KR101133775B1 - Magnesium mother alloy, manufacturing method thereof, Metal alloy using the same, and Metal alloy manufacturing method thereof - Google Patents

Abstract

The present invention relates to a magnesium mother alloy, a method for manufacturing the same, a metal alloy using the same, and a method for manufacturing the same. The technical problem to be solved is to provide a magnesium mother alloy with improved oxidation characteristics and ignition characteristics, and a method for manufacturing the same. It is to provide a metal alloy suitable for design purposes and a manufacturing method thereof at low cost.

To this end, the present invention provides a magnesium mother alloy comprising a plurality of magnesium crystals and scandium compounds dissolved in the magnesium crystals or scandium compounds present in the grain boundary as the exterior, not the interior of the magnesium crystals. In addition, the present invention provides a metal alloy suitable for design purposes and a manufacturing method thereof at low cost by adding a magnesium mother alloy having scandium as described above to a magnesium alloy or an aluminum alloy.

Description

Magnesium mother alloy, manufacturing method thereof, metal alloy using the same, and method for manufacturing the same

The present invention relates to a magnesium mother alloy, a method for producing the same, a metal alloy using the same, and a method for producing the same.

Currently, ultra-hard aluminum alloys (for example, 2000 series, 5000 series, 6000 series, 7000 series, etc.) use scandium (Sc) as an additive element to improve alloy characteristics such as hardness, corrosion resistance, and weldability. Is being studied. In this way, aluminum alloys with added scandium (Sc) are used for military applications (eg, combat vehicle reinforcements, rifle bodies, etc.) that require weldability and fatigue resistance, or for civilian (high speed rail vehicles, electric vehicles requiring high hardness and weldability). Parts).

However, such a scandium (Sc) is a rare earth, and only a small amount is present on the earth, and since it is difficult to separate from minerals, there is a disadvantage that it is very expensive.

Therefore, a method of adding low cost scandium oxide (Sc ₂ O ₃ ) to an aluminum alloy is contemplated.

However, when scandium oxide (Sc ₂ O ₃ ) is directly added to aluminum, there is a problem that the characteristics of various alloys such as hardness, corrosion resistance and weldability are degraded due to the oxide of scandium.

The present invention is to overcome the above-mentioned conventional problems, an object of the present invention is to provide a magnesium mother alloy with improved oxidation characteristics and ignition characteristics and a method for producing the same.

It is another object of the present invention to provide a metal alloy and a method for producing the same, which are suitable for design purposes at low cost and do not degrade alloy properties such as hardness, corrosion resistance and welding properties.

In order to achieve the above object, the magnesium mother alloy according to the present invention comprises a plurality of magnesium crystal grains; And scandium (Sc) dissolved in the magnesium crystal grains.

The scandium (Sc) may be present in 0.0001 to 30 parts by weight based on 100 parts by weight of magnesium.

In addition, in order to achieve the above object, the magnesium mother alloy according to the present invention comprises a plurality of magnesium-aluminum crystal grains having a grain boundary; And a scandium compound crystallized at the grain boundary as an exterior instead of the interior of the magnesium-aluminum crystal grain.

The scandium compound may be Al ₂ Sc, AlSc or Al ₃ Sc.

Scandium (Sc) in the scandium compound may be present in 0.0001 to 30 parts by weight based on 100 parts by weight of magnesium-aluminum.

In addition, in order to achieve the above object, a method for preparing a magnesium mother alloy according to the present invention includes the steps of forming a magnesium molten metal by melting magnesium in a crucible and dissolving it at a temperature of 600 to 800 ° C .; A scandium oxide addition step of adding scandium oxide (Sc ₂ O ₃ ) to the magnesium molten metal; Stirring the molten magnesium for 1 to 400 minutes; Casting the molten magnesium into a mold at room temperature to 400 ° C. for casting; And a cooling step of cooling the cast magnesium.

In the magnesium molten metal forming step, the magnesium may be pure magnesium or magnesium-aluminum.

Scandium oxide (Sc ₂ O ₃ ) added in the scandium oxide addition step may be 0.0001 to 30 parts by weight based on 100 parts by weight of pure magnesium or magnesium-aluminum.

In addition, in order to achieve the above object, the metal alloy according to the present invention comprises a plurality of metal grains having a grain boundary; And a scandium compound present in the grain boundary, including scandium (Sc) dissolved in the metal grains or outside the metal grains.

The metal is AZ91D, AM20, AM30, AM50, AM60, AZ31, AZ61, AZ80, AS41, AS31, AS21X, AE42, AE44, AX51, AX52, AJ50X, AJ52X, AJ62X, MRI153, MRI230, AM-HP2, Mg-Al , Mg-Al-Re, Mg-Al-Sn, Mg-Zn-Sn, Mg-Si and Mg-Zn-Y can be any one.

The metals are 1000 series, 2000 series, 3000 series, 4000 series, 5000 series, 6000 series, 7000 series and 8000 series of wrought aluminum or 100 series, 200 series, 300 series, 400 series, 500 series and 700 It may be any one selected from series casting aluminum.

The scandium compound may be Al ₂ Sc, AlSc or Al ₃ Sc.

Scandium (Sc) in the solid solution of scandium (Sc) or the scandium compound in the metal grains may be present in 0.0001 to 30 parts by weight based on 100 parts by weight of the metal.

In addition, the method for producing a metal alloy according to the present invention to achieve the above object is a metal molten metal forming step of forming a molten metal; Adding a magnesium master alloy to the magnesium molten alloy having a solid solution of scandium or a scandium compound in the molten metal; A stirring step of stirring the molten metal for 1 to 400 minutes; A casting step of casting the molten metal into a mold at room temperature to 400 ° C; And a cooling step of cooling the cast metal.

The magnesium master alloy having scandium used in the magnesium master alloy addition step may be added in an amount of 0.0001 to 30 parts by weight based on 100 parts by weight of the metal.

The magnesium mother alloy having scandium used in the magnesium mother alloy addition step may be prepared by adding 0.0001 to 30 parts by weight of scandium oxide (Sc ₂ O ₃ ) based on 100 parts by weight of pure magnesium.

The magnesium mother alloy having scandium used in the magnesium mother alloy addition step may be prepared by adding 0.0001 to 30 parts by weight of scandium oxide (Sc ₂ O ₃ ) based on 100 parts by weight of magnesium-aluminum.

The magnesium master alloy having scandium used in the magnesium master alloy addition step is prepared by adding 0.0001-30 parts by weight of scandium oxide (Sc ₂ O ₃ ) to 100 parts by weight of pure magnesium, and 100 parts by weight of magnesium-aluminum Scandium oxide (Sc ₂ O ₃ ) may be prepared by adding 0.0001 to 30 parts by weight with respect to.

The molten metal is AZ91D, AM20, AM30, AM50, AM60, AZ31, AZ61, AZ80, AS41, AS31, AS21X, AE42, AE44, AX51, AX52, AJ50X, AJ52X, AJ62X, MRI153, MRI230, AM-HP2, Mg- Al, Mg-Al-Re, Mg-Al-Sn, Mg-Zn-Sn, Mg-Si and Mg-Zn-Y may be formed of any one.

The molten metal is 1000 series, 2000 series, 3000 series, 4000 series, 5000 series, 6000 series, 7000 series and 8000 series plastic processing (Wrought) aluminum or 100 series, 200 series, 300 series, 400 series, 500 series and 700 It may be formed of any one selected from the group casting aluminum.

As described above, in the present invention, scandium oxide is added to the magnesium mother alloy, so that the oxidation characteristics and the ignition characteristics of the magnesium mother alloy are improved. In addition, the present invention is a magnesium alloy having a scandium as described above is added to a metal alloy such as magnesium alloy or aluminum alloy, the metal alloy can be produced at low cost, and also the hardness characteristics, corrosion resistance and welding properties of the metal alloy Alloy characteristics such as do not deteriorate.

In addition, in the present invention, two types of mother alloys (a magnesium mother alloy including scandium (Sc) dissolved in grains and a magnesium mother alloy in which scandium is crystallized) are manufactured, thereby making it known to use and purpose. Fit metal alloys can be produced. For example, if a metal alloy in the form of scandium solid solution is required, a magnesium mother alloy in which scandium is dissolved in the grains may be used. In addition, when a scandium-defined metal alloy is required, a magnesium master alloy in which scandium is crystallized may be used. Of course, a metal alloy may be prepared by adding both a magnesium mother alloy including solid solution scandium (Sc) and a magnesium mother alloy in which scandium is crystallized. Therefore, according to the present invention, a metal alloy suitable for use or purpose can be produced by various methods.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art can easily carry out the present invention.

1 is a flowchart illustrating a method of manufacturing a magnesium mother alloy according to the present invention.

As shown in FIG. 1, the method for preparing a magnesium master alloy according to the present invention includes a molten magnesium forming step (S1), an additive addition step (S2), a stirring step (S3), a casting step (S4), and a cooling step (S5). It includes.

In the magnesium molten metal forming step (S1), the magnesium is placed in a crucible and heated to 600 to 800 ° C. The magnesium in the crucible is then melted to form a magnesium molten metal. Here, when the temperature is less than 600 ℃, it is difficult to form a magnesium molten metal, when the temperature exceeds 800 ℃ there is a risk of ignition of magnesium molten metal.

In addition, a small amount of protective gas may be additionally provided to prevent ignition of the magnesium molten metal. The protective gas is a conventional SF ₆ , Ignition of the magnesium can be suppressed by using SO ₂ , CO ₂ , HFC-134a, Novec ™ 612, an inert gas and its equivalents, and also a mixed gas thereof. However, in the present invention, such a protective gas is not necessarily required and may not be provided.

In addition, the magnesium used in the magnesium molten metal forming step may be any one selected from pure magnesium, magnesium-aluminum, and equivalents thereof.

In the additive addition step (S2), an additive in powder form is added to the magnesium molten metal.

Here, the additive used in the additive addition step may be any one selected from inexpensive scandium oxide (Sc ₂ O ₃ ) and equivalents thereof, not expensive pure scandium (pure Sc). These additives serve to reduce the oxidation power of the magnesium master alloy and to increase the ignition temperature, thereby significantly reducing the required amount of the protective gas.

The additive used in the additive addition step may be added 0.0001 to 30 parts by weight based on 100 parts by weight of the magnesium mother alloy. When the additive is less than 0.0001 parts by weight, the effect by the additive (hardness increase, oxidation decrease, ignition temperature increase and protective gas decrease) may be small. In addition, when the additive exceeds 30 parts by weight, the original magnesium or magnesium alloy may not appear.

In addition, the additive used in the additive addition step may have a size of 0.1 ~ 500㎛. The size of the additives less than 0.1 μm is difficult and expensive to make in reality. In addition, when the size of the additive exceeds 500㎛ the additive may not react with the magnesium molten metal.

In the stirring step (S3), the magnesium molten metal is stirred for 1 to 400 minutes.

If the stirring time is less than 1 minute, the additives are not sufficiently mixed in the molten magnesium, and if the stirring time exceeds 400 minutes, the stirring time of the magnesium molten metal may be unnecessarily longer.

Here, the additive added to the molten magnesium does not exist in the form of an oxide. For example, when scandium oxide (Sc ₂ O ₃ ) is added as an additive to the molten magnesium, it is not present in the form of scandium oxide (Sc ₂ O ₃ ). That is, the scandium oxide (Sc ₂ O ₃ ) is reduced and reacts with the elements in the molten metal and scandium is dissolved in crystal grains to exist in the form of an alloy or crystallized to exist in the form of a compound. do.

Since scandium oxide (Sc ₂ O ₃ ) is usually thermodynamically more stable than magnesium, it is expected that scandium oxide (Sc ₂ O ₃ ) will not be reduced in the magnesium molten metal. However, experiments by the inventors have shown that scandium oxide (Sc ₂ O ₃ ) is reduced in magnesium molten metal. Reduction mechanisms have not yet been identified, and therefore, studies to identify the reduction mechanisms are ongoing by the inventors.

When scandium oxide (Sc ₂ O ₃ ) is substantially added to pure magnesium, scandium (Sc) is dissolved in pure magnesium. That is, scandium forms an alloy element with magnesium. In addition, when scandium oxide (Sc ₂ O ₃ ) is added to magnesium-aluminum, a scandium compound is crystallized at the grain boundary of magnesium-aluminum. That is, scandium does not form an alloying element with magnesium, but forms a scandium compound. Here, the scandium compound is usually in the form of Al ₂ Sc, AlSc or Al ₃ Sc.

Of course, the remaining elements (O ₂ ) constituting the additive are all suspended on the surface of the magnesium molten metal, which can be removed by manual or automatic equipment.

In the casting step S4, the magnesium molten metal is cast in a mold at room temperature (for example, 25 ° C) to 400 ° C.

Herein, the mold may use any one selected from a mold, a ceramic mold, a graphite mold, and an equivalent thereof. In addition, the casting method can be gravity casting, continuous casting and the equivalent method. However, the type of the mold and the method of casting are not limited here.

In the cooling step S5, after cooling the mold to room temperature, magnesium or magnesium-aluminum (eg, ingot) is taken out of the mold.

Here, the magnesium mother alloy prepared by the above method will include a plurality of magnesium crystal grains having a grain boundary and scandium (Sc) dissolved in the magnesium crystal grains, as described below, but not the inside of the magnesium crystal grains. As, it may be made of a scandium compound present in the grain boundary.

FIG. 2 is a tissue photograph showing a state in which scandium oxide is added to pure magnesium and scandium is dissolved. In one example, the tissue photograph is obtained by adding 0.5% scandium oxide to pure magnesium.

As shown in FIG. 2, the magnesium master alloy 100 manufactured according to the present invention includes a plurality of magnesium grains 110 and scandium dissolved in the grains of magnesium 110. Herein, substantially the scandium is not distinguished from the magnesium grains 110. This is because scandium alloys with magnesium.

Thus, compared with pure magnesium, the hardness characteristic of the magnesium master alloy manufactured by adding scandium oxide is improved. In addition, the scandium does not change the original composition ratio of the magnesium mother alloy and also does not disappear during the treatment for recycling the magnesium mother alloy, thereby greatly improving the recyclability of the magnesium mother alloy. That is, for example, when the magnesium master alloy is recycled, it is not necessary to add scandium or scandium oxide.

In addition, the scandium oxide may be prepared by adding 0.0001 to 30 parts by weight of magnesium. In addition, the scandium oxide may have a size of 0.1 ~ 500㎛. The significance of this numerical range has already been described above.

3 is a tissue photograph showing a state in which scandium compound is crystallized by adding scandium oxide to magnesium-aluminum. For example, the tissue photograph is obtained by adding 0.5% scandium oxide to magnesium-aluminum (Mg-3Al).

As shown in FIG. 3, the magnesium master alloy 200 manufactured according to the present invention includes a plurality of magnesium-aluminum crystal grains 210 and a scandium compound 211.

The plurality of magnesium-aluminum crystal grains 210 have a grain boundary, and the scandium compound 211 is present at the grain boundary as the exterior, not the interior of the magnesium-aluminum grain 210. Here, the scandium compound 211 is in the form of Al ₂ Sc, AlSc or Al ₃ Sc. That is, the scandium does not alloy with magnesium.

In this way, the magnesium master alloy 200 will be described below, but the hardness characteristics are improved. In addition, scandium does not change the original composition ratio of the magnesium master alloy and does not disappear during the treatment for recycling the magnesium master alloy, thereby greatly improving the recyclability of the magnesium master alloy. For example, there is no need to add scandium or scandium oxide when recycling the magnesium master alloy.

In addition, the scandium compound 211 may be added in an amount of 0.0001 to 30 parts by weight to 100 parts by weight of magnesium-aluminum. In addition, the scandium compound 211 may have a size of 0.1 ~ 500㎛. The significance of this numerical range has already been described above.

On the other hand, such magnesium master alloys are flame retardant alloys, casting alloys, rough alloys, creep alloys, damping alloys, degradable bio alloys and powder metals. It can be used with at least one selected from powder metallurgy.

For example, the casting alloy may be formed by mixing scandium oxide in AZ91D, AM20, AM50, and AM60.

The root alloy may be formed by mixing scandium oxide in AZ31, AM30, AZ61, and AZ80.

The creep alloy may be formed by mixing scandium oxide with Mg-Al and Mg-Al-Re. In addition, the creep alloy may be formed by mixing scandium oxide with Mg-Al-Sn or Mg-Zn-Sn.

The damping alloy may be formed by mixing scandium oxide with pure Mg, Mg-Si, and SiCp / Mg.

The degradable bioalloy may be formed by mixing scandium oxide with pure Mg.

The powder metal waste may be formed by mixing scandium oxide with Mg-Zn- (Y).

Of course, in all the alloys, only scandium in which O ₂ is finally removed from scandium oxide is crystallized at the grain boundary or is dissolved in the grain boundary.

4 is a graph showing the results of hardness comparison between pure magnesium and pure magnesium added with scandium oxide according to the present invention. In Fig. 4, the X axis is pure magnesium and magnesium added with 0.5% scandium oxide, and the Y axis is hardness value (HR).

As shown in Figure 4 it can be seen that the hardness increases when the scandium oxide is added during the manufacturing process of the magnesium mother alloy. That is, the hardness of pure magnesium without the addition of scandium oxide is approximately HRF41, but the hardness of the magnesium mother alloy with addition of scandium oxide is increased to approximately HRF53.

5 is a graph showing the results of oxidation experiments between pure magnesium and magnesium base alloy to which scandium oxide was added according to the present invention. In FIG. 5, the X axis represents elapsed time (min), and the Y axis represents oxidation amount (%). The default value of the Y axis is set to 100.

As shown in FIG. 5, in the case of pure magnesium, oxidation is accelerated and the Y-axis value increases as time passes. However, it can be seen that in the case of magnesium alloy to which scandium oxide is added during the manufacturing process, the Y-axis value, that is, the amount of oxidation does not increase over time. That is, the magnesium master alloy according to the present invention is not oxidized over time, and thus is safe for various applications.

6 is a graph showing the results of ignition experiments between pure magnesium and magnesium master alloy to which scandium oxide was added according to the present invention. In Fig. 6, the X axis is pure magnesium and magnesium added with 0.5% scandium oxide, and the Y axis is the ignition temperature (° C).

As shown in FIG. 6, it can be seen that the firing temperature is increased in the case of the magnesium mother alloy to which scandium oxide is added during the manufacturing process. That is, the firing temperature of the pure magnesium without the scandium oxide is approximately 600 ℃, it can be seen that the firing temperature of the magnesium master alloy added with the scandium oxide is raised to approximately 700 ℃.

7 is a graph showing the results of hardness comparison between magnesium-aluminum alloy and magnesium-aluminum alloy to which scandium oxide is added according to the present invention. In FIG. 4, the X-axis is a magnesium-aluminum alloy and a magnesium-aluminum alloy to which 0.5% scandium oxide is added, and the Y-axis is hardness value (HR).

As shown in Figure 7, it can be seen that the hardness increases when the scandium oxide is added during the manufacturing process of magnesium-aluminum. That is, it can be seen that the hardness of the magnesium-aluminum alloy to which scandium oxide is not added is approximately HRF50, but the hardness of the magnesium-aluminum alloy to which scandium oxide is added is raised to approximately HRF68.

8 is a flowchart illustrating a method of manufacturing a metal alloy according to the present invention.

As shown in FIG. 8, the method of manufacturing a metal alloy according to the present invention includes forming a molten metal (S11), adding a magnesium mother alloy with scandium (S12), stirring (S13), casting (S14), and cooling. Step S15 is included.

In the molten metal forming step (S11), a magnesium alloy or an aluminum alloy is placed in a crucible and heated to 600 to 800 ° C. The metal in the crucible is then melted to form a molten metal. In this case, when the temperature is less than 600 ° C., the molten metal is less likely to be formed, and when the temperature exceeds 800 ° C., there is a risk that the metal molten metal is ignited.

Here, for example, the metal is AZ91D, AM20, AM30, AM50, AM60, AZ31, AZ61, AZ80, AS41, AS31, AS21X, AE42, AE44, AX51, AX52, AJ50X, AJ52X, AJ62X, MRI153, MRI230, AM-HP2 Mg-Al, Mg-Al-Re, Mg-Al-Sn, Mg-Zn-Sn, Mg-Si, Mg-Zn-Y may be any one magnesium alloy selected from.

In addition, the metal is 1000 series, 2000 series, 3000 series, 4000 series, 5000 series, 6000 series, 7000 series and 8000 series wrought aluminum or 100 series, 200 series, 300 series, 400 series, 500 series, It may be a metal alloy, characterized in that any one selected from 700 series casting aluminum.

Here, the aluminum alloy will be described in more detail. Aluminum alloys have been developed in various types according to their use, and the types of aluminum alloys are classified according to the standards of the Aluminum Association of America in almost every country today. Table 1 shows the composition of the main alloying elements by the alloy series in thousands, and adds another improved element to each alloy series to further subdivide the four-digit number and attach the alloy name.

[Table 1] Classification of aluminum according to alloy series

The first number indicates the alloy series representing the main alloy element as above, the second number indicates the base alloy as 0, and the improved alloy as the number 1 ~ 9. Attach. For example, 2xxx is a base alloy of Al-Cu series aluminum, 21xx ~ 29xx is an improvement of Al-Cu series base alloy, and 2Nxx is a new alloy developed outside the association standard. The third and fourth numbers indicate the purity of aluminum in the case of pure aluminum, and the alloy name of the Alcoa company used in the past for alloys. For example, in the case of pure aluminum, 1080 represents at least 99.80% Al and 1100 represents 99.00% Al.

The composition of the main work alloy is as shown in Table 2 below. The properties of each alloy vary greatly depending on the constituent metal and content as well as the processing method.

The main configuration of the aluminum alloy is shown in Table 2 below.

[Table 2] Main composition of aluminum alloy

In the magnesium master alloy adding step (S12), a magnesium mother alloy having scandium is added to the molten metal. Here, as described above, the molten metal is a magnesium alloy or an aluminum alloy, as described above.

Here, the magnesium master alloy added step is prepared by adding any one selected from low-cost scandium oxide (Sc ₂ O ₃ ) and equivalents thereof to magnesium or magnesium-aluminum compared to pure pure scandium (pure Sc). It may be. Since magnesium, magnesium-aluminum, and a method for producing the same have already been described above sufficiently, further description thereof will be omitted.

In this way, the present invention can solve various problems when the scandium oxide is added directly to the molten metal by adding magnesium or magnesium-aluminum alloy having scandium produced at low cost to the molten metal. For example, if scandium oxide (Sc ₂ O ₃ ) is directly added to aluminum, there is a problem of degrading the quality of the alloy as an oxide, but as in the present invention, magnesium or magnesium-aluminum containing scandium (Sc) is added to aluminum. By adding it, the quality of an alloy is not reduced. More specifically, the addition of scandium oxide (Sc ₂ O ₃ ) directly to aluminum reduces the alloy properties of hardness, corrosion resistance and welding properties, but it is already magnesium or magnesium containing scandium as in the present invention. When aluminum is added to aluminum, the alloy properties of hardness, corrosion resistance and welding properties are maintained.

Here, for example, the 5000 series metal alloy is stronger than the 3000 series metal alloy, is easy to form, and is more resistant to corrosion. It also has the advantage of being welded. In particular, alloy 5182 may be used on the lid of an aluminum can. In addition, 5005, 5083, and 5052, 5056, 5086 and variants can be widely used in electrical installations, various kitchen containers, metal plates, pressure vessels, radio transmission towers, welding structures, boats, and chemical storage. Insect screens, nails and fasteners can usually be made from 5000 series alloys. When magnesium or magnesium-aluminum, which already contains scandium, is added to the 5000 series of metal alloys having such characteristics, an aluminum alloy is obtained at low cost and in which hardness characteristics, corrosion resistance and weldability are not deteriorated. .

On the other hand, the additive used in the magnesium master alloy addition step may be added 0.0001 to 30 parts by weight based on 100 parts by weight of the metal. When the additive is less than 0.0001 parts by weight, the effect due to magnesium (hardness, corrosion resistance, weldability) may be small. In addition, when the additive is more than 30 parts by weight, the properties of the original metal alloy may not appear.

In addition, the size of the additive used in the magnesium master alloy addition step may be 0.1 ~ 500㎛. The size of the additives less than 0.1 μm is difficult and expensive to make in reality. In addition, when the size of the additive exceeds 500㎛ the magnesium may not react with the molten metal.

In addition, the additive used in the magnesium-alunium addition step may be added 0.0001 to 30 parts by weight based on 100 parts by weight of the metal alloy. When the additive is less than 0.0001 parts by weight, the effect due to magnesium (hardness, corrosion resistance, weldability) may be small. In addition, when the additive is more than 30 parts by weight, the properties of the original metal alloy may not appear.

In addition, the additive used in the magnesium-aluminum addition step may have a size of 0.1 ~ 500㎛. The size of the additives less than 0.1 μm is difficult and expensive to make in reality. In addition, when the size of the additive exceeds 500㎛ the magnesium-aluminum may not react with the molten metal.

In the stirring step (S13), the metal molten metal is stirred for 1 to 400 minutes.

If the stirring time is less than 1 minute, the additives are not sufficiently mixed in the molten metal, and if the stirring time exceeds 400 minutes, the stirring time of the molten metal may be unnecessarily longer.

Here, when the molten metal is aluminum, scandium in magnesium added to the molten aluminum is present as Al ₂ Sc, AlSc or Al ₃ Sc due to the high elemental affinity between aluminum and scandium.

In addition, in the stirring step as described above, the Al ₂ Sc, AlSc or Al ₃ Sc does not exist in the interior of the metal grains, it is present in the form of an intermetallic compound at the outside of the grains, that is, the grain boundary. That is, in this stirring step, the metal compound of Al ₂ Sc, AlSc or Al ₃ Sc is formed.

In the casting step S14, the molten metal is cast in a mold at room temperature (for example, 25 ° C) to 400 ° C.

Herein, the mold may use any one selected from a mold, a ceramic mold, a graphite mold, and an equivalent thereof. In addition, the casting method can be gravity casting, continuous casting and the equivalent method. However, the type of the mold and the method of casting are not limited here.

In the cooling step S5, the mold is cooled to room temperature, and then a metal alloy (eg, a metal alloy ingot) is taken out of the mold.

Here, the metal alloy prepared by the above method is a plurality of metal grains having a grain boundary, and the intermetallic compound (ie, Al ₂ Sc or AlSc or Al ₃ present in the grain boundary as the outside, not the inside of the metal grains) Sc). Of course, in some cases, for metals such as pure magnesium, scandium is in the form of a solid solution inside the metal grains.

In this way, the present invention provides various problems when the scandium oxide is directly added to the molten metal by adding a magnesium master alloy (magnesium with scandium or magnesium-aluminum with scandium) to the molten metal (magnesium alloy or aluminum alloy). Can be solved. For example, if scandium oxide (Sc ₂ O ₃ ) is directly added to aluminum, there is a problem of degrading the quality of the alloy as an oxide, but as in the present invention, magnesium or magnesium-aluminum containing scandium is added to aluminum to Aluminum alloys can be manufactured at low cost without compromising quality (strength, corrosion resistance, weldability, etc.).

Meanwhile, the strength test data of the aluminum alloy prepared by the above method is described in Table 3 below.

[Table 3] Strength test data of aluminum alloy

As shown in Table 3 above, when magnesium or magnesium-aluminum, in which scandium is already added, is added to the 7000 series aluminum alloy, the strength increases from 550-600 MPa to 650-700 MPa.

In addition, as shown in Table 3 above, when magnesium or magnesium-aluminum, in which scandium is already added, is added to the aluminum alloy of the series 5000, the strength increases from 350-400 MPa to 450-500 MPa. .

Thus, according to the metal alloy and the manufacturing method thereof according to the present invention, the magnesium master alloy having scandium is added to a metal alloy such as a magnesium alloy or an aluminum alloy, whereby the metal alloy is produced at low cost and the hardness of the metal alloy Alloy properties such as properties, corrosion resistance and welding properties are not degraded.

In addition, in the present invention, the magnesium alloy in which scandium is dissolved in the metal grains or the magnesium mother alloy in which scandium is crystallized at the grain boundary can be easily manufactured. For example, when a metal alloy in the form of scandium is dissolved, a magnesium mother alloy in which scandium is dissolved in the metal grains may be used. In addition, when a metal alloy of the scandium crystallized form is required, a magnesium mother alloy in which scandium is crystallized at the grain boundary may be used. Of course, the metal alloy may be prepared by adding a magnesium mother alloy in which scandium is dissolved in the metal grains or a magnesium mother alloy in which scandium is crystallized to the grain boundary.

What has been described above is just one embodiment for carrying out a magnesium mother alloy, a method for producing the same, a metal alloy using the same, and a method for producing the same according to the present invention, the present invention is not limited to the above embodiment, As claimed in the claims, any person having ordinary skill in the art without departing from the gist of the present invention will have the technical spirit of the present invention to the extent that various modifications can be made.

1 is a flowchart illustrating a method of manufacturing a magnesium mother alloy according to the present invention.

FIG. 2 is a tissue photograph showing a magnesium mother alloy in which scandium oxide is added to pure magnesium to form a scandium solution.

3 is a structure photograph showing a magnesium mother alloy in which scandium oxide is added to magnesium-aluminum to form scandium.

4 is a graph showing the results of hardness comparison between pure magnesium and magnesium master alloy to which scandium oxide is added according to the present invention.

5 is a graph showing the results of oxidation experiments between pure magnesium and magnesium master alloy added with scandium oxide according to the present invention.

6 is a graph showing the results of ignition experiments between pure magnesium and magnesium master alloy to which scandium oxide was added according to the present invention.

FIG. 7 is a graph showing the results of hardness comparison between pure magnesium and magnesium master alloy (magnesium-aluminum) to which scandium oxide is added according to the present invention.

8 is a flowchart illustrating a method of manufacturing a metal alloy according to the present invention.

Claims (20)

Multiple magnesium grains; And Including the scandium (Sc) dissolved in the inside of the magnesium crystals, The scandium (Sc) is a magnesium master alloy, characterized in that reduced from scandium oxide (Sc ₂ O ₃ ). The method of claim 1, Scandium (Sc) is Magnesium master alloy, characterized in that 0.0001 to 30 parts by weight based on 100 parts by weight of magnesium. Many magnesium-aluminum grains having grain boundaries; And A scandium compound crystallized in the grain boundary as an exterior instead of the interior of the magnesium-aluminum grain, The scandium compound is magnesium master alloy, characterized in that reduced from scandium oxide (Sc ₂ O ₃ ). The method of claim 3, wherein The scandium compound is magnesium master alloy, characterized in that Al ₂ Sc, AlSc or Al ₃ Sc. The method of claim 3, wherein Scandium (Sc) in the scandium compound is Magnesium master alloy, characterized in that 0.0001 to 30 parts by weight based on 100 parts by weight of magnesium-aluminum. A magnesium molten metal forming step of melting magnesium into a crucible and dissolving it at a temperature of 600 to 800 ° C. to form a molten magnesium; A scandium oxide addition step of adding scandium oxide (Sc ₂ O ₃ ) to the magnesium molten metal; Stirring the molten magnesium for 1 to 400 minutes; Casting the molten magnesium into a mold at room temperature to 400 ° C. for casting; And Method of producing a magnesium master alloy characterized in that it comprises a cooling step of cooling the cast magnesium. The method of claim 6, In the magnesium molten metal forming step The magnesium is a magnesium master alloy, characterized in that the pure magnesium or magnesium-aluminum. The method of claim 6, Scandium oxide (Sc ₂ O ₃ ) added in the scandium oxide addition step is Method for producing a magnesium master alloy, characterized in that 0.0001 to 30 parts by weight based on 100 parts by weight of pure magnesium or magnesium-aluminum. A plurality of metal grains having grain boundaries; And A scandium compound (Sc) dissolved in the metal grains, or a scandium compound present in the grain boundary as the outside of the metal grains; The scandium (Sc) or the scandium compound is metal alloy, characterized in that reduced from scandium oxide (Sc ₂ O ₃ ). The method of claim 9, The metal is AZ91D, AM20, AM30, AM50, AM60, AZ31, AZ61, AZ80, AS41, AS31, AS21X, AE42, AE44, AX51, AX52, AJ50X, AJ52X, AJ62X, MRI153, MRI230, AM-HP2, Mg-Al , Mg-Al-Re, Mg-Al-Sn, Mg-Zn-Sn, Mg-Si and Mg-Zn-Y metal alloy, characterized in that any one selected from. The method of claim 9, The metals are 1000 series, 2000 series, 3000 series, 4000 series, 5000 series, 6000 series, 7000 series and 8000 series of wrought aluminum or 100 series, 200 series, 300 series, 400 series, 500 series and 700 Metal alloy, characterized in that any one selected from the series (Casting) aluminum The method of claim 9, The scandium compound is Al ₂ Sc, AlSc or Al ₃ Sc characterized in that the metal alloy. The method of claim 9, Scandium (Sc) in the scandium (Sc) or the scandium compound dissolved in the metal crystal grains is Metal alloy, characterized in that 0.0001 to 30 parts by weight based on 100 parts by weight of the metal. A metal molten metal forming step of forming a metal molten metal; Adding a magnesium master alloy to the magnesium molten alloy having a solid solution of scandium or a scandium compound in the molten metal; A stirring step of stirring the molten metal for 1 to 400 minutes; A casting step of casting the molten metal into a mold at room temperature to 400 ° C; And A cooling step of cooling the cast metal, The magnesium master alloy having scandium used in the magnesium master alloy addition step may be prepared by adding 0.0001-30 parts by weight of scandium oxide (Sc ₂ O ₃ ) to 100 parts by weight of pure magnesium, It is prepared by adding 0.0001 to 30 parts by weight of scandium oxide (Sc ₂ O ₃ ) based on 100 parts by weight of magnesium-aluminum, It was prepared by adding 0.0001 to 30 parts by weight of scandium oxide (Sc ₂ O ₃ ) to 100 parts by weight of pure magnesium, and by adding 0.0001 to 30 parts by weight of scandium oxide (Sc ₂ O ₃ ) to 100 parts by weight of magnesium-aluminum. Method for producing a metal alloy characterized in that the production. delete delete delete delete 15. The method of claim 14, The molten metal is AZ91D, AM20, AM30, AM50, AM60, AZ31, AZ61, AZ80, AS41, AS31, AS21X, AE42, AE44, AX51, AX52, AJ50X, AJ52X, AJ62X, MRI153, MRI230, AM-HP2, Mg-Al, Mg- Method for producing a metal alloy, characterized in that formed of any one of Al-Re, Mg-Al-Sn, Mg-Zn-Sn, Mg-Si and Mg-Zn-Y. 15. The method of claim 14, The molten metal is For casting of 1000 series, 2000 series, 3000 series, 4000 series, 5000 series, 6000 series, 7000 series and 8000 series plastic processing (Wrought) aluminum or 100 series, 200 series, 300 series, 400 series, 500 series and 700 series Casting) A method for producing a metal alloy, characterized in that formed in any one of aluminum.

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