JPH0976051A - Forming method for semi solid metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a product having the fine primary crystal and reduced oxide by removing the upper face of semi solid metal held in a heat insulating container with a jig while cooling the upper face to the molding temp. and inserting the metal into an injection sleeve for pressurizing/forming. SOLUTION: A metal M being prefect liquid in a ladle 10 in a process (1) is poured into a heat insulating ceramic container 30 in a process (2) with using a cooling jig 20 while generating a crystal nucleus from the low temp. molten metal, the alloy right under the liquidus having many crystal nuclei is obtained, In the heat insulating container 30 in a third process, by holding the metal in a semi solid state, an extra fine non-dendrite primary crystal is produced from an introduced crystal nucleus and then is grown to a spherical primary crystal while increasing a solidus rate along temp. lowering of the molten body. At the end of the third process, an oxide W generated at the upper face is removed with the jig. This metal M is inserted into an injection sleeve 40 and pressurized/formed in a die cavity 50a, thereby the product having the fine primary crystal and the reduced oxide is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a semi-molten metal, and more particularly to an alloy in a liquid state having a crystal nucleus at a liquidus temperature or higher, or an alloy having a crystal nucleus in a liquid state at a temperature higher than the forming temperature. Or, holding the alloy having crystal nuclei in a solid-liquid coexisting state at a temperature higher than the molding temperature for 5 seconds to 60 minutes while cooling to a molding temperature exhibiting a predetermined liquid phase ratio in a heat insulating container having a heat insulating effect. The present invention relates to a method for forming a semi-molten metal in which a fine primary crystal is generated in a liquid and then pressure forming is performed.

[0002]

2. Description of the Related Art Thixocasting has attracted attention recently because it has fewer casting defects and segregation than conventional casting methods, has a uniform metal structure, has a long mold life, and has a short molding cycle. Technology. This molding method (A)
The billet used in (1) is characterized by a spheroidized structure obtained by carrying out mechanical stirring or electromagnetic stirring in the semi-melting temperature region, or by utilizing recrystallization after processing. On the other hand, a method of semi-solid molding using a material obtained by a conventional casting method is also known. This is, for example, a method (B) of adding Zr or a method (C) of using a carbon-based refiner in order to produce finer crystals in a magnesium alloy that is likely to generate an equiaxed crystal structure.
In addition, it is a method (D) of adding Al-5% Ti-1% B mother alloy as a refining agent in an aluminum alloy about 2 to 10 times that of the conventional method, and the material obtained by these methods is semi-melted. This is a method in which the primary crystal is heated to a temperature range so as to be spherical and then molded. Also, for alloys within the solid solubility limit, after heating relatively quickly to a temperature near the solidus, the material exceeds the solidus in order to equalize the temperature of the entire material and prevent local melting. A method (E) of forming by heating gently to an appropriate temperature at which the material is softened is known. On the other hand, unlike the method of heating the billet to the semi-melting temperature range and molding,
A rheocast method (F) is known in which a melt containing spherical primary crystals is continuously produced, and the billet is not solidified once but is shaped as it is.

[0003]

However, the above-mentioned method (A) is complicated in both cases of the stirring method and the method of utilizing recrystallization, and there is a drawback that the manufacturing cost becomes high. In addition, in the case of the magnesium alloy, the method (B) has a high Zr and is a problem in terms of cost, and the method (C) uses a carbide-based refiner to sufficiently exert its refinement effect. In order to do so, Be which is an antioxidant element
Should be controlled to a low level of, for example, 7 ppm,
Oxidative combustion is likely to occur during the heat treatment immediately before molding, which is inconvenient for work. On the other hand, in the case of an aluminum alloy, it is about 500 μm if only the refiner is added.
It is not easy to obtain a fine grain structure of 0 μm or less. Therefore, a method of adding a large amount of refiner (D)
However, the refiner tends to settle on the bottom of the furnace and is industrially difficult, and the cost is high. Further, in the method (E), a thixo-molding method characterized by uniform heating and spheroidization of the material by gradually heating after exceeding the solidus line has been proposed. However, it does not change into the thixo structure (the primary dendrite is spheroidized). Moreover, in any of the thixomolding methods (A) to (E), it is necessary to once solidify the liquid phase and raise the billet again to the semi-melting temperature region in order to perform the semi-melt molding, as compared with the conventional casting method. And the cost will increase. Also, (F)
In this method, since a melt containing a spherical primary crystal is continuously generated and supplied, it is more advantageous in cost and energy than thixocasting, but a machine for producing a metal raw material composed of a spherical structure and a liquid phase. It is complicated to link the equipment with the casting machine that manufactures the final product. The present invention focuses on the problems of each of the above-mentioned conventional methods, has a fine primary crystal with few oxides, without using a billet, and without taking a complicated method. The purpose is to obtain a semi-molten metal and press-mold it.

[0004]

In order to solve such a problem, according to the first aspect of the present invention, an alloy in a liquid state having a liquidus temperature equal to or higher than a liquidus temperature having crystal nuclei or crystal nuclei is formed. By holding the alloy in a solid-liquid coexisting state at or above the molding temperature for 5 seconds to 60 minutes while cooling it to a molding temperature showing a predetermined liquid phase ratio in a heat insulating container having a heat insulating effect In the process of crystallizing a primary crystal in the alloy liquid and supplying the alloy to a molding die to perform pressure molding, the upper surface of the semi-molten metal held in the heat insulating container is molded immediately after pouring. After being removed by a metal or non-metal jig until the temperature reached, the semi-molten metal was inserted into an injection sleeve and pressure-molded. A second aspect of the present invention is the method of producing crystal nuclei according to the first aspect of the present invention, in which a molten alloy having a superheat degree of less than 300 ° C. with respect to a liquidus temperature is treated at a temperature lower than a melting point of the alloy. It was decided to contact the surface of the ingredient. Further, in the third invention, the jig of the second invention is a metal jig or a non-metal jig, or a metal jig whose surface is coated with a non-metal material including a semiconductor,
Alternatively, the jig is made of metal that is a composite of non-metallic materials including semiconductors, and the jig can be cooled from inside or outside the jig. In the fourth invention, the crystal nuclei are generated by using a jig or a heat insulating container,
Alternatively, vibration is applied to the molten alloy that contacts both. In the fifth invention, the alloy of the first invention or the second invention is an aluminum alloy having a composition within the maximum solid solution limit or a hypoeutectic aluminum alloy having a composition not less than the maximum solid solution limit. Further, in the sixth invention, the alloy of the first invention or the second invention is a magnesium alloy having a maximum solid solution in-limit composition. A seventh invention is the aluminum alloy of the fifth invention,
B is 0.001% to 0.01% and Ti is 0.005% to
The aluminum alloy was added with 0.3%. Further, in the eighth invention, the magnesium alloy of the sixth invention is added with Sr.
Alloy containing 0.005% to 0.1% of
Alternatively, Si is 0.01% to 1.5% and Sr is 0.0.
05% -0.1% added magnesium alloy or C
The magnesium alloy was prepared by adding a to 0.05% to 0.30%. Furthermore, in the ninth aspect of the invention, the molten aluminum alloy having a degree of superheat with respect to the liquidus temperature of less than 100 ° C. is directly poured into a heat insulating container without using a jig. In the tenth aspect of the invention, the magnesium alloy molten metal having a degree of superheat with respect to the liquidus temperature of less than 100 ° C. is poured directly into a heat insulating container without using a jig.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION An alloy in a liquid state above the liquidus having crystal nuclei or an alloy in the solid-liquid coexisting state above the forming temperature having crystal nuclei, for example, an aluminum alloy melt or a magnesium alloy melt is provided with a heat insulating effect. In the process of generating fine and spheroidized primary crystals in the liquid by holding for 5 seconds to 60 minutes while cooling to the molding temperature in the heat insulating container that it has, immediately after pouring until reaching the molding temperature. ,
By removing the upper surface of the semi-molten state with a metal or non-metal jig and inserting the alloy into an injection sleeve for pressure molding, there is little oxide inclusion and stable mechanical properties are retained. An excellent molded product can be obtained.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 8 relate to an embodiment of the present invention,
FIG. 1 is a process explanatory view showing a method for forming a semi-molten metal of a hypoeutectic aluminum alloy having a composition equal to or more than the maximum solid solubility limit, and FIG. FIG. 3 is an explanatory view of a process showing a method, FIG. 3 is an explanatory view of a process from generation of a spherical primary crystal to molding, and FIG.
6 is a schematic diagram of the metallographic structure of each step shown in FIG. 5, FIG. 5 is an Al-Si alloy equilibrium state diagram which is a typical aluminum alloy, FIG.
Is an Mg-Al alloy equilibrium diagram which is a typical magnesium alloy, FIG. 7 is a copy of a micrograph showing the metal structure of the molded product of the present invention, and FIG. 8 is a microscope showing the metal structure of the molded product of the comparative example. The copy figure of a photograph is shown.

In the present invention, as shown in FIG. 1, FIG. 2, FIG. 5 and FIG. 6, first of all, (1) above the maximum solid solubility limit at which the superheat degree is kept below 300.degree. A hypoeutectic aluminum alloy of composition or a magnesium alloy of maximum solid solubility limit composition, a molten metal of an aluminum alloy is contacted with the surface of a jig having a temperature lower than the melting point of the alloy to generate crystal nuclei in the liquid, Or (2) an aluminum alloy containing an element that promotes the formation of crystal nuclei whose superheat degree to the liquidus temperature is kept below 100 ° C.,
The molten magnesium alloy is directly poured into a heat insulating container having a heat insulating effect without using a jig, and the temperature is kept below the liquidus temperature and higher than the eutectic temperature or the solidus temperature in the heat insulating container. By holding for a period of from 60 seconds to 60 minutes, a large number of fine spherical primary crystals are generated and molded at a predetermined liquid phase rate. The predetermined liquid phase ratio means the amount ratio of the liquid phase suitable for pressure molding, and in high pressure casting such as die casting and squeeze casting, the liquid phase ratio is 20% to 90%, preferably 30% to 70%.
(If it is less than 30%, the material has poor moldability, and if it is 70% or more, it is difficult to handle because the material is soft, and it is difficult to obtain a uniform structure.)
0.1% to 70%, preferably 0.1% to 50% (50
% Or more may cause non-uniformity of the tissue).
The heat-insulating container in the present invention is a metal container or a non-metal container, or a metal container having a surface coated with a non-metal material containing a semiconductor, or a composite of a non-metal material containing a semiconductor. The container is made of metal, and the container can be heated or cooled from inside or outside.

Specifically, the work is carried out according to the following procedure. In the step [1] of FIG. 3 and FIG. 4, the metal M, which is the complete liquid contained in the ladle 10, is processed in the step [2].
In (a), a cooling jig 20 is used to generate crystal nuclei from a low-temperature molten metal (an element that promotes crystal nucleation is also added if necessary) and is poured into a ceramic container 30 having a heat insulating effect, or ( b) A low-temperature molten metal directly above the melting point containing a fine structure generation promoting element directly has a heat insulating container 30 having a heat insulating effect.
By pouring into (ceramic coating metal container 30A), an alloy immediately below the liquidus line containing a large number of crystal nuclei is obtained. Next, in the step [3], the heat insulating container 3
Hold the alloy in the semi-molten state at 0 (or 30 A). During this period, extremely fine non-dendritic primary crystals are generated from the introduced crystal nuclei ([3] -a), and grow as spherical primary crystals as the solid fraction increases with the temperature decrease of the melt ( [3] -c). Then, at the end of this step, the oxide W generated on the upper surface of the semi-molten metal is removed by using a metal or non-metal jig. The metal M having a predetermined liquid phase ratio thus obtained is inserted into the die-casting injection sleeve 40 as shown in [3] -d, and then pressure-molded in the die cavity 50a of the die-casting machine. Obtain a molded product.

The difference between the present invention shown in FIGS. 1, 2, 3 and 4 and the conventional thixocast method and rheocast method is clear from the drawings. That is, in the present invention, unlike conventional methods, the dendrite-like primary crystals crystallized in the semi-melting temperature region are not forcibly crushed into spherical particles by mechanical stirring or electromagnetic stirring, and the crystal nuclei introduced into the liquid A large number of primary crystals that crystallize and grow with a decrease in temperature in the semi-melting temperature region starting from the starting point are continuously spherical due to the amount of heat the alloy itself has (may be externally heated and held if necessary) It is a very simple method because the step of semi-melting by reheating the billet in the thixocasting method is omitted. Each step described above, that is, FIG.
The casting condition, the spheroidizing condition and the molding condition set in each of the step of pouring into the cooling jig 20, the generation of the primary crystal, the spherical process, and the molding process shown in FIG. The reasons for limiting the numerical values shown in the eighth invention, the ninth invention, and the tenth invention will be described below.

When the casting temperature is higher than the melting point by 300 ° C. or higher, or when the surface temperature of the jig 20 is higher than the melting point, (1) the generation of crystal nuclei is small, and (2) the heat insulation has a heat insulating effect. Molten metal M when poured into a container
Since the temperature is higher than the liquidus line, the proportion of remaining crystal nuclei is low and the size of the primary crystal becomes large. For this reason, the casting temperature is 300 ° C for the liquidus.
And the surface temperature of the jig is lower than the melting point of the alloy. A finer primary crystal size can be obtained by setting the superheat degree to the liquidus below 100 ° C. and by lowering the temperature of the jig 20 by 50 ° C. or more below the melting point of the alloy M. . The method for bringing the molten metal M into contact with the jig 20 includes moving the molten metal M on the surface of the jig (flowing the molten metal to the inclined jig 20) and moving the molten metal M to the jig 20.
There are two types of cases where a person moves. The jig mentioned here refers to a jig that gives a cooling action to the molten metal when the molten metal flows down, but instead of this, for example, a tubular pipe of a water heater may be used. The heat insulating container 30 that holds the molten metal that has fallen just below the liquidus line has a heat insulating effect in order to make the generated primary crystals spherical and achieve a desired liquidus ratio after a predetermined time. The material is not limited, and it is preferable that the material has heat retention and has poor wettability with the molten metal.
Further, when a breathable ceramic container is used as the heat insulating container 30, it is desirable to make the outside of the container a predetermined atmosphere (inert atmosphere, reduced pressure atmosphere, etc.) because the magnesium alloy easily oxidizes and burns. Further, in order to prevent oxidation, it is desirable to add Be and Ca to the molten metal in advance. The shape of the heat insulating container 30 is not limited to the cylindrical shape, and may be a shape suitable for the subsequent molding method. Further, instead of the heat insulating container, it may be directly charged into a ceramic injection sleeve. If the holding time in the heat insulating container 30 is less than 5 seconds, it is not easy to bring the temperature to a desired liquid phase ratio, and it is difficult to generate spherical primary crystals. On the other hand, the retention time is 6
If it exceeds 0 minutes, the formed spherical primary crystals and eutectic structure become coarse and the mechanical properties deteriorate. Therefore, the holding time is 5 seconds to 60
Minutes. In high-pressure casting, the liquid phase ratio immediately before molding is 20.
If it is less than%, the deformation resistance at the time of molding is high and it is not easy to obtain a molded product of good quality. If it exceeds 90%, a molded product having a uniform structure cannot be obtained. Therefore, as described above, the liquid phase ratio during molding is preferably 20% to 90%. Furthermore, the actual liquid phase rate is 30% to
When the content is 70%, a more homogeneous and high-quality molding material can be easily pressure-molded. In addition, A which is close to the eutectic composition
When forming an 1-Si alloy, when it is necessary to generate eutectic Si in the heat insulating container and reduce the liquid phase ratio to 80% or less, Na or Sr, which is an element for improving Si, is added. This is convenient for refining eutectic Si and improving ductility. The means for pressure molding is not limited to the high pressure casting method represented by the squeeze casting method and the die casting casting method, and various methods for pressure molding such as extrusion method and forging method are included.

The jig 20 for contacting the molten metal M is not limited in its material as long as it can lower the temperature of the molten metal, but copper, copper alloy, aluminum, aluminum having particularly high thermal conductivity is used. The jig 20 which is made of a metal such as an alloy and which is cooled and controlled so that it can be maintained at a certain temperature or lower is preferable because many crystal nuclei are generated. In addition,
When the molten metal M comes into contact with the jig 20, the metal becomes solid in the jig 2
It is effective to apply a non-metallic material to prevent sticking to zero. The coating method may be mechanical, chemical or physical.

It is possible to obtain a semi-molten alloy below the liquidus line containing a large number of crystal nuclei by bringing the molten metal M into contact with the jig 20. A semi-molten alloy below the liquidus line containing a large number of crystal nuclei without contact with a jig, using a molten metal having a superheat of less than 100 ° C. with respect to the liquidus line. In order to obtain the above, Ti and B are added to the aluminum alloy, and Sr, Si and Ca are added to the magnesium alloy. 0.005% Ti
If it is less than 0.3%, the effect of refining is small, and if it exceeds 0.30%, a coarse Ti compound is generated and the ductility decreases, so Ti is set to 0.005% to 0.30%. B, together with Ti, promotes miniaturization, but if it is less than 0.001%, the miniaturization effect is small, and if it is added in excess of 0.02%, no further effect can be expected. 0.001% to 0.02
%. If Sr is less than 0.005%, the refining effect is small, and even if added in excess of 0.1%, no further effect can be expected, so Sr is set to 0.005% to 0.1%. 0.01% to 0.005% to 0.1% Sr
By adding 1.5% of Si in combination, finer crystal grains can be obtained than by adding Sr alone. Ca is 0.0
If it is less than 5%, the refining effect is small, and if it is added in excess of 0.30%, no further effect can be expected, so Ca is set to 0.05% to 0.30%. When obtaining a fine spherical primary crystal without using the jig 20, it is necessary to set the superheat degree to the liquidus line to less than 100 ° C., because the alloy poured into the heat insulating container 30 having a heat insulating effect is used as a crystal nucleus. This is for making a liquid state having the above or a solid-liquid coexisting state having a crystal nucleus at a molding temperature or higher. If the temperature of the poured molten metal in the heat insulating container 30 is high, it takes too much time because the temperature drops to a predetermined liquid phase rate, resulting in poor efficiency. Further, it is inconvenient because the surface of the poured molten metal M is oxidized or burned. Table 1 shows the conditions of the semi-molten metal before forming and the quality of the forming material. The molding was performed by inserting a semi-molten metal into the sleeve as shown in FIG. 3 and then using a squeeze casting machine. The molding conditions are: pressure 950 kgf / cm ² , injection speed 1.5 m / s, product cavity shape 100 × 150 ×
10. The mold temperature was 230 ° C.

[0013]

[Table 1]

In Comparative Example 1, the jig 2 for contacting the molten metal M
Since the temperature of 0 is too high, the generation of crystal nuclei is small, and therefore fine spherical primary crystals cannot be obtained, and only coarse amorphous primary crystals as shown in FIG. 8 are obtained. In Comparative Example 2, since the casting temperature is too high, almost no crystal nuclei remain in the ceramic container 30, and thus the same phenomenon as in Comparative Example 1 is exhibited. In Comparative Example 3, since the retention time is long, the liquid phase ratio is small and the appearance is not good. The primary crystal size is also large. In Comparative Example 4, since the holding time in the ceramic container 30 is short and the liquid phase ratio is high, the segregation of components inside the molded product is large. In Comparative Example 5, since a metal container having a small heat insulating effect was used, the dendrite-like solidified layer formed on the inner wall of the heat insulating container 30 was mixed with the spherical primary crystal formed at the center of the container, which caused segregation including segregation. It shows a homogeneous structure. Comparative Example 6
Shows a phenomenon similar to Comparative Example 4 because the liquid phase ratio is high.
In Comparative Example 7, the jig 20 is not used, but since the alloy does not contain the refiner, the generation of crystal nuclei is small and the same phenomenon as in Comparative Example 1 is exhibited. On the other hand, Example 8 of the present invention
In No. 18, a homogeneous structure having fine spherical primary crystals of 150 μm or less as shown in FIG. 7 is obtained, and a molded product having a good appearance is obtained. In addition, Table 2 shows the results on the molded products with and without the removal of oxides. According to Table 2, Examples 23 to 26 of the present invention show better results than Comparative Examples 21 and 22. ing.

[0015]

[Table 2]

[0016]

As is apparent from the above description, in the method for forming a semi-molten metal according to the present invention, (1) an alloy in the liquid state having a liquidus temperature above the liquidus temperature having crystal nuclei or crystal nuclei By holding the alloy in a solid-liquid coexisting state at or above the molding temperature for 5 seconds to 60 minutes while cooling to a molding temperature exhibiting a predetermined liquid phase ratio in an insulating container having a heat insulating effect, or (2 ) Crystal nuclei are generated by contacting the surface of the jig whose temperature is lower than the melting point of the alloy with the molten alloy whose superheat degree is kept below 300 ° C. with respect to the liquidus temperature to form fine and spherical particles. Generated primary crystals in the liquid of the alloy, and the alloy in a semi-molten state having a predetermined liquid phase ratio is supplied to a molding die and pressure-molded to obtain a conventional mechanical stirring method, an electromagnetic wave. Simple, easy, and low cost regardless of the stirring method Molded body having a fine single spherical structure is obtained. Also, the degree of superheat with respect to the liquidus temperature is 10
A molten aluminum alloy or a molten magnesium alloy containing an element that promotes the formation of crystal nuclei maintained below 0 ° C is poured directly into a heat-insulating container without using a jig and cooled to a molding temperature at which a predetermined liquid phase rate is exhibited. By maintaining the temperature for 5 seconds to 60 minutes, fine and spheroidized primary crystals can be similarly generated. In addition, it was decided to remove the upper surface of the metal melt generated by touching the air interface before putting the metal melt thus obtained into the injection sleeve and injection-filling it into the mold cavity. A molded product free of impurities can be obtained.

[Brief description of drawings]

FIG. 1 is a process explanatory view showing a method for forming a semi-molten metal of a hypoeutectic aluminum alloy having a composition of at least the maximum solid solution limit.

FIG. 2 is a process explanatory view showing a method of forming a semi-molten metal of a magnesium alloy or an aluminum alloy having a maximum solid solution in-limit composition.

FIG. 3 is a process explanatory view from the formation of spherical primary crystals to the molding.

FIG. 4 is a schematic diagram of a metal structure in each step shown in FIG.

FIG. 5 is an equilibrium diagram of an Al—Si alloy, which is a typical aluminum alloy.

FIG. 6 is an equilibrium diagram of a Mg—Al alloy, which is a typical magnesium alloy.

FIG. 7 is a copy of a micrograph showing the metal structure of a molded article of the present invention.

FIG. 8 is a copy of a micrograph showing a metal structure of a molded product of a comparative example.

[Explanation of Codes] 10 Laddle 20 Cooling Jig 30 Insulating Container (Ceramic Container) 30A Ceramic Coating Metal Container 40 Injection Sleeve 50 Mold 50a Mold Cavity M Metal (Molten) W Oxide t Temperature T Time

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C22C 21/00 C22C 21/00 N 23/00 23/00

Claims (10)

[Claims] 1. An alloy in the liquid state having a liquidus temperature or higher having a crystal nucleus or in a solid-liquid coexisting state having a crystal nucleus or higher in a forming temperature is provided in a heat insulating container having a heat insulating effect in a predetermined amount. By holding for 5 seconds to 60 minutes while cooling to a molding temperature showing a liquid phase rate, fine primary crystals are crystallized in the alloy solution, and the alloy is supplied to a molding die and added. In the pressure molding process, the upper surface of the semi-molten metal held in the heat insulating container is removed by a metal or non-metal jig immediately after pouring to the molding temperature, and then the semi-molten metal is injected into the injection sleeve. A method for forming a semi-molten metal, which comprises inserting into a mold and press forming. 2. The method for producing crystal nuclei comprises contacting a molten alloy having a superheat degree of less than 300 ° C. with respect to a liquidus temperature with a surface of a jig having a temperature lower than a melting point of the alloy. The method for forming a semi-molten metal according to claim 1. 3. The jig to be brought into contact with the molten metal is a metal jig or a non-metal jig, a metal jig whose surface is coated with a non-metal material containing a semiconductor, or a composite non-metal material containing a semiconductor. The method for forming a semi-molten metal according to claim 2, wherein the jig is made of a metal, and the jig can be cooled from the inside or the outside of the jig. 4. The method for forming a semi-molten metal according to claim 1 or 2, wherein the crystal nuclei are generated by vibrating the molten alloy which comes into contact with either or both of the jig and the heat insulating container. . 5. The method for forming a semi-molten metal according to claim 1, wherein the alloy is an aluminum alloy having a composition within the maximum solid solution limit or a hypoeutectic aluminum alloy having a composition not less than the maximum solid solution limit. 6. The method for forming a semi-molten metal according to claim 1 or 2, wherein the alloy is a magnesium alloy having a maximum solid solubility in-limit composition. 7. An aluminum alloy containing 0.001% of B
The method for forming a semi-molten metal according to claim 5, wherein the aluminum alloy is an aluminum alloy to which 0.01 to 0.01% and 0.005 to 0.3% of Ti are added. 8. A magnesium alloy containing 0.005 of Sr.
% -0.1% added magnesium alloy, or Si 0.01% -1.5% and Sr 0.005% -0.
Magnesium alloy added with 1% or Ca 0.05
% -0.30% added magnesium alloy as claimed in claim 6. 9. The method for forming a semi-molten metal according to claim 7, wherein the molten aluminum alloy having a degree of superheat with respect to the liquidus temperature of less than 100 ° C. is poured directly into a heat insulating container without using a jig. 10. The degree of superheat with respect to the liquidus temperature is 100 ° C.
The method for forming a semi-molten metal according to claim 8, wherein the molten magnesium alloy held below the temperature is poured directly into a heat insulating container without using a jig.