two-stage ring-shaped cooling medium passage is formed in this portion, and a cooling medium vertical passage communicating with the upper-stage ring-shaped cooling medium passage is formed in the design-type bolt hole protrusion. In the cooling medium vertical passage, there is provided a cooling medium internal passage that communicates with the lower ring-shaped cooling medium passage and extends vertically, and the cooling medium is introduced into the cooling medium vertical passage. High-temperature design-type bolt holes In addition to cooling the starting portion, the cooling medium passing through the upper and lower two-stage ring-shaped cooling medium passages can cool the vicinity of the high-temperature gate, thereby shortening the cooling time for casting. In addition, it has been found that it is possible to eliminate the need for spraying an excessive release agent, to reduce the temperature difference between the inside and outside of the gate part, to prevent the occurrence of surface cracks due to thermal stress, and to prevent the occurrence of product defects. The present invention has been completed.

  That is, the present invention is divided into (1) an upper design mold and a lower backup mold, and is provided on the upper surface of the central part of the backup mold and the cylindrical projection provided on the lower surface of the central part of the design mold. An aluminum wheel casting mold provided with a lower mold that is fitted and fixed to the recessed portion, wherein the upper and lower two-stage ring-shaped cooling medium passages are provided around the convex portion of the design mold, The cooling medium vertical passage provided directly in the upper ring-shaped cooling medium passage provided in the design-type bolt hole protrusion, and the upper end thereof is disposed in the cooling medium vertical passage. And an aluminum wheel casting mold having a lower end provided with a cooling medium internal passage provided in direct communication with the lower ring cooling medium passage, and (2) a lower ring cooling. If the cooling medium introduction passage is connected to the medium passage, The cooling medium discharge passage is connected to the upper ring-shaped cooling medium passage, and the cooling medium includes the cooling medium introduction passage, the lower ring-shaped cooling medium passage, the cooling medium internal passage, the cooling medium vertical passage, and the upper stage. The ring-shaped cooling medium passage and the cooling medium discharge passage are configured to pass through in this order.

  In the present invention, (3) a cooling medium introduction passage is connected to the upper ring-shaped cooling medium passage, a cooling medium discharge passage is connected to the lower ring-shaped cooling medium passage, and the cooling medium is The cooling medium introduction passage, the upper ring cooling medium passage, the cooling medium vertical passage, the cooling medium internal passage, the lower ring cooling medium passage, and the cooling medium discharge passage are configured in this order. The aluminum wheel casting mold as described in (1) above, and (4) a passage for the outer ring-shaped cooling medium below the rim portion of the mold, on the mating surface of the design mold and the backup mold. The aluminum wheel casting mold according to any one of (1) to (3), wherein (5) a cooling medium introduction passage and a cooling medium discharge passage are provided in a backup mold. It is characterized by being The aluminum wheel casting mold according to any one of (1) to (4) and (6) the thickness of the design mold below the spoke part is 30 mm or less, (1) to (1) In the above (1), an air gap is provided on the mating surface of the aluminum wheel casting mold according to any one of (5) and (7) the design mold and the backup mold below the spoke portion. (6) An aluminum wheel casting apparatus comprising the aluminum wheel casting mold according to (6) and (8) the aluminum wheel casting mold according to any one of (1) to (7). .

  According to the aluminum wheel casting mold of the present invention and the aluminum wheel casting apparatus provided with such a mold, the vicinity of the gate outlet and the surface of the hub portion, which are particularly high in the mold, are effectively cooled, thereby cooling the casting. By shortening the time and reducing the spray amount of the release agent, the thermal stress applied to the mold is reduced to prolong the service life of the mold, and uneven cooling and partial Overcooling can be prevented and the occurrence of defective products can be prevented.

  The aluminum wheel casting mold of the present invention is divided into an upper design mold and a lower backup mold, and is provided with a cylindrical convex portion provided on the lower surface of the central portion of the design mold and the central portion of the backup mold. An aluminum wheel casting mold having a lower mold fitted and fixed to a concave portion provided on the upper surface of the upper and lower rings formed in the upper and lower stages provided on the periphery of the convex portion of the design mold A medium passage, a cooling medium vertical passage directly connected to the upper ring-shaped cooling medium passage provided inside the plurality of bolt hole protrusions of the design type, and the cooling medium vertical passage. The aluminum wheel casting mold is particularly limited as long as the tip is disposed and the other end has a cooling medium internal passage provided in direct communication with the lower ring-shaped cooling medium passage. Rather, the lower ring cooling medium passage The cooling medium introduction passage is connected to the upper ring cooling medium passage, and the cooling medium discharge passage is connected to the upper ring cooling medium passage. The cooling medium is the cooling medium introduction passage, the lower ring cooling medium passage, and the cooling medium. The internal passage for cooling, the vertical passage for cooling medium, the passage for the upper ring-shaped cooling medium, and the cooling medium discharge passage may pass through in this order, and the cooling medium introduction passage is connected to the upper ring-shaped cooling medium passage. The cooling medium discharge passage is connected to the lower ring-shaped cooling medium passage, and the cooling medium is provided as the cooling medium introduction passage, the upper ring-shaped cooling medium passage, the cooling medium vertical passage, and the cooling medium. The internal passage, the lower ring-shaped cooling medium passage, and the cooling medium discharge passage may be passed in this order.

  According to the present invention, when casting is performed by filling a mold cavity with a molten metal, a thick portion such as a central gate portion and a hub portion of the die, particularly, a portion where the bolt hole protrusion of the hub portion is high. The local temperature rise can be prevented. As a result, the cooling time for casting can be shortened, and the spray amount of the release agent can be reduced, thereby reducing the thermal stress applied to the mold and extending the service life of the mold. Can be achieved. In addition, it is possible to prevent generation of defective products due to non-uniform spraying such as generation of a lump of release agent. Furthermore, it is possible to prevent overcooling, improve the flow of hot water in a thin portion such as a spoke portion where the cooling easily proceeds, and prevent the occurrence of defective products.

  In addition, the aluminum wheel casting mold of the present invention is obtained by dividing the lower mold into two disk-shaped molds, that is, a design mold on the upper surface side and a backup mold on the lower surface side. Is divided into low-temperature parts, the temperature difference in the mold in each of them is significantly smaller than in the conventional integrated type, the thermal stress generated in the whole mold is reduced, and the large crack of the mold The possibility is greatly reduced. In addition, since the design mold and the backup mold are fitted and fixed by a cylindrical convex portion provided on the lower surface of the central portion of the design mold and a concave portion provided on the upper surface of the central portion of the backup mold, Misalignment can be prevented.

  In the cylindrical convex portion provided on the lower surface of the central portion of the design mold, for example, the inner diameter corresponding to the casting port and the gate portion is about 40 to 65 mm, and the outer diameter is about 90 to 100 mm. Its height is about 25 to 45 mm. In the mold for casting an aluminum wheel according to the present invention, a two-stage ring-shaped cooling medium passage is provided in the convex portion, and the two-stage ring-shaped cooling medium passage is only a groove formed in the convex portion. It may be constituted by connecting this groove and the groove formed in the back-up type concave part.

  Further, the cooling passage constituted by the two-stage ring-shaped cooling medium passage, the cooling medium vertical passage, and the cooling medium internal passage may be, for example, two steps from the design-shaped convex portion to the bolt hole protrusion portion. By drilling through the ring-shaped cooling medium passage, a vertical cooling medium passage is formed inside the bolt hole projection, and an inner pipe for cooling medium is inserted into the drilling portion, and is fixed and fixed as appropriate. By sealing, it can be formed easily.

  Further, in the aluminum wheel casting mold of the present invention, it is preferable that an outer ring-shaped cooling medium passage is provided below the rim portion of the mold and on the mating surface of the design mold and the backup mold. . The part where the spoke part and rim part of the mold intersect is thick, and by providing a cooling medium passage in the vicinity of this part, the cooling time for casting can be further shortened and the thermal stress applied to the mold The service life of the mold can be prolonged by reducing the size.

  Further, the two-stage ring-shaped cooling medium passage provided in the peripheral portion of the convex portion, and the cooling medium introduction passage and the cooling medium discharge passage communicating with the outer ring-shaped cooling medium passage may be provided in the design mold. However, it is preferable to provide a backup mold having a relatively low temperature from the viewpoint of suppressing damage to the mold. A plurality of these cooling medium introduction passages and cooling medium discharge passages may be provided for cooling balance. This also makes it possible to make the design mold thinner, prevent overcooling of the portion where the cooling of the spoke portion and the like is likely to proceed, improve the hot water flow, and prevent the occurrence of defective products. The thickness of the design mold can be, for example, 30 mm or less, preferably 20 to 30 mm, in the portion below the spoke portion. Since the backup mold has a low temperature and a small thermal stress, the increased stress is small even if the cooling medium introduction passage and the cooling medium discharge passage are provided, and there is no problem such as breakage of the mold.

  Moreover, in the metal mold | die for aluminum wheel casting of this invention, it is preferable that the space | gap is provided in the mating surface of the design type | mold and backup type | mold below a spoke part. Thereby, the cooling from the backup mold can be reduced, the mold surface temperature can be increased, and the hot water flow in the thin-spoke surface portion can be improved.

  Hereinafter, the present invention will be described more specifically with reference to the drawings. However, the technical scope of the present invention is not limited to this example. 1 is a schematic sectional view of an aluminum wheel casting apparatus according to an embodiment of the present invention, FIG. 2 is a plan view of a lower mold of the aluminum wheel casting apparatus shown in FIG. 1, and FIG. 2 is an enlarged view of a periphery of a cooling medium passage of the aluminum wheel casting apparatus shown in FIG.

  As shown in FIGS. 1 to 3, an aluminum wheel casting apparatus according to an embodiment of the present invention includes a lower mold 1 and an upper mold 4, and the lower mold 1 includes a design mold 2 and a lower surface on the upper surface side. The back-up type 3 on the side is divided into upper and lower parts. A vertical gate portion 8 is formed at the center of the design die 2 and the backup die 3. The design die 2 and the backup die 3 are fitted with a cylindrical convex portion 14 provided on the lower surface of the central portion of the design die 2 and a concave portion provided on the upper surface of the central portion of the backup die, and a window portion of the aluminum wheel. It is fixed by a fastening bolt 24 at a position 26 (see FIG. 2) so that misalignment between the design die 2 and the backup die 3 can be prevented. Reference numeral 5 represents a slide core that forms a mold cavity 10 in cooperation with the lower mold 2 and the upper mold 4, and reference numerals 6 and 7 represent casting sleeves for casting molten metal from below, The injection plunger is represented, and a reference numeral 9 represents a gate cutting pin that is inserted into the gate portion 8 to close the gate portion 8.

  As shown in FIGS. 1 and 3, the outer periphery of the cylindrical convex portion 14 provided on the lower surface of the central portion of the design die 2 is provided with two upper and lower grooves, and two steps arranged vertically. Ring-shaped coolant passages 16a and 16b are formed. Further, as shown in FIGS. 2 and 3, the bolt holes of the design die 2 are formed by drilling through the two-stage cooling medium passages 16 a and 16 b formed on the outer periphery of the convex portion 4 of the design die 2. A vertical cooling medium passage 16c is formed inside the protrusion 15, and a vertical cooling medium inner pipe 16d having a small diameter is inserted into the perforated portion. The inner pipe 16d for the vertical cooling medium has a lower end directly communicating with the lower ring-shaped cooling medium passage 16a, and an upper end thereof is an upper end of about 2 to 8 mm from the upper end in the vertical passage for the cooling medium. It is fixed so that it is located in the vicinity. Specifically, the inner pipe 16d for the vertical cooling medium has a portion of the middle stage partition plate 14a positioned between the lower ring-shaped cooling medium passage 16a and the upper ring-shaped cooling medium path 16b. It is sealed and fixed by matching the diameter of the passage 16c. Further, the opening on the lower surface of the lower ring-shaped cooling medium passage 16a is appropriately sealed. Thereby, efficient cooling of the periphery of the gate part 8 and the bolt hole projection part 15 that are particularly high in temperature is enabled.

  Further, an inner cooling medium introduction passage 19 provided in the backup mold 3 is provided in communication with the lower ring-shaped cooling medium passage 16a, and the lower ring is interposed via the inner cooling medium introduction passage 19. A cooling medium is introduced into the channel-like cooling medium passage 16a. Further, an inner cooling medium discharge passage 20 provided in the backup mold 3 is communicated with the upper ring-shaped cooling medium passage 16b, and the inner cooling medium is passed through the inner cooling medium discharge passage 20. The cooling medium introduced from the introduction passage 19 is discharged from the upper ring-shaped cooling medium passage 16b. That is, the cooling medium includes an inner cooling medium introduction passage 19, a lower ring cooling medium passage 16a, a vertical cooling medium inner pipe 16d, a vertical cooling medium passage 16c, an upper ring cooling medium passage 16b, and an inner side. It passes through the cooling medium discharge passage 20 in this order.

  The inner cooling medium introduction passage 19 is an inner cooling medium discharge passage, the inner cooling medium discharge passage 20 is an inner cooling medium introduction passage, and the cooling medium is an inner cooling medium introduction passage, an upper ring-shaped cooling medium passage 16b, The vertical cooling medium passage 16c, the vertical cooling medium inner pipe 16d, the lower ring-shaped cooling medium passage 16a, and the inner cooling medium discharge passage may be passed in this order.

  Further, below the rim portion of the mold, the mating surfaces of the design mold 2 and the backup mold 3 are provided with arc-shaped grooves to form a ring-shaped outer cooling medium passage 17. That is, the ring-shaped groove provided on the lower surface of the design die 2 and the ring-shaped groove provided on the upper surface of the backup die 3 are aligned with each other to constitute the outer ring-shaped cooling medium passage 17. In the outer ring-shaped cooling medium passage 17, an outer cooling medium introduction passage 21 and an outer cooling medium discharge passage 22 provided in the backup mold 3 are provided in communication with each other via the outer cooling medium introduction passage 21. The cooling medium is introduced into the ring-shaped outer cooling medium passage 17, and the cooling medium is discharged through the outer cooling medium discharge passage 22. Note that packings 23 such as O-rings are provided on both sides of the ring-shaped cooling medium passages 16 and 17, respectively, to prevent leakage of the cooling medium. Further, these packings 23 are provided in the vicinity of the cooling medium passages 19 to 22, and the temperature rise in the portions is not so high, so that they are not damaged by ordinary materials. In addition, you may provide the leaking liquid discharge channel | path 25 as needed.

  In the aluminum wheel casting apparatus according to the embodiment of the present invention, the design die 2 and the backup die 3 below the spoke portion 27 between the two-stage ring-shaped cooling medium passage 16 and the outer cooling medium passage 17. A gap 18 is provided on the mating surface. By providing the gap 18, the heat of this part of the design die 2 is not transmitted to the backup die 3, and the thickness of the spoke surface is reduced to reduce the heat radiation of the aluminum in order to reduce the weight of the aluminum wheel. The temperature of the mold surface in this part rises, and a good molten metal flow can be secured.

  Further, in the design die 2, the thickness h of the thin portion below the spoke portion is reduced to 30 mm or less. As a result, the overall temperature difference can be reduced, and the cooling medium passages 19 to 22 are provided in the backup mold 3, so that the design mold 2 does not have a place where stress concentration of thermal stress occurs, and the mold Can be prevented from being damaged. On the other hand, the back-up mold 3 has only a central portion in contact with the molten metal 11, and only a compressive stress is generated even if the temperature rises. The temperature rise in other portions is small, the thermal stress is small, and the cooling medium passage 19. Even if ~ 22 is provided, it does not lead to breakage. In particular, when this method is used for low-pressure casting, a separate piece of inlet guide is installed under the gate portion 8, so that the temperature rise of the backup mold 3 is further reduced.

  As described above, in the aluminum wheel casting apparatus according to the embodiment of the present invention, the lower mold 1 is divided into the design mold 2 and the backup mold 3, and the ring-shaped coolant passage 16 is formed in the gate portion 8. Since the heat amount from the bolt hole protrusion 15 of the hub which is close to the hub surface 13 and the feeder 12 and is likely to be overheated is carried away by the flow of the cooling medium, it can be installed in the desired cooling area. The mold surface temperature can be set to an appropriate temperature. Therefore, when the mold release agent is sprayed, the amount of water for cooling is small, the mold surface is not excessively cooled, the generated thermal stress is not so much, the generation of cracks is reduced, and the life is extended. In addition, it is possible to eliminate the occurrence of defects on the product surface due to the generation of a release agent lump. Similarly, the ring-shaped outer cooling medium passage 17 can also be designed with an appropriate distance and area to absorb the heat radiation from the cavity 10.

It is a schematic sectional drawing of the aluminum wheel casting apparatus which concerns on one Embodiment of this invention. It is a top view of the lower metal mold | die of the aluminum wheel casting apparatus shown in FIG. FIG. 2 is an enlarged view of a periphery of a cooling medium passage of the aluminum wheel casting apparatus shown in FIG. 1. It is an enlarged view around the passage for cooling media of the conventional aluminum wheel casting device.

Explanation of symbols

1 Lower mold (fixed mold)
2 Design mold 3 Backup mold 4 Upper mold (movable mold)
5 Slide core 6 Injection sleeve 7 Injection plunger 8 Gate part 9 Gate cutting pin 10 Cavity 11 Molten metal (cast)
12 Feeding hot water 13 Hub surface 14 Cylindrical convex part (cylindrical protrusion)
14a Middle partition plate 14b Lower partition plate 15 Bolt hole projection 16a Ring-shaped cooling medium passage (lower)
16b Ring-shaped cooling medium passage (upper stage)
16c Cooling medium vertical passage 16d Cooling medium inner tube 17 Outer ring-shaped cooling medium passage 18 Gap 19 Inner cooling medium introduction passage 20 Inner cooling medium discharge passage 21 Outer cooling medium introduction passage 22 Outer cooling medium discharge passage 23 Packing 24 Fastening Attached bolt 25 Leakage liquid discharge passage 26 Window portion 27 Spoke portion 28 Gate portion 29 Hub surface 30 Cylindrical convex portion (cylindrical protrusion)
31 Bolt hole projection 32 Ring-shaped cooling medium passage 33 Outer ring-shaped cooling medium passage 34 Inner cooling medium introduction passage 35 Outer cooling medium discharge passage

Claims (8)

The upper design mold and the lower backup mold are divided into two parts, and the cylindrical convex part provided on the lower surface of the central part of the design mold and the concave part provided on the upper surface of the central part of the backup mold are fitted and fixed. A mold for casting an aluminum wheel provided with a lower mold,
An upper and lower two-stage ring-shaped cooling medium passage provided on the periphery of the design-shaped convex portion;
A cooling medium vertical passage provided in the design-type bolt hole protrusion and directly communicating with the upper ring-shaped cooling medium passage;
An aluminum wheel having an upper end arranged in the vertical passage for cooling medium and an internal passage for cooling medium provided at the lower end in direct communication with the lower ring-shaped cooling medium passage Mold for casting. A cooling medium introduction passage is connected to the lower ring-shaped cooling medium passage, and a cooling medium discharge passage is connected to the upper ring-shaped cooling medium passage.
The cooling medium passes through the cooling medium introduction path, the lower ring cooling medium path, the cooling medium internal path, the cooling medium vertical path, the upper ring cooling medium path, and the cooling medium discharge path in this order. The mold for casting an aluminum wheel according to claim 1, wherein the mold is used. A cooling medium introduction passage is connected to the upper ring-shaped cooling medium passage, and a cooling medium discharge passage is connected to the lower ring-shaped cooling medium passage.
The cooling medium passes through the cooling medium introduction path, the upper ring cooling medium path, the cooling medium vertical path, the cooling medium internal path, the lower ring cooling medium path, and the cooling medium discharge path in this order. The mold for casting an aluminum wheel according to claim 1, wherein the mold is used.   The aluminum according to any one of claims 1 to 3, wherein a passage for an outer ring-shaped cooling medium is provided below the rim portion of the mold and on the mating surface of the design mold and the backup mold. Mold for wheel casting.   The aluminum wheel casting mold according to any one of claims 1 to 4, wherein the cooling medium introduction passage and the cooling medium discharge passage are provided in a backup mold.   The mold for casting an aluminum wheel according to any one of claims 1 to 5, wherein the thickness of the design mold below the spoke portion is 30 mm or less.   The aluminum wheel casting mold according to claim 1, wherein a gap is provided in a mating surface between the design mold and the backup mold below the spoke portion. An aluminum wheel casting apparatus comprising the mold for casting an aluminum wheel according to any one of claims 1 to 7.