JP2005088083A - Manufacturing device of metal slurry in solid-liquid coexistent state - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing device of semi-solidified metal slurry of excellent linkage to a succeeding step capable of easily manufacturing and discharging the semi-solidified metal slurry of high quality in a short time. <P>SOLUTION: A lower end of a sleeve 2 is closed by a stopper 3. Molten metal M is poured from an upper end side of the sleeve 2. The electromagnetic field of the intensity with which no initial solidified layer is formed is applied to the molten metal M in the sleeve 2 by a coil device 11 for applying the electromagnetic field of a stirring unit 1. Application of the electromagnetic field by the stirring unit 1 is completed by an electromagnetic field application adjustment unit 16 when crystal nuclei are generated in the molten metal M poured in the sleeve 2. The molten metal M in the sleeve 2 is turned into semi-solidified metal slurry. The lower end side of the sleeve 2 is opened by driving the stopper 3. The semi-solidified metal slurry in the sleeve 2 is dropped by the self weight. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an apparatus for producing a solid-liquid coexistence state metal slurry by applying an electromagnetic field to molten metal to form a solid-liquid coexistence state metal slurry.

  A metal material in a solid-liquid coexistence state, that is, a semi-molten or semi-solid metal slurry, generally refers to an intermediate product of a composite processing method such as a semi-solid forming method (Reocasting) or a semi-melt forming method (Thixocasting). In addition, the liquid phase and spherical crystal grains can be mixed at an appropriate ratio at the temperature of the semi-solidified region, and can be deformed with a small force due to thixotropic properties, and has excellent fluidity and liquid phase. Thus, it is a metal material in a state that is easy to form.

  Here, the semi-solid forming method refers to a processing method of manufacturing a billet or a final formed product by casting or forging a slurry having a predetermined viscosity without being completely solidified. The semi-melt molding method refers to a processing method in which a billet manufactured by a semi-solid molding method is reheated to a semi-molten slurry, and then the slurry is cast or forged to produce a final product.

  Such a semi-solidified or semi-molten molding method has various advantages compared to a general molding method using a molten metal such as casting or melt forging. For example, since the semi-molten metal slurry used in these semi-solid or semi-molten forming methods has fluidity at a lower temperature than the molten metal, the temperature of the die exposed to this slurry can be further lowered than in the case of molten metal, This extends the life of the die.

  Also, when the slurry is pushed out along the cylinder, the generation of turbulent flow is small, and the entry of air during the casting process is reduced, thereby reducing the generation of pores in the final product. In addition, there is little coagulation shrinkage, workability is improved, the mechanical properties and corrosion resistance of the product are improved, and the product can be reduced in weight. As a result, it can be used as a new material in the automobile and aircraft industry fields, electrical and electronic information communication equipment, and the like.

  As described above, in these semi-solid forming methods or semi-melt forming methods, a metal slurry in a semi-solid state is used. As described above, in the semi-solid forming method, a slurry obtained by cooling molten metal by a predetermined method is used. In the semi-melt molding method, a slurry obtained by reheating the billet in the solid phase is used. Here, in the semi-solid metal slurry, the region where the liquid phase and the solid phase coexist between the liquid phase line and the solid phase line of the metal, that is, the crystal grain boundary inside the metal at the temperature of the metal semi-solid region. This means a metal material that is partially dissolved and partially remains as a solid phase component. A semi-solid slurry produced by a semi-solid forming method, that is, cooled from molten metal. Say.

  Further, as a conventional semi-solid forming method, a nucleation method for producing a semi-solid metal slurry by growing a plurality of crystal nuclei in a molten metal and then growing the crystal nuclei by a production process, The method is roughly classified into a stirring method in which a dendritic crystal as an initial solidified layer is grown in a molten metal, and then the dendritic crystal is crushed to produce a semi-solid metal slurry.

  By the way, in the conventional nucleation method, the pouring temperature of the molten metal must be kept very low, and the cooling rate is made very slow to gradually advance the process to generate a plurality of crystal nuclei. These crystal nuclei are grown. For this reason, there is a problem that the manufacturing time of the semi-solid state metal slurry is too long and it is difficult to apply it to an actual mass production process.

  On the other hand, in the conventional stirring method, when the molten metal is cooled, it is mainly stirred at a temperature below the liquidus, and the dendritic crystal structure that has already been formed is crushed to produce spherical particles suitable for semi-solid forming. Is the method. As the stirring method, mechanical stirring method, electromagnetic stirring method, gas bubbling, low frequency, high frequency or electromagnetic wave vibration, stirring method by electric shock, or the like is used.

  And as a method of manufacturing a liquid phase solid phase mixture, it cools, stirring strongly, while a molten metal solidifies. Furthermore, the production apparatus for producing this liquid phase solid phase mixture stirs with a stir bar in a state where the solid liquid mixture is poured into a container, and this stir bar stirs the solid liquid mixture having a predetermined viscosity. To crush the dendritic structure in the mixture or to disperse the crushed dendritic structure (for example, see Patent Document 1).

  However, in the above method for producing a liquid phase solid phase mixture, a dendritic crystal form already formed in the cooling process is pulverized, and a spherical crystal is obtained using the pulverized dendritic crystal as a crystal nucleus. For this reason, there are many problems such as a decrease in cooling rate and an increase in production time due to generation of latent heat due to the formation of an initial solidified layer, and a non-uniform crystal state due to temperature non-uniformity in the stirring vessel. Also in the case of a production apparatus for producing this liquid phase solid phase mixture, the temperature distribution in the container is non-uniform due to the limitations of mechanical agitation, and the working time and subsequent steps for operating in the chamber Linking to has a very difficult limit.

  Moreover, as a manufacturing apparatus of a semi-solid alloy slurry, a cooling manifold and a mold are sequentially provided inside an electromagnetic field applying means with a coil. And the upper side of this metal mold | die is formed so that a molten metal may be poured continuously, and it is comprised so that cooling water may flow into a cooling manifold and a metal mold | die may be cooled. Furthermore, according to the semi-solid alloy slurry manufacturing method using the semi-solid alloy slurry manufacturing apparatus, first, molten metal is poured from the upper side of the mold, and the molten metal passes through the mold by the cooling manifold. A solid phase region is formed. Here, a magnetic field is applied by an electromagnetic field applying means, cooling proceeds while crushing the dendritic tissue, and an ingot is formed from the lower part (see, for example, Patent Document 2).

  However, the semi-solid alloy slurry manufacturing method also has many problems in terms of process and structure because it crushes the dendritic structure by applying vibration after solidification. Also, in the case of the above-mentioned semi-solid alloy slurry manufacturing apparatus, the molten metal continuously forms an ingot while progressing from the upper part to the lower part. By continuously growing the molten metal, the state of the metal is changed. It is difficult to adjust and overall process control is not easy. Furthermore, since the mold is water-cooled before applying the electromagnetic field, the temperature difference between the vicinity of the wall and the center of the mold is extremely large.

  In addition to this, there are various types of semi-solid forming method or semi-melt forming method, and all of them have crushed the dendritic structure in the molten metal that has already been formed, and the dendritic structure is converted into crystal nuclei. It is intended to be used as

  Furthermore, as a method for producing a semi-molten molded material, after heating the alloy so that all metal components in the alloy exist in a liquid state, the obtained liquid metal is brought to a temperature between the liquidus and solidus. Cooling. Thereafter, the dendritic structure formed from the molten metal cooled by applying a shearing force is destroyed to produce a semi-molten molded material (see, for example, Patent Document 3).

  Moreover, as a manufacturing method of the metal slurry for semi-solid casting, molten metal is poured into a container at a temperature close to or higher than the liquidus temperature by 50 ° C. Thereafter, when the molten metal is cooled, at least a part of the molten metal becomes lower than the liquidus temperature, that is, when the molten metal first passes the liquidus temperature, for example, the molten metal is moved by ultrasonic vibration. Add. Furthermore, after applying motion to the molten metal, a metal slurry for semi-solid casting having a metal structure in a grain phase crystal form is manufactured by gradually cooling (see, for example, Patent Document 4).

  However, even in the above-described method for producing a metal slurry for semi-solid casting, a force such as ultrasonic vibration is used for crushing a dendritic crystal structure formed in the initial stage of cooling. If the pouring temperature is higher than the liquid line temperature, it is difficult to obtain a crystal form of the grain phase, and at the same time, it is difficult to cool the molten metal rapidly. Further, the texture of the surface portion and the central portion becomes non-uniform.

  Furthermore, as a method for forming the semi-molten metal, after pouring the molten metal into the container, the vibrating bar is immersed in the molten metal and vibrated in direct contact with the molten metal to give vibration to the molten metal. Yes. Specifically, by transmitting the vibration force of the vibration bar to the molten metal, a solid-liquid coexisting alloy having crystal nuclei at a liquidus temperature or lower is formed. Thereafter, the molten metal is maintained in the vessel for 30 seconds or more and 60 minutes or less while being cooled to a molding temperature exhibiting a predetermined liquid phase ratio, thereby growing crystal nuclei to obtain a semi-molten metal. However, the size of crystal nuclei obtained by this method is about 100 μm, the process time is considerably long, and it is difficult to apply to containers of a predetermined size or more (see, for example, Patent Document 5).

Moreover, as a manufacturing method of a semi-molten metal slurry, a semi-molten metal slurry is manufactured by precisely controlling cooling and stirring simultaneously. Specifically, after pouring molten metal into the mixing container, a stator assembly installed around the mixing container is operated to generate a magnetomotive force sufficient to rapidly stir the molten metal in the container. Further, the temperature of the molten metal is rapidly lowered using a thermal jacket provided around the mixing container and precisely adjusting the temperature of the container and the molten metal. The molten metal continues to be stirred when the molten metal is cooled, provides fast stirring when the solid fraction is low, and is adjusted in a manner that provides increased electromotive force as the solid fraction increases (e.g., patent document 6).
U.S. Pat. No. 3,948,650 (columns 3-8 and FIG. 3) U.S. Pat. No. 4,465,118 (columns 4-12, FIGS. 1, 2, 5, and 6) US Pat. No. 4,694,881 (columns 2-6) Japanese Patent Laid-Open No. 11-33692 (page 3-5 and FIG. 1) JP-A-10-128516 (page 4-7 and FIG. 3) U.S. Pat. No. 6,432,160 (columns 7-15, FIGS. 1A-2B and 4)

  As described above, the conventional semi-solid metal slurry production method and production apparatus use shear force to pulverize the dendritic crystal already formed in the cooling process into a granular metal structure. ing. Therefore, since a force such as vibration is effective only when at least a part of the molten metal falls below the liquidus, various kinds of effects such as a decrease in cooling rate and an increase in production time due to generation of latent heat due to the formation of an initial solidified layer. Difficult to avoid problems. Also, it is difficult to obtain a uniform and fine structure as a whole due to uneven temperature in the container, and the wall surface of the container and the central part are not adjusted unless the temperature of pouring molten metal into the container is adjusted. There is a problem that the non-uniformity of the tissue further increases due to the temperature difference between the two.

  The present invention has been made in view of such points, and can produce a high-quality solid-liquid coexistence state metal slurry in a short time, can be easily discharged, and can improve the connectivity with subsequent processes. An object of the present invention is to provide a slurry manufacturing apparatus.

  The solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 1, wherein the molten metal is accommodated, at least one end is opened, the solid-liquid coexistence state metal slurry is discharged from the opening, and is configured of a nonmagnetic material. A hot water part, an opening / closing means for opening and closing the opening of the pouring part, and a stirring means for applying a predetermined electromagnetic field to the pouring part are provided.

  Then, with the opening at one end of the pouring part closed by the opening / closing means, the molten metal is accommodated in the pouring part, and a predetermined electromagnetic field is applied to the pouring part by the stirring means to fix the molten metal. Produces a metal slurry in a liquid coexistence state. Thereafter, the opening of the pouring part is opened by the opening / closing means, and the solid-liquid coexistence state metal slurry is discharged from this opening. As a result, a high-quality solid-liquid coexisting state metal slurry can be produced in a short time, and the solid-liquid coexisting state metal slurry can be easily discharged from the opening of the pouring part. The connectivity with the subsequent process of the coexisting state metal slurry can be improved. Furthermore, since the pouring part is made of a non-magnetic material, even if an electromagnetic field is applied to the pouring part, induction heating does not occur and no heat is generated. Therefore, the molten metal poured into the pouring part is cooled. It's easy to do. Therefore, the application of the electromagnetic field by the stirring means to the molten metal poured into the pouring part can be more efficiently performed, so that the solid-liquid coexisting state metal slurry can be more efficiently produced.

  The solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 2 is the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 1, wherein the opening / closing means is attached to the opening of the pouring part so as to be openable and closable. It is what is.

  And by using the lid attached to the opening of the pouring part as the opening / closing means, the opening and closing of the opening of the pouring part becomes simpler and the opening and closing of the opening can be made easier. For this reason, it is easier to produce the solid-liquid coexisting state metal slurry in the pouring part, and it is possible to more easily discharge the solid-liquid coexisting state metal slurry from the opening of the pouring part.

  The solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 3 is the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 1, wherein the opening / closing means is a plunger inserted so as to be able to advance and retreat from the opening of the pouring part. There is something.

  The opening / closing means is a plunger inserted so as to be able to advance and retract from the opening of the pouring part, so that the opening and closing of the pouring part can be reliably opened and closed with a simpler configuration. For this reason, the solid-liquid coexistence state metal slurry can be more easily and reliably produced in the pouring part, and the discharge of the solid-liquid coexistence state metal slurry from the opening of the pouring part can be facilitated.

  The solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 4 is the solid-liquid coexistence state metal slurry manufacturing apparatus according to any one of claims 1 to 3, wherein the pouring part has an opening at the other end facing one end. The pressurizing means is inserted through the opening at the other end of the pouring part so as to be able to advance and retreat, and pressurizes the solid-liquid coexisting state metal slurry.

  Then, with the opening at one end of the pouring part closed by the opening / closing means, the solid-liquid coexistence state metal slurry is pressurized by the pressurizing means inserted so as to be able to advance and retreat from the opening at the other end of the pouring part. . As a result, a high-quality solid-liquid coexistence state metal slurry can be produced in a shorter time in the pouring part, and a solid-liquid coexistence state metal slurry having a desired shape can be easily formed with a simple configuration.

  The solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 5 is the solid-liquid coexistence state metal slurry manufacturing apparatus according to any one of claims 1 to 4, wherein an initial solidified layer is formed on the molten metal poured into the pouring part. There is provided a control means for applying an electromagnetic field of a level such that no molten metal is applied by the stirring means before the molten metal is poured into the pouring part.

  Then, the control means is applied by the agitation means before the molten metal is poured into the molten metal portion, so that an electromagnetic field that does not form an initial solidified layer is formed on the molten metal poured into the molten metal portion. Therefore, crystal nuclei can be generated in the molten metal by applying an electromagnetic field to the molten metal without forming an initial solidified layer on the molten metal poured into the molten metal. Therefore, a solid-liquid coexisting state metal slurry can be produced by growing crystal nuclei in the molten metal without generating solidification latent heat due to the formation of an initial solidified layer in the molten metal.

  The solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 6 is the solid-liquid coexistence state metal slurry manufacturing apparatus according to any one of claims 1 to 4, wherein dendritic crystals are added to the molten metal poured into the pouring part. There is provided a control means for applying an electromagnetic field of a level such that no molten metal is applied by the stirring means before the molten metal is poured into the pouring part.

  Then, the control means applies the electromagnetic field of the degree that dendrites are not formed on the molten metal poured into the pouring part by the stirring means before the molten metal is poured into the pouring part. Therefore, crystal nuclei can be generated in the molten metal by applying an electromagnetic field to the molten metal without forming dendritic crystals in the molten metal poured into the molten metal. Therefore, a solid-liquid coexistence state metal slurry can be produced by growing crystal nuclei in the molten metal without generating latent heat of solidification due to the formation of dendritic crystals in the molten metal.

  The solid-liquid coexisting state metal slurry manufacturing apparatus according to claim 7 is the solid-liquid coexisting state metal slurry manufacturing apparatus according to claim 5 or 6, wherein the control means is configured to crystallize the molten metal poured into the pouring part. When the nucleus is generated, the application of the electromagnetic field by the stirring means is terminated.

  Then, when crystal nuclei are generated in the molten metal poured into the pouring part, the application of the electromagnetic field by the stirring means is terminated by the control means, so that the molten metal poured into the pouring part is initialized. Crystal nuclei can be generated in the molten metal in the pouring part without forming a solidified layer. For this reason, since solidification latent heat due to the formation of the initial solidified layer of the molten metal does not occur, a solid-liquid coexistence state metal slurry can be produced by efficiently growing crystal nuclei in the molten metal.

  According to the solid-liquid coexisting state metal slurry manufacturing apparatus according to claim 1, a high-quality solid-liquid coexisting state metal slurry can be produced in a short time, and the solid-liquid coexisting state metal slurry can be easily formed from the opening of the pouring part. Therefore, the connectivity with the subsequent process of the solid-liquid coexistence state metal slurry discharged from the pouring part can be improved. Furthermore, by configuring the pouring part with a non-magnetic material, induction heating does not occur even if an electromagnetic field is applied to the pouring part, and no heat is generated, and the molten metal poured into the pouring part is cooled. Since it is easy to apply the electromagnetic field by the stirring means to the molten metal poured into the pouring part, the solid-liquid coexisting state metal slurry can be produced more efficiently.

  According to the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 2, in addition to the effect of the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 1, the opening / closing means is attached to the opening of the pouring part. By using the lid, the opening and closing of the pouring part can be more easily opened and closed, and the opening and closing of the pouring part can be easily performed. It is possible to easily discharge the metal slurry in the solid-liquid coexistence state from the opening of the pouring part.

  According to the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 3, in addition to the effect of the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 1, the opening and closing means can be moved forward and backward from the opening of the pouring part. By using the inserted plunger, it is possible to reliably open and close the opening of the pouring part with a simpler configuration, so that the solid-liquid coexistence state metal slurry in the pouring part can be manufactured more easily and reliably, The solid-liquid coexistence state metal slurry can be more easily discharged from the opening of the pouring part.

  According to the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 4, in addition to the effects of the solid-liquid coexistence state metal slurry manufacturing apparatus according to any one of claims 1 to 3, the opening at one end of the pouring part is opened and closed. When the metal slurry is pressurized by the pressurizing means inserted so as to be able to advance and retreat from the opening at the other end of the pouring part while being blocked by the means, the pouring part is made shorter in this pouring part. In addition, a high-quality solid-liquid coexisting state metal slurry can be produced, and a solid-liquid coexisting state metal slurry having a desired shape can be easily formed with a simple configuration.

  According to the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 5, in addition to the effect of the solid-liquid coexistence state metal slurry manufacturing apparatus according to any one of claims 1 to 4, the molten metal poured into the pouring part An electromagnetic field that does not form an initial solidified layer on the metal is applied to the molten metal poured into the pouring part by applying a control means with stirring means before the molten metal is poured into the pouring part. Crystal nuclei can be generated in the molten metal by applying an electromagnetic field to the molten metal without forming a solidified layer, so that there is no latent heat of solidification due to the formation of the initial solidified layer in the molten metal. A metal slurry coexisting with solid and liquid can be produced by growing crystal nuclei in the molten metal.

  According to the solid-liquid coexistence state metal slurry manufacturing apparatus according to claim 6, in addition to the effect of the solid-liquid coexistence state metal slurry manufacturing apparatus according to any one of claims 1 to 4, the molten metal poured into the pouring part An electromagnetic field that does not form dendritic crystals on the metal is applied to the molten metal poured into the pouring part by applying a control means with stirring means before the molten metal is poured into the pouring part. Without forming a crystal, the application of an electromagnetic field to the molten metal can generate crystal nuclei in the molten metal, so there is no latent heat of solidification due to the formation of dendritic crystals in the molten metal. A metal slurry coexisting with solid and liquid can be produced by growing crystal nuclei in the molten metal.

  According to the solid-liquid coexisting state metal slurry manufacturing apparatus of claim 7, in addition to the effect of the solid-liquid coexisting state metal slurry manufacturing apparatus of claim 5 or 6, the molten metal poured into the pouring part When crystal nuclei are generated, the application of the electromagnetic field by the stirring means is terminated by the control means, so that an initial solidified layer is not formed on the molten metal poured into the pouring part, and the inside of the pouring part is formed. Since crystal nuclei can be generated in the molten metal, no latent heat of solidification occurs due to the formation of the initial solidified layer of the molten metal. Therefore, a solid-liquid coexisting state metal slurry is produced by efficiently growing the crystal nuclei in the molten metal. it can.

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

  The method for producing a semi-solid metal slurry S used in an apparatus for producing a semi-solid metal slurry S as a solid-liquid coexisting state metal slurry has an electromagnetic field applied before the molten metal M is poured into the sleeve 2 by the pouring process. Apply and stir. That is, before pouring the molten metal M into the sleeve 2, simultaneously with pouring the molten metal M into the sleeve 2, or while pouring the molten metal M into the sleeve 2, ie, while pouring the electromagnetic field, The generation of the initial dendritic tissue is blocked by stirring with. At this time, an ultrasonic wave or the like can be used for the stirring instead of the electromagnetic field.

  That is, the molten metal M is poured by applying an electromagnetic field to the slurry manufacturing region T in the sleeve 2 surrounded by the stirring unit 1 to which the electromagnetic field is applied. At this time, the application of the electromagnetic field is performed with a strength capable of stirring the molten metal M. That is, the application of the electromagnetic field at this time is performed with such strength that the initial solidified layer and the dendritic crystals are not formed on the molten metal M to be poured.

Thereafter, as shown in FIG. 4, for pouring the molten metal M into the sleeve 2 at a pouring temperature T _P as pouring process. At this time, an electromagnetic field is applied to the sleeve 2 so that stirring can be performed. At this time, the electromagnetic field can be stirred simultaneously with the pouring of the molten metal M, and the electromagnetic field can be stirred while the molten metal M is being poured.

  Thus, by performing stirring of the electromagnetic field before the molten metal M is poured into the sleeve 2, the molten metal M is not formed in the initial solidified layer on the inner wall of the low-temperature sleeve 2. Does not grow into dendritic tissue. That is, by pouring molten metal M into the sleeve 2 with an electromagnetic field applied to the sleeve 2, the temperature between the wall surface portion and the central portion, and the upper portion and the lower portion of the sleeve 2 into which the molten metal M has been poured. There is almost no difference. Therefore, the initial solidification near the wall surface of the slurry pouring vessel that occurs in the prior art does not occur, and the entire molten metal M in the sleeve 2 is uniformly cooled rapidly immediately below the liquidus temperature, and many crystal nuclei are simultaneously formed. Can be generated. For this reason, fine crystal nuclei are simultaneously generated over the entire slurry production region T in the sleeve 2, and the entire molten metal M in the slurry production region T is uniformly cooled rapidly immediately below the liquidus temperature. Are simultaneously generated.

  This is because the molten metal M on the surface and the molten metal M on the surface are activated by the active initial stirring action before or after pouring the molten metal M into the slurry production region T or by applying an electromagnetic field simultaneously with the pouring. This is because it is well stirred and heat transfer in the molten metal M is fast, and the formation of an initial solidified layer on the inner wall of the sleeve 2 is suppressed.

  Further, the convective heat transfer between the molten metal M that is well stirred and the inner wall of the low-temperature sleeve 2 is increased, and the temperature of the entire molten metal M is rapidly cooled. That is, the poured molten metal M is dispersed into the dispersed particles by electromagnetic field stirring simultaneously with the pouring, and the dispersed particles are uniformly distributed in the sleeve 2 as crystal nuclei, thereby generating a temperature difference throughout the sleeve 2. No longer. On the other hand, according to the above-described conventional technology, the poured molten metal comes into contact with the inner wall of the low-temperature sleeve and grows as dendritic crystals in the initial solidified layer by rapid convection heat transfer.

  Such a principle can be explained in relation to latent heat of solidification. That is, since the initial solidification of the molten metal M on the wall surface of the sleeve 2 does not occur, no further solidification latent heat is generated, so that the cooling of the molten metal M is simply the specific heat of the molten metal M (about 1/400 of the solidification latent heat). It is possible only by releasing the amount of heat corresponding to

  Accordingly, the dendritic crystals in the initial solidified layer that often occur in the inner wall surface of the slurry pouring container in the prior art are not formed, and the molten metal M in the sleeve 2 extends from the wall surface of the sleeve 2 to the center portion. It shows how the temperature drops uniformly and rapidly as a whole. The time required for lowering the temperature at this time is only a short time of about 1 second to 10 seconds after pouring of the molten metal M. As a result, a large number of crystal nuclei are uniformly generated over the entire molten metal M in the sleeve 2, and the distance between the crystal nuclei becomes very short due to an increase in the crystal nucleation density, so that dendritic crystals are not formed independently. To form spherical particles.

  This is the same when the electromagnetic field is applied while the molten metal M is being poured. That is, by applying the electromagnetic field before the pouring of the molten metal M is completed, the initial solidified layer is not formed on the inner wall surface of the sleeve 2.

At this time, the pouring temperature T _p of the molten metal M is higher than the liquidus temperature, it is desirable to be maintained at a lower temperature than the liquidus + 100 ° C. (melt superheat = 0 ° C. or higher 100 ° C. or less). As described above, since the entire inside of the sleeve 2 into which the molten metal M has been poured is cooled uniformly, there is no need to cool it to near the liquidus temperature before pouring the molten metal M into the sleeve 2. This is because the temperature higher than the liquidus + 100 ° C. may be maintained.

  On the other hand, according to the conventional method of applying an electromagnetic field to a slurry production container when a part of the molten metal falls below the liquidus after pouring molten metal into the slurry production container, While the initial solidified layer is formed, solidification latent heat is generated. However, since the solidification latent heat is about 400 times the specific heat, it takes a long time to lower the temperature of the molten metal in the entire slurry manufacturing vessel. Therefore, in such a conventional method, it is general that the temperature of the molten metal is cooled to about the liquidus or about 50 ° C. higher than the liquidus, and then poured into the slurry production vessel.

Further, when the electromagnetic field stirring is finished, as shown in FIG. 4, even when the molten metal M in the sleeve 2 is partially, when the temperature of the molten metal M falls below the liquidus temperature T ₁ , that is, If the solid phase ratio of the molten metal M is about 0.001 and a predetermined crystal nucleus is formed, there is no problem even if it is finished at any time. In other words, the time when the electromagnetic field stirring is finished is the time when the temperature of the molten metal M in the sleeve 2 reaches near the liquidus. Furthermore, the time when the electromagnetic field stirring is finished is the time when crystal nuclei are uniformly generated in the molten metal M in the sleeve 2.

Here, the nucleation density in the production of semi-solid metal slurry S from the molten metal M, regardless of the alloy system to be used as the molten metal M, the solid phase ratio of the molten metal M is 0.0001 (10 ^{- 4} ) At the point of time, crystal nucleation is completed in all alloy systems. Moreover, it is not easy to measure the solid phase ratio of the molten metal M to a unit of 0.0001. In order to surely terminate the nucleation of the molten metal M used as a raw material of the semi-solid metal slurry S for the purpose of producing a semi-solid metal slurry S that can be used industrially, The phase ratio does not need to be 0.0001, 0.001 or more is sufficient, and more preferably 0.001 or more from the viewpoint of productivity.

  That is, as to how to increase the number of crystal nucleation nuclei in the molten metal M, it is sufficient to apply an electromagnetic field to the molten metal M only while crystal nucleation occurs in the molten metal M. Therefore, even if an electromagnetic field is applied to the molten metal M for a longer time and the solid phase ratio of the molten metal M is set to 0.001 or more, the semi-solid metal slurry S can be manufactured. It is not desirable in terms of energy efficiency to continue to apply an electromagnetic field even when the value of N is 0.1 or more, because the solidified structure of the semi-solid metal slurry S to be produced is coarsened and the process time is increased. Because there is no.

  Further, the electromagnetic field is applied to the sleeve 2 until the molten metal M is poured and cooled until the molten metal M is cooled, and the electromagnetic field is applied before the subsequent pressurizing step, for example, the die casting process or the hot forging process. Stirring may be stopped. This is because the crystal nuclei are already uniformly distributed over the entire slurry manufacturing region T of the sleeve 2, so that the electromagnetic field stirring at the stage where the crystal grains grow around the crystal nuclei is the semi-solid metal slurry S to be manufactured. This is because it does not affect the characteristics of the.

  Therefore, the electromagnetic field stirring is continued at least until the solid phase ratio of the molten metal M becomes 0.001 or more and 0.7 or less. In other words, in the electromagnetic field stirring, when the solid phase ratio of the molten metal M becomes 0.001 or more and 0.7 or less, the application of the electromagnetic field to the sleeve 2 into which the molten metal M is poured is finished. The However, considering the energy efficiency, the duration of the electromagnetic field stirring is maintained until at least the solid phase ratio of the molten metal M in the sleeve 2 is 0.001 or more and 0.4 or less, more preferably the molten metal. This is maintained until the solid phase ratio of M becomes 0.001 or more and 0.1 or less.

  Then, after the electromagnetic field stirring is applied, the manufactured semi-solid metal slurry S is transferred to the outside of the sleeve 2 and connected to the subsequent process. That is, it is transferred to a subsequent die casting process, a hot forging process, and a billet manufacturing process for molding.

  On the other hand, an electromagnetic field is applied before the molten metal M is poured into the sleeve 2 to form crystal nuclei having a uniform distribution, and then the sleeve 2 is cooled as a cooling step to generate crystal nuclei. Accelerate growth. Therefore, such a cooling process may be performed when the molten metal M is poured into the sleeve 2. Moreover, you may apply an electromagnetic field continuously also during this cooling process. Therefore, this cooling step may be performed while an electromagnetic field is applied to the sleeve 2. Thereby, after manufacturing the semi-solid metal slurry S of the semi-solid state with the sleeve 2, this can be immediately used for the forming process which is a subsequent process. Such a cooling process may be performed by a separate temperature adjusting device 20, but may be naturally air-cooled.

Furthermore, such a cooling process can be continued until a molding process as a subsequent process. That is, to maintain the cooling step up to the point t ₂ when the molten metal M reaches the solid fraction of 0.1 to 0.7. That is, when the thickness of the product manufactured by casting the semi-solid metal slurry S is thin and the shape is complicated, it is experimentally cooled until the solid phase ratio of the molten metal M becomes 0.1. This is because it is necessary to make the molten metal M more liquid, to increase the time until the semi-solid metal slurry S is solidified in the mold, and to increase the flow rate of the semi-solid metal slurry S into the mold. .

  On the other hand, when the thickness of the product produced by casting the semi-solid metal slurry S is thick and the shape is simple, until the solid phase ratio of the molten metal M becomes 0.7 experimentally. There is no problem even if the molten metal M is further solidified by cooling and the time until the semi-solid metal slurry S is solidified in the mold is shortened, and the flow rate of the semi-solid metal slurry S is reduced. Because.

  As a result, if the solid phase ratio of the molten metal M used for the production of the semi-solid metal slurry S is set to 0.1 or more and 0.7 or less, the molten metal M can be used regardless of the alloy system used as the molten metal M. With the produced semi-solid metal slurry S, die cast products of any shape can be produced. In addition, the time required from the time when the molten metal M is poured into the sleeve 2 to the time when it is formed into a semi-solid metal slurry S having a solid phase ratio of 0.1 to 0.7 is only 30 seconds to 60 seconds. Absent. Therefore, in order to produce the semi-solid metal slurry S from the molten metal M within 60 seconds, that is, within 1 minute, the solid phase ratio of the molten metal M is cooled to 0.1 or more and 0.7 or less. Good.

  At this time, the cooling rate of the molten metal M is set to about 0.2 ° C./sec or more and 5.0 ° C./sec or less, more preferably 0.2 ° C./sec depending on the distribution of crystal nuclei and the fineness of the particles. s to 2.0 ° C./sec. This is because, when an electromagnetic field is applied to the molten metal M to produce a semi-solid metal slurry S, the generation of crystal nuclei can be performed by applying an electromagnetic field from the viewpoint of the distribution of crystal nuclei and the fineness of particles. This is because the finished molten metal M needs to be cooled at a cooling rate of at least 0.2 ° C./sec.

  That is, when the cooling rate of the molten metal M is set to 0.2 ° C./sec or less, crystal nuclei in the molten metal M grow too much and become too large. Since the time required for producing the slurry S becomes longer, the productivity and mechanical properties of the semi-solid metal slurry S produced from the molten metal M are lowered. For this reason, it is necessary to set the cooling rate of the molten metal M to at least 0.2 ° C./sec or more, and the higher the cooling rate of the molten metal M, the more the semi-solid metal slurry S can be manufactured. It is preferable because the required time can be shortened and energy efficiency can be improved.

  However, when the cooling rate of the molten metal M is set to 5 ° C./sec or more, when the molten metal M is cooled, dendritic crystals are formed in the molten metal M to be dendrited and solidified. Further, when the distance between crystal nuclei formed in the molten metal M is large, the molten metal M is cooled at a relatively slow rate of about 0.2 ° C./sec. Large crystal nuclei in M can be grown. On the other hand, when the distance between the crystal nuclei formed in the molten metal M is small, it is not necessary to grow the crystal nuclei in the molten metal M too much. It is preferable to cool at a relatively fast rate of about sec.

  Furthermore, when the cross-sectional area of the sleeve 2 into which the molten metal M is poured is large, it is preferable to cool the molten metal M at a relatively slow rate of about 0.2 ° C./sec. On the other hand, when the cross-sectional area of the sleeve 2 into which the molten metal M is poured is small, even if the molten metal M is cooled at a relatively fast rate of about 5 ° C./sec, the crystals in the molten metal M are Nuclei can grow sufficiently.

  Here, the generation of crystal nuclei in the molten metal M poured into the sleeve 2 depends on the temperature of the molten metal M when the sleeve 2 is poured, that is, the pouring temperature. In addition, as this pouring temperature, it can show by the heating degree which shows how much it heated from this liquidus temperature like liquidus temperature of molten metal M +100 degreeC. The degree of heating has an important influence on the stage from when the molten metal M is poured into the sleeve 2 until crystal nuclei are generated in the molten metal M.

  On the other hand, the crystal growth from the generation of crystal nuclei in the molten metal M until the solidification of the cast semi-solid metal slurry S is completed is a semi-solid metal slurry S produced from the molten metal M. The thickness of the product produced by casting the steel has an important effect. Therefore, after the generation of crystal nuclei by applying an electromagnetic field, the cooling rate of the molten metal M when growing the crystal nuclei generates crystal nuclei before pouring the molten metal M into the sleeve 2. Depends on the heating degree of the molten metal M and the thickness of the product produced from the semi-solid metal slurry S formed from the molten metal M. That is, if the heating degree of the molten metal M is constant and the thickness of the product is determined, the cooling rate of the cast semi-solid metal slurry S is naturally determined.

  Here, when the heating degree of the molten metal M is high, the number of crystal nuclei generated in the molten metal M, that is, the number of nucleation decreases, so it is necessary to slow down the cooling rate of the molten metal M. is there. In addition, when the heating degree of the molten metal M is low, the number of nucleation generated in the molten metal M increases, so that the cooling rate of the molten metal M can be increased. The particles of the semi-solid metal slurry S can be made finer.

  Accordingly, the cooling rate of the molten metal M is set to 0.2 ° C./sec or more and 5 ° C./sec or less, and the temperature at which the molten metal M is poured into the sleeve 2 is set to the liquidus of the molten metal M + 100 ° C. If it is lower, it is possible to produce a semi-solid metal slurry S in a semi-solid state having a predetermined solid phase ratio within a range that can be used in the foundry industry, and this is immediately transferred to the billet production process in the transfer process. A billet for semi-melt molding is produced by rapid cooling, or it is transferred to a die casting, forging, or pressing process to form a final product.

  At this time, the time for producing the semi-solid metal slurry S can be remarkably shortened, but the metal material in the form of a metal slurry having a solid phase ratio of 0.1 to 0.7 from the time of pouring the molten metal M into the sleeve 2. The time required to form the film is only 30 seconds or more and 60 seconds or less. If a product is molded using the semi-solid metal slurry S thus produced, a uniform and dense spherical crystal structure can be obtained.

  Moreover, this semi-solid metal slurry S can go through a secondary forming step such as die casting, molten metal forging, forging, and pressing again in the secondary forming step. The semi-solid metal slurry S manufactured in a billet shape can be cut into an appropriate length to form a slag, and the slag can be recovered to a semi-molten state through reheating by a reheating process for secondary forming. Furthermore, the metal particles contained in the semi-solid metal slurry S are fine spheres having an average particle size of 10 μm to 60 μm, and the particle size distribution is uniform.

  Next, a semi-solid metal slurry manufacturing apparatus using the above-described semi-solid metal slurry manufacturing method will be described with reference to FIGS.

  The semi-solid metal slurry manufacturing apparatus shown in FIGS. 1 to 3 is a so-called batch type, and includes a sleeve 2 that is a pouring portion as an elongated cylindrical tubular portion that is open at both ends and opened. . The sleeve 2 is formed of a metal which is a non-magnetic material having excellent conductivity and no magnetism so that the molten metal M poured into the sleeve 2 can be rapidly cooled. Further, when the temperature of the sleeve 2 itself is increased to the temperature of the molten metal M, the sleeve 2 itself may be melted. Therefore, the temperature of the sleeve 2 is increased to the temperature of the molten metal M. I can't let you. Therefore, in this sleeve 2, when an electromagnetic field is applied to the molten metal M immediately after pouring the molten metal M into the sleeve 2, the temperature difference between the sleeve 2 and the molten metal M is large. Dendritic crystals are instantly formed around the portion of the metal M that contacts the sleeve 2.

  Further, the sleeve 2 is installed so as to have an axial direction along the vertical direction, and an upper opening 2a formed at the upper end which is one end along the axial direction, and a lower end facing the upper end. Each of the formed lower openings 2b opens in a concentric manner. The sleeve 2 is configured such that liquid molten metal M is poured from the upper opening 2a of the sleeve 2 so that the molten metal M can be accommodated therein. Further, the sleeve 2 discharges a semi-solid metal slurry S manufactured from the molten metal M poured into the sleeve 2 from the lower opening 2b of the sleeve 2. Further, the peripheral surface portion of the sleeve 2 is formed in a tapered shape that gradually expands from the upper opening 2a toward the lower opening 2b. In other words, the peripheral surface portion of the sleeve 2 is expanded so that the inner diameter dimension gradually increases toward the discharge direction of the semi-solid metal slurry S, which is the direction from the upper end side to the lower end side of the sleeve 2. Yes. A cylindrical stirring unit 1 is installed and attached to the periphery of the sleeve 2 as stirring means for applying an electromagnetic field to the molten metal M poured into the sleeve 2.

  In addition, a circular flat plate opening / closing type stopper 3 as a lid as an opening / closing means is attached to the lower opening 2b of the sleeve 2. The stopper 3 closes the lower opening 2b of the sleeve 2 so as to be openable and closable, and forms a bottom portion 5 as a closed portion of the slurry manufacturing region T into which the molten metal M is poured. The stopper 3 opens the lower opening 2b of the sleeve 2 and drops the semi-solid metal slurry S formed in the sleeve 2 by its own weight. It is made to detach | leave outside from the lower side opening part 2b, and is discharged.

  On the other hand, the stirring unit 1 is provided on the flat surface of the upper part of the base plate 14 which is a hollow casing. The base plate 14 is supported horizontally by a support member 15 so as to have a predetermined height from the ground. An electromagnetic field applying coil device 11 as an electromagnetic field applying means is attached to the upper part of the base plate 14. The electromagnetic field applying coil device 11 is supported by a predetermined cylindrical frame 12. A predetermined space 13 to which an electromagnetic field is applied is formed inside the frame 12.

  In the stirring unit 1, an electromagnetic field applying coil device 11 is formed so as to surround a predetermined space 13. Further, the coil device 11 for applying an electromagnetic field applies an electromagnetic field having a predetermined intensity toward the space 13 and agitates the molten metal M in the sleeve 2 accommodated in the space 13 by electromagnetic field. Here, the electromagnetic field applying coil device 11 may be any coil device that can be used for normal electromagnetic field stirring. Further, the stirring unit 1 may be an ultrasonic stirring device such as ultrasonic stirring other than the electromagnetic field.

  Further, as shown in FIG. 1, an electromagnetic field application adjusting unit 16 as a control means for adjusting the application of the electromagnetic field by the stirring unit is electrically connected and connected to the coil device 11 for applying an electromagnetic field. . As the electromagnetic field application adjusting unit 16, a control device is used, and switching means (not shown) that determines the application of power, and electromagnetic that adjusts the applied electromagnetic wave by adjusting voltage, frequency, electromagnetic force, etc. It has wave control means. That is, the electromagnetic field application adjusting unit 16 adjusts the intensity of the electromagnetic field, the operation time, and the like.

  Further, the electromagnetic field application adjusting unit 16 drives the electromagnetic field application coil device 11 of the stirring unit 1 so that the dendritic crystals as the initial solidified layer are not formed on the molten metal M poured into the sleeve 2. That is, an electromagnetic field that does not form dendritic crystals is applied to the sleeve 2 from the stage before the molten metal M is poured into the sleeve 2. Further, the electromagnetic field application adjusting unit 16 applies the electromagnetic field to the sleeve 2 when the temperature of the molten metal M that has been poured reaches near the liquidus, that is, when crystal nuclei are generated in the molten metal M. The coil device 11 for applying an electromagnetic field is adjusted so as to end the process.

  Therefore, the electromagnetic field application adjusting unit 16 adjusts the electromagnetic field application time point of the electromagnetic field application coil device 11 until the produced semi-solid metal slurry S is compressed. You may continue without ending. However, it can stir in an electromagnetic field from the point of energy efficiency to the manufacturing process of the semi-solid metal slurry S. Therefore, the stirring by the electromagnetic field is continued until the solid phase ratio of the semi-solid metal slurry S to be produced is at least 0.001 to 0.7. Further, the stirring by the electromagnetic field is desirably continued until the solid phase ratio of the produced semi-solid metal slurry S is at least 0.001 to 0.4. Furthermore, the stirring by the electromagnetic field is more desirably finished when the solid phase ratio of the molten metal M becomes 0.001 or more and 0.1 or less. In addition, time until it becomes such a solid-phase rate can be investigated beforehand by experiment.

  Next, as shown in FIGS. 1 and 3, the sleeve 2 is positioned inside the stirring unit 1, and the space 13 in the frame 12 is concentric with the frame 12 of the stirring unit 1. Is installed. Here, the sleeve 2 may be fixed in close contact with the frame 12 of the stirring unit 1. The sleeve 2 may be fixed to the base plate 14 and installed.

  Here, the sleeve 2 is configured by a nonmagnetic metal material or a nonmagnetic ceramic material which is a nonmagnetic material as a metal material or an insulating material. Therefore, since the sleeve 2 is made of a non-magnetic material, the sleeve 2 itself does not generate induction heat due to the application of an electromagnetic field, so that the molten metal M poured into the sleeve 2 is cooled. Is advantageous. When the sleeve 2 is formed of a nonmagnetic metal material, it is desirable to use a sleeve having a melting point higher than that of the molten metal M accommodated in the sleeve 2.

  The sleeve 2 has upper and lower ends open to form an upper opening 2a and a lower opening 2b. The lower opening 2b of the sleeve 2 is formed to be closed and opened by the stopper 3. Further, the upper opening 2a of the sleeve 2 is formed so that the molten metal M is poured from the upper side of the sleeve 2 and can be received. That is, the sleeve 2 has a container shape in which a bottom portion 5 which is a lower portion of the sleeve 2 is constituted by the stopper 3. The sleeve 2 may have any structure as long as the lower opening 2b is closed or opened by the stopper 3.

  The sleeve 2 incorporates a thermocouple (not shown), and the thermocouple is electrically connected to the control unit so that temperature information such as molten metal M in the sleeve 2 is sent to the control unit. Also good.

  Further, as shown in FIG. 2, a temperature adjusting device 20 as temperature adjusting means is attached to the outside of the sleeve 2. The temperature adjusting device 20 cools the molten metal M in the sleeve 2 or the semi-solid metal slurry S produced in the sleeve 2. Further, the temperature adjusting device 20 includes a water jacket 22 that is a cooling device as a cylindrical cooling means in which a cooling water pipe 21 is spirally incorporated. The water jacket 22 is concentrically attached to the outside of the sleeve 2 so as to surround the outside of the sleeve 2. Here, the cooling water pipe 21 in the water jacket 22 may be embedded in the sleeve 2. Further, any cooling device other than the cooling water pipe 21 may be used as long as it can cool the molten metal M and the semi-solid metal slurry S in the sleeve 2.

  Further, the temperature adjusting device 20 includes an electric heating coil 23 as a heating device as a heating means. The electric heating coil 23 is concentrically attached so as to be wound around the outer side of the water jacket 22 so as to surround the outer side of the water jacket 22. Here, the heating coil 23 may be any heating mechanism other than the heating coil 23.

  Therefore, the temperature adjusting device 20 may have any configuration as long as the temperature of the molten metal M or the semi-solid metal slurry S in the sleeve 2 can be adjusted. Further, the temperature adjusting device 20 can cool the molten metal M in the sleeve 2 at an appropriate speed. Further, the temperature control device 20 can be installed over the entire sleeve 2, but as shown in FIG. 2, the temperature control device 20 is centrally installed only around the slurry manufacturing region T in which the molten metal M is accommodated in the sleeve 2. You can also The molten metal M in the sleeve 2 may be naturally cooled without providing the temperature adjusting device 20.

  Next, the stopper 3 attached to the lower opening 2b of the sleeve 2 may have a structure that can open and close the lower opening 2b of the sleeve 2. The stopper 3 is driven along the surface direction of the base plate 14 by a separate driving device (not shown) to open and close the lower opening 2b of the sleeve 2 as shown in FIGS. Further, the stopper 3 is made of the same material as the sleeve 2. Further, the stopper 3 may have a door-like shape in which one side is hinged and fixed to the opening edge of the lower opening 2b of the sleeve 2 or the like, even if the stopper 3 is not of this configuration.

  Further, the stopper 3 is driven along the vertical direction that is the discharging direction of the semi-solid metal slurry S discharged from the lower opening 2b of the sleeve 2 to open the lower opening 2b of the sleeve 2. You can also. That is, when the semi-solid metal slurry S is discharged from the lower opening 2b of the sleeve 2, the lower opening of the sleeve 2 is moved downward so as to support the semi-solid metal slurry S. Open 2b.

  Furthermore, when pouring the molten metal M into the sleeve 2, a pouring container 4 is used. In the pouring container 4, liquid phase molten metal M is poured into the upper opening 2 a of the sleeve 2. And as this pouring container 4, the normal bowl electrically connected with the control part, ie, a ladle, can be used. Here, the pouring container 4 may have any configuration as long as the molten metal M can be poured into the sleeve 2 such as directly connecting a furnace in which a metal is melted in addition to a normal pot.

  Next, the operation of the semi-solid metal slurry manufacturing apparatus of the first embodiment will be described.

  First, as shown in FIG. 1, the lower opening 2 b of the sleeve 2 is closed by the stopper 3. Thereafter, application of an electromagnetic field having a predetermined frequency and strength to the slurry manufacturing region T in the sleeve 2 is started by the electromagnetic field application coil device 11 of the stirring unit 1.

  In this state, the molten metal M melted in a separate electric furnace is transferred in the pouring vessel 4 and poured from the upper opening 2a of the sleeve 2 under the influence of the electromagnetic field applied.

  At this time, the application of the electromagnetic field by the electromagnetic field application coil device 11 is performed before pouring the molten metal M, simultaneously with the pouring of the molten metal M, or is applied while the molten metal M is being poured. You may do it.

  Further, in a state where the molten metal M is poured from the upper opening 2a of the sleeve 2, the molten metal M of the sleeve 2 is supplied to the temperature adjusting device 20 until a solid phase ratio of 0.1 to 0.7 is reached. The semi-solid metal slurry S is manufactured from the molten metal M in the sleeve 2 after being cooled at a predetermined speed.

  Here, the cooling rate by the temperature control device 20 at this time is 0.2 ° C./sec or more and 5 ° C./sec or less, and more preferably 0.2 ° C./sec or more and 2 ° C./sec or less.

  The molten metal M in the sleeve 2 can be naturally cooled without using the temperature adjusting device 20, and a semi-solid metal slurry S having a predetermined solid phase ratio can be produced from the molten metal M.

  On the other hand, the application of the electromagnetic field by the electromagnetic field application coil device 11 is continued until the cooling is completed. That is, the application of the electromagnetic field by the electromagnetic field application coil device 11 is continued until the solid phase ratio of the molten metal M in the sleeve 2 is at least 0.001 to 0.7.

  However, in order to stir the electromagnetic field up to the production process of the semi-solid metal slurry S in the energy efficiency dimension, stirring of the electromagnetic field by the electromagnetic field applying coil device 11 has at least a solid phase ratio of the molten metal M of at least 0.001. More preferably, it is maintained until the solid phase ratio of the molten metal M becomes 0.001 or more and 0.1 or less until it becomes 0.4 or less.

  Here, the time for which the application of the electromagnetic field by the electromagnetic field application coil device 11 is continued can be obtained in advance by an experiment. Further, while the electromagnetic field is being applied by the electromagnetic field applying coil device 11, the molten metal M poured into the sleeve 2 may be continuously cooled and advanced.

  After the semi-solid metal slurry S is manufactured in this way, the lower opening 2b of the sleeve 2 is opened by driving the stopper 3 as shown in FIG. Then, the semi-solid metal slurry S in the sleeve 2 is separated from the lower opening 2b of the sleeve 2 to the outside by its own weight and discharged.

  At this time, a transfer device (not shown) is installed outside the lower opening portion 2b of the sleeve 2, and the semi-solid metal slurry S discharged from the lower opening portion 2b of the sleeve 2 is removed by the transfer device. Then, it is transferred to a molding apparatus (not shown) in the subsequent process to advance semi-solid molding.

  In addition, a sleeve, which is a pouring part as an elongated cylindrical tubular portion (not shown) provided with a cooling device, is provided below the lower opening 2b of the sleeve 2, and is discharged from the sleeve 2 by this sleeve. The semi-solid metal slurry S can be immediately formed into a billet.

  As a result, a semi-solid metal slurry S and a semi-solid molded product having a fine spherical shape with an average particle size of 10 μm to 60 μm and a uniform particle size distribution are manufactured.

  As described above, according to the first embodiment, an electromagnetic field is previously generated in the stirring unit 1 so that an initial solidified layer, that is, a dendritic crystal, is not formed in the molten metal M poured into the sleeve 2. Is applied to the sleeve 2, the molten metal M is poured into the sleeve 2, an electromagnetic field is applied to the molten metal M poured into the sleeve 2, and crystal nuclei are contained in the molten metal M. Is generated.

  When the nucleation in the molten metal M is completed, the application of the electric magnetic field to the sleeve 2 by the stirring unit 1 is terminated, and then the molten metal M is brought near the liquidus by the temperature control device 20. The crystal nuclei produced in the molten metal M are allowed to cool to a large amount, and a large amount of finer and overall uniform spheroidized metal slurry S can be obtained. Improvements in mechanical properties can be realized, energy efficiency can be improved, manufacturing costs can be reduced, casting processes can be simplified, and manufacturing time can be reduced.

  At the same time, the semi-solid metal slurry S produced can be removed from the lower opening 2b of the sleeve 2 to further facilitate the discharge of the semi-solid metal slurry S. As a result, the production and discharge of the high-quality semi-solid metal slurry S can be easily performed in a short time, so that the linkage with the subsequent process can be improved and the production efficiency can be greatly improved.

  Further, the nucleation density of the molten metal M on the wall surface of the sleeve 2 can be remarkably increased by only a short electromagnetic field stirring at a temperature higher than the liquidus, thereby realizing particle spheroidization. For this reason, since the whole process can be simplified and the electromagnetic field stirring time can be greatly shortened, the consumption of energy required for stirring is reduced, and the product molding time can be shortened, so that the economy can be improved.

  Furthermore, since high-quality semi-solid metal slurry S can be produced in large quantities continuously, the linkage with subsequent processes can be further improved, so that the manufacturing efficiency of the entire process can be improved and the configuration of the entire apparatus can be simplified. A large amount of semi-solid metal slurry S can be manufactured more quickly and easily.

  Further, the sleeve 2 is formed in a tapered shape in which the peripheral surface of the sleeve 2 gradually expands from the upper opening 2a side to the lower opening 2b side. Since the semi-solid metal slurry S slides down from the lower opening 2b of the sleeve 2 and falls due to the dead weight of the semi-solid metal slurry S produced in the sleeve 2 just by opening the sleeve 2, The semi-solid metal slurry S can be more easily discharged from the side opening 2b.

  In the first embodiment, the semi-solid metal slurry S produced in the sleeve 2 is dropped by its own weight by driving the stopper 3 to open the lower opening 2b of the sleeve 2. However, as in the second embodiment shown in FIG. 5, the sleeve is provided with a pressurizing plunger 51 which is a pressing means as a pressing means inserted so as to be able to advance and retreat from the upper opening 2a of the sleeve 2. The semi-solid metal slurry S in 2 can be pressed and extruded toward the lower opening 2b.

  At this time, the pressurizing plunger 51 is connected to a driving device (not shown), and is attached to the upper opening 2a side of the sleeve 2. Further, the pressurizing plunger 51 is separated from the sleeve 2 when the molten metal M is poured into the sleeve 2. Further, after the molten metal M is poured into the sleeve 2, the pressurizing plunger 51 is inserted from the upper opening 2 a side of the sleeve 2 so as to advance and retreat.

  As a result, the pressurizing plunger 51 pressurizes the semi-solid metal slurry S from the upper opening 2a side while the semi-solid metal slurry S is generated from the molten metal M by electromagnetic field stirring and cooling. The pressurizing plunger 51 pressurizes the semi-solid metal slurry S after the semi-solid metal slurry S has been manufactured and the lower opening 2b of the sleeve 2 is opened by the stopper 3. It is made to discharge outside from the lower opening 2b.

  At this time, the pressurizing plunger 51 gives the semi-solid metal slurry S manufactured in the sleeve 2 a chance to drop the semi-solid metal slurry S into the lower opening 2b of the sleeve 2. It is only necessary to pressurize the upper side of the semi-solid metal slurry S. Here, the pressure plunger 51 may have any configuration as long as the contents in the sleeve 2, that is, the molten metal M, the semi-solid metal slurry S, and the like can be pressurized from the upper opening 2a of the sleeve 2.

  Furthermore, as in the third embodiment shown in FIGS. 6 and 7, a plunger 32 as a pressing means can be inserted into the lower opening 2b of the sleeve 2 as an opening / closing means so as to be able to advance and retreat. The plunger 32 is driven by a separate driving device (not shown). That is, as shown in FIG. 6, the plunger 32 is inserted into the lower opening 2b of the sleeve 2 to close the lower opening 2b of the sleeve 2 and The bottom 5 of the slurry manufacturing region T is formed below the side opening 2b.

  Further, after the semi-solid metal slurry S is manufactured in the sleeve 2, the plunger 32 is moved downward and lowered as shown in FIG. The sleeve 2 is discharged and separated. As a result, since the semi-solid metal slurry S discharged from the sleeve 2 can be stably supported by the upper end surface of the plunger 32, the semi-solid metal slurry S can be supported by the plunger 32 using a separate robot device (not shown). It can be transferred to another process by the transfer means.

  Next, as in the fourth embodiment shown in FIG. 8, a separate pressure plunger 51 is further installed in the upper opening 2 a of the sleeve 2, and the semi-solid metal in the sleeve 2 is formed by this pressure plunger 51. The slurry S can be pressurized and discharged. As a result, a large amount of semi-solid metal slurry S can be produced continuously, and the connectivity with subsequent processes can be further enhanced, so that the efficiency of the entire process can be improved. Further, by removing the produced semi-solid metal slurry S from the lower opening 2b of the sleeve 2, the discharge of the semi-solid metal slurry S can be further facilitated.

  Further, in each of the above-described embodiments, any of the semi-solid forming methods such as various metals or alloys such as aluminum, aluminum alloy, magnesium, magnesium alloy, zinc, zinc alloy, copper, copper alloy, iron and iron alloy can be used. But it can be applied universally. In other words, any material that can be used for solid-liquid co-molding, so-called semi-solid or semi-melt molding, can be used, and among them, it is selected from the group consisting of aluminum, magnesium, copper, zinc, iron and alloys thereof. It is desirable. These alloys can contain various arbitrary metals depending on the physical properties required in the final molded product.

  That is, this is not a problem as to what alloy system is used as the molten metal M, and considering the theory of solidification, the temperature of the molten metal M before pouring into the sleeve 2 is that of the alloy system used as the molten metal M. Can be discussed in terms of specific heat. Therefore, whether the temperature of the molten metal M before pouring into the sleeve 2 can be higher than the liquidus of the alloy system used as the molten metal M, the specific heat value itself is a problem. Become.

  The specific heat of aluminum is about 0.25 kcal / g. Other alloy systems other than aluminum, such as magnesium (about 0.18 kcal / g), zinc (about 0.1 kcal / g), copper (about 0 .1 kcal / g) and iron (about 0.1 kcal / g) are smaller in specific heat than aluminum. Therefore, other alloy systems other than aluminum have the effect that less heat has to be taken away than aluminum. Therefore, the molten metal M of any of these alloy systems is liquidus + 100 ° C. Even if the metal M is poured into the sleeve 2, an initial solidified layer is not formed on the molten metal M, and no latent heat is generated from the molten metal M. For this reason, if only specific heat is taken from these molten metals M, crystal nuclei in these molten metals M can be grown, so that any of these alloy systems can provide the same effects.

Theoretically, the difference between the temperature changing from the liquid phase to the solid phase (T ₁ ) and the temperature changing from the solid phase to the liquid phase (T _S ), ie, T ₁ −T _S = ΔT is not 0 In any alloy system, crystal nuclei can be formed in the molten metal M by adjusting the temperature of the molten metal M between T ₁ and T _S.

  On the other hand, pure aluminum generally used in the casting industry contains about 1% of impurities. For each of magnesium, zinc, copper and iron other than aluminum, pure magnesium, pure zinc, pure copper and pure iron generally used in the foundry industry contain about 1% impurities.

Therefore, the difference between the temperature changing from the liquid phase to the solid phase (T ₁ ) and the temperature changing from the solid phase to the liquid phase (T _S ) is not 0, the specific heat is smaller than that of aluminum, and the application of the electromagnetic field Even in the case of magnesium, zinc, zinc alloy, copper, copper alloy, iron and iron alloy in which a magnetic field is formed in the molten metal M, the same result as that of the aluminum alloy can be obtained in principle.

  In addition, the sleeve 2 is attached to the frame 12 with the axial direction of the sleeve 2 being along the vertical direction. If the axial direction of the sleeve 2 is at least along the direction having the vertical component, The same effects as those in the above embodiments can be obtained. Furthermore, even if the axial direction of the sleeve 2 is horizontal, it can be used correspondingly.

  Further, after pouring the molten metal M into the sleeve 2, an electromagnetic field is applied to the molten metal M poured into the sleeve 2 by the electromagnetic field applying coil device 11, and the molten metal M Even the semi-solid metal slurry S manufacturing apparatus for manufacturing the solid metal slurry S can be used by adjusting the control of the electromagnetic field application adjusting unit 16.

  In addition, if the lower end which is at least one end of the sleeve 2 is open so that the molten metal M can be accommodated in the sleeve 2 and the semi-solid metal slurry S manufactured in the sleeve 2 can be discharged, Even if the upper end which is the other end of the sleeve 2 is not open, it can be used correspondingly.

  According to the present invention, a semi-solid metal slurry can be produced, and a semi-melt forming billet can be produced using the semi-solid metal slurry. Further, various metal molded products can be manufactured by molding the billet for semi-melt molding by a semi-melt molding method. In addition, the semi-solid metal slurry produced according to the present invention can be formed into a metal molded product through secondary molding such as die casting and extrusion.

It is a schematic sectional drawing which shows the molten metal pouring process of the manufacturing apparatus of the solid-liquid coexistence state metal slurry of the 1st Embodiment of this invention. It is a schematic sectional drawing which shows the temperature control means of the manufacturing apparatus of a metal slurry coexistence state same as the above. It is a schematic sectional drawing which shows the solid-liquid coexistence state metal slurry taking-out process of the manufacturing apparatus of a solid-liquid coexistence state metal slurry same as the above. It is a secondary graph which shows the pouring temperature of the molten metal with respect to time in the manufacturing apparatus of a solid-liquid coexistence state metal slurry same as the above. It is a schematic sectional drawing which shows 2nd Embodiment of the manufacturing apparatus of the solid-liquid coexistence state metal slurry of this invention. It is a schematic sectional drawing which shows the molten metal pouring process of 3rd Embodiment of the manufacturing apparatus of the solid-liquid coexistence state metal slurry of this invention. It is a schematic sectional drawing which shows the solid-liquid coexistence state metal slurry taking-out process of the manufacturing apparatus of a solid-liquid coexistence state metal slurry same as the above. It is a schematic sectional drawing which shows 4th Embodiment of the manufacturing apparatus of the solid-liquid coexistence state metal slurry of this invention.

Explanation of symbols

1 Stirring section as stirring means 2 Sleeve as pouring section
2a Upper opening as opening
2b Lower opening as opening 3 Stopper as lid as opening / closing means
16 Electromagnetic field application adjustment unit as control means
32 Plunger as opening and closing means
51 Pressurizing Plunger as Pressurizing Means M Molten Metal S Solid-Liquid Coexisting Metal Slurry as Metal Slurry

Claims (7)

Molten metal is accommodated, at least one end is opened, a solid-liquid coexistence state metal slurry is discharged from this opening, and a pouring part constituted by a nonmagnetic material,
Opening and closing means for opening and closing the opening of the pouring part,
An apparatus for producing a solid-liquid coexisting state metal slurry, comprising: stirring means for applying a predetermined electromagnetic field to the pouring part. The apparatus for producing a solid-liquid coexistence state metal slurry according to claim 1, wherein the opening / closing means is a lid attached to the opening of the pouring part so as to be opened and closed. The apparatus for producing a solid-liquid coexistence state metal slurry according to claim 1, wherein the opening / closing means is a plunger inserted so as to be able to advance and retreat from the opening of the pouring part. The pouring part opens at the other end opposite to one end,
The solid-liquid coexistence state metal according to any one of claims 1 to 3, further comprising a pressurizing means that is inserted through the opening at the other end of the pouring part so as to advance and retreat and pressurizes the solid-liquid coexistence state metal slurry. Slurry manufacturing equipment. Provided with a control means for applying an electromagnetic field by the stirring means before the molten metal is poured into the molten metal before the molten metal is poured into the molten metal poured into the molten metal. The solid-liquid coexistence state metal slurry production apparatus according to any one of claims 1 to 4. It has a control means for applying an electromagnetic field to the extent that dendritic crystals are not formed on the molten metal poured into the pouring part by the stirring means before the molten metal is poured into the pouring part. The solid-liquid coexistence state metal slurry production apparatus according to any one of claims 1 to 4. 7. The solid-liquid coexistence state metal according to claim 5 or 6, wherein the control means terminates the application of the electromagnetic field by the stirring means when the crystal nucleus is generated in the molten metal poured into the pouring part. Slurry manufacturing equipment.

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