JP3156922B2 - Method and apparatus for semi-solid metal injection molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for semi-solid metal injection molding, and more particularly to an injection molding method and apparatus suitable for increasing the production amount by generating fine cells and using a screw type injection mechanism. It is about.

[0002]

2. Description of the Related Art It is well known that steelmaking methods have been improved by utilizing semi-solid material molding technology, and in the early 1970's this technology was developed by Massachusetts Institute of Technology (MI).
Since the basic theory was published by T), the technology development and manufacturing process in this regard have been gradually completed. Thereby, while maintaining the production speed of the conventional die casting method, the dimensional accuracy is improved, and at the same time, the blowholes (BLOWHOLE) in the casting are reduced to enhance the mechanical properties of the product. Reached the purpose of meeting. Conventional technology is disclosed in, for example, U.S. Pat. No. 3,902,544, which was acquired by the Massachusetts Institute of Technology. The molten metal liquid was put into a stirring tube and continuously stirred while being cooled. A semi-solid state is formed by the shearing action, which is cooled to form an ingot (CASTIN).
G INGOT). However, when forming such an ingot into a casting, it is again cut into smaller materials, heated and then sent to a die casting machine to form. The ingot of such a manufacturing method is in a semi-solid state, and becomes a solid state in a mold. This is relatively similar to traditional steelmaking,
"Sixophorging method" (THIXOFORGIN
G). However, such a process is clearly a complicated method. In addition, Dow Chemical Company (THE D
The technique described in US Patent No. 5,040,589 to OW CHEMICAL COMPANY is that a metal granule is heated and sheared by an injection molding machine until a part thereof is melted, turned into a semi-solid state, and then extruded with a screw. Mold. Also, the Kernel Research Foundation (CORN)
ELL RESEARCH FOUNDATION, I
NC. No. 5,501,266) melts the metal by a specially designed injection molding machine, cools to a semi-solid state by directly using a tube and a screw for charging the material, shears the material, and then uses a screw. Extrude and mold. The stirring of the metal material is performed by the screw stirring described above (Japanese Patent Publication Nos. 1-170565, 1-178345, 1-1).
No. 92447), stirring using blades (for example, US Pat. No. 4,116,423), and electromagnetic stirring (ELE).
CTRO-MAGNETIC STIRRING (for example, US Pat. Nos. 5,178,204 and 5,21)
9,018). In the screw-based technique described above, the molten metal material and the semi-solid metal material move in one and the same place. However, the cooling of the molten metal material to the semi-solid state needs to be performed promptly, and the metering injection of the semi-solid metal requires a stable temperature environment. The temperature control conditions of the two are completely different, and heat is transmitted in the same one place, making temperature control difficult, so it is not suitable for mass production.

[0003]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a method for heating a metal material in a first step and rapidly mixing a semi-solid metal while rapidly cooling in a second step. Produces semi-solid serous material, including fine cells. As a third step, under a stable temperature controlled by temperature control, while the shear stirring is continued by a screw, fine cells of semi-solid serous liquid are evenly distributed to the mold, measured and injected into a mold, and solidified in the mold. The above-mentioned temperature control in the second stage and the third stage are performed separately, and not only fine cells can be easily obtained in the second stage, but also the temperature can be controlled without affecting each other. It is suitable for the production of large castings because it produces a large amount of semi-solid serous material. In addition, the semi-solid serum generator used for producing the semi-solid serum metal in the second step of the present invention does not receive high pressure during injection by the die casting method. Therefore, the wall of the container containing the molten metal can be made as thin as possible, which also contributes to the efficiency of the rapid cooling in the second stage.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a method and apparatus for injection molding a semi-solid metal. In a first step, a metal material is heated, and in a second step, a semi-solid metal is rapidly cooled while being rapidly cooled. A semi-solid serous material having fine cells is produced by a manufacturing method in which agitation is performed. As a third step, under a stable temperature controlled by a temperature control, while the shearing and stirring are continued by the screw, the fine cells of the semi-solid serum are evenly distributed to the mold while being measured and injected, and solidified in the mold. Since the above-mentioned temperature control in the second stage and the third stage are performed separately, not only it is easy to obtain fine cells in the second stage, but also it is possible to control the temperature without affecting each other. In addition, since semi-solid serum material can be produced in large quantities, it is suitable for the production and production of large castings.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 2, a semi-solid metal injection molding apparatus according to the present invention is mainly composed of a metal producer 1 for producing a high-quality metal solution using a protective gas, and a metal producer for supplying a solution. 1 and connected rapidly to the heated liquid metal material while rapidly cooling the liquid metal material to maintain the temperature of the metal material within the range of the temperature at which solidification starts and the temperature at which solidification ends. A semi-solid serous producer 2 for producing semi-solid metal, and connected to a semi-solid serous outlet 201 of the semi-solid serous producer 2 to provide a temperature control function, maintain a semi-solid temperature, and measure Includes an injector 3 that is injected and solidified in a mold 4.

The technology that is the key of the present invention is the second technology described above.
By separately controlling the temperature of the semi-solid serum generator 2 in the stage and the temperature of the injector 3 in the third stage, the second stage and the third stage are controlled.
Ensure that the temperature control in the stages does not affect each other. In addition, each is easily controlled, and a semi-solid state including fine cells is obtained, and then the semi-solid state is maintained by the third-stage injector 3. After metering with the injector 3, it is poured into the mold 4 to form a casting with the properties of a semi-solid material. This integrated manufacturing process and equipment is suitable not only for producing castings with excellent quality and performance, but also for mass production of semi-solid materials, so that it is suitable for speedy mass production.

A method of implementing the present invention, as shown in FIG.
The following steps are included. 1. Make hot liquid metal. 2. Cutting the hot liquid metal by shearing force, cooling rapidly during the cutting process to maintain the temperature of the metal material within the range of the temperature at which solidification starts and the temperature at which solidification ends, to form a semi-solid serum. Send out. 3. While maintaining the temperature within the range of the temperature at which coagulation starts and the temperature at which coagulation ends in the device for containing semi-solid serum as described above, the dendrite structure (DENDRICIC Stru.
CTURE) by shearing while maintaining a high quality semi-solid serum. 4. The semi-solid solution is injected into a mold using an injector to form a semi-solid casting material.

FIGS. 2 and 3 show an embodiment completed on the basis of the characteristics of the above-mentioned technology. As shown in FIG. 2, the apparatus according to the present invention mainly comprises a method in which a molten metal material is heated to a liquid. A metal producer 1 which forms a shape and delivers hot liquid metal, a protective gas supply 5 which prevents and protects the heated liquid metal from being oxidized, and which is connected to the metal producer 1 and delivered as described above. The semi-solid serous generator 2 which receives the liquid metal, rapidly cools and simultaneously produces the semi-solid metal in a fine cell under the condition of high-speed stirring, to the semi-solid serous outlet 201 of the semi-solid serous producer 2 The semi-solid injector 3 is connected and provided with a temperature control function, maintains a constant temperature for the above-mentioned semi-solid state, and performs opening and closing operations by a semi-solid injector 3 for injecting an appropriate amount and a mold clamp 6. Mold 4 for producing a casting by compressing the semi-solid state injected from Constructed.

The protective gas supply 5 supplies a gas such as nitrogen, argon or sulfur hexafluoride to fill the metal producer 1. The semi-solid serum production device 2 is the metal production device 1 described above.
A liquid inlet 200 connected to the liquid metal outlet 10 of
It is desirable that the hollow tube 21 to be sent out to the semi-solid serum outlet 201 has an inclined system in which the liquid inlet 200 is higher than the semi-solid serum outlet 201 so that the heated liquid metal flows to the injector 3 naturally. The temperature control device for controlling the temperature of the tube 21 includes a heating part 25 wound around the tube 21 to quickly turn the hot liquid metal into a semi-solid serous metal.
It is composed of a cooling part 23 and an insulating warmer 24.
Actually, the heating part 25 is a heating wire and an induction heater, and the cooling part 23 is a cooler through which a cooling medium flows, and the medium has an effect of rapidly cooling with water, air, a liquid transmitting heat, or the like. Reach. Cooling must be performed at a temperature at which the metal material does not solidify and maintains fluidity.
If the cooling temperature is too low, the temperature is raised using the heating part 25 to return it to an appropriate range. The above-mentioned semi-solid serum production device 2 includes a stirrer for rapidly stirring semi-solid metal in a process of rapidly cooling liquid metal. The stirring device is an electromagnetic stirring
Using a stirrer 22, a dendrite structure (DENDRICIC Struct) is formed by shearing force when the metal solidifies.
URE) to produce fine semi-solid metal.

The injector 3 described above has a hollow tube (30) for temporarily storing semi-solid serum, the hollow tube 30 being connected to an inlet 300 connected to the semi-solid serum outlet 201 of the semi-solid serum producer 2.
And the other end of the hollow tube 30 has a spout 31 and is used to inject the semi-solid serum into the mold 4. The end of the spout 31 is preferably tapered upwards, which prevents the semi-solid serum from dripping or flowing out when the spout 31 is not connected to the mold 4.
The temperature control device of the hollow tube 30 and the spout 31 is used to maintain the metal in a semi-solid state before injecting the semi-solid serum into the mold 4. This temperature control device is the same as the temperature control device of the semi-solid serum production device 2 described above, and the hollow tube 30 and the ejection port 3 are provided.
The heating part 32, 32 ′, the cooling part 33, 33 ′ and the insulation warmer 34 surround the outside of the device 1. Actually, the heating parts 32 and 32 'are heating wires and induction heaters, and the cooling parts 33 and 33' are coolers through which a cooling medium flows. The medium includes water, air, and a liquid for transmitting heat. It is used to achieve rapid cooling. Since main purpose of the temperature control in the ejector 3 of the third stage, such to maintain a semi-solid serum conditions, the accuracy of temperature control is very important. The cooling parts 33, 33 ′ prevent the temperature from becoming too high due to heating, and an injection device for injecting a semi-solid serous state into the mold 4 is provided inside the injector 3. This injection device uses a screw 35
Using the backflow prevention valve 36, the injection amount and pressure molding of the metal in the semi-solid serous state are performed by moving and pressurizing the screw 35. In the third stage, the turning of the screw 35 is performed.
Stirring is performed on the semi-solid serum by movement. This integrated manufacturing process and equipment not only allows for the production of casts of excellent quality and performance, but also allows the semi-solid serous material to be produced by the semi-solid serous generator 2.
In order to achieve the purpose of material weighing and injection by the injector 3, it is suitable for the production of large castings and speedy mass production.

In the above-described example, the open / close valve 26 is provided between the semi-solid serum outlet 201 of the semi-solid serum producer 2 and the inlet 300 of the injector 3. Thereby, the temperature of the semi-solid serum production device 2 and the temperature of the injection device 3 do not influence each other, and they are designed so that the temperature can be adjusted individually and easily and accurately. Further, since the semi-solid serum production device 2 does not receive the high pressure at the time of injection of the semi-solid serum, the thickness of the tube 21 can be reduced as much as possible, so that the cooling can be rapidly performed.

Since the structure of the mold 4 and the mold clamp 6 is similar to the conventional casting equipment, the detailed description of the structure is omitted here. The mold clamp 6 is also installed at an angle in accordance with the inclination of the jet port 31 described above, and the drive unit 61 moves the mold clamp 6 to perform connection and disconnection operations with the jet port 31.

[0013]

In summary, the method and apparatus for semi-solid metal injection molding of the present invention are excellent in the following points. 1. The rapid cooling of the second stage semi-solid serum producer and the temperature control for maintaining the temperature of the third stage injector can be controlled without affecting each other. 2. A semi-solid serum containing fine cells is formed during the second stage of rapid cooling. Stirring in a stable temperature environment in the third stage can produce a high quality semi-solid serum. 3. Since the equipment in the second stage does not affect the injector, a large amount of semi-solid serum can be produced during the molding process such as pressurized cooling and jetting off, and can be metered in the third stage. . This allows for the production of large castings. To make it easier to understand the difference between the present invention and the prior art,
Compare each other below.

1. In the prior art, the work of cooling, shearing and injecting the semi-solid serum was performed in the same place, but in the present invention, the raw material was first produced speedily, and then continuously in another place where the temperature was stable by a screw. Injection is performed while cutting in a regular manner. 2. In the prior art, the mold clamping and the injector were installed vertically and the ejection port turned downward, and the injection parts moved up and down to contact and separate the mold and the ejection port. The mold clamp is inclined and the injector is horizontal, and the mold clamp moves back and forth to contact and separate the mold and the spout. 3. In the conventional technology, since the temperature control is performed in the same place, it is difficult to accurately control the temperature due to mutual temperature interference.However, in the present invention, since the semi-solid serum production and the injector are separated, they are affected by each other. Precise temperature control can be performed without giving 4. In the prior art, the cooling and cutting are performed simultaneously in the same place, so that the microstructure is coarse and large, and the production rate of semi-solid serum is low. In the present invention, the semi-solid serum cools quickly, and the continuous cutting of the injector can produce a stable semi-solid serum containing fine cells quickly. 5. In the prior art, the material was easily leaked from the mold clamp and the spout, and there was a problem of interruption of the manufacturing process and safety. However, in the present invention, the mold clamp is inclined to prevent the material from leaking. 6. Although it was difficult to mass-produce a large casting with the structure of a conventional machine, the present invention achieves mass automatic production, simplification of the manufacturing process, and stability of quality by adopting a two-stage structure.

[Brief description of the drawings]

FIG. 1 is a flowchart of a method for semi-solid metal injection molding of the present invention.

FIG. 2 is a partial sectional structural view of the semi-solid metal injection molding apparatus of the present invention.

FIG. 3 is a partially enlarged view of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal production machine 2 Semi-solid serum production machine 3 Injector 4 Mold 5 Protection gas supply device 6 Mold clamping 10 Hot liquid metal outlet 21 Tube 22 Electromagnetic stirrer 23 Cooling parts 24 Insulation warmer 25 Heating parts 26 Opening / closing valve 30 Medium Empty tube 31 Spouting port 32 Heating part 33 Cooling part 34 Insulation warmer 35 Screw 36 Backflow prevention valve 61 Driver 200 Liquid inlet 201 Semi-solid serous liquid outlet 300 Inlet

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ken Yone Ne, No. 137 Jinlin Road, Zhudong Town, Hsinchu County Taiwan References JP-A-7-51827 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B22D 17/00 B22D 17/20 B22D 17/30

Claims (6)

(57) [Claims] Producing a hot liquid metal and protecting the heated liquid metal with a protective gas; cutting the liquid metal by shearing force, rapidly cooling the liquid metal material during the cutting; Maintaining the temperature of the metallic material within the range of the temperature at which solidification starts and the temperature at which solidification ends, forming and sending a semi-solid serum; storing the semi-solid serum in a container and maintaining the temperature of the semi-solid serum; And a step of injecting the semi-solid serum into a mold by an injector to form a semi-solid casting. 2. A hot liquid metal is placed in a hollow tube and rapidly cooled.
The method for injection molding of a semi-solid metal according to claim 1, wherein shearing is performed using an electromagnetic stirring device to form a semi-solid serum. 3. A metal raw material for producing a liquid metal by heating a metal material.
The production equipment (1) cuts the liquid metal by high-speed stirring means.
The liquid metal material is cooled rapidly during the cutting process of the metal material.
The temperature of the mixture is set between the temperature at which coagulation starts and the temperature at which coagulation ends.
Semi-solid serous generator for producing semi-solid serous liquids within the range
(2) a screw-type injector (3) composed of an injector (3) and a mold (4), wherein a metal producer (1) is connected to a semi-solid serous fluid producer (2) and has a temperature adjusting function; 3) is connected to the semi-solid serum outlet (201) of the semi-solid serum producer (2), and the mold (4) receives the semi-solid serum from the injector (3) and solidifies to produce a casting. Semi-solid metal injection molding equipment. 4. A semi-solid serous producer (2) having a hollow tube connected to a liquid inlet (200) and a semi-solid serous outlet (201) of a metal producer (1). ) rapidly lowering the temperature of the hot liquid metal by using a temperature control mechanism for controlling the temperature of the provided tube (21), the collector
The semi-solid metal injection molding apparatus according to claim 3, wherein the liquid metal is stirred at a high speed by a magnetic stirrer . 5. A temperature control mechanism comprising a heating part (25) wound around a pipe (21), a cooling part (23) and an insulating warmer (24).
5) A heating wire or an induction heater, wherein the cooling part (23) is water for cooling, a gas, a liquid for transferring heat, or other fluid material having the same property. 5. The semi-solid metal injection molding apparatus according to claim 1. 6. An injector (3) for temporarily storing semi-solid serum.
Hollow tube (30) and controlling the temperature of the hollow tube
The hollow tube (30) has one end at one end.
It has a spout (31) that is slightly inclined upward, and is hollow
Temperature control mechanism to control the temperature of the tube is semi-solid serum
The semi-solid metal injection molding apparatus according to claim 3, wherein the apparatus has the same structure as the temperature control mechanism of the production unit (2) .