KR100432983B1 - Method for manufacturing of metallic materials in coexisting state of solid and liquid - Google Patents

Abstract

The present invention provides an applying step of applying an electromagnetic field to the container, an injection step of injecting the molten metal material into the container while the electromagnetic field is applied to the container, and after the injection of the metal material is completed, There is provided a method for producing a metal material in a solid-liquid coexistence state, including a terminating step of terminating application of an electromagnetic field to a container, and a cooling step of cooling the metal material in the container. According to the method of the present invention, in the process of cooling the metal material in the container, since the temperature is reduced uniformly from the wall surface of the container to the center without generating latent heat due to the initial solidification layer formation, the molten metal material The metal material in the vessel is rapidly cooled below the liquidus temperature within a short time of about 1 to 10 seconds after the injection of a large number of crystal nuclei to be produced uniformly over the entire region, thereby producing a metal material having a fine and uniform structure. can do.

Description

Method for manufacturing of metallic materials in coexisting state of solid and liquid}

The present invention relates to a method for producing a metal material in a solid-liquid coexistence state prepared by injecting a molten metal material under an electromagnetic field into a container and cooling the same.

The reaction solid or semi-melt processing is a composite processing method in which casting and forging are mixed, and can be classified into two types, reaction casting and thixoforming. The reaction molding method is a processing method of directly forming and processing a slurry produced in a reaction state into a final product. The semi-melting molding method manufactures a billet in a reaction state, and then reheats the billet in a semi-melt state. Refers to the processing method for producing the final product by forging or die casting.

The metal slurry for the reaction solid or semi-melt molding can be deformed by a small force due to its thixotropic property in the state where liquid and spherical crystal grains are mixed at an appropriate ratio at the temperature of the reaction solid region, and fluidity is excellent. It means a metal material in the state of easy molding processing, such as liquid. Since the billet can recover the semi-melt state of a metal slurry form by reheating, it is very useful as a reaction material or a metal material for semi-melt molding.

The reaction solid or semi-molten molding method using a metal slurry or billet has various advantages over the case of using a liquid metal alloy of the same composition. For example, the metal slurry has fluidity at a temperature lower than the temperature required to completely melt such liquid metal alloys, so that the temperature at which the die is exposed can be lowered, thus resulting in longer die life. In addition, when the metal slurry is extruded, there is no turbulence and less air is mixed in the casting process, thereby preventing the generation of pores in the final product. Therefore, heat treatment is possible, thereby greatly improving mechanical properties. In addition, solidification shrinkage is small, workability and corrosion resistance are improved, and the weight of the product can be reduced. Therefore, it can be used as a new material of the electric and electronic information communication equipment in the automobile and aircraft industries.

The conventional method for producing a high-alloy alloy is to destroy the dendrite crystal structure already formed by stirring a metal material at a temperature below the liquidus line to make spherical particles suitable for reaction solidification. Mechanical stirring, electromagnetic stirring, gas bubbling, low frequency, high frequency or electromagnetic vibration, or agitation by electric shock have been used.

For example, US Pat. No. 3,948,650 describes a process for preparing a liquid-solid mixture, in which the alloy is heated to a temperature at which most of the alloy is in the liquid phase and then hardened to the formed metal material. Cool with stirring. Cooling is continued while stirring until the solid percentage of the metal material reaches 40% or more and 65% or less, thereby preventing the formation of dendritic crystal structures or removing or reducing the dendrite structures already formed on the primary solid particles. To prepare a solid-liquid mixture.

U.S. Patent No. 4,465,118 discloses a method for producing a semi-solid alloy slurry, in which a moving magnetic field is provided over the entire range of solidification zones in a container containing a metallic material. The metal material is electromagnetically mixed by a non-zero magnetic field. In this method, the magnetic field causes the dendritic crystal structure formed in the solidified region to shear at a predetermined shear rate.

In addition, US Pat. No. 4,694,881 describes a method of making thixotropic materials. In this method, the alloy is heated such that all metal components in the alloy are in the liquid state, and then the resulting liquid metal is cooled to a temperature between the liquidus and solidus lines. Next, a method of producing a thixotropic material by breaking a dendritic crystal structure formed from a metal material to be cooled by applying a shearing force is described.

Japanese Patent Application Laid-Open No. 11-33692 describes a method for producing a metal slurry for reaction solid casting. In this method, molten metal is injected into the vessel near the liquidus temperature or up to 50 ° C above the liquidus, and then at least a portion of the metal material becomes below the liquidus temperature during the cooling of the molten metal, ie the liquidus for the first time. At the time when the temperature passes, the motion is applied to the metal material by, for example, ultrasonic vibration or the like. Finally, by cooling the metal material gradually, a metal slurry for reaction solid casting having a metal structure in the form of granular crystals is produced.

That is, by applying a proper motion in the vicinity of the liquid line to the metal material, the dendritic crystal structure that is thought to be formed in each of the initial crystal nuclei formed initially, so that the particles exist independently without interaction between the initial crystal nuclei. Cool slowly at to form granular crystals. Also in this method, force such as ultrasonic vibration is used to destroy the dendritic crystal structure initially formed upon cooling. In addition, when the pouring temperature is higher than the liquidus temperature, it is difficult to obtain a crystalline form of granules, and it is also difficult to rapidly cool the molten metal. In addition, the structure of the surface portion and the central portion becomes uneven.

In addition, Japanese Patent Application Laid-open No. Hei 10-128516 discloses a method for forming a semi-molten metal. In this method, molten metal is injected into the container, and then the vibration bar is deposited in the metal material and vibrated in direct contact with the metal material to give vibration to the metal material. Specifically, the molten metal is first injected into the container, and then the vibration bar is deposited in the metal material to transmit the vibration force to the metal material. After forming an alloy in a solid-liquid coexisting state with crystal nuclei in the temperature range therebetween, fine crystal nuclei are grown in the alloy by maintaining the metal material in a vessel for 30 seconds to 60 minutes while cooling the metal material in a container to a forming temperature showing a predetermined liquidity. To obtain a semi-fused metal. The size of the crystal nucleus produced by this method is about 100 mu m, the process time is considerably long, and it is difficult to apply to a container of a predetermined size or more.

U. S. Patent No. 6,432, 160B1 describes a method of making a semi-molten metal slurry. In this method, a semi-molten metal slurry is produced by precisely controlling cooling and stirring simultaneously. Specifically, after injecting the metal material into the mixing vessel, a stator assembly installed around the mixing vessel is operated to generate sufficient magnetomotive force to rapidly stir the metal material in the vessel. The temperature of the metal material is rapidly lowered by using a thermal jacket installed around the mixing vessel and precisely controlling the temperature of the container and the metal material. When the metal material is cooled, the metal material is continuously agitated and adjusted in such a way as to provide rapid agitation when the solid fraction is low and provide increased electromotive force as the solid phase is increased.

As described above, most of the prior art uses a method of pulverizing the dendritic crystal form already formed in the cooling process by using the shear force to form a granular metal structure. Therefore, when at least a part of the molten metal is lowered below the liquidus line, it is difficult to avoid various problems such as decreasing the cooling rate and increasing the manufacturing time due to latent heat generation due to the formation of the initial solidification layer. . In addition, if the injection temperature of the metal material into the container is not controlled, it is difficult to prevent the formation of the dendritic crystal structure of the initial solidification layer near the wall due to the temperature difference between the wall part and the center of the container. You have to adjust it.

The present invention has been proposed to solve the above problems of the prior art, while obtaining finer spherical particles compared to the conventional method while improving energy efficiency, reducing manufacturing costs, improving mechanical properties, simplifying the casting process and shortening the manufacturing time. An object of the present invention is to provide a method of manufacturing a metal material in a solid-liquid coexistence state which can realize the advantages of the same.

1A is a process diagram of a method of manufacturing a metal material in a solid-liquid coexistence state according to an embodiment of the present invention, and FIG. 1B is a photograph showing a structure of an alloy manufactured according to the process of FIG. 1A,

2 to 5 are photographs showing the structure of the alloy produced by varying the container injection temperature of the metal material in the method of producing a metal material in a solid-liquid coexistence state according to the present invention,

6 to 9 are photographs showing the structure of the alloy prepared by varying the cooling rate in the step of cooling the metal material after the completion of electromagnetic field stirring in the method of manufacturing a metal material in a solid-liquid coexistence state according to the present invention ego,

10 to 12 are photographs showing the structure of the alloy produced in accordance with the change of the end point of applying the electromagnetic field in the method of manufacturing a metal material in a solid-liquid coexistence state according to the present invention,

13 is a photograph showing a structure of an alloy produced by applying an electromagnetic field simultaneously with injection of a metal material into a container in the method for producing a metal material in a solid-liquid coexistence state according to the present invention;

14 is a photograph showing a structure of an alloy prepared by applying an electromagnetic field while injecting a metal material into a container in the method of manufacturing a metal material in a solid-liquid coexistence state according to the present invention.

15a to 15b are photographs showing the structure of the surface portion and the central portion of the alloy prepared according to another embodiment of the present invention,

16a to 16b are photographs showing the structure of the surface portion and the central portion of the alloy prepared according to another embodiment of the present invention,

17a to 17b are photographs showing the structure of the surface portion and the central portion of the alloy prepared according to the conventional reaction solidification method,

18A to 18B are photographs showing the structure of the surface portion and the central portion of the alloy prepared by another conventional reaction solidification method.

In order to achieve the above object, according to the present invention, an applying step of applying an electromagnetic field to the container; injecting the molten state of the metal material into the container while the electromagnetic field is applied to the container; Terminating the application of the electromagnetic field to the container after the injection of the material is complete; And a cooling step of cooling the metal material in the container. The present invention also provides an application method of applying an electromagnetic field to a container. An injection step of injecting a molten metal material into the container; an end step of terminating application of an electromagnetic field to the container after the injection of the metal material is completed; And a cooling step of cooling the metal material in the container.

In addition, the present invention provides a metal material in a solid-liquid coexistence state in which the distribution of crystal nucleus particles is uniform and the grain structure is spherical as a metal material produced by the above method.

According to the method for producing the reaction solid or semi-melt forming metal material of the present invention, the temperature of the metal material in the container is uniform. That is, since there is almost no temperature difference between the center and the wall portion of the container containing the metal material and the upper and lower parts, latent heat due to initial solidification in any specific region does not occur, so that the metal material can be rapidly cooled in a short time. Therefore, the density of crystal nucleation of the metal material is significantly increased, thereby making it possible to realize miniaturization of the spherical particles.

Hereinafter, the present invention will be described in more detail.

In the present invention, before the injection of the metal material is completed, that is, before injecting the metal material into the container, or by injecting the metal material into the container and applying an electromagnetic field to the container to produce a metal material for reaction or semi-melt molding do. Ultrasonic waves or the like may be used instead of the electromagnetic field. The metal that can be applied to the method of the present invention can be used as long as it can be used for reaction solid or semi-melt molding, and in the group consisting of aluminum, magnesium, copper, zinc, iron and alloys thereof It is preferred to be selected. The alloy may comprise any of a variety of metals, depending on the properties required in the final molded article.

At the time of injecting the metal material into the container, the temperature of the metal material is preferably maintained at a temperature between the liquidus temperature and the liquidus + 100 ° C (melt superheat, melt superheat = 0 ° C ~ 100 ° C). According to the method of the present invention, since the entire inside of the container containing the metal material is cooled uniformly, it is not necessary to cool the liquidus temperature near the liquidus temperature before injecting the metal material into the container and maintain the temperature of about 100 ° C higher than the liquidus temperature. It is okay.

On the other hand, in the conventional method, since the electromagnetic field is applied to the container when the molten metal is injected into the container and a part of the molten metal becomes below the liquidus line, the initial solidification layer is formed on the wall of the container, and the latent heat of solidification is generated. Since the latent heat is about 400 times the specific heat, it takes much time for the temperature of the metal material of the entire container to drop. Therefore, in such a conventional method, it is common to cool the temperature of the metal material to a temperature of about 50 ° C. above the liquidus level or inject the liquid into the vessel.

In the method of the present invention, as the electromagnetic field is applied before the injection of the metal material into the container is completed, there is little temperature difference between the wall portion and the central part, the upper part and the lower part of the container in which the metal material is injected. Therefore, the initial solidification does not occur in the vicinity of the vessel wall generated in the prior art, the entire metal material in the vessel can be rapidly cooled uniformly below the liquidus temperature to generate a large number of crystal nuclei at the same time. In the present invention, the reason why the temperature difference does not occur throughout the container is because the electromagnetic field is already applied to the container before the injection of the metal material into the container is completed. This is because the material is well stirred and heat transfer occurs quickly in the metal material, so that formation of an initial solidification layer on the inner wall of the container is suppressed. In addition, convective heat transfer between the well-stirred metal material and the low temperature inner wall of the container is increased to rapidly cool the temperature of the entire metal material. That is, in the present invention, the injected metal material is dispersed into dispersed particles by electromagnetic field stirring at the same time as the injection, and the dispersed particles are evenly distributed in the container as crystal nuclei, so that a temperature difference does not occur throughout the container. On the other hand, according to the related arts, the injected metal material is brought into contact with the inner wall of the low temperature container to grow dendritic crystals in the initial solidification layer by rapid convective heat transfer.

The principles of the present invention may be explained in terms of latent clotting. According to the method of the present invention, since the initial solidification of the metal material on the wall surface of the container does not occur, and there is no latent heat of solidification, the cooling of the metal material is only the specific heat of the metal material (only about 1/400 of the latent heat of solidification). Only the release of calories equivalent to) is possible. Therefore, in the prior art, without the formation of dendritic crystals, which are the initial solidification layers commonly occurring in the wall portion of the container, the metal material in the container exhibits a uniform and rapid temperature drop across the center from the wall surface of the container. The time required to lower the temperature is only a short time of about 1 to 10 seconds after injecting the molten metal material. Accordingly, a large number of crystal nuclei are uniformly generated throughout the metal material in the container, and the distance between the crystal nuclei becomes very short due to an increase in the density of nuclei formation, so that dendritic crystals do not form and grow independently to form spherical particles. do.

The application of the electromagnetic field is terminated when the temperature of the metal material in the vessel reaches near the liquidus line. That is, it ends when the crystal nucleus is generated in the metal material. However, the end point of applying the electromagnetic field may be any time between the end point of crystal nucleation of the metal material and the end point of cooling. The end point of the electromagnetic field application is preferably a time when the solid phase rate of the metal material is 0.001 to 0.7, more preferably 0.001 to 0.4, and most preferably 0.001 to 0.1 in terms of energy efficiency.

After the application of the electromagnetic field to the container is finished, the metal material is cooled until a predetermined solid phase ratio, preferably 0.1 to 0.7, is reached.

In the cooling step, the cooling rate of the metal material is preferably 0.2 ° C./sec to 5.0 ° C./sec, and the cooling rate may be 0.2 ° C./sec to 2.0 ° C./sec in terms of the distribution of crystal nuclei and fine particles. have.

According to the method of the present invention, the time required from the time of injecting the molten metal material into the container to the time of forming the metal material in the form of a metal slurry with a solid phase of 0.1 to 0.7 is only 30 seconds to 60 seconds. The metal slurry can be made into billets by rapid cooling.

The metal material in the form of a metal slurry or billet may be subjected to secondary molding steps such as die casting, squeeze casting, forging, and press working. Metallic materials produced in the form of billets can be cut into suitable lengths and made into slugs, and for secondary molding the slugs are recovered to semi-melt state by reheating.

The metal particles contained in the reaction solid or semi-melt forming metal material produced by the method of the present invention are fine spherical particles having an average particle diameter of 10 to 60 µm, and their distribution is uniform.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

Example 1

In this embodiment, an A356 alloy, which is an aluminum alloy, is used as the alloying material of the metal material. 500 g of A356 alloy was heated in an electric furnace (10 kW) using a graphite crucible and heated at a temperature of about 750 ° C. for 1 hour to dissolve the molten metal material. temperature) was measured so that the temperature of the metal material was below 100 ° C higher than the liquidus temperature of the metal material (about 615 ° C for the A356 alloy).

1A is a working flowchart according to the present embodiment.

In applying the electromagnetic field to the vessel, the voltage, frequency and intensity of the electromagnetic stirrer (EMS) were fixed at 250V, 60Hz and 500Gauss, respectively. Prior to injecting the metal material into the container, while supplying power to the EMS to operate the EMS, the metal material is introduced into the container when the temperature of the metal material reaches 650 ° C. (Tp: pouring temperature in FIG. 1A). Injected.

After injecting the metal material in the molten state into the container while applying electromagnetic stirring to the container in advance, the EMS operation is stopped when the temperature of the metal material reaches the liquidus line (point “a” in FIG. 1A). I was. That is, the EMS was operated only in section "p" of FIG. 1A. After the EMS operation was stopped, the metal material was cooled by cooling the metal material at a cooling rate of 1 ° C./sec to a temperature at which the solid phase ratio became 0.6 (point “b” in FIG. 1A, and the temperature at this time was about 586 ° C.). . Approximately 40 seconds were required from the time of injecting the molten metal material into the container until the solid phase rate of 0.6 was reached.

Subsequently, a secondary molding process is performed, that is, after the point “b” in FIG. 1A, a secondary molding step such as die casting, squeeze casting, forging, or press working is performed. Go through.

In order to observe the metal structure of the metal material prepared according to the method of Example 1, the specimen was made by the following method. First, the metal slurry was quenched to prepare a billet. Cut the billet using a bandsaw to obtain a cut piece, polish it, etch it with Keller solution (20ml H ₂ O + 20ml HCl + 20ml HNO ₃ + 5 ml HF), and then analyze the image. As a test specimen, metal structures were observed using an image analyzer (LEICA DMR). The result is shown in FIG. 1B. As can be seen from the photograph of FIG. 1B, according to the method of the present invention, a metal material having a uniform and fine spherical grain structure over the surface portion and the center portion can be obtained.

Example 2-5

The same method as described in Example 1 was carried out, except that the temperature of the metal material was injected into the container at 720 ° C. (Example 2), 700 ° C. (Example 3), 650 ° C. (Example 4) and At 620 ° C. (Example 5), when the solid phase ratio of the metal material reached 0.05 (directly above the liquidus temperature), the EMS was stopped, cooled to a solid phase of 0.6, and quenched to prepare a billet. The time taken to complete the process was all within one minute. The billet thus obtained was prepared in the same manner as in Example 1, and then the metal structure was observed. 2 to 5 show image analysis photographs of the specimens obtained in Examples 2 to 5, respectively. As shown in Figures 2 to 5, even when the container injection temperature of the metal material is changed within the temperature range of 720 ℃ ~ 620 ℃ fine and uniform alloy (average particle diameter of the spherical particles 10 ~ 60㎛) is produced It became. Therefore, according to the method of the present invention, spheroidized tissue can be obtained even in a short time of less than one minute. This is because the spacing between the initial crystals is significantly reduced due to the significant increase in nucleation density, so that the shape of the tissue can be kept constant even at faster cooling than the conventional method.

Example 6-9

In the same manner as described in Example 1, except that after the application of the electromagnetic field to cool the metal material, the cooling rate is 0.2 ℃ / sec (Example 6), 0.4 ℃ / sec (Example 7), a metal slurry was obtained at 0.6 ° C / sec (Example 8) and 2.0 ° C / sec (Example 9), and then quenched to prepare a billet. For these billets, specimens were prepared in the same manner as described in Example 1, and then metal structures were observed. The results are shown in FIGS. 6 to 9.

As shown in Figs. 6 to 9, even if the cooling rate is varied in the cooling process of the metal material, the resulting metal structure exhibits spherical shape. In addition, the particles of the metal structure are fine with an average particle diameter of 10 to 60㎛, and the distribution of the spherical particles is also uniform.

Example 10-12

The same method as described in Example 1 was carried out, except that the electromagnetic field was applied at the time when the solid phase ratio was 0.2 (Example 10), when 0.6 was obtained (Example 11), and when 0.7 was obtained (Example 12). Authorization was terminated. Specimens were prepared in the same manner as described in Example 1 and the metallographic structures of the specimens were observed. The results are shown in Figures 10-12.

As can be seen from the photographs of the metal structures of FIGS. 10 to 12, even when the end point of applying the electromagnetic field is varied, the metal structure of the alloy obtained is fine and the distribution of spherical particles is uniform.

Example 13

The same method as described in Example 1 was carried out, but the injection temperature was set to 630 ℃, the metal material was applied at the same time as the injection of the metal material to obtain a metal slurry and then quenched to prepare a billet. For these billets, specimens were prepared in the same manner as described in Example 1, and then metal structures were observed. The results are shown in FIG.

As can be seen from the photograph of the metal structure of Fig. 13, even when the electromagnetic field is applied simultaneously with the injection of the molten metal material, the metal structure of the alloy obtained is fine and the distribution of spherical particles is uniform. That is, there is almost no difference in the metal structure of the alloy obtained even when the molten metal material is not injected while the electromagnetic field is applied in advance, but the application of the electromagnetic field and the injection of the molten metal material are performed at the same time.

Example 14

In the same manner as described in Example 1, the injection temperature is set to 630 ℃, during the injection of the molten metal material (50% injection completion point) by applying an electromagnetic field to obtain a metal slurry and then quenched billet Prepared. For these billets, specimens were prepared in the same manner as described in Example 1, and then metal structures were observed. The results are shown in FIG.

As can be seen from the photograph of the metal structure of Fig. 14, even when an electromagnetic field is applied during injection of the molten metal material, the metal structure of the alloy obtained is fine and the distribution of spherical particles is uniform. That is, even when the molten metal material is injected while the electromagnetic field is applied in advance or the molten metal material is not injected at the same time as the application of the electromagnetic field, the injection is performed even when the electromagnetic field is applied during the injection of the molten metal material. Although the effect is somewhat lower than the previous two cases depending on whether the electromagnetic field is applied in the state of completion, there is little difference in the metal structure of the alloy obtained.

Example 15

The method was carried out in the same manner as described in Example 1 except that the injection temperature was set at 650 ° C., and the application of the electromagnetic field was terminated. Then, the metal material was cooled at a cooling rate of 1.5 ° C./sec until a solid phase rate of 0.6 was reached. . After injection of the metal material, it took 35 seconds to reach a solid phase of 0.6. Specimens were prepared in the same manner as described in Example 1, and metal structures on the surface and center of the specimen were observed. The results are shown in Figs. 15A and 15B, respectively.

Example 16

It is carried out in the same manner as described in Example 1, except that the injection temperature of the metal material into the container is 700 ℃, and after the application of the electromagnetic field is finished, the cooling rate of 1.5 ℃ / sec until the solid state of 0.6 The metal material was cooled by. After injection of the metal material, the time taken to reach a solid phase of 0.6 was 40 seconds. Specimens were prepared in the same manner as described in Example 1, and metal structures on the surface and center of the specimen were observed. The results are shown in FIGS. 16A and 16B, respectively.

Comparative Example 1

For comparison, the same method as described in Example 15 was carried out, but the molten metal material was injected into the container, the EMS was operated for about 10 seconds under the liquidus temperature, and the metal material at a rate of 0.8 ° C./sec. The solid phase was cooled until the solid phase ratio reached about 0.6. After injection of the metal material, the time taken to reach a solid phase of 0.6 was 75 seconds. Specimens were prepared according to the same method as described in Example 1, and the metal structures were observed. The results are shown in FIGS. 17A and 17B.

Comparative Example 2

For comparison, the same method as described in Example 16 was carried out, but the metal material was injected into the container, the EMS was operated for about 10 seconds under the liquidus temperature, and the solid phase of the metal material at a rate of 1.0 ° C./sec. Cool down until the rate reached about 0.6. After injection of the metal material, the time required to reach a solid phase of 0.6 was 85 seconds. Specimens were prepared according to the same method as described in Example 1, and the metal structures were observed. The results are shown in FIGS. 18A and 18B.

Comparing the results of Examples 15 and 16 with Comparative Examples 1 and 2, the metal materials obtained in Examples 15 and 16 according to the method of the present invention exhibited uniform spherical structure of the metal grains at the surface and the center. While the average particle size is uniform and fine with little difference between the surface and the center, the molten metal material is injected into the container according to the conventional method in Comparative Examples 1 and 2, and when the temperature is below the liquidus line, When the reaction force is applied, even though the center part shows spherical particle structure, the surface part shows a dendritic structure, so that the metal structure between the surface part and the center part of the metal material is not uniform. In addition, according to the method of the present invention, the production time of the reaction solid or semi-melt forming metal material is greatly shortened. This is because, in the case of the method of the present invention, a predetermined solid phase rate can be reached even with a short time of crystal growth by increasing the initial nucleation density of the metal material in the container.

As is apparent from the above examples and comparative examples, according to the method of the present invention, it is possible to increase the container injection temperature of the metal material to a high temperature of about 100 ° C. above the liquid phase, and fine through the stirring of the electromagnetic field for a short time. Not only can the alloy be prepared, but also the time required for the preparation of the metal slurry or billet-shaped reaction solid or semi-melt forming metal material can be greatly shortened, and the resulting metal structure of the alloy exhibits a refined spherical particle form. .

Although the present invention has been described in the case of producing a commercially available A356 alloy from a reaction solid or semi-melt molding metal material, the present invention is not limited to the production of the alloy, and of course, various other metals / alloys, eg For example, it is a matter of course that it can be universally applied to the production of aluminum or its alloys, magnesium or its alloys, zinc or its alloys, copper or its alloys, or iron or its alloys.

As described above, according to the method of the present invention, compared to the conventional method, the entire region over the periphery and the center, the upper part and the lower part of the metal material in the container is rapidly lowered below the liquidus temperature without generating the latent solidification heat due to the formation of the initial solidification layer. By cooling, the spheroidization of particles can be realized by significantly increasing the nucleation density, and the overall homogeneous and fine spherical particle distribution can be realized, thereby improving the mechanical properties of the alloy.

In addition, the method for producing the reaction solid or semi-melt forming metal material of the present invention is simple in its process, easy to control the process, and can greatly shorten the electromagnetic stirring time, so the energy consumption required for stirring is reduced and product molding is performed. Time is also shortened, which has significant economic advantages.

Claims (18)

Applying an electromagnetic field to the container; Injecting the molten metal material into the container while the electromagnetic field is applied to the container; Terminating the application of the electromagnetic field to the container after the injection of the metal material is completed; And Cooling step of cooling the metal material in the container; Method of producing a metal material in a solid-liquid coexistence state comprising a. Applying an electromagnetic field to the container; An injection step of injecting the molten metal material into the container at the same time as the application of the electromagnetic field; Terminating the application of the electromagnetic field to the container after the injection of the metal material is completed; And Cooling step of cooling the metal material in the container; Method of producing a metal material in a solid-liquid coexistence state comprising a. delete delete delete delete 3. The solid-liquid coexistence state of claim 1 or 2, wherein the terminating step ends the application of the electromagnetic field according to the applying step when the solid phase rate of the metal material in the container reaches 0.001 to 0.1. Method of manufacturing metal material. delete delete delete delete delete The method according to claim 1 or 2, wherein the cooling step cools the metal material in the container until it reaches a solid phase rate of 0.1 to 0.7. The method according to claim 1 or 2, wherein the cooling step cools the metal material in the container at a rate of 0.2 ° C / sec to 5 ° C / sec. delete The solid solution according to claim 1 or 2, wherein one of aluminum, aluminum alloy, magnesium, magnesium alloy, zinc, zinc alloy, copper, copper alloy, iron, or iron alloy is used as the metal material. Method for producing metal material in coexistence state. delete delete