KR101394142B1 - Method for coating surface of magnesium alloy substrate - Google Patents

Abstract

The present invention relates to a method for processing the surface of a magnesium alloyed substrate comprising a step of forming a passive state solution film on a base layer by taking the base layer formed of a magnesium alloy out after precipitating the base layer in a passive state solution; and a step of forming a passive solution layer by processing one side or both sides of the base layer on which the passive state solution film is formed through atmospheric plasma treatment.

Description

[0001] METHOD FOR COATING SURFACE OF MAGNESIUM ALLOY SUBSTRATE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment method for a magnesium alloy substrate used for various products or devices, and more particularly, to a method for surface treatment of a magnesium alloy base material, And then forming the passivation layer through an atmospheric pressure plasma treatment or a heat treatment, thereby improving the corrosion resistance, corrosion resistance, paint adhesion, and metal quality of the magnesium alloy base material.

Recently, magnesium alloy has been widely used in various fields such as automobiles, cameras, mobile phones as well as automobiles, such as computers, because it is lightweight and excellent in electromagnetic shielding and heat radiation.

However, in order to put such a magnesium alloy material into practical use, a surface treatment must be separately performed to secure durability for various internal parts and external parts.

As a general surface treatment of such a magnesium alloy material, a chemical treatment method of immersing a magnesium alloy in a chromate-chloride-containing treatment liquid containing hexavalent chromium has been widely used, but hexavalent chromium, which is a heavy metal, is not only fatal to the human body, There is a problem that it causes pollution problem, and therefore, there is a strict regulation on working environment and wastewater treatment.

As a non-chromate conversion treatment method for replacing the conventional chromate-chloride conversion treatment, there has been proposed a phosphate treatment method in which a metal such as zirconium, titanium, or zinc is added to magnesium phosphate. However, , There is a limitation in that it is not possible to impart insufficient practicality, sufficient corrosion resistance, rust resistance and film adhesion.

On the other hand, the 'processing solution for magnesium alloy, the surface treatment method, and the magnesium alloy substrate' (referred to as Document 1) disclosed in Korean Patent Publication No. 2002-0077150 (October 11, 2002) It is known.

In reference to the above-mentioned document 1, it has been found that a magnesium alloy containing a phosphoric acid ion and a permanganate ion as a means for imparting paint adhesion, corrosion resistance and rust preventive property to a magnesium alloy and having a pH of 1.5 to 7 Liquid and surface treatment methods.

However, in such a conventional method, since the chemical liquor must be in a pH range of 2.0 to 4.0, which is a strong acidic treatment condition, if the pH of the chemical liquor exceeds 7, for example, And the reproducibility reliability of the coating is deteriorated, so that sufficient corrosion resistance and film adhesion can not be obtained.

According to an aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: depositing a base layer made of a magnesium alloy in a passive solution to form a passive solution film; and forming a passive layer through atmospheric pressure plasma treatment or heat treatment, And it is an object of the present invention to provide a magnesium alloy base material that can improve corrosion resistance, corrosion resistance, paint adhesion, and metallic quality.

In addition, since the base layer formed of a magnesium alloy is immersed in a passive solution to form a passive solution film, the present invention can further shorten the processing time of the passive layer formed through atmospheric plasma treatment or heat treatment There is another purpose.

In addition, the present invention does not use hexavalent chromium and heavy metals for surface treatment of a substrate layer made of a magnesium alloy, thereby reducing facility investment such as work environment for treatment of environmental pollution and wastewater treatment There is another purpose.

The above and other objects and features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.

Then, with respect to either one side or both sides of the substrate layer on which the passive liquid film is formed And forming a passive layer by atmospheric pressure plasma treatment.

According to another aspect of the present invention, there is provided a method for forming a passive solution film, comprising: immersing a substrate layer made of a magnesium alloy in a passive solution;

And forming a passivation layer on the one or both surfaces of the substrate layer 100 having the passive liquid film formed thereon by heat treatment at 50 to 150 DEG C for 1 to 30 minutes.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As described above, according to the present invention, a base material layer made of a magnesium alloy is immersed in a passive solution to form a passive solution film, and then the passive layer is formed by atmospheric pressure plasma treatment or heat treatment. Therefore, the magnesium alloy base material is required to have anti- , Paint adhesion, and metal quality sensitivity.

In addition, the present invention immerses a substrate layer made of a magnesium alloy in a passive solution to form a passive solution film, thereby further reducing the processing time of the passive layer formed through atmospheric plasma treatment or heat treatment to provide.

In addition, since the present invention does not use a heavy metal for surface treatment of a substrate layer made of a magnesium alloy, it provides another effect of further reducing facility investment such as work environment and wastewater treatment for preventing environmental pollution .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a first embodiment of the present invention in which the surface treatment of the magnesium alloy base according to the present invention is performed.
Fig. 2 is a second embodiment showing a schematic state in which the surface treatment of the magnesium alloy base material according to the present invention is performed.
3 is a flow chart of a first embodiment showing a process for performing a surface treatment of a magnesium alloy substrate according to the present invention.
4 is a flow chart of a second embodiment showing a process for performing surface treatment of the magnesium alloy base material according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of the preferred embodiments of the present invention, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of example at least one embodiment, And should not be construed as limiting the scope of the present invention.

It should be noted that the same reference numerals are used for the same components in different drawings in the present invention, and the same reference numerals are given to the same components whenever possible, The present invention will be described in detail with reference to the drawings shown in FIG.

Generally used magnesium alloy has excellent non-toughness (specific gravity strength), high heat conductivity and thermal diffusibility, lightweight, vibration absorbing property, electromagnetic wave shielding, film substitution due to thinning of materials such as various products and devices, Casting, processability, and recyclability. On the other hand, there is a disadvantage that surface treatment must be performed essentially as in the present invention due to high oxidation resistance and low corrosion resistance.

The present invention relates to a magnesium alloy material having the above-mentioned characteristics and a base material layer 100 (which is called a "base material layer" or a base material (base material layer)) provided with die casting, Base layer ") is immersed in a passive state solution to form a passive solution film, which is then subjected to atmospheric pressure plasma treatment or heat treatment to form a passive layer on either one side or both sides, The magnesium alloy base material is improved in corrosion resistance, heat resistance, corrosion resistance, paint adhesion, and metal feelability, thereby ensuring durability for various interior parts and exterior parts.

The reliability test conditions of the substrate made of the magnesium alloy material according to the present invention include a constant temperature and humidity test conducted at a temperature of 60 DEG C and a humidity of 90% for 240 hours, a temperature of -40 DEG C for 30 minutes to 80 DEG C for 30 minutes The surface treatment technique for magnesium alloy materials is important because it is required to be free from deformation or deterioration in a cold temperature thermal shock test carried out over 100 cycles to a long period of time and a salt water test conducted for 5 hours to 120 hours of salt water It is true.

First, the construction means and the first embodiment process for solving the problems according to the present invention will be described with reference to the accompanying drawings.

As shown in FIGS. 1, 2 and 3, a substrate layer 100 made of a magnesium alloy is immersed in a passivation solution filled in a solution tank (not shown) at room temperature, (Step S201).

The passivation layer 120 is formed on at least one surface or both surfaces of the substrate layer 100 on which the passivation solution film 110 is formed by an atmospheric pressure plasma treatment (also referred to as "atmospheric pressure plasma"). (Step S202).

Here, the atmospheric pressure plasma treatment brings the plasma generated under atmospheric pressure into contact with the passive solution formed on the surface of the magnesium alloy substrate, that is, the substrate layer 100, to deposit the passive layer 120.

As one example of the surface treatment using plasma, there is a method using a plasma at a low temperature and a low pressure. In such a surface treatment method using a low temperature and low pressure plasma, a plasma is generated in a low temperature and low pressure vacuum chamber, Wherein the generated plasma is brought into contact with the surface of the substrate to treat the surface of the substrate.

However, such a surface treatment method using a plasma at a low temperature and a low pressure has an excellent surface treatment effect, but a vacuum apparatus is required to maintain a low pressure, and it is difficult to apply to a continuous process. Therefore, Atmospheric pressure plasma treatment is widely used.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe constituent means and a second embodiment of the present invention in reference to the accompanying drawings.

As shown in FIGS. 1, 2 and 4, a substrate layer 100 made of a magnesium alloy is immersed in a passivation solution filled in a solution tank (not shown) at room temperature and then taken out to form a passivation solution film 110 (Step S301).

Next, a passivation layer 120 is formed on one or both surfaces of the base layer 100 on which the passivation solution layer 110 is formed by heat treatment at a temperature ranging from 50 to 150 ° C. for 1 to 30 minutes And the step S302 includes the step S302.

At this time, if the heat treatment temperature is less than 50 ° C, vaporization of the passivation solution is not easily performed, and the deposition rate of the passivation layer 120 may be lowered. On the other hand, when the heat treatment temperature exceeds 150 ° C, It is preferable to adjust the temperature appropriately in the above-mentioned range of 50 to 150 ° C.

In addition, the heat treatment time for performing the surface treatment on the heat treatment substrate layer 100 may vary depending on the passivation solution, but if the heat treatment time is less than 1 minute, the passivation layer 120 may be incompletely deposited, On the other hand, if the heat treatment time exceeds 30 minutes, the process time for forming the passivation layer 120 becomes unnecessarily long and can act as a waste factor. Therefore, it is also possible to appropriately control the temperature within the range of 1 to 30 minutes Lt; / RTI >

Meanwhile, in the present invention, the base material layer 100 made of magnesium alloy material, such as die casting, injection molding, plate material, etc., may be made of a metal such as Al, Cu, Ti, Ni, Si, , And Zr, Fe, Ca, Li, and Be.

The thickness (t1) of the base material made of the base material layer 100, that is, the magnesium alloy is preferably 0.06 to 0.1 mm. However, it is preferable to use the base material 100 in terms of chemical and physical properties required for polishing and machining The thickness t1 may be 0.04 to 4 mm, depending on the purpose or the purpose of use.

In addition, it is preferable that the surface of the base layer 100 is removed by a sufficient degreasing and cleaning process before the base layer 100 mentioned above is immersed in the solution tank.

In other words, when foreign substances are present on the surface of the base layer 100, the passivation solution is not uniformly formed due to the surface tension, which may adversely affect formation of the passivation layer 120.

In addition, the passivation solution may be prepared by dissolving the passivation layer 120, that is, ethanol, methanol, isopropyl alcohol, butyl alcohol, or the like, having good affinity with the magnesium alloy during the formation of the magnesium oxide (MgO) Alcohol, and Octyl alcohol. The present invention is characterized in that it is an alcohol-based material formed by mixing one or two or more selected from the group consisting of alcohol and octyl alcohol.

On the other hand, by using distilled water which is a non-alcoholic substance or a non-volatile substance having a pH of 6.0 or more as the passive solution, it is more environmentally friendly than the case of using the above-mentioned alcoholic substance or nonvolatile substance, Is not volatilized, it is advantageous that the preparation time for post-process atmospheric plasma treatment or heat treatment can be set more margin.

In addition, the present invention can be applied to the passive layer 120 by using a synthetic resin coating or a powder coating, an electro deposition coating, an electrostatic coating, or the like to improve the corrosion resistance of the magnesium alloy substrate, (For example, a urethane paint excellent in adhesion, chemical resistance, weatherability and impact absorbability) or a color paint having various colors by electrostatic painting and the like, (S303, S303) of forming a protective layer (130) on the substrate.

At this time, the thickness of the coating layer on the protective layer 130 is preferably 5 to 10 占 퐉, but may be 2 to 20 占 퐉, depending on the chemical and physical properties of the base material, At this time, the outer surface of the base layer 100, that is, the surface of the base layer 100 is uniformly coated even to the inside of the base layer 100, thereby improving the weather resistance and preventing corrosion of the surface.

The passivation layer 120 further enhances the attraction force of the coating material when the protective layer 130 is formed. Further, the passivation layer 120 has a more uniform and stable protective layer 130 ) Of the thickness of the protective layer 130, and at the same time, it improves the sensitivity of the metal. Therefore, the thickness of the protective layer 130 is 0.05 to 0.1 times the thickness of the protective layer 130 considering the chemical and physical characteristics of the base material, It is preferable that the thickness is 0.1 to 2.0 탆.

Meanwhile, the synthetic resin coating included in the above-mentioned formation of the protective layer 130 can be achieved by dispersing a coloring agent such as a pigment in a medium containing synthetic resin as a main component, Acrylic resin, an amino resin, a thermosetting acrylic resin, an unsaturated polyester resin, an epoxy resin, a urethane resin, a urethane resin, or a urethane resin. , Phenol type, vinyl type, silicone type and the like.

Powder coating included in the formation of the protective layer 130 may be performed by coating the passivation layer 120 formed on the surface of the base layer 100 formed of the magnesium alloy with the synthetic resin in powder form As a powder coating method, the powder coating to be used at this time is one of a solventless type coating material and a coating film is formed by solid state powder.

The powder coating included in the formation of the protective layer 130 includes a flow dipping method, an electrostatic flow dipping method, and an electrostatic spraying method. Among these electrostatic spraying methods, a typical electrostatic spraying method is an electrostatic spray gun Spray gun is applied to the tip of the spray gun and the powder drawn through it is negatively charged so that the coated object of the magnesium alloy substrate having the opposite electric charge is treated and then heated and melted in the drying furnace, Layer (this will be referred to as "protective layer").

In addition, the electrodeposition coating included in the formation of the protective layer 130 is completely immersed in a tank filled with the electrodeposition paint to uniformly coat not only the surface of the magnesium alloy substrate but also the inside thereof, which further enhances the rustproofing property .

In addition, the electrostatic coating included in the formation of the protective layer 130 is complicated in shape using static electricity. However, because the paint can be painted evenly over a wide area, the arrival efficiency is higher than the spraying method, Metal, and the like.

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 or scope of the invention.

Accordingly, the technical scope of the present invention should be defined by the claims of the present invention, rather than being limited to those described in various embodiments as mentioned above.

100: substrate layer
110: Passivation solution film
120: passive layer
130: Protective layer

Claims (6)

A step (S201) of immersing the substrate layer 100 made of a magnesium alloy in the passive solution and then removing the passive solution film 110;
And forming a passivation layer 120 on at least one side or both sides of the base layer 100 on which the passivation solution film 110 is formed by atmospheric pressure plasma treatment S202. / RTI > A step (S301) of immersing the substrate layer (100) made of a magnesium alloy in a passive solution and then removing the passivation solution film (110);
A step S302 of forming a passivation layer 120 by heat treatment on either or both surfaces of the substrate layer 100 on which the passivation solution film 110 is formed at a temperature ranging from 50 to 150 DEG C for 1 to 30 minutes Including,
The base layer 100 is a magnesium alloy selected from at least one of Al, Cu, Ti, Ni, Si, Cr, Mn, Zn, Zr, Fe, Ca, (100) has a thickness (t1) of 0.04 to 4 mm. The method according to claim 1 or 2, wherein a protective layer (130) having a thickness of 2 to 20 탆 is formed on the passivation layer (120) by any one of synthetic resin coating, powder coating, electrodeposition coating and electrostatic coating (S203, S303). ≪ / RTI > The surface treatment method of claim 3, wherein the thickness of the passivation layer (120) is 0.05 to 0.1 times the thickness of the passivation layer (130). The method according to claim 1, wherein the base layer (100) is made of at least one selected from the group consisting of Al, Cu, Ti, Ni, Si, Cr, Mn, Zn, Zr, Fe, Ca, Wherein the base layer (100) has a thickness (t1) of 0.04 to 4 mm. The magnesium alloy substrate according to claim 1 or 2, wherein the passive solution is an alcohol-based material formed by mixing one or two or more selected from ethanol, methanol, isopropyl alcohol, butyl alcohol and octyl alcohol / RTI >

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