KR20180115983A - Magnesium alloy with and high thermal diffusivity and strength - Google Patents

Abstract

The present invention relates to a magnesium alloy, manufacturing vehicles or electronic devices, which are light and require thermal diffusion and strength. The magnesium alloy comprises: 0.1-4.0 wt% of aluminium (AI); 0.5-2.0 wt% of copper (Cu); 1.0-6.0 wt% of zinc (Zn); 0.1 wt% or less of manganese (Mn); 0.1 wt% or less of nickel (Ni); 0.1 wt% or less of silicon (Si); and the remainder consisting of magnesium (Mg) and other unavoidable impurities. Accordingly, the magnesium alloy can increase thermal diffusion and strength in comparison with en existing magnesium alloy so that the same can be used as a component for vehicles or electronic devices, requires heat insulation and durability.

Description

[0001] Magnesium alloy with excellent thermal diffusivity and strength [0002] Magnesium alloy with high thermal diffusivity and strength [

The present invention relates to a magnesium alloy, and more particularly, to a magnesium alloy which is lightweight and excellent in thermal diffusivity and strength and can be used as an automobile or an electronic device part.

Magnesium is a lightweight alloy with high specific strength and can be applied to various casting and machining processes, and can be applied to fields requiring weight reduction such as automobile and electronic device parts, and its application range is very wide. However, in order for magnesium to be used as an industrial material, other properties as well as lightweight properties are required.

For example, in the case of automobile parts, vibration must be absorbed in order to reduce vibrations generated during operation. In order to absorb vibrations, it is necessary to absorb vibration and radiate heat energy, and to be durable so as not to be damaged by vibration or external impact. In electronic parts such as smart phones and LED lights, it is required to be excellent in moldability such as a thin plate shape so as to be manufactured in a light and thin shape, and to be capable of effectively emitting heat generated during use.

In order to satisfy the characteristics of various required components, a magnesium alloy to which an alloy element is added is used. However, when the alloy element is added to pure magnesium, the thermal diffusivity generally decreases and the heat dissipation property is lowered. The decrease in the thermal diffusivity of magnesium alloys is proportional to the amount of alloying elements added, and it is known that alloying elements among aluminum alloying elements have the greatest reduction effect.

A magnesium alloy having improved the thermal conductivity by improving this point has been proposed in Korean Patent Registration No. 10-1594857. The proposed magnesium alloy improves heat dissipation properties by adding yttrium, which is a rare earth metal, to magnesium. However, yttrium, which is a rare earth element, has a problem of high production cost due to high price.

A proposed magnesium alloy was proposed in Korean Patent No. 10-1600590. The proposed alloy contains zinc (Zn), tin (Sn), calcium (Ca), silicon (Si) and manganese Thus, the thermal conductivity is improved without using a rare-earth metal. However, the magnesium alloy has a problem in that it is difficult to use the magnesium alloy as a component material which is required to have durability due to poor strength characteristics.

Korean Patent Registration No. 10-1594857 (Title of the Invention: Process for producing magnesium alloy for thermal processing and excellent flame retardancy for plastic working) Korean Patent Registration No. 10-1600590 entitled Magnesium Alloy for Heat Treatment and Excellent Flame Retardancy for Plastic Processing)

Accordingly, it is an object of the present invention to provide a method of manufacturing a semiconductor device in which magnesium (Mg) is added in an amount of 0.1 to 4.0 wt% aluminum (Al), 0.5 to 2.0 wt% copper, 1.0 to 6.0 wt% zinc (Ni), 0.1 wt% or less of manganese (Mn), 0.1 wt% or less of nickel (Ni) and 0.1 wt% or less of silicon (Si) to effectively dissipate heat energy and to provide a magnesium alloy excellent in strength .

In order to achieve the above object, the magnesium alloy according to the present invention comprises 0.1 to 4.0 wt% aluminum (Al), 0.5 to 2.0 wt% copper (Cu), 1.0 to 6.0 wt% zinc (Zn) Mn, 0.1 wt% or less of nickel, 0.1 wt% or less of silicon, and magnesium and other unavoidable impurities.

It is preferable that the content of copper (Cu) and zinc (Zn) satisfy 0.05? Copper / copper? Zinc + Zn? 0.6.

The magnesium alloy preferably has a tensile strength of 200 to 250 MPa, a yield strength of 150 to 180 MPa, and a thermal diffusivity of 40 mm 2 / s or more.

It should be understood, however, that the terminology or words of the present specification and claims should not be construed in an ordinary sense or in a dictionary, and that the inventors shall not be limited to the concept of a term It should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be properly defined. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention, and not all of the technical ideas of the present invention are described. Therefore, It is to be understood that equivalents and modifications are possible.

As described in the above construction and operation, the present invention is characterized in that aluminum (Al), copper (Cu), zinc (Zn), manganese (Mn), nickel (Ni), and silicon It is possible to improve the thermal diffusivity and strength as compared with the conventional magnesium alloy by improving the content ratio of the magnesium alloy, and thus it can be utilized as a material for parts of automobiles and electronic devices requiring heat dissipation characteristics and durability.

Hereinafter, preferred embodiments according to the present invention will be described in detail.

The present invention relates to a magnesium alloy, and more particularly, to a magnesium alloy which is excellent in thermal diffusivity and strength, and which is excellent in thermal diffusivity such as aluminum (Al), copper (Cu), zinc (Zn), manganese (Mn), nickel (Ni) Mg) and the remaining unavoidable impurities.

<Aluminum (Al)>

Aluminum (Al) plays a role in increasing the strength of the alloy and improving fluidity and castability. Such aluminum is preferably included in the range of 0.1 to 4.0% of the total weight of the alloy. That is, when the content of aluminum exceeds 4%, the thermal diffusivity and the tensile property deteriorate. When the content of aluminum is less than 0.1%, the flowability and casting are deteriorated.

<Copper (Cu)>

Copper (Cu) increases the thermal diffusivity through secondary phase formation (MgCu) and improves the alloy strength according to the hardening effect. It is preferable that such copper is contained in the range of 0.5 to 2.0% of the total weight of the alloy. That is, when the copper content is less than 0.5%, the effect of improving the strength is deteriorated. When the content exceeds 2.0%, the corrosion resistance is deteriorated.

&Lt; Zinc (Zn) >

Zinc (Zn) increases the thermal diffusivity through secondary phase formation (MgZn) and improves the castability and strength of the alloy. It is preferably contained in the range of 1.0 to 6.0% of the total weight of the alloy. When the content of zinc (Zn) exceeds 6%, the corrosion resistance and toughness are deteriorated. When the content is 1.0% or less, the original purpose can not be achieved.

<Copper (Cu) / {Copper (Cu) + Zinc (Zn)}>

In the present invention, it is preferable that the content ratio of copper / copper (Cu) + zinc (Zn) is 0.05 to 0.6. If the stomach content ratio is less than 0.05, There is a problem of poor composition.

&Lt; Mn (Mn) >

Manganese improves corrosion resistance by bonding with harmful harmful impurities in alloys, and improves strength at fast cooling rate. If the content of manganese is high, the mechanical properties are deteriorated, so it is recommended to add 0.1% or less of the total weight of the alloy.

&Lt; Nickel (Ni) >

Nickel is a hazardous element that is prohibited from being used, but it plays a role of improving the corrosion resistance of the alloy. When nickel is added, it is preferable to add 0.1% or less of nickel to the total weight of the alloy. The corrosion resistance is not remarkably improved.

&Lt; Silicon (Si) >

Silicon improves fluidity and strength. It is preferably contained in an amount of 0.1% or less of the total weight of the alloy. When the amount of silicon exceeds 0.1%, there is a problem in that the brittleness is increased.

A magnesium alloy casting having the above composition has excellent thermal diffusivity and strength. Hereinafter, a specific embodiment of the present invention will be described.

<< Examples >>

(1) Sample preparation

Magnesium alloys (Examples 1 to 4) and conventional magnesium alloys (Comparative Examples 1 to 4) formed according to the present invention were each made of the following ASTM Subsize standard test pieces.

Furtherance
(weight%) Al Cu Zn Mn Ni Si Mg
Example

One 3.5 One 0.5 0.1 0.1 0.1 Honey. 2 2 5 One 0.1 0.05 0.1 Honey. 3 1.5 6 One 0.1 0.1 0.05 Honey. 4 One 5 1.5 0.05 0.1 0.1 Honey.
Comparative Example

One 9 - 0.5 0.2 0.2 0.1 Honey. 2 6 0.5 0.5 0.1 0.2 0.2 Honey. 3 5 2 7 0.1 0.1 0.2 Honey. 4 4 8 6 0.2 0.1 0.1 Honey.

<Specimen>

division Center
Street
(G) width
(w) thickness
(T) Shoulder part
radius
(R) Specimen
Total length
(L) Parallel portion
Length
(A) Bottom
width
(C) Subsize
(Plate)
25
6.25
3.05
6 100
More than
32
10

Unit: mm

(2) Thermal diffusivity test

Thermal diffusivity.α is the thermal property that determines the rate at which heat propagates due to the conductivity of the material during the temperature change over time. The higher the thermal diffusivity, the faster the heat propagation. The thermal conductivity of each of the specimens of Examples 1 to 4 and Comparative Examples 1 to 4 was measured with a conductivity meter, and the thermal diffusivity was measured by the following formula.

α = λ / (C _P × ρ)

(Where α: thermal diffusivity, λ: thermal conductivity, C _P : specific heat, ρ: density)

The measured thermal diffusivity is as follows.

alloy Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Thermal diffusivity
(Mm 2 / s)
47
47
50
52
29
35
32
25

As a result of the thermal diffusivity test, the thermal diffusivity of the example was measured to be 47 to 52 mm 2 / s, which is higher than the thermal diffusivity of the comparative example (29 to 35 mm 2 / s).

(3) Strength test

Tensile strength and yield strength of each of the specimens of Examples 1 to 4 and Comparative Examples 1 to 4 were measured using an all-purpose material tester (Instron 5982). The measurement results are as follows.

alloy Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 The tensile strength
(MPa)
230
210
220
200
180
170
160
180 Yield strength
(MPa)
180
170
160
150
130
120
110
140

Experimental results The examples have tensile strengths of 200 to 230 MPa and yield strengths of 150 to 180 MPa, whereas the comparative examples have tensile strengths of 160 to 180 MPa and 110 to 140 MPa yield strengths.

As described above, the present invention can be utilized as a material for parts of automobiles and electronic devices requiring heat dissipation characteristics and durability by improving thermal diffusivity and strength as compared with conventional magnesium alloys.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. It is therefore intended that such variations and modifications fall within the scope of the appended claims.

Claims (3)

In the magnesium alloy,
0.1 to 4.0 wt% aluminum (Al), 0.5 to 2.0 wt% copper, 1.0 to 6.0 wt% zinc, 0.1 wt% or less manganese (Mn), 0.1 wt% or less nickel (Ni) % Or less of silicon (Si), magnesium (Mg) remaining, and other unavoidable impurities. The method according to claim 1,
Wherein the copper (Cu) and zinc (Zn) contents satisfy 0.05? Cu / Cu? Zn? 0.6. The method according to claim 1,
Wherein the magnesium alloy has a tensile strength of 200 to 250 MPa, a yield strength of 150 to 180 MPa and a thermal diffusivity of 40 mm 2 / s or more.