JP2008038179A - Hot chamber die-casting machine and casting method using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently cast an aluminum-based molten metal using a hot chamber die-casting machine. <P>SOLUTION: In a hot chamber die-casting machine 1 for casting an aluminum-based molten metal 2, at least parts constituting an injection mechanism 8 for injecting the aluminum-based molten metal 2 are composed of an aluminum-based corrosion-resistant alloy metal which has a composition consisting of, by weight, 50 to 60% cobalt as a principal component, 18 to 28% chromium, 4 to 17% molybdenum, 2 to 5% nickel, 0 to 5% iron and the balance other metals. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hot chamber die casting machine for casting, for example, aluminum and an aluminum alloy, and a casting method. More specifically, the present invention makes it possible to inject an aluminum-based molten metal into a mold by a plunger and perform injection pouring. The present invention relates to an injection mechanism.

  Conventionally, when casting an alloy such as zinc, lead, and tin, a hot chamber die casting machine is used. As shown in FIG. 3, the hot chamber die casting machine 1a includes a molten metal tank 3 for storing the molten metal 2 and a heater 5 for heating the molten metal tank 3 to keep the molten metal 2 at a certain temperature or higher. A furnace body structure 4 including these, a gooseneck 9 suspended by a support such as an injection yagler 20 to the internal space of the molten metal tank 3, and a molten metal 2 filled in the cylinder portion 10a of the gooseneck 9 A plunger 12 that is press-fitted and pushed out; a drive device 23 such as a hydraulic cylinder that reciprocates the plunger 12; a nozzle 11 that guides the molten metal 2 pushed out by the plunger 12 and injects it into a mold; The nozzle 11 is formed by a nozzle heater 24 provided at the injection tip of the nozzle 11, and a fixed mold 25 and a moving mold 26 shown in FIG. 1.

The fixed mold 25 and the movable mold 26 form a mold space 27 and a runner portion 28 that communicates with the nozzle 11 and the mold space 27. In such a hot chamber die casting machine, it is suitable for casting of zinc or the like having a low melting point. However, when this is applied to an aluminum alloy, the aluminum melt reacts with most metals and corrodes. Therefore, metal cannot be used for the injection mechanism for injecting the molten aluminum. Therefore, it is known that the injection mechanism is formed of a ceramic material that is not eroded by the aluminum-based molten metal when cast by a cold chamber die casting machine (see Patent Document 1) or by casting with a hot chamber die casting machine. (See Patent Document 2).
JP 2003-53502 A JP-A-10-296420

  However, in the conventional hot chamber die casting machine, when the injection mechanism of the aluminum-based molten metal is formed of a ceramic material, there are problems that the cost increases and the product life is short. Further, the cold chamber die casting machine has a problem that the working efficiency is poor. The hot chamber die casting machine according to the present invention has been proposed in order to solve such problems.

  The gist for solving the above-mentioned problems of the hot chamber die casting machine according to the present invention is to provide a component constituting an injection mechanism for injecting at least the aluminum molten metal in a hot chamber die casting machine for casting the aluminum molten metal. The main components are 50 to 60% by weight of cobalt, 18 to 28% by weight of chromium, 4 to 17% by weight of molybdenum, 2 to 5% by weight of nickel, and 0 to 0 of iron. It is made of an aluminum-based corrosion-resistant alloy metal with 5% and the rest as other metals.

  Further, in a hot chamber die casting machine for casting an aluminum-based molten metal, at least the components constituting the injection mechanism for injecting the aluminum-based molten metal are 50% to 60% by weight of nickel and 3% by weight of molybdenum. -20%, chromium is 14 to 18% by weight, iron is 0 to 5% by weight, and the rest is made of an aluminum-based corrosion resistant alloy metal with other metals.

In the component constituting the injection mechanism, an oxide paint is adhered to at least the surface of the component in contact with the molten aluminum;
In the component constituting the injection mechanism, an oxide film generated by an oxidation reaction by heat treatment is formed on at least the surface of the component in contact with the aluminum-based molten metal;
An inert gas having a specific gravity greater than that of air is present in the space between the plunger rod connected to the plunger above the plunger in the tubular space for the gooseneck plunger in the injection mechanism. Being filled to form an inert gas layer;
A lid member for sealing the inner space of the sleeve in the injection mechanism to prevent air from contacting the wall surface forming the inner space;
Is included.

  The gist of the casting method by the hot chamber die casting machine according to the present invention is the molten metal surface of the crucible for storing the aluminum molten metal when casting the hot chamber die casting machine for casting the aluminum molten metal by the hot chamber die casting machine of the present invention. The plunger constituting the injection mechanism and the inner wall surface of the sleeve with which the plunger is slidably contact are present at a lower position, and the plunger is reciprocated linearly so that it does not come out above the molten metal surface. Thus, the aluminum-based molten metal is injected into a mold.

  According to the hot chamber die casting machine of the present invention, at least the components constituting the injection mechanism for injecting the molten aluminum, the main component is 50% to 60% by weight of cobalt and 18 to 28% by weight of chromium. Since molybdenum is made of 4 to 17% by weight, nickel is 2 to 5% by weight, iron is 0 to 5%, and the rest is made of an aluminum-based corrosion-resistant alloy metal, and the remainder is eroded. Thus, it has become possible to cast an aluminum-based molten metal, which has been impossible in the past, with a hot chamber die casting machine. Thereby, the work efficiency of the casting of the aluminum-based alloy can be improved, and the manufacturing cost can be reduced.

  Further, at least the components constituting the injection mechanism for injecting the molten aluminum, the main components are nickel 50% to 60% by weight, molybdenum 3 to 20% by weight, and chromium 14 to 18 by weight. %, Iron is 0-5% by weight, and the rest is made of an aluminum-based corrosion-resistant alloy metal with other metals, so that, similarly to the above, the aluminum-based molten metal is prevented from being eroded. It is now possible to cast aluminum-based molten metal with a hot chamber die casting machine.

  In the component constituting the injection mechanism, the surface of the component is formed by adhering an oxide paint to at least the surface of the component in contact with the molten aluminum, or in the component constituting the injection mechanism. An oxide film formed by an oxidation reaction by heat treatment is formed on at least the surface that comes into contact with the aluminum-based molten metal, thereby preventing erosion of the injection mechanism by the aluminum-based molten metal and improving peelability and wettability. Thus, the durability of the hot chamber die casting machine can be further improved.

The space between the plunger and the plunger rod in the cylindrical space of the sleeve for the plunger of the gooseneck in the injection mechanism is filled with an inert gas having a specific gravity greater than that of air, and the inert gas layer In this way, the plunger can be protected from erosion caused by aluminum oxide produced by combining the molten aluminum with oxygen in the air.
In addition, a lid member that seals the inner wall of the sleeve in the injection mechanism so that air does not contact the wall surface that forms the inner space protects the wall surface that forms the inner space of the sleeve. Thus, corrosion of aluminum oxide is prevented, and durability can be improved.

  The casting method by the hot chamber die casting machine according to the present invention is based on the molten metal surface of the crucible storing the aluminum molten metal when casting the hot molten chamber die casting machine for casting the aluminum molten metal by the hot chamber die casting machine according to the present invention. In a lower position, the plunger constituting the injection mechanism and the inner wall surface of the sleeve in sliding contact with the plunger are reciprocated linearly so that the plunger does not come out above the molten metal surface. Since the aluminum-based molten metal is injected into the mold, the plunger does not touch the aluminum oxide and is reliably protected, and the reciprocating linear motion within the sleeve of the plunger is maintained smoothly. Is done.

  A hot chamber die casting machine 1 according to the present invention includes a crucible 3 for storing an aluminum-based molten metal 2, and a furnace body 4 that accommodates and supports the crucible 3, as shown in FIG. A heating device 5 such as a heater for heating the crucible 3 to keep the aluminum-based molten metal 2 at a predetermined temperature, a lid member 6 of the crucible 3, and between the lid member 6 and the upper surface 2 a of the aluminum-based molten metal 2. And an upper space inside the gooseneck are filled with an inert gas layer 7 filled with an inert gas such as argon gas or nitrogen gas, and an injection mechanism 8 supported by the lid member 6.

  The injection mechanism 8 includes a gooseneck 9, a sleeve 10 disposed in the aluminum-based molten metal 2, a nozzle 11 for injecting the aluminum-based molten metal 2 into a molding die, and aluminum filled in the internal space of the sleeve 10. It consists of a plunger 12 that presses and pushes in the molten metal 2 and a plunger rod 12a that drives the plunger.

  The driving device 23 for reciprocating linear movement of the plunger rod 12a in the vertical direction includes a hydraulic cylinder, a connecting rod, a coupling 23a for connection, and the like. In addition, as shown in FIG. 2, a molten metal temperature sensor 16, a melting tank 17, an argon gas sealing hole 18, a gooseneck temperature sensor 19, and the like are provided.

  In the hot chamber die casting machine 1 for casting an aluminum-based molten metal configured as described above, as a first embodiment, at least the parts constituting the injection mechanism 8 for injecting the aluminum-based molten metal are cobalt (Co) in a weight ratio. The main component is 50% to 60%, chromium (cr) is 18 to 28% by weight, molybdenum (Mo) is 4 to 17% by weight, iron (Fe) is 0 to 5%, and the rest is other It is formed of an aluminum-based corrosion-resistant alloy metal as a metal.

  As a second embodiment, at least the components constituting the injection mechanism 8 for injecting the molten aluminum 2 are mainly composed of nickel (Ni) in a weight ratio of 50% to 60%, and molybdenum (Mo). 3-20% by weight, 14-18% by weight of chromium (Cr), 0-5% of iron (Fe), and the other is formed of an aluminum-based corrosion-resistant alloy metal. is there. Examples of the other metal include tungsten (W), phosphorus (P), and niobium (Nb).

  The aluminum-based corrosion-resistant alloy metal is an alloy first created by the applicant of the present application, has good corrosion resistance with respect to the aluminum-based molten metal 2, and is very unlikely to be eroded. The aluminum-based corrosion-resistant alloy metal forms the gooseneck 9, the sleeve 10, the nozzle 11, the plunger 12, and the plunger rod 12a that constitute the injection mechanism 8. Further, as another embodiment, in addition to the case where these are formed only with the aluminum-based corrosion-resistant alloy metal, only the portion with which the aluminum-based molten metal 2 is in contact is formed with the aluminum-based corrosion-resistant alloy metal, and the outside thereof is other The low-cost composite metals are combined and the two types of composite metals are combined to form a gooseneck 9, a sleeve 10, a nozzle 11, a plunger 12, and a plunger rod 12a. You may do it.

  The hardness of the aluminum-based corrosion resistant alloy metal according to the first embodiment has a Rockwell value of about 44 to 48 (HRc), and the hardness of the second embodiment has a Rockwell value of 33 (HRc).

  As another embodiment of the present invention, in the third embodiment, in the parts constituting the injection mechanism 8, at least the surface of the parts in contact with the aluminum-based molten metal 2 is oxidized, for example, K-1. A thing paint is made to adhere. Thereby, for example, the wall surface of the gooseneck 9 is protected by the oxide paint, and is not eroded by the aluminum-based molten metal 2 stored in the space. Moreover, the peelability and wettability of the aluminum-based molten metal 2 from the parts constituting the injection mechanism 8 are improved.

  In the fourth embodiment of the present invention, in the component constituting the injection mechanism 8, an oxide film generated by an oxidation reaction by heat treatment is formed on at least the surface of the component in contact with the aluminum-based molten metal. is there. Similar to the third embodiment, the surface of a part formed of an aluminum-based corrosion-resistant alloy metal is oxidized to prevent erosion due to the aluminum-based molten metal 2 in contact therewith. Moreover, the peelability and wettability of the aluminum-based molten metal 2 from the parts constituting the injection mechanism 8 are improved.

  In the fifth embodiment of the present invention, as shown in FIG. 1, the space 9a between the plunger 12 and the plunger rod 12a in the cylindrical space for the plunger of the gooseneck 9 in the injection mechanism 8 is provided. Is that the inert gas layer 7 is formed by being filled with an inert gas such as argon (Ar) gas or nitrogen gas having a specific gravity greater than that of air.

The molten aluminum-based molten metal 2 enters the space 10a of the sleeve 10, and this reacts with oxygen in the air to generate aluminum oxide (Al ₂ O ₃ ). The aluminum oxide reacts with the plunger 12 formed of an aluminum-based corrosion resistant alloy metal to form an intermetallic compound, and the intermetallic compound prevents smooth sliding of the plunger 12. Therefore, the generation of such aluminum oxide is prevented. An inert gas layer 7 is also formed in the upper space of the aluminum-based molten metal 2 in the crucible 3 so that no harmful aluminum oxide is generated in the aluminum-based corrosion-resistant alloy metal.

  In addition to the embodiment for forming the inert gas layer 7, for example, as shown in FIG. 1, the entire upper portion of the furnace body 4 is covered with a cover body 14, and only necessary members are placed outside the cover body 14. It is also possible to propose that the hole on the nozzle 11 side is sealed and the internal space 7a is evacuated by a vacuum pump (not shown). Thereby, the aluminum-based molten metal 2 does not come into contact with air, and aluminum oxide is not generated.

  In the sixth embodiment of the present invention, as shown in FIG. 2, in the hot chamber die casting machine 1, the internal space 10a of the injection sleeve 10 is sealed by fitting a lid member so that air does not enter. is there. By expelling the air in the internal space 10a of the sleeve 10 to the outside, the molten aluminum-based molten metal 2 and oxygen in the air in the sleeve 10 are prevented from causing a chemical reaction. An inner diameter protection lid 13 such as a core rod is prepared as the lid member. The inner diameter protection lid 13 is made of a material such as carbon, carbon, graphite, boron, or the like, or is formed of a heat-treated member by thermal spraying / coating or the like, and is stored in the cylindrical inner space 10a of the sleeve 10 exactly. This is a cylindrical lid member.

  By fitting the inner diameter protection lid 13 into the inner space 10a of the sleeve 10, the air in the inner space is expelled. The inner diameter protection lid 13 is fitted to the sleeve 10 until immediately before casting with the aluminum-based molten metal 2. A through-hole 13a is formed in the vertical direction of the center portion of the inner diameter protection lid 13, and when the crucible 3 is filled with the aluminum-based molten metal 2, the aluminum-based molten metal 2 moves from the top to the bottom of the through-hole 13a. And flows through the runner 15 to the vicinity of the upper mouth of the nozzle, and pushes out the air in the runner 15 to the outside.

  The inner diameter protection lid 13 is pulled upward and removed when the aluminum-based molten metal 2 is cast. Then, the aluminum-based molten metal 2 enters from the lateral hole 9b and fills the internal space 10a of the sleeve 10 from below.

  Thereafter, the plunger 12 and the plunger rod 12 a are set on the sleeve 10. Thus, the inner peripheral wall surface 10b of the sleeve 10 is protected by the inner diameter protection lid 13 until just before casting, and the aluminum-based molten metal 2 is filled in the internal space 10a without being exposed to air, so that it is not oxidized. Therefore, there is no erosion due to the aluminum oxide generated by the oxidation of the aluminum-based molten metal 2, so that the durability of the sleeve 10 is improved.

  The seventh embodiment of the present invention relates to a casting method of a hot chamber die casting machine for casting an aluminum based molten metal by the hot chamber die casting machine 1, and at the time of casting the aluminum based molten metal, as shown in FIG. The plunger 12 constituting the injection mechanism 8 and the sleeve inner peripheral wall surface 10b in sliding contact with the plunger 12 are present at a position lower than the molten metal surface 2a of the crucible 3 storing the aluminum-based molten metal 2. Then, the plunger 12 is reciprocated linearly so as not to come out above the molten metal surface 2a, and the aluminum-based molten metal 2 in the internal space 10a of the sleeve 10 is pushed out into the runner 15 at a high pressure. The aluminum-based molten metal 2 is injected into (see FIG. 1).

  According to this casting method, the plunger 12 and the inner peripheral wall surface 10b of the sleeve 10 are always buried in the aluminum-based molten metal 2 without coming into the air, and are eroded by aluminum oxide. Since fear is surely excluded and an important part of the injection mechanism 8 is protected, the durability of the hot chamber die casting machine 1 is improved.

It is sectional drawing which expands and shows the outline of the injection mechanism 8 of the hot chamber die-casting machine 1 which concerns on this invention. FIG. 2 is a cross-sectional view of the hot chamber die casting machine 1 according to the present invention in a state where an inner diameter protection lid 13 is fitted to a sleeve 10. It is sectional drawing (A) of the hot chamber die-casting machine 1a which concerns on a prior art example, and its partially expanded view (B).

Explanation of symbols

1,1a Hot chamber die casting machine,
2 Aluminum-based molten metal,
3 crucibles,
4 furnace body,
5 heaters,
6 Lid member,
7 inert gas layer, 7a internal space,
8 Injection mechanism,
9 Gooseneck, 9a Space,
9b Horizontal hole
10 sleeve, 10a internal space,
10b inner wall surface, 10c hole,
11 nozzles,
12 Plunger, 12a Plunger rod,
13 inner diameter protective cover, 13a through hole,
14 Cover body,
15 Yudo.

Claims (7)

In a hot chamber die casting machine for casting an aluminum-based molten metal, at least the components constituting the injection mechanism for injecting the aluminum-based molten metal are composed of 50% to 60% by weight of cobalt and 18 to 28 by weight of chromium. %, Molybdenum is 4 to 17% by weight, nickel is 2 to 5% by weight, iron is 0 to 5%, the rest is made of an aluminum-based corrosion-resistant alloy metal with other metals,
Hot chamber die casting machine characterized by In a hot chamber die casting machine for casting an aluminum-based molten metal, at least components constituting an injection mechanism for injecting the aluminum-based molten metal are composed of nickel as a main component in a weight ratio of 50% to 60% and molybdenum as a weight ratio of 3 to 20 %, Chromium is 14 to 18% by weight, iron is 0 to 5% by weight, and the rest is made of an aluminum-based corrosion resistant alloy metal with other metals,
Hot chamber die casting machine characterized by In the parts constituting the injection mechanism, at least the surface of the parts in contact with the molten aluminum is adhered to the oxide paint,
The hot chamber die-casting machine according to claim 1 or 2, wherein In the component constituting the injection mechanism, an oxide film formed by an oxidation reaction by heat treatment is formed on at least the surface of the component in contact with the aluminum-based molten metal,
The hot chamber die-casting machine according to claim 1 or 2, wherein An inert gas having a specific gravity larger than air is present in the space between the plunger and the plunger rod connected to the plunger in the cylindrical space of the plunger sleeve of the gooseneck in the injection mechanism. An inert gas layer is formed by filling,
A hot chamber die casting machine according to any one of claims 1 to 4. A lid member that is sealed so that air does not contact the wall surface that forms the internal space is fitted in the internal space of the sleeve in the injection mechanism,
The hot chamber die casting machine according to any one of claims 1 to 5. An injection mechanism is provided at a position lower than a molten metal surface of a crucible for storing the aluminum-based molten metal at the time of casting of the hot chamber die-casting machine for casting the aluminum-based molten metal by the hot chamber die-casting machine according to claim 1. The aluminum-based molten metal is moved to the mold by reciprocating linearly moving the plunger so that the plunger does not come out above the molten-metal surface so that the plunger and the inner wall surface of the sleeve with which the plunger slides are present. That it was made to fire,
A casting method using a hot chamber die casting machine.

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