KR102599762B1 - Die casting aluminium alloy with high electrical conductivity and manufacturing method for aluminium alloy casting using the same, and aluminium alloy casting manufactured therefrom - Google Patents

Abstract

The present invention relates to an aluminum die casting alloy with excellent electrical conductivity properties, a casting product using the same, and a manufacturing method thereof. More specifically, it relates to an aluminum die casting alloy having excellent electrical conductivity as well as high strength and high thermal conductivity, a casting product using the same, and a manufacturing method thereof. It's about.
The aluminum die casting alloy with excellent electrical conductivity characteristics according to the present invention contains 7 to 8% by weight of silicon (Si), 0.2 to 0.7% by weight of iron (Fe), 0.05 to 1.0% by weight of magnesium (Mg), and 0.05 to 0.2% by weight of manganese (Mn). It is characterized in that it contains 0.001 to 0.003% by weight of beryllium (Be), and the balance is aluminum (Al).

Description

Aluminum die casting alloy with excellent electrical conductivity properties, casting products using the same, and manufacturing method thereof

The present invention relates to an aluminum die casting alloy with excellent electrical conductivity properties, a casting product using the same, and a manufacturing method thereof. More specifically, it relates to an aluminum die casting alloy having excellent electrical conductivity as well as high strength and high thermal conductivity, a casting product using the same, and a manufacturing method thereof. It's about.

In general, aluminum (Al) is easy to cast, alloys well with other metals, has strong corrosion resistance in the atmosphere, and has excellent electrical and thermal conductivity, so it is widely used throughout industry.

Aluminum can generally be formed through plastic processing such as forging/extrusion/rolling, but electronic products and automobile parts are manufactured through die casting process rather than plastic processing because they must maintain precise dimensions.

Die casting is a method of manufacturing a casting identical to the mold by injecting aluminum melt into a mold machined into the shape of the product. It is widely used for parts such as electronic products, automobiles, and aircraft that require accurate dimensions and relatively complex designs.

Pure aluminum is not suitable for use in die casting due to strength and durability issues, so various alloy elements such as Si, Cu, and Fe are added to the aluminum base to improve physical and chemical properties, and recently, high performance of electronic products and automobile parts has been improved. Due to the weight reduction, efforts have been made to improve the thermal and electrical properties as well as the durability of aluminum alloys.

In this regard, domestic patent number 10-1133103 contains zinc (Zn), magnesium (Mg), copper (Cu), zirconium (Zr), and titanium (Ti), and excellent tensile strength can be obtained through precipitation hardening heat treatment. Aluminum alloys for die casting that can be used are presented.

In addition, Korean Patent Publication No. 10-2014-0034557 proposes a high thermal conductivity Al-Cu alloy for die casting in which copper, magnesium, and iron are added to an aluminum base.

Meanwhile, the electrical conductivity of pure aluminum is high, but when alloying elements are dissolved in aluminum, the dissolved alloying elements lower the electrical conductivity of the aluminum alloy.

Alloy elements create electric field non-uniformity within the aluminum crystal structure, and as a result, free electrons contributing to electrical conductivity are scattered by impurity atoms in the crystal, ultimately lowering the electrical conductivity of the aluminum alloy.

However, the prior art only focused on improving the strength and thermal conductivity of aluminum alloy and had limitations in failing to suggest combinations and composition ratios of alloys to achieve high electrical conductivity.

Domestic Registered Patent No. 10-1133103 Domestic Published Patent No. 10-2014-0034557

The purpose of the present invention to solve the above problems is to provide an aluminum die casting alloy with high strength and high thermal conductivity as well as excellent electrical conductivity, a casting using the same, and a method for manufacturing the same.

The aluminum die casting alloy with excellent electrical conductivity characteristics of the present invention to solve the above problems includes 7 to 8% by weight of silicon (Si), 0.2 to 0.7% by weight of iron (Fe), 0.05 to 1.0% by weight of magnesium (Mg), and manganese ( It contains 0.05 to 0.2% by weight of Mn), 0.001 to 0.003% by weight of beryllium (Be), and the balance is aluminum (Al).

To solve the above problems, a method of manufacturing a casting using an aluminum die casting alloy with excellent electrical conductivity characteristics includes 7 to 8% by weight of silicon (Si), 0.2 to 0.7% by weight of iron (Fe), and 0.05 to 1.0% by weight of magnesium (Mg). , a raw material preparation step (S100) of preparing an alloy for aluminum die casting containing 0.05 to 0.2% by weight of manganese (Mn), 0.001 to 0.003% by weight of beryllium (Be), and the balance aluminum (Al); and the alloy for aluminum die casting It includes a molding step (S200) of supplying the molten material to a die casting mold and forming it.

In the molding step (S200), the casting temperature is 680 to 750°C and the casting pressure is 70 to 80 MPa.

A casting using an aluminum die-casting alloy with excellent electrical conductivity characteristics of the present invention to solve the above problems is manufactured by a manufacturing method, and the manufactured casting is applied to electronic device parts or automobile parts.

As described above, according to the present invention, the aluminum die casting alloy with excellent electrical conductivity properties, the casting product using the same, and the manufacturing method thereof have the effect of having excellent electrical conductivity as well as high strength and high thermal conductivity.

Specific features and advantages of the present invention will be described in detail below with reference to the accompanying drawings. Prior to this, if it is determined that a detailed description of the functions and configuration related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

The present invention relates to an aluminum die casting alloy with excellent electrical conductivity properties, a casting product using the same, and a manufacturing method thereof. More specifically, it relates to an aluminum die casting alloy having excellent electrical conductivity as well as high strength and high thermal conductivity, a casting product using the same, and a manufacturing method thereof. It's about.

The aluminum die casting alloy with excellent electrical conductivity characteristics of the present invention contains 7 to 8% by weight of silicon (Si), 0.2 to 0.7% by weight of iron (Fe), 0.05 to 1.0% by weight of magnesium (Mg), and 0.05 to 0.2% by weight of manganese (Mn). %, 0.001 to 0.003 wt% of beryllium (Be), the balance aluminum (Al) and other inevitable impurities.

The role of the alloy composition added to the aluminum alloy and the reason for limiting the composition are explained as follows.

Silicone (Si) is used to improve fluidity, thin molding, reduce shrinkage, and improve heat resistance, and may be added in an amount of 7.0 to 8.0% by weight.

Iron (Fe) is added to prevent alloy sticking and improve strength, and is added in an amount of 0.2 to 0.7% by weight. If added in less than 0.2% by weight, the effect of preventing sticking and improving strength is minimal, and if added in excess of 0.7% by weight, corrosion resistance decreases and precipitates are generated, so it is preferable not to deviate from the above addition amount.

Magnesium (Mg) improves strength and corrosion resistance by quickly growing an oxide layer (MgO) on the surface of the product, contributing to strength improvement. Magnesium, if added in excessive amounts, reduces fluidity, making it difficult to form products with complex shapes, and oxidation may occur, so in the present invention, it was added in an amount of 0.05 to 1.0% by weight based on the total weight.

Manganese (Mn) is an alloy element that contributes to the corrosion resistance of aluminum alloys. It is finely distributed on the base of aluminum and has the function of increasing the potential of aluminum. As a result, its contribution to corrosion resistance increases depending on the content, and at the same time, it has a positive influence on improving strength. In the present invention, 0.05 to 0.2% by weight of the total weight was added.

Beryllium (Be) plays a role in significantly reducing oxidation and discoloration of products caused by magnesium, and was added in an amount of 0.001 to 0.003% by weight in the present invention.

Except for the above-mentioned silicon, iron, magnesium, manganese, and beryllium, the remainder consists of aluminum and other inevitable impurities.

The impurity is any one of copper (Cu), zinc (Zn), nickel (Ni), tin (Sn), lead (Pb), titanium (Ti), or a combination thereof, and is contained in an amount of 0.1% by weight or less.

The aluminum die casting alloy with excellent electrical conductivity characteristics of the present invention has a tensile strength of 250 to 350 MPa, a yield strength of 160 to 200 MPa, an elongation of 3 to 10%, a thermal diffusivity of 55 to 70 ㎟/s, a thermal conductivity of 130 to 170 W/m.K, Electrical conductivity satisfies 30 to 40% IACS (International Annealed Copper Standard) or one or more combinations thereof.

Hereinafter, a method of manufacturing a cast product using an aluminum die casting alloy with excellent electrical conductivity characteristics according to the present invention will be described.

The method of manufacturing a casting using an aluminum die-casting alloy with excellent electrical conductivity characteristics according to the present invention includes a raw material preparation step (S100) of preparing an alloy for aluminum die-casting and supplying the melt obtained by melting the aluminum die-casting alloy to a die-casting mold. Includes a forming step (S200).

In the raw material preparation step (S100), 7 to 8% by weight of silicon (Si), 0.2 to 0.7% by weight of iron (Fe), 0.05 to 1.0% by weight of magnesium (Mg), 0.05 to 0.2% by weight of manganese (Mn), and beryllium (Be) ) Prepare an alloy for aluminum die casting containing 0.001 to 0.003% by weight, the balance being aluminum (Al).

The aluminum die casting alloy may contain other unavoidable impurities in addition to the raw materials described above, and the impurities include copper (Cu), zinc (Zn), nickel (Ni), tin (Sn), lead (Pb), and titanium (Ti). ) or any combination thereof, and may be included in an amount of 0.1% by weight or less.

In the forming step (S200), the aluminum die casting alloy is melted and the melt is supplied to a die casting mold for forming.

After the remaining weight of aluminum (Al) is completely dissolved by heating to 750 to 800°C, the aluminum melt is heated to 820 to 880°C, and then 7 to 8% by weight of silicon (Si) is added and the temperature is raised to 900 to 950°C. .

Thereafter, 0.2 to 0.7% by weight of iron (Fe), 0.05 to 0.2% by weight of manganese (Mn), and 0.001 to 0.003% by weight of beryllium (Be) were sequentially added and dissolved for 3 to 6 hours, and then reduced to 650 to 700 ° C. After that, 0.05 to 1.0% by weight of magnesium (Mg) is added to prepare an alloy composition for aluminum die casting.

Thereafter, in order to remove trace impurities such as oxides, carbides, and intermetallic compounds contained in the aluminum die casting alloy composition, an inert gas such as nitrogen or argon is injected to float the impurities, and then the floated impurities are filtered and removed. It may further include.

The casting temperature of the prepared alloy composition for aluminum die casting can be controlled to 650 to 750°C, and the casting pressure can be controlled to 70 to 80 MPa. Preferably, the casting pressure is controlled to 75 MPa to complete the casting.

A casting using an aluminum die casting alloy with excellent electrical conductivity characteristics of the present invention to solve the above problems is manufactured by the casting manufacturing method, and has a tensile strength of 250 to 350 MPa, a yield strength of 160 to 200 MPa, an elongation of 3 to 10%, Thermal diffusivity of 55 to 70 ㎟/s, thermal conductivity of 130 to 170 W/m.K, electrical conductivity of 30 to 40% satisfies one or more of IACS (International Annealed Copper Standard) or a combination thereof, and the manufactured casting is suitable for electronic devices. Applies to parts or automobile parts.

Hereinafter, the present invention will be described in detail below with reference to a preferred embodiment. However, the following examples are intended to specifically illustrate the present invention and are not limited thereto.

Comparative Examples 1 to 10 and Examples 1 to 10 were prepared by varying the composition ratio of the aluminum alloy composition as shown in Table 1 below. Among them, Comparative Example 1 is ALDC12, one of the commercial Al-Si alloys.

division Chemical Composition(%) Si Fe Mg Mn Be Cu Zn Ni Sn Pb Ti Comparative Example 1 12.0 0.8 0.2 0.1 - 3.0 0.7 0.3 0.1 0.1 0.1 Comparative Example 2 6.0 0.5 0.5 0.1 0.003 0.1↓ Comparative Example 3 8.5 0.5 0.5 0.1 0.003 0.1↓ Comparative Example 4 7.5 0.1 0.5 0.1 0.003 0.1↓ Comparative Example 5 7.5 0.8 0.5 0.1 0.003 0.1↓ Comparative Example 6 7.5 0.5 0.04 0.1 0.003 0.1↓ Comparative Example 7 7.5 0.5 1.2 0.1 0.003 0.1↓ Comparative Example 8 7.5 0.5 0.5 0.03 0.003 0.1↓ Comparative Example 9 7.5 0.5 0.5 0.25 0.003 0.1↓ Comparative Example 10 7.5 0.5 0.5 0.1 - 0.1↓ Comparative Example 11 7.5 0.5 0.5 0.1 0.004 0.1↓ Example 1 7.0 0.5 0.05 0.05 0.003 0.1↓ Example 2 7.5 0.5 0.5 0.1 0.003 0.1↓ Example 3 8.0 0.5 1.0 0.2 0.003 0.1↓ Example 4 7.5 0.2 0.5 0.1 0.003 0.1↓ Example 5 7.5 0.7 0.5 0.1 0.003 0.1↓ Example 6 7.5 0.5 0.05 0.1 0.003 0.1↓ Example 7 7.5 0.5 One 0.1 0.003 0.1↓ Example 8 7.5 0.5 0.5 0.05 0.003 0.1↓ Example 9 7.5 0.5 0.5 0.2 0.003 0.1↓ Example 10 7.5 0.5 0.5 0.1 0.001 0.1↓

The test piece was produced under the conditions shown in Table 2 below.

Unit: mm division Marking distance
(G) width
(w) thickness
(T) Shoulder
Radius (R) test piece
Total length (L) parallel part
Length (A) Bite part
Width (C) Subsize
(Plate) 25 6.25 3.05 6 100 or more 32 10

<Tensile strength measurement experiment>

The tensile strength, yield strength, and elongation of the test specimen were measured using a universal testing machine (Instron 5982), and Table 3 below shows the results.

tensile strength
(MPa) yield strength
(MPa) elongation
(%) Comparative Example 1 220 150 3 Comparative Example 2 190 127 7 Comparative Example 3 221 154 3 Comparative Example 4 223 155 5 Comparative Example 5 218 147 2 Comparative Example 6 183 122 6 Comparative Example 7 250 156 2 Comparative Example 8 211 133 4 Comparative Example 9 244 166 3 Comparative Example 10 182 123 3 Comparative Example 11 184 127 2 Example 1 275 160 8 Example 2 290 175 5 Example 3 300 185 3 Example 4 295 179 4 Example 5 270 163 3 Example 6 255 160 6 Example 7 310 190 3 Example 8 318 187 5 Example 9 323 190 3 Example 10 287 172 5

As a result, the tensile strength and yield strength of the examples were measured to be significantly higher than those of the comparative examples, and the target tensile strength of 250 MPa or more, yield strength of 160 MPa or more, and elongation of 3% or more were satisfied.

<Thermal and electrical properties measurement experiment>

importance
(g/㎤) specific heat
(J/g/K) thermal diffusivity
(㎟/s) thermal conductivity
(W/mk) electrical conductivity
(%IACS) Comparative Example 1 2.742 0.963 48.276 96.2 22.4 Comparative Example 2 2.675 0.839 56.562 126.94 29.1 Comparative Example 3 2.627 0.873 52.214 119.75 23.6 Comparative Example 4 2.648 0.852 57.213 129.08 28.6 Comparative Example 5 2.687 0.881 48.838 115.61 23.3 Comparative Example 6 2.642 0.882 55.483 129.29 28.7 Comparative Example 7 2.617 0.891 49.146 114.60 21.8 Comparative Example 8 2.628 0.859 56.328 127.16 29.3 Comparative Example 9 2.648 0.886 48.232 113.16 21.2 Comparative Example 10 2.642 0.923 49.223 120.03 27.4 Comparative Example 11 2.643 0.911 48.798 117.49 26.2 Example 1 2.693 0.904 66.352 161.53 34.2 Example 2 2.651 0.884 62.995 147.62 32.4 Example 3 2.645 0.869 59.631 137.06 31.7 Example 4 2.656 0.896 65.756 156.48 33.8 Example 5 2.694 0.876 59.524 140.47 32.7 Example 6 2.623 0.888 63.487 147.87 33.1 Example 7 2.587 0.871 62.127 139.98 31.5 Example 8 2.641 0.87 66.477 154.61 33.4 Example 9 2.684 0.894 58.234 135.93 30.8 Example 10 2.652 0.889 63.468 149.63 32.7

As a result, the thermal diffusivity, thermal conductivity, and electrical conductivity of Examples 1 to 10 were measured to be excellent compared to Comparative Examples 1 to 11, and the target thermal diffusivity of 55 mm2/s or more, thermal conductivity of 130 W/m.K or more, and electrical conductivity were measured. More than 30% IACS was satisfied.

As described above, the present invention has been described with a focus on preferred embodiments with reference to the accompanying drawings, but within the scope of those skilled in the art in the technical field to which the present invention pertains without departing from the technical spirit and scope described in the claims of the present invention. The present invention can be implemented with various modifications or modifications. Accordingly, the scope of the present invention should be construed by the appended claims to include examples of many such modifications.

Claims (5)

Silicon (Si) 7 to 8% by weight, iron (Fe) 0.2 to 0.7% by weight, magnesium (Mg) 0.05 to 1.0% by weight, manganese (Mn) 0.05 to 0.2% by weight, beryllium (Be) 0.001 to 0.003% by weight, Contains residual aluminum (Al) and other inevitable impurities,
Tensile strength of 250 to 350 MPa, yield strength of 160 to 200 MPa, elongation of 3 to 10%, thermal diffusivity of 55 to 70 ㎟/s, thermal conductivity of 130 to 170 W/mK, and electrical conductivity of 30 to 40%IACS (International Annealed Copper) Characterized by (Standard)
Aluminum die-casting alloy with excellent electrical conductivity properties.
Silicon (Si) 7 to 8% by weight, iron (Fe) 0.2 to 0.7% by weight, magnesium (Mg) 0.05 to 1.0% by weight, manganese (Mn) 0.05 to 0.2% by weight, beryllium (Be) 0.001 to 0.003% by weight, A raw material preparation step (S100) of preparing an alloy for aluminum die casting containing the remaining aluminum (Al) and other inevitable impurities;
It includes a forming step (S200) of supplying the molten aluminum die casting alloy to a die casting mold,
The alloy for aluminum die casting has a tensile strength of 250 to 350 MPa, a yield strength of 160 to 200 MPa, an elongation of 3 to 10%, a thermal diffusivity of 55 to 70 mm2/s, a thermal conductivity of 130 to 170 W/mK, and an electrical conductivity of 30 to 40. Characterized by %IACS (International Annealed Copper Standard)
A method of manufacturing castings using aluminum die casting alloy with excellent electrical conductivity characteristics.
According to clause 2,
In the forming step (S200)
The casting temperature is 680 to 750°C and the casting pressure is 70 to 80 MPa.
A method of manufacturing castings using aluminum die casting alloy with excellent electrical conductivity characteristics.
A casting product manufactured by the method for manufacturing a casting product using an aluminum die casting alloy with excellent electrical conductivity characteristics according to any one of claims 2 or 3.
According to clause 4,
The casting product manufactured above is
Characterized by being applied to electronic device parts or automobile parts
A casting product manufactured by a casting manufacturing method using an aluminum die casting alloy with excellent electrical conductivity characteristics.