KR101378531B1 - Thermal spray coating method of aluminum panel for electromagnetic pulse protection and the aluminum panel - Google Patents

Abstract

The present invention relates to a thermal spray coating method for an aluminum panel for electromagnetic pulse protection and the aluminum panel, and more specifically, to an aluminum panel having a roughness layer on a surface thereof and a metal coating layer formed on the roughness layer through wire arc spraying, wherein a thickness of the aluminum panel is 0.5 to 1 mm and a thickness of the metal coating layer is 100 to 300μm. According to the present invention, a high protection performance against low-frequency electromagnetic fields as well as electric fields, excellent adhesion between the base aluminum panel and the metal coating layer, and excellent electromagnetic coupling at connection portion between aluminum panels for electromagnetic pulse protection can be achieved. Additionally, it is possible to provide an aluminum panel with excellent electromagnetic pulse protection performance and a light weight, thereby enabling effective production of a composite panel for electromagnetic pulse protection, which is applied to a military mobile communication shelter.

Description

Thermal spray coating method of aluminum panel for electromagnetic pulse protection and its aluminum panel {THERMAL SPRAY COATING METHOD OF ALUMINUM PANEL FOR ELECTROMAGNETIC PULSE PROTECTION AND THE ALUMINUM PANEL}

The present invention relates to a spray coating method of an aluminum panel for electromagnetic pulse protection, and more particularly, by forming a coating layer by spraying a wire on the aluminum panel, thereby satisfying the protective performance against electromagnetic pulse attack. The invention relates to a thermal spray coating method of an aluminum panel for electromagnetic pulse protection with excellent adhesion and electromagnetic coupling properties with a metal coating layer and an aluminum panel thereof.

In general, electromagnetic waves refer to wavelengths generated by the interaction between electricity and magnetism, and occur naturally in all electromagnetic products such as information and communication devices ranging from electrical household appliances around us to civilization.

These electromagnetic waves are constantly being debated and harmful to the human body according to their strength, and technologies for blocking them and absorbing technologies have been continuously researched and developed, and detected and analyzed, and then used and utilized for various information. .

Electromagnetic Pulse (EMP) refers to the large energy that occurs naturally or artificially. Natural EMP refers to lightning. Artificial EMP refers to the pulse of powerful energy generated by the explosion of nuclear bombs or electron bombs. Can be.

As such, the electronic devices exposed to the EMP may be severely damaged due to the impact of a large energy pulse, leading to malfunction or breakdown. Measures should be taken for this purpose.

This protection technology for EMP is to surround any part of the space with electromagnetic conductor, to prevent the influence of the electromagnetic field from the outside, such as the human body or electronic equipment inside, or to prevent the influence of the electromagnetic field generated from the inside from reaching the outside. Say.

Recently, North Korea's nuclear tests and threats of military provocations continue, and in major military facilities built to prepare for the attacks of nuclear weapons, electromagnetic pulse bombs and electronic warfare terrorism in case of emergency, electromagnetic pulses of up to 50,000 V / m intensity are effectively protected. The electromagnetic pulse protection measures that can be done are very important. In addition to the EMP protection measures of these military facilities, the EMP protection performance of the mobile communication shelter (Shelter) for the operation of the military command communication network is also very important.

In order to protect major military installations from EMP, which occurs along with explosion pressure, heat and radiation during nuclear explosions, and EMP bombs known to be developing by North Korea and terrorism by certain means, generally electrically conductive metals (mainly copper, iron , Aluminum, etc.) to protect the EMP by completely sealing the six sides of the office and electromagnetically interconnecting them according to the protection level. In addition, by connecting and assembling the iron plate of the six-sided made of a conductive material, such as "EMP protective cabinet" of Patent No. 10-0990828 to protect the important electronic devices. However, the EMP protection is excellent in the protection effect of the electric field but has a disadvantage of insufficient protection effect of the low frequency magnetic field.

On the other hand, since mobile communication shelter is mounted and operated in a vehicle, it is subject to load limitation, so instead of the thick and heavy steel plate used for fixing facilities as a main barrier, sandwich panels made of thin and light aluminum and polyurethane-based insulation are electromagnetic pulse rooms. We use as good news.

The sandwich panel, which is composed of thin and light aluminum and polyurethane-based insulation constituting the mobile communication shelter, can satisfy the protection requirements of the shelter against electric fields with conductive aluminum, but for low frequency magnetic fields, especially 100 KHz to 10 MHz band There is a disadvantage that it is difficult to satisfy the protection performance of the shelter.

Therefore, there is an urgent need for the development of a protective material for high strength electromagnetic pulses, particularly a low frequency magnetic field, having excellent protection performance while maintaining the mechanical properties basically required by the shelter.

In addition, the electromagnetic pulse protection structure is designed to design the type and thickness of the protection material in order to meet the protection class standards required by the target to be protected, and to produce a structure that completely connects the six sides of the outside of the protection target electromagnetically . However, in general, the protective material is produced in a constant size, and in order to construct a hexahedral shelter having a size of about 2 to 3.5m in width and length, it is necessary to connect the protective material to expand the width and length. Therefore, the joint part between the joint and the corner between the protective materials is a very important factor in determining the protective performance.

In particular, the thin protective material is the most important is to solve the problem, although the top and bottom bond with the dissimilar material for durability, the connection of the joint parts between the same material to extend laterally, the electromagnetically perfect coupling to the corner connection, There is a problem in that the welding method is limited and practically difficult.

Therefore, while maintaining the mechanical properties basically required by the shelter, the electromagnetic coupling of the connection portion between the same material for the upper, lower adhesion, and laterally expanding with the heterogeneous material is very excellent, and the lightweight structure is good durability Protection against high-intensity electromagnetic pulses, in particular, the development of products with excellent protection against low frequency magnetic fields is urgently needed.

KR 10-0990828 B1

SUMMARY OF THE INVENTION An object of the present invention is to provide an aluminum panel for electromagnetic pulse protection, and by spraying wires on the aluminum panel to form a metal coating layer, it has a high protection performance against electric fields as well as a low frequency magnetic field, In addition to excellent adhesion between the metal coating layer, to provide a lightweight panel excellent in the electromagnetic coupling of the connection between the aluminum panel formed metal coating layer.

In addition, by forming a metal coating layer on the thin aluminum panel using the electric arc spraying method, it is possible to minimize the impact of the aluminum panel due to heat deformation and high-speed injection of the thermal spray material, thereby increasing the stability of the protective panel.

In addition, by optimizing the diameter of the wire and the thickness of the metal coating layer, when the composite panel for electromagnetic pulse protection using the aluminum panel having the metal coating layer of the present invention is configured, the electromagnetic pulse protection required performance up to 50,000 V / m strength To meet.

The spray coating method of the aluminum panel for electromagnetic pulse protection of the present invention for achieving the above object, (a) removing the oil and foreign matter of the aluminum panel, (b) blasting the aluminum panel surface (oxide) oxide Removing and forming a roughness layer; and (c) arc spraying a wire on the roughness layer of the aluminum panel to form a metal coating layer, wherein the aluminum panel has a thickness of 0.5 to 1 mm. The metal coating layer is characterized in that it is formed to a thickness of 100 ~ 300㎛.

 In the step (c), the wire has a diameter of 1.0 to 3.2 mm, and the wire is sprayed at an arc heat of 3,000 to 5,000 ° C. and a compressed air injection rate of 100 to 200 m / sec.

The adhesive strength of the aluminum panel and the metal coating layer is characterized in that 4,500 ~ 8,000 psi.

The wire is cobalt (Co), nickel (Ni), iron (Fe), nickel-cobalt alloy, nickel-iron alloy (Permalloy), nickel-iron-molybdenum alloy (Supermalloy) and nickel-iron-copper alloy (Mu- metal), and the wire is heated in a hydrogen atmosphere at a temperature of 900 ~ 1,100 ℃ for 2 to 4 hours, it is characterized in that by air cooling for 4 to 5 hours.

In the aluminum panel for electromagnetic pulse protection according to the present invention, an illuminance layer is formed on the surface of the aluminum panel, a metal coating layer formed by arc spraying of the wire is formed on the illuminance layer, and the thickness of the aluminum panel 1 is 0.5. It is ˜1 mm, the thickness of the metal coating layer 3 is characterized in that 100 ~ 300㎛.

The adhesive strength of the aluminum panel and the metal coating layer is characterized in that 4,500 ~ 8,000 psi.

The thermal spray coating method of the aluminum panel for electromagnetic pulse protection by this invention, and its aluminum panel have not only an electric field but also high protection against a low frequency magnetic field, and are excellent in the adhesive force of the base material aluminum panel and a metal coating layer, Electromagnetic coupling of the connection between aluminum panels for electromagnetic pulse protection is also very good.

In addition, by providing an aluminum panel having excellent electromagnetic pulse protection performance and lightweight structure, it is possible to effectively produce a composite panel for electromagnetic pulse protection, there is an advantage that can be applied to mobile communication shelter used in military units.

1 is a cross-sectional view of an aluminum panel for electromagnetic pulse protection according to the present invention.
Figure 2 is a perspective view of the electromagnetic panel protection aluminum panel according to the invention applied to the composite panel.
Figure 3 is a flow chart of the spray coating method of the aluminum panel for electromagnetic pulse protection according to the present invention.
4 is a view showing a method of forming a roughness layer on the aluminum panel for electromagnetic pulse protection according to the present invention.
5 is a view showing a method for forming a metal coating layer on the aluminum panel for electromagnetic pulse protection according to the present invention.

Hereinafter, a spray coating method of an aluminum panel for electromagnetic pulse protection and an embodiment of the aluminum panel will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of an electromagnetic pulse protection aluminum panel according to the present invention, Figure 2 is a perspective view of applying an electromagnetic pulse protection aluminum panel according to the present invention to a composite panel, Figure 3 is an electromagnetic pulse protection aluminum according to the present invention. 4 is a flowchart illustrating a spray coating method of a panel, and FIG. 4 is a view illustrating a method of forming an illuminance layer on an aluminum panel for electromagnetic pulse protection according to the present invention, and FIG. Is a diagram illustrating a method for forming a film.

First, the present invention is to provide an electromagnetic pulse protection aluminum panel (A) used when manufacturing the composite panel (B) for the purpose of protecting the electromagnetic pulse. As shown in FIG. 2, the composite panel B is formed by filling a polyurethane insulation 20 between the aluminum panel A for protecting electromagnetic waves and the general aluminum panel 10 according to the present invention.

That is, the aluminum panel A for electromagnetic pulse protection which concerns on this invention aims at the electromagnetic pulse protection of the mobile communication shelter equipment mounted and operated in a vehicle.

Since the electromagnetic pulse protective material of such mobile equipment is limited to the load, it is essential to use a lightweight protective material, and there should be no problems such as electromagnetic coupling between materials, mechanical impact strength, durability, and the like.

In addition, the low frequency band (100KHz ~ 20MHz) of the EMP is the magnetic field region, so that the magnetic wave ignores the electric wave, and in the high frequency band (20MHz ~ 1GHz), the electric wave is in phase with the magnetic wave and the plane wave perpendicular to the plane. Due to their dominance in form, the protection methods in each area should be applied differently.

Therefore, the aluminum panel A for electromagnetic pulse protection of the present invention maximizes the effect by protecting the magnetic wave and the electric wave using different materials, unlike the conventional electromagnetic shielding of the electromagnetic pulse with one material. As shown in FIG. 1, the roughness layer 2 is formed on the surface of the aluminum panel 1, and the metal coating layer 3 is formed on the roughness layer 2 by the spraying of the wire W. Therefore, the electric field in the form of a plane wave is protected by the aluminum panel 1, and the magnetic waves of the magnetic field are protected by the metal coating layer 3 formed in the roughness layer 2 of the aluminum panel 1.

Conventionally, the electric field is easily protected by a conductive metal, but a low frequency magnetic field in the 100 KHz to 10 MHz band is not easily protected, and in the present invention, a metal coating layer 3 having a high permeability magnetic is applied. By forming a strong magnetic field in the direction of the magnetic field to change the flow direction of the magnetic wave to the outside, the hysteresis effect is reduced to increase the absorption loss due to the resistance.

Wherein the aluminum panel (1) is a conductive material, to impart the electrical conductivity to the aluminum panel (A) for EMP protection to meet the protection performance of the high frequency electric field, while showing a basic protective effect on the low-frequency magnetic field, EMP protection Mechanical strength and durability are imparted to the aluminum panel (A). In addition, by spraying the ferromagnetic wire (W) on one surface of the aluminum panel (1) to form a metal coating layer (3), it gives a magnetic property to the aluminum panel (A) for EMP protection to protect the low-frequency magnetic field To improve.

At this time, the thickness of the metal coating layer 3 is preferably 100 ~ 300㎛, which meets the electromagnetic pulse protection performance required according to the application of the EMP protection aluminum panel (A), excessive weight increase or the base material aluminum It is thickness for preventing the deformation of the panel 1. That is, if the thickness of the metal coating layer 3 is less than 100㎛ hard to show the required protection performance, if it is larger than 300㎛ the weight increases, the manufacturing cost increases, the aluminum panel 1 can be deformed Because there is. And when the EMP protection aluminum panel (A) of the present invention is to be applied to mobile communication shelter equipment mounted and operated in a vehicle, the thickness of the preferred metal coating layer (3) is 150 ~ 200㎛.

When the metal coating layer 3 has a poor bonding strength with the base aluminum panel 1, the bonding strength of the composite panel B to which the EMP protection aluminum panel A of the present invention is applied is also poor. Bond strength is important, but in the present invention, the roughness layer 2 is formed on the surface of the aluminum panel 1, and the metal W is formed by arc-spraying the wire W at high temperature and high speed to form the metal coating layer 3, 4,500 to 8,000. has very good adhesion properties of psi. The method of spraying the said wire W is demonstrated in detail in the manufacturing method of the aluminum panel A for EMP protection of this invention below.

Moreover, it is preferable to make thickness of the aluminum panel 1 which is the said base material into 0.5-1.0 mm, More preferably, use 0.7 mm. In order to apply the EMP protective aluminum panel A of the present invention to a mobile communication shelter device mounted and operated in a vehicle, the effects of mechanical strength, durability, and load for serving as a box-shaped structure of the device are examined. It is decided. The aluminum panel 1 may be formed of aluminum 50 series.

EMP protective aluminum panel (A) of the present invention as described above is excellent in the protection performance of the electric and magnetic fields, as well as light weight structure suitable for application to mobile communication shelter equipment mounted and operated in the vehicle, excellent adhesion performance Since the durability of the shelter is also excellent. In addition, since both the electric field and the magnetic field are protected by the EMP protective aluminum panel A of the present invention, there is no need to use a separate magnetic field protective member, so that the connection between the EMP protective aluminum panel A is welded or riveted. The connection part may also be formed of a metal coating layer 3, and thus, the electromagnetic coupling property of the connection part may also be very excellent.

Hereinafter, a method of forming the metal coating layer 3 on the aluminum panel 1 according to the present invention, that is, a method of spray coating of the aluminum panel A for electromagnetic pulse protection will be described in detail.

The spray coating method according to the present invention, as shown in Figure 3, (a) removing the oil and foreign matter of the aluminum panel (1), (b) blasting the surface of the aluminum panel (1) to oxides (oxide) Removing and forming the roughness layer (2), and (c) arc spraying the wire (W) on the roughness layer (2) of the aluminum panel (1) to form the metal coating layer (3). It is characterized by. This will be described below in detail step by step.

(a) removing oil and foreign matter from the aluminum panel 20.

First, oil and foreign substances of the aluminum panel 1 are removed. This is because the surface of the aluminum panel 1, which has been processed for the first time, is contaminated with oil or the like, because the contaminants such as oil affect the metal coating layer 3 formed through the thermal spraying. That is, the interface may be generated due to the contaminants such as oil, because the adhesion between the aluminum panel 1 and the metal coating layer 3 is degraded, so that the peeling phenomenon of the metal coating layer 3 occurs.

In order to prevent this phenomenon, the aluminum panel 1 is washed before processing to prevent the metal coating layer 3 from peeling off.

Here, the method of washing the aluminum panel 1 may be a method of using alcohol, acetone, thinner solvent and isopropyl alcohol (IPA) or a method of using ultrasonic cleaning, and the aluminum panel (1) If oil and foreign substances can be removed, the method is not limited.

(b) blasting the surface of the aluminum panel 1 to remove oxides and to form a roughness layer 2.

As described above, when the cleaning is completed, the surface of the cleaned aluminum panel 1 is blasted to remove oxides, thereby forming the roughness layer 2.

The oxide is removed and the roughness layer 2 is formed by spraying the particles 31 having a large size onto the surface of the aluminum panel 1 using the blasting machine 30 as shown in FIG. 4. At this time, the removal of the oxide and the formation of the roughness layer 2 is to improve the adhesion and bonding strength between the aluminum panel 1 and the metal coating layer (3).

Here, as the fine particles 31 used in the blasting machine 30, glass beads, sand, iron beads, alumina, etc. may be used, and the size of the particles is not limited, but may be generally used in the range of about 0.1 ~ 0.5mm. The injection speed and pressure are also not limited.

If the roughness layer 2 is not formed in the present invention, the required adhesion strength between the metal coating layer 3 and the aluminum panel 1 cannot be secured, so that the blasting process is preceded before the formation of the metal coating layer 3. It should be.

(c) arc-spraying a wire (W) on the roughness layer (2) of the aluminum panel (1) to form a metal coating layer (3).

Next, the metal coating layer 3 is formed by spraying a wire W on the roughness layer 2 of the aluminum panel 1. Here, the method of thermal spraying the wire (W) uses an electric arc sprayer 40, as shown in FIG.

The electric arc sprayer 40 uses two wires as electrodes, and generates an arc at the torch tip 42 at the end of the electrode to melt the wire W supplied through the wire guide 41 by a roller. At the same time, a method of forming a metal coating layer 3 on the aluminum panel 1 by spraying and flying compressed air.

Since the electric arc sprayer 40 melts the wire W at a temperature of up to several thousand degrees in the torch tip 42, the characteristics and components of the wire W may be deformed by arc heat, and the compressed air By flying the molten wire (W) at a speed of several hundred m / sec. To impinge on the aluminum panel (1) as a base material, the metal coating layer (3) is to be formed. Therefore, the thin aluminum panel 1 used as the base material may exhibit deformation or bending deformation of the surface of the aluminum panel 1 due to heat and collision energy, and may be formed between the surface of the aluminum panel 1 and the metal coating layer 3. It affects the adhesion and the bond and the difference in the bond strength appears.

Therefore, in the present invention, in order to make the adhesive strength between the aluminum panel 1 and the metal coating layer 3 to 4,500 ~ 8,000 psi, the arc heat of the arc sprayer 40 is preferably set to 3,000 ~ 5,000 ℃, The jet blowing speed of the compressed air is preferably 100 to 200 m / sec, most preferably the arc heat is 4,100 ° C., and the jet blowing speed is 150 m / sec. To be.

This is because when the arc heat of the arc sprayer 40 is less than 3,000 ° C., the melting of the wire W is not smooth, and thus the bonding strength is reduced. When the temperature of the arc sprayer 40 is more than 5,000 ° C., the oxide is increased on the surface of the thermal spraying material by excessive melting. This is because the electromagnetic properties of the material is lowered, and the jet blowing speed of the compressed air is 100 m / sec. When less than or equal to the surface oxidation in the air of the molten wire (W) increases the protection performance is lowered, the impact energy to the aluminum panel (1) is less, the adhesion and bonding strength is lowered, 200m / sec. This is because when the abnormality is delivered to the aluminum panel 1 due to the excessive injection speed, the characteristics of the aluminum panel 1 and the molten wire W can be modified.

The reason why the adhesive strength is 4,500 to 8,000 psi is because when the adhesive strength is less than 4,500 psi, the bonding strength is poor and durability is lowered, and when it is larger than 8,000 psi, the manufacturing cost increases more than necessary.

And since the wire (W) used in the arc sprayer 40 is melted at a temperature of several thousand degrees generated instantaneously in the torch tip 42, there is a difference in the degree of melting depending on the diameter of the wire (W) It affects the adhesive force with the phosphorus aluminum panel 1 and the roughness of the surface of the metal coating layer 3. Therefore, the diameter of the wire (W) used in the arc sprayer (40) is limited so as not to cause the above problems, the diameter of the wire (W) is preferably 1.0 to 3.2mm, most preferably It is 1.6mm. This is because when the diameter of the wire W is smaller than 1.0 mm, the surface of the metal coating layer 3 is formed to be rough, and when the diameter of the wire W is larger than 3.2 mm, the adhesive force with the aluminum panel 1 may be poor.

In addition, the metal coating layer (3) has an important characteristic of improving the electromagnetic pulse protection performance by imparting magnetic properties, but when the thickness is thicker than the appropriate thickness increases the weight is limited to the application to mobile communication shelter equipment, manufacturing cost is increased In addition to the disadvantages, the condensation force due to the quench solidification on the surface of the aluminum panel 1 is strongly generated, the deformation of the aluminum panel 1 is bent. Therefore, the thickness of the metal coating layer 3 is 100 ~ 300㎛. And, in the case of mobile communication shelter equipment mounted on the vehicle, the thickness of the more preferable coating layer (3) is 150 ~ 200㎛.

On the other hand, the wire (W) is cobalt (Co), nickel (Ni), iron (Fe), nickel-cobalt alloy, nickel-iron alloy (Permalloy), nickel-iron-molybdenum alloy in order to improve the electromagnetic pulse protection performance (Supermalloy) and nickel-iron-copper alloy (Mu-metal), preferably one of the most preferably nickel-iron-molybdenum alloy. This is because the magnetism of the nickel-iron-molybdenum alloy is the strongest, and the adhesion performance with the aluminum panel 1 is also excellent.

In addition, the wire W may be heat treated to further improve the protection performance of the magnetic field. Here, the heat treatment is a ferromagnetic wire (W) is heated for 2 to 4 hours at a temperature of 900 ~ 1,100 ℃ in a hydrogen atmosphere of a general heat treatment furnace, and air cooled in the furnace for 4 to 5 hours.

At this time, when the temperature of the heat treatment is 400 ℃ starts to show a rapid increase in permeability, when the temperature is 1,100 ℃ or more, a part of the metal components begin to dissolve and agglomeration occurs with each other, the magnetic properties of the wire (W) Since it starts to fall, it heat-processes at the temperature of 900-1,100 degreeC by all means. When the heat treatment time is less than 2 hours, due to the rapid temperature rise of the heat treatment apparatus, a time delay occurs with the wires W inside the heat treatment furnace, so that sufficient time for the reaction cannot be obtained. Since it falls, it heats for 2 to 4 hours. The heat treatment is preferably performed in a general heat treatment furnace, which is intended to reduce the internal stress of the wire (W) to improve the initial permeability of isotropy. When the heat treatment is performed in a magnetic field, the effect of improving permeability can be increased, but there is a disadvantage of having a unidirectional characteristic in the direction of the magnetic field. In addition, the air cooling uses a forced cooling method, a detailed description thereof will be omitted since the forced cooling method in the furnace is already generalized in the art. And the said air-cooling time is made into 4 to 5 hours because sufficient cooling is not performed when air cooling time is less than 4 hours, and when it exceeds 5 hours, economy is inferior.

The wire W heat-treated as described above is greatly improved in magnetic properties, and the protection performance of the metal coating layer 3 formed on the aluminum panel 1 is significantly increased.

EMP protective aluminum panel (A) of the present invention manufactured as described above may be laminated together with the general aluminum panel 10 and the polyurethane insulation 20 as shown in FIG. 2 to form a composite panel (B), The composite panel B thus constructed can be applied not only to mobile communication shelter protection used in military units but also to any part of the protection structure.

In addition, it is natural that the EMP protective aluminum panel A of the present invention can be applied to any of the protective structures in addition to the composite panel B.

Hereinafter, the aluminum panel A for electromagnetic wave protection according to the present invention will be described with reference to specific examples.

(Example 1)

First, a 1.6 mm diameter nickel-iron-molybdenum alloy wire was heated at a temperature of 1,050 ° C. for 3 hours and 30 minutes in a hydrogen atmosphere of a general furnace, and air cooled (forced cooling) using a blower in a furnace for 4 hours.

The first processed 0.6 mm thick aluminum panel surface was then washed with acetone. And a roughness layer was formed on the surface of the aluminum panel using the blasting machine. Sand was used as fine particles of the blasting machine.

Then, a metal coating layer was formed to a thickness of 120 μm using a wire made of a nickel-iron-molybdenum alloy with an electric arc sprayer on the surface of the aluminum panel on which the roughness layer was formed. At this time, the arc heat of the electric arc sprayer was up to 4,100 ℃, the injection speed of the compressed air is 150m / sec. Respectively.

Here, as the electric arc spraying machine was used a spraying machine of Castolin Eutectic company of the specifications as shown in Table 1 below, the coating was performed by reciprocating four times from the top of the aluminum plate to the bottom.

Specification of Electric Arc Sprayer division Specification Input power 22V / 380V / 440V, 50 ~ 60Hz 3 Phase (Optional Use) Output voltage 50V (DC) max Current Up to 350 Amps Required air volume 1.56㎥ / min @ 6bar Injection volume 8 ~ 36Kg / hour

(Example 2)

In the same manner as in Example 1, the thickness of the metal coating layer was 160㎛.

For the panels of Examples 1 and 2 produced by the above method, the thickness and coating state of the metal coating layer, whether the aluminum panel was deformed, and the adhesion between the aluminum panel and the metal coating layer were examined.

First, as a result of inspecting the panel cross section of Example 1 and Example 2, the metal coating layer was formed on the surface of the aluminum panel of Example 1 to a thickness of 120㎛, Example 2 was formed of a metal coating layer of 160㎛ thickness Both panels showed good coating condition and surface roughness, so there was no problem in electromagnetic coupling between materials, and the bending deformation of the base aluminum panel was negligible. In addition, the adhesive strength between the aluminum panel and the coating layer was also excellent, confirming that there is no problem in use.

And the composite panel was manufactured using the said Example 1 and Example 2.

(Composite Panel Using Example 1)

The aluminum panel having a thickness of 0.6 mm was prepared together with the panel of Example 1 prepared and tested by the above method. And sandwich composite panel was prepared by filling a polyurethane rigid insulation material between the two panels to a thickness of 30mm. At this time, the metal coating layer of the panel of Example 1 was positioned to the heat insulating material side.

(Composite Panel Using Example 2)

The panel of Example 2 also constituted a composite panel in the same manner as the panel of Example 1.

(Comparative Example 1)

In order to compare the protection performance with the composite panel without electric arc spray coating, two sheets of 0.8 mm thick aluminum sheet were prepared, and sandwiched between 30 sheets of polyurethane rigid insulation between the two sheets of aluminum sheet. Was produced.

And the magnetic field protection rate of the composite panel and the comparative example 1 using Examples 1 and 2 were measured. The electromagnetic pulse magnetic field protection rate measurement method according to the IEEE STD 299, MIL-DTL-83528C, using a loop antenna, a signal generator, an RF amplifier, an EMC analyzer, etc. , The range of the frequency 100KHz ~ 20MHz at 0.6m distance was measured.

The formula for the protection rate is SH = 20 log 10 H1 / H2, where H1 is the intensity of the magnetic field measured in A / m when measuring the reference level, and H2 is the intensity of the magnetic field measured in the presence of the protection target in A / m. )to be. The unit of protection rate is dB.

Therefore, 60dB protection rate means 99.9% protection of incident electromagnetic pulse.

Table 2 below shows the test results of measuring the magnetic field protection rate of the composite panel and Comparative Example 1 using Example 1 and Example 2 according to the present invention.

Magnetic field protection rate (unit: dB) of the composite panel using Example 1 and Example 2 and Comparative Example 1 division Composite panel using Example 1 Composite Panel Using Example 2 Comparative Example 1 150 K Hz ≥56 ≥62 ≥41 1M Hz ≥62 ≥62 ≥55 14M Hz ≥60 ≥60 ≥60

As can be seen in Table 2, as a result of examining the protection rate of the composite panel using Example 1 and Example 2, it can be seen that Example 2 improves the electromagnetic pulse protection rate for the magnetic field compared to Example 1. This means that the thicker the metal coating layer, the better the electromagnetic pulse protection rate. In particular, in the case of Example 2, it can be seen that the magnetic field protection rate at 150 KHz is very excellent, 62 dB (99.92% protection) or more.

In addition, the panel of Comparative Example 1, which was conventionally used, had a protection ratio of 41 dB at 150 KHz, but the composite panel of Example 2 had a significantly improved protection rate of 60 dB or more at 150 KHz. It was confirmed that this satisfies the electromagnetic pulse protection requirements for the communication shelter used in military units. In addition, it was confirmed that there is no problem to use because the mechanical impact strength and durability is also good.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the present invention is not limited to the disclosed exemplary embodiments. It will also be appreciated that many modifications and variations will be apparent to those skilled in the art without departing from the scope of the present invention.

1: aluminum panel 2: roughness layer 3: metal coating layer
10: aluminum panel 20: polyurethane insulation
30: blasting machine 31: fine particles
40: electric arc sprayer 41: wire guide
42: torch tip W: wire

Claims (6)

(a) removing oil and foreign matter from the aluminum panel (1),
(b) blasting the surface of the aluminum panel 1 to remove oxides and to form a roughness layer 2;
(c) arc spraying the wires W on the roughness layer 2 of the aluminum panel 1 to form a metal coating layer 3,
The thickness of the aluminum panel 1 is 0.5 ~ 1mm,
The metal coating layer (3) is a thermal spray coating method of the aluminum panel for electromagnetic pulse protection, characterized in that formed in a thickness of 100 ~ 300㎛.
The method of claim 1,
In the step (c), the wire (W) has a diameter of 1.0 to 3.2 mm, spraying the wire (W) at an arc heat of 3,000 ~ 5,000 ℃ and a compressed air injection speed of 100 ~ 200m / sec. Spray coating method of aluminum panel for electromagnetic pulse protection.
3. The method according to claim 1 or 2,
The adhesive strength of the aluminum panel (1) and the metal coating layer (3) is a spray coating method of the aluminum panel for electromagnetic pulse protection, characterized in that the 4,500 ~ 8,000 psi.
3. The method according to claim 1 or 2,
The wire (W) is cobalt (Co), nickel (Ni), iron (Fe), nickel-cobalt alloy, nickel-iron alloy (Permalloy), nickel-iron-molybdenum alloy (Supermalloy) and nickel-iron-copper alloy Is any one of (Mu-metal),
The wire (W) is heated in a hydrogen atmosphere at a temperature of 900 ~ 1,100 ℃ for 2 to 4 hours, it is by air cooling for 4 to 5 hours, characterized in that the spray coating method of the aluminum panel for electromagnetic pulse protection.
The roughness layer 2 is formed on the surface of the aluminum panel 1, the metal coating layer 3 by arc spraying of the wire W is formed on the roughness layer 2,
The thickness of the aluminum panel 1 is 0.5 ~ 1mm,
Aluminum panel for electromagnetic pulse protection, characterized in that the thickness of the metal coating layer (3) is 100 ~ 300㎛.
6. The method of claim 5,
The aluminum panel (1) and the metal coating layer (3) has an adhesive strength of 4,500 ~ 8,000 psi, characterized in that the electromagnetic pulse protection aluminum panel.

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