KR101780463B1 - Aluminium alloy composition for die casting - Google Patents

Abstract

The present invention relates to an aluminum alloy composition for die casting, more specifically, which comprises: 0.85-1.2 wt% of copper; 0.15-0.2 wt% of silicon; 0.08-0.1 wt% of magnesium; 0.08-0.12 wt% of zinc; 1.5-2.5 wt% of iron; and the remainder consisting of inevitable impurities and aluminum. As stated above, the aluminum alloy composition for die casting has excellent mechanical matter property and heat conductivity, and a phenomenon in which the composition is attached to a mold is restricted to improve efficiency of a die casting process.

Description

[0001] ALUMINUM ALLOY COMPOSITION FOR DIE CASTING [0002]

The present invention relates to an aluminum alloy composition for die casting, and more particularly to an aluminum alloy composition for die casting which exhibits excellent mechanical properties and thermal conductivity and inhibits the phenomenon of being adhered to a die to improve the efficiency of a die casting process.

Aluminum alloy is light and strong in strength, so it is widely used as a durable material. Especially, recently, it is widely used as a case of an electronic product such as an automobile part or a mobile phone. Normally, two methods are commonly used for manufacturing a product with aluminum.

First, a case is formed by press molding an aluminum plate, and an anodic oxide film is formed on the surface of the case, so that a casing having a surface of a beautiful color without damaging the surface portion even if used for a long time can be obtained. However, when a case is manufactured by press molding an aluminum plate, it is difficult to secure a space for a component to be mounted inside the case and to form a boss for rib and screw connection for reinforcement. In addition, since there is a shape that can not be formed by press working, there is a problem that the design of the case is limited.

Secondly, there is a die casting method. When a case is manufactured by the die casting method, it is easy to form a space for seating a component mounted inside the case, a boss for screw tightening and a rib for reinforcement of strength. There is an advantage to be able to do. However, conventionally, aluminum alloy for die casting has a relatively low mechanical strength and thermal conductivity, and the composition for aluminum alloy sticks to the die during the die casting process, which lowers the efficiency of the die casting process.

Korean Patent Registration No. 10-1274089 (2013.06.05) Korean Patent Registration No. 10-1308963 (2013.09.10)

It is an object of the present invention to provide an aluminum alloy composition for die casting which exhibits excellent mechanical properties and thermal conductivity and is suppressed from adhering to a mold to improve the efficiency of the die casting process.

In one embodiment, the content of this disclosure is a composition containing 0.85 to 1.2 wt.% Copper, 0.15 to 0.2 wt.% Silicon, 0.08 to 0.1 wt.% Magnesium, 0.08 to 0.12 wt.% Zinc, 1.5 to 2.5 wt.% Iron and unavoidable impurities And the remainder is made of aluminum.

Preferably, the copper may be contained in an amount of 0.9 to 1.0% by weight.

More preferably, the iron may be contained in an amount of 1.7 to 2.2% by weight.

The aluminum alloy composition for die casting as described above exhibits excellent mechanical properties and thermal conductivity, and exhibits an excellent effect of improving the efficiency of the die casting process by suppressing the phenomenon adhering to the mold.

Hereinafter, preferred embodiments of the present invention and physical properties of the respective components will be described in detail with reference to the accompanying drawings. However, the present invention is not limited thereto, And this does not mean that the technical idea and scope of the present invention are limited.

The disclosed aluminum alloy composition for die casting contains 0.85 to 1.2 wt% of copper, 0.15 to 0.2 wt% of silicon, 0.08 to 0.1 wt% of magnesium, 0.08 to 0.12 wt% of zinc, 1.5 to 2.7 wt% of iron and unavoidable impurities, Lt; / RTI >

The copper is contained in an amount of 0.85 to 1.2% by weight, and not only improves the strength and hardness of the disclosed aluminum alloy composition for die casting, but also improves the thermal conductivity and improves the efficiency of the die casting process.

If the content of copper is less than 0.85 wt%, the above effect is insignificant. If the content of copper exceeds 1.2 wt%, the corrosion resistance of the aluminum alloy composition for die casting is remarkably lowered.

At this time, it is more preferable that the content of copper is 0.9 to 1.0 wt% in consideration of improvement of thermal conductivity and corrosion resistance as described above.

The silicon is contained in an amount of 0.15 to 0.2 wt% and improves the casting performance in the die casting process because it improves the flowability and strength of the disclosed aluminum alloy composition for die casting. More specifically, the silicon is bonded to magnesium By aging, Mg ₂ Si precipitates and determines the mechanical properties. Residual silicon remaining after binding with magnesium (Mg) is precipitated singly to improve the mechanical properties and improve the fluidity of the melt.

Silicon is an element which improves the fluidity and strength of an aluminum alloy, and a large amount of silicon content is excellent in casting but becomes brittle due to the formation of magnesium silicate (Mg ₂ Si) phase and needle-like silicon phase, and 0.15 to 0.2 wt% If the content of silicon is less than 0.15% by weight, the effect of improving the strength of the aluminum alloy composition for die casting is insignificant. If the content of silicon exceeds 0.2% by weight, the aluminum alloy composition for die casting is too brittle And the mechanical properties are deteriorated.

The magnesium is contained in an amount of 0.08 to 0.1% by weight, and forms a precipitation phase of the aluminum alloy composition for die casting and serves to improve tensile strength and mechanical properties.

If the content of magnesium is less than 0.08% by weight, the effect is insignificant. When the content of magnesium exceeds 0.1% by weight, inclusions and physical properties are lowered due to oxidation and main composition is lowered. The elongation can be lowered.

The zinc is contained in an amount of 0.08 to 0.12% by weight and reacts with the magnesium to precipitate a zinc-magnesium-based strengthened phase. When the temperature is elevated, the ductility is increased to form a gathered structure in a material subjected to a predetermined processing It exhibits anisotropy in mechanical properties and prevents corrosion of products.

If the content of zinc is less than 0.08% by weight, the above-mentioned effect is insignificant. If the content of zinc exceeds 0.12% by weight, the strength of the aluminum alloy composition for die casting is excessively increased, which may lower the efficiency of the die casting process.

The iron contains 1.5 to 2.5% by weight of iron and improves the bonding force of components such as aluminum, copper, silicon, magnesium and zinc in the die casting process, thereby suppressing generation of sub-components.

If the content of iron is less than 1.5% by weight, the effect of preventing the formation of small particles is insignificant. If the content of iron exceeds 2.5% by weight, the effect of preventing the subdivision of the aluminum alloy composition is not significantly improved. The toughness is lowered, and the melting temperature is increased to lower the casting composition.

In addition, iron can contribute to the improvement of strength by increasing the density of the alloy, improving the demolding performance by reducing the tackiness, suppressing the coarsening of the recrystallized grains, and refining the crystal grains during casting. If it is added, not only the ductility is lowered but also the extrudability and the productivity are lowered.

In this case, it is more desirable that the content of iron is 1.7 to 2.2% by weight when considering the effect of preventing sub-fractionation, prevention of toughness reduction, and dissolution temperature.

Hereinafter, the method of manufacturing the aluminum alloy composition for die casting and the properties of the aluminum alloy composition for die casting manufactured through the method will be described with reference to examples.

≪ Example 1 >

After heating 96.64% of aluminum to a temperature of 950 ° C, 1.0% by weight of copper and 0.17% by weight of silicon were charged, and the mixture containing silicon was heated to a temperature of 1200 ° C. Then, 0.09% by weight of magnesium and 0.1% , Magnesium and zinc were heated to 1550 캜, and then 2.0% by weight of iron was added thereto. The mixture was cooled to room temperature to prepare an aluminum alloy composition for die casting.

The hardness of the aluminum alloy composition for die casting prepared in Example 1 was measured and shown in Table 1 below.

(Note that the hardness of the aluminum alloy composition for die casting was measured by Brinell hardness test after molding the aluminum alloy composition for die casting prepared in Example 1 to a thickness of 4.05 mm)

<Table 1>

As shown in Table 1 above, it can be seen that the aluminum alloy composition for die casting produced through the disclosed Example 1 exhibits excellent mechanical properties.

Accordingly, the disclosed aluminum alloy composition for die casting exhibits excellent mechanical properties and thermal conductivity, and exhibits an effect of suppressing the phenomenon of adhering to the mold, thereby improving the efficiency of the die casting process.

Claims (3)

Characterized in that it contains 0.85 to 1.2% by weight of copper, 0.15 to 0.2% by weight of silicon, 0.08 to 0.1% by weight of magnesium, 0.08 to 0.12% by weight of zinc, 1.5 to 2.5% by weight of iron, and inevitable impurities, &Lt; / RTI &gt;
The method according to claim 1,
Wherein the copper is contained in an amount of 0.9 to 1.0% by weight.
The method according to claim 1,
Wherein the iron is contained in an amount of 1.7 to 2.2% by weight.