JPH03188280A - Method for coating metal strip with molten metal - Google Patents

Abstract

PURPOSE:To easily and accurately carry out molten metal plating giving a fine structure and ensuring uniform coating weight by successively melting a solid metal material for plating, atomizing the molten metal with ultrasonic waves and sticking the resulting mist to a travelling metal strip. CONSTITUTION:A platelike metal material 2 for coating is guided upward in a feeder 1A through the guide part 4 and melted by heating with a heater 6 to form a melt reservoir 12 in the top opening 5. Ultrasonic waves are generated with an ultrasonic generator 3 composed essentially of an oscillator 8, a resonator 10 and a converging cover 11. The generated ultrasonic waves are obliquely radiated on the opening 5 to atomize the molten metal in the reservoir 12. The resulting mist 13 is allowed to flow toward a steel strip S by feeding a carrier gas as required and the mist 13 is stuck to the surface of the strip S as a coating film. The coating weight of the coating film can accurately be regulated by controlling the feeding rate of the metal material 2 for coating and the intensity of the ultrasonic waves.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method by which the surface of a metal strip can be continuously plated without using a molten metal bath.

[Conventional technology]

Conventionally, as a method for forming a plating film on the surface of steel strip,
Hot-dip plating is a widely used method in which a copper strip is immersed in pre-molten plating metal.

In continuous hot-dip galvanizing, which is a typical example of this type of plating method, the steel strip is heat-treated and surface-cleaned in a pretreatment furnace, then immersed in a hot-dip zinc bath to form a coating film, and then pulled out of the bath. The removed copper strip is then subjected to surface conditioning such as adjusting the amount of plating deposited by gas throttling and galvanizing.

The hot-dip plated steel sheet thus obtained has a relatively beautiful surface and excellent corrosion resistance, so it is widely used in practical applications.

[Problem to be solved by the invention]

However, conventional hot dip galvanizing methods have various problems associated with the use of plating baths. Particularly recently, plated steel strips are required to have a more uniform, smooth, and beautiful surface than ever before, mainly for use in home appliances, automobile exterior panels, etc. There is also a high demand for new products such as, and as a result, problems with the quality of plated steel strips and the plating process itself using conventional hot-dip plating methods have become apparent. Some of such problems are discussed below.

(1) Fe from the surface of the steel strip may be eluted into the plating bath,
Dross often occurs due to oxidation of the plating metal, and this must be pumped up and removed.
A loss of plated metal other than that attached to the copper strip occurs.

(2) Impurities are likely to be mixed in the plating bath, such as dross generated in the plating bath or debris from the bricks that make up the pot mixed into the bath, and these will adhere to the copper strip and deteriorate its appearance. .

(3) Since the components of the plating metal ingots put into the bath are different from the trace elements in the components that adhere to the steel strip and components discharged outside the bath as by-products such as dross, the necessary elements are contained as per the target. It is difficult to adjust and control the plating bath components.

As a result, various plating defects occur, such as poor plating adhesion and poor alloying of the galvanic material.

(4) It is necessary to immerse steel mechanical parts such as rolls for threading the copper strip, roll support arms, bearings, etc. in a high temperature, highly corrosive plating metal bath.

This causes problems such as erosion of these members, generation of dross accompanying this, and deterioration of the appearance of the plating surface due to erosion of the surface of the roll in the bath.

Furthermore, operation downtime is required to periodically repair or replace eroded or damaged parts of these mechanical parts, making it impossible to effectively and maximally utilize the production capacity of the equipment.

(5) By using a threading roll in the plating bath,
The group grooves of the rolls are easily transferred to the plating surface, resulting in deterioration of the appearance.

(6) Discharging bottom dross that accumulates at the bottom of the bath, and discharging top dross that accumulates on the bath surface.

Work in the vicinity of a high-temperature, large-volume plating bath, such as the initial threading of a steel strip into a bath and the maintenance of rolls during plating, places a heavy burden on the worker and is dangerous.

(7) Pot - Since only one type of plating can be performed per base, when performing various types of different plating, it is necessary to practice by pumping out the bath, or prepare a pot in which different types of plating metals are melted, and then It is necessary to carry out work such as moving the

(8) When producing double-sided plated materials and single-sided plated materials in a single facility, it is necessary to change the plating equipment for the pot part.
In addition to the burden on the equipment, a lot of time and effort are required for switching.

(9) It is difficult to perform special plating such as double-sided dissimilar plating, multilayer plating, and double-sided differential thickness plating.

In contrast to such conventional hot-dip plating methods, JP-A-61-2
In No. 07555, etc., a nozzle is brought close to the surface of the running steel strip, and the molten metal supplied from the molten metal tank is sucked out from the nozzle by the wet adhesive force between the molten metal and the surface of the copper strip, and is attached to the copper strip. A solid plating method has been proposed.

This method applies coating technology for high-viscosity paint, etc., but the molten metal is fed from the molten metal tank to the nozzle, and the amount of plating deposited is controlled by the head pressure of the molten metal tank. Therefore, a change in the height of the bath surface in the tank results in variations in the amount of plating deposited, and this has the disadvantage of poor accuracy in the amount of plating deposited. Furthermore, in any case, since a molten metal bath corresponding to an immersion type plating bath is required, there are various problems as described above.

As described above, conventional hot-dip plating methods have various problems.

The present inventors have developed a method for such conventional hot-dip plating methods.
He devised a new plating method that did not require a molten metal bath at all, and proposed this as Japanese Patent Application No. 103302/1982 and Saraniha Japanese Patent Application No. 264087/1983.

In the former method, a solid-phase plated metal material is continuously fed toward the surface of the copper strip through which the sheet is passed, and the tip side of the plated metal material is heated to melt copper by a heating melting device facing the copper strip. The copper strip is sequentially melted just before the surface of the copper strip, and the molten plating metal is continuously attached to the surface of the copper strip as a plating film.

In addition, in the latter method, the solid-phase plated metal material that is continuously supplied is sequentially melted from the tip side near the copper strip through which the plate is passed, and the plated metal material is applied to the hot-dip metal in the direction of the copper strip. The hot-dip plated metal is atomized by blowing high-temperature gas at a temperature higher than the melting point of the metal, and the atomized hot-dip plated metal is deposited as a plating film on the copper strip through which the plate is passed.

These methods melt the plating metal just before plating and deposit this molten metal as plating metal, and do not require a molten metal bath at all, so they solve the conventional problems associated with the use of plating baths. Furthermore, by controlling the feeding speed of the solid-phase plated metal material, there is an advantage that the amount of plating deposited can be controlled with high precision.

However, in the former plating method, the amount of plating metal supplied from the nozzle is determined by the gap between the nozzle tip and the plate surface, so the gap between the nozzle tip and the copper strip surface is approximately equal to the thickness of the plating film. It needs to be very fine.

However, it is difficult to maintain a constant minute gap between the plated copper strip and the nozzle because it is unavoidable that the copper strip undergoes some vibration during passing, and the shape of the strip may be defective.
This may lead to problems such as uneven plating thickness and collision between the nozzle and the plate.

In addition, the latter plating method does not cause the above problems because the gap between the nozzle and the plate surface is relatively wide, but it not only requires a large amount of gas to atomize the molten metal, but also requires a large amount of gas to atomize the molten metal. Since the diameter of the droplets of the molten metal is large, it is difficult to obtain a plated film with a fine structure, and the plated film has the disadvantage of poor workability, particularly press workability.

In view of these problems, the present invention makes it possible to continuously apply hot-dip plating to a metal strip without using a conventional molten metal bath, and also enables highly accurate control and uniformity of the coating amount. The present invention aims to provide a new plating method that allows a plating film with an even finer structure to be obtained.

[Means to solve the problem]

Therefore, the first invention of the present application sequentially melts the continuously supplied solid-phase plated metal material in the vicinity of one metal strip, and atomizes the hot-dip plated metal using ultrasonic waves. A feature of this method is that a plating film is formed by attaching minute droplets produced by oxidation to a metal strip passing through the plate.

Further, the second invention of the present application is characterized in that, in the above configuration, the ultrasonic waves are radiated to the hot-dip plated metal in a pressurized atmosphere.

According to the present invention, the plating metal material of the same phase is melted by the plating area weight immediately before plating, and this is plated on the metal strip through which the plate is passed, making it extremely easy to handle the plating metal and control the coating amount. In addition, since the molten plated metal is atomized using ultrasonic waves, very fine molten metal droplets (particle size of several tens of μm) are obtained.
Therefore, a plating film with a fine structure can be formed. Furthermore, since the distance between the plating metal supply device and the metal strip to be passed through can be relatively wide, a uniform plating film can be obtained without being affected by vibrations of the plate or the like.

In addition, when emitting ultrasonic waves to hot-dipped metal in a pressurized atmosphere, the high gas density makes it possible to sufficiently increase the transmission efficiency of the ultrasonic waves. Can be atomized. [Example] Figure 1 shows an example in which the method of the present invention is applied to continuous plating treatment of copper strips, and shows a heating melting mechanism for plated metal material, an upward opening for supplying hot-dip plated metal, and Using a plated metal supply device having a plated metal material supplying device, the solid phase plated metal material is sequentially fed in the direction of the opening within the device and sequentially melted from the tip side just before the opening by the heating melting mechanism, and ultrasonic waves are applied to the hot-dip plated metal. It is made to atomize by applying it, and the minute droplets are made to adhere to the copper strip passing through the plate.

In the figure, (IA) is a plating metal material supply device, (2)
1 is a plated metal material, (3) is an ultrasonic generator, and (S) is a copper strip through which the plate is passed.

The plated metal material supply bag M (LA) has a guide part (4) for guiding the same phase (plate-shaped in this example) plated metal material (2) upward, and the guide part (4) has an opening (5) at its tip (upper end) for forming a liquid reservoir of molten plated metal.

In this embodiment, the guide part (4) is composed of a cylindrical body with an elongated cross section, and a heating element (6) (heater) for melting the plated metal material is installed at the tip side of the guide part (4). etc)
A heating melting mechanism is provided.

The plated metal material supply bag N (IA) has a feeding mechanism (not shown) consisting of a feeding roller or a cylinder device, etc. in order to feed the solid phase plated metal material (2) toward the upper opening. are doing.

The ultrasonic generator (3) includes a high frequency power source (7), a vibrator (8), an amplitude expander (9) (horn), and a resonator (10).
) and a radial direction converter (11) for ultrasonic focusing provided to surround this resonator (10) (focusing cover)
It consists of

In the radiation direction converter (11), since the vibrations of the resonator (10) have opposite phases on the vibrator side and the anti-vibrator side, the radiation direction converter (11) overlaps the radiated sound waves with the opposite phases in the same phase on the surface of the liquid reservoir. It is arranged above the guide opening on the side opposite to the strip so that ultrasonic waves can be radiated into the opening (5) obliquely from above.

The radiation direction converter (11) has a parabolic reflecting surface in order to appropriately focus the ultrasonic waves on the molten metal liquid surface.

Further, the resonator (10) needs to be made of a material that has small internal loss, large resonance sharp particles, and high fatigue strength. As a material that meets these conditions,
Titanium alloys or aluminum alloys are preferred. This resonator (
10) A sound wave is radiated into the atmospheric gas by the vibration.

In this example, the copper strip (S) is supplied by the plating metal material supply device (I).
Thread the side of A) upward. In the guide section (4) of the plated metal material supply device (IA), the solid phase plated metal material (
2) are sequentially sent in the direction of the upper opening. Immediately before the opening, the melted metal is sequentially melted from the tip side, and the hot-dip plated metal forms a liquid reservoir (12) within the opening (5). This liquid reservoir (1
Ultrasonic waves are emitted from the ultrasonic generating device (3) toward the liquid surface in step 2), and the hot-dip metal in the liquid reservoir (12) is atomized into minute droplets due to the action of the ultrasonic waves.

That is, in the ultrasonic generator (3), the high frequency power source (7
) to vibrate the ultrasonic vibrator (8).

A resonator (10) connected to a vibrator (8) via an amplitude expander (9) is vibrated. By appropriately selecting the frequency of this ultrasonic wave, the particle size of the fine metal powder can be changed. Ultrasonic waves are emitted by the vibration of the resonator (10) using the atmospheric gas as a medium. This radiated ultrasonic wave is transmitted to the liquid reservoir (12) by a radial direction converter (11) installed so that the ultrasonic waves are in phase and overlapped on the surface of the liquid reservoir (12).
2) is focused on the surface of When the focused ultrasound waves act on the surface of the liquid reservoir (12), capillary waves are created on the surface of the liquid reservoir (12), which overcome the surface tension and cause the micro droplets (13) to fly up from the surface of the liquid reservoir (12). let and,
In this example, since the ultrasonic waves are radiated into the liquid reservoir (12) at an appropriate angle from diagonally above on the opposite side of the copper strip (S), the generated micro droplets (13) are directed toward the copper strip (S). It flows and adheres as a plating film to the surface of the copper strip where it passes. The above microdroplet (13
) has a particle size of approximately several tens of μm, and the plating film formed by such droplets has a very fine structure compared to a plating film formed by gas atomization or the like.

In addition, in this embodiment, the carrier gas may be made to flow in the direction of the copper strip from the ultrasonic generator (3) side, thereby more reliably directing the micro droplets (13) in the direction of the copper strip (S). can lead. This carrier gas contains micro droplets (13
) to adhere to the steel strip surface in a molten state, it is preferable that the temperature is higher than the melting point of the plating metal.

Further, it is preferable to preheat the copper strip (S) to be plated before plating, so that droplets of the hot-dip plated metal attached to the copper strip are spread out on the surface of the copper strip, resulting in a smooth and uniform plating film.

Furthermore, the radial direction converter (11) of the ultrasonic generator (3)
(Focusing cover) may be either a spot type that focuses the ultrasonic waves at one point or a type that focuses the ultrasonic waves in a line. In the former case, the spot type radial direction converter (11) is In the latter case, a plurality of radial direction converters (11) are arranged along the width of the steel strip.

Furthermore, when ultrasonic waves are used under pressure, the density of the atmospheric gas becomes higher and the oscillation efficiency of the resonator (10) becomes better, so that the hot-dip metal can be atomized more efficiently. Therefore, by performing the process shown in FIG. 1 in a pressurized chamber, the plating process can be performed more efficiently. Details and examples will be described later.

According to the inventors' experimental results, using an ultrasonic generator (3) as shown in Fig. 1, an argon gas atmosphere with an absolute pressure of 1 kg/all'' and 9
, 9 kg/am'', and vibrated in a resonator with a frequency set to 100 kHz, with a single amplitude of approximately 16 μm. As a result, the vibrations were 170 dB and 170 dB near the surface of the molten metal pool, respectively. Ultrasonic waves with a sound pressure level of 190 dB were obtained. In this experiment, a titanium alloy was used as the resonator and an aluminum alloy was used as the molten metal. Then, this ultrasonic wave was applied to the surface of this aluminum alloy liquid reservoir. As a result, spherical particles with a particle size of 30 to 50 μm and an average particle size of 40 μm were obtained.

FIG. 2 shows another embodiment of the present invention. In order to guide the generated micro droplets (13) toward the surface of the copper strip using a carrier gas, A gas supply port (14) for carrier gas is provided.

According to such a configuration, micro droplets generated by ultrasonic radiation to the liquid reservoir (12) are transported to the gas supply port (1) on the side of the opening.
The carrier gas from step 4) is guided toward the copper strip, and the copper strip is reliably attached to the surface of the copper strip.

In this example, since a carrier gas is used, the radial direction converter (11) of the ultrasonic generator (3) is connected to the liquid reservoir (1).
2), and ultrasonic waves are applied perpendicularly to the liquid surface, but the invention is not necessarily limited to this. For example, as shown in FIG. 1, ultrasonic waves may be applied from an oblique direction.

Note that other conditions and the like are the same as those described in the embodiment shown in FIG.

Figure 3 shows the plating metal material (2) supplied by the plating metal material supply device (IC) being melted into the opening by a heating device (15) (heater etc.) installed outside the opening. A liquid reservoir (12) of plated metal is formed, and ultrasonic waves are radiated into this liquid reservoir (12).

In this embodiment, the plated metal material supply device (IC) is provided with a preheating mechanism consisting of a heating body (6') (heater, etc.) for preheating the plated metal material on the tip side of its guide part (4). It is being

Note that other conditions and the like are the same as those described in FIG.

Figures 4 and 5 show the guide section (4) for guiding the molten plated metal.
) through the opening (5) of the hot-dip metal flow (
16) is atomized by emitting ultrasonic waves, and Figure 4 shows that the plated metal material (2) is melted by the heating melting mechanism (heating body (6)) of the plated metal material supply device (ID). Figure 5 shows the plated metal material (2).
This is a type in which the liquid is melted by a heating device (15) facing the opening (5).

Note that other configurations, conditions, etc. are the same as in the embodiment described above.

The embodiment shown in FIG. 6 has a gas supply port (1) on the side of the opening (5).
7), and by blowing high-temperature gas at a temperature higher than the melting point of the plated metal material in the direction of the copper strip (S) from the gas supply port (17), the hot-dip plated metal discharged from the opening (5) is directed in the direction of the copper strip. This hot-dip metal flow (16
) is designed to emit ultrasonic waves.

Further, in the embodiment shown in FIG. 7, a gas supply port (17) is provided on the side of the opening (5), as in FIG.
By blowing high-temperature gas at a temperature higher than the melting point of the plated metal material in the direction of the copper strip from 7), the tip of the plated metal material (2) supplied from the opening (5) is melted, and the hot-dip plated metal is heated to the high temperature. The plating metal stream (16) is forced to flow in the direction of the copper strip using gas, and ultrasonic waves are radiated to this plating metal stream (16). In this embodiment, a plating metal material supply device (IG
) has a preheating mechanism similar to that shown in FIG. 3 in its guide portion (4).

As shown in Figures 6 and 7 above, by blowing high-temperature gas from the side of the opening, the melted state of the plated metal becomes uniform in the width direction, and the hot-dip plated metal is supplied in the width direction of the plate at a constant flow rate. can do. In other words, some degree of unevenness is unavoidable when melting plated metal materials, and for this reason, when hot-dip plated metal is allowed to flow naturally in the direction of the copper strip, the melting state becomes uneven and the flow rate of the metal flow etc. This becomes inconsistent and causes non-uniformity in the amount of adhesion in the horizontal direction (board line direction). In this respect, in the above embodiment, the metal melting is made uniform in the width direction by gas spraying and is controlled at a constant flow rate, so that uniform plating is possible. Further, in addition to the above-mentioned effects as in the embodiment shown in FIG. 7, the method in which high-temperature gas acts to melt the plated metal material can make the melting of the plated metal material more uniform.

The above-mentioned high-temperature gas is usually a gas whose temperature is below the boiling point of the plated metal material and about the melting point + (50 to 150)"C. For example, when the plated metal material is Zn, it is usually 500 °C. More than 1 gas force is used.

When hot-dip galvanizing a copper strip using these methods, it can be carried out under the following conditions, for example.

Zn plate (plated metal material) thickness: 5I Zn plate thermal temperature: 410°C High-temperature gas temperature: 550°C High-temperature gas flow rate: 5m/s Gas supply loss slit @: 5+om Note that in the embodiments shown in Figs. 6 and 7, Other conditions and the like are the same as in each of the above embodiments.

In the embodiments shown in FIGS. 8 and 9, the plating metal supply device (IH) (II) is arranged downward to allow the hot-dip metal to flow down naturally, and this hot-dip metal flow (16
), which emits ultrasonic waves from the side.
The figure shows a plating metal material supply device (IH) for plating metal material (2).
), and a type in which the plated metal material (2) shown in Fig. 9 is melted by a heating device (15) facing the opening (5). It is. Note that other configurations, conditions, etc.) are the same as those in the above-mentioned embodiments.

In the embodiments shown in FIGS. 10 and 11, the molten plating metal is flowed down along the slope guide (18) while being heated, and the molten plating metal flow (16) is electromagnetically applied on the slope guide (18). By applying a force, the metal flow is urged in the direction of flow and the slope guide (18
), and radiates ultrasonic waves to this metal flow.In this way, instead of letting the molten plating metal flow down as it is, it injects the hot-dip metal flow with electromagnetic force. By energizing and injecting the metal strip in the form of a film, it is possible to maintain a relatively wide distance between the plated metal material supply device and the metal strip to be passed through. Figure 10 shows a type in which the plated metal material (2) is melted by the heating melting mechanism (heating body (6)) of the plated metal material supply device (IJ).
Moreover, FIG. 11 shows a type in which the metal material (2) is melted by a heating device (15) facing the opening (5). is provided with a slope guide (18) for making the flow of hot-dip plating metal flow down, and this slope guide (18) is equipped with a heating body (19) for heating the plating metal flowing down.
) and a plating metal flow toward the copper strip (acceleration) by the action of electromagnetic force.

As this urging device (20), any suitable known means can be used, such as a traveling magnetic field type pump using a linear motor mechanism.

The guide surface (1) near the end of the slope guide (18)
80) is inclined slightly upward toward the copper strip, so that the hot-dip metal flow can be injected slightly upward toward the copper strip.

Note that other configurations, conditions, etc. are the same as in the above-described embodiment.

Each of the embodiments described above is a method in which the ultrasonic waves are focused by a radiation direction converter and radiated to the hot-dipped metal, but in some cases, an amplitude expander (9) is used as shown in FIG. The vibrating portion (21) at the tip of the vibrating portion (21) may be immersed in the liquid reservoir (12), thereby atomizing the hot-dip plated metal.

FIG. 13 shows an embodiment in which atomization of hot-dip plated metal by ultrasonic waves is carried out in a pressurized atmosphere, in which an ultrasonic generation bag W (3) and a plated metal material supply device (IA) are used.
is disposed within a chamber (22), and the inside of the chamber (22) is maintained at a pressurized state equal to or higher than atmospheric pressure by a pressurizing means.

As mentioned above, under such pressurized conditions, the density of the gas is high, so the transmission efficiency of the ultrasonic waves focused on the hot-dip plated metal (12) is high, making it possible to efficiently atomize the hot-dip plated metal. . As a result, compared to plating under atmospheric pressure,
Even if ultrasonic waves are radiated under the same conditions, a larger amount of plating can be obtained. The table below shows Zn as a plating metal material.
This study investigated the difference in the amount of plating deposited when plating was performed under atmospheric pressure and under pressure, and according to this research, when ultrasonic waves were emitted under the same conditions, However, in the present invention, there is no restriction on the direction in which the copper strip is passed. That is, in each of the above embodiments, the copper strip is threaded upward, but it may be threaded downward, diagonally, or in some cases horizontally.

Of the methods of each embodiment described above, the method shown in FIG.
In the method shown in Figure 0, the molten plated metal does not form a liquid reservoir in the Sekiguchi (5), so the molten metal gets inserted between the inner wall of the guide and the plated metal material, interfering with the continuous supply of the plated metal material. It is possible to appropriately avoid troubles such as causing problems.

Further, the plating film formed as described above may have slight unevenness in the amount of adhesion, and in order to make this unevenness uniform, a uniforming treatment can be performed using a surface conditioning device. As this surface conditioning device, for example, a conventional gas throttle nozzle type device, an ultrasonic vibration type device having an ultrasonic vibrator (so-called ultrasonic iron), etc. are used.

In addition, the plating process according to the present invention also improves the wettability of the plating,
To ensure adhesion, a non-oxidizing atmosphere (e.g. H2
:5 to 25%, N2: 80 to 95%). Also in the method of the present invention, it is preferable that the surface of the copper strip be as clean as possible before plating.

The plating method according to the present invention can be applied to various metal or alloy platings, for example, Zn plating on copper strips, A
In addition to l-Zn alloy plating, Co-Cr-Zn alloy plating (e.g. 1%Co-1%Cr-Zn alloy plating), Al-Mg-Zn alloy plating (e.g. 5%A
l-0,6% Mg-Zn alloy plating), Al-5i-Z
n alloy plating (e.g. 55% Al-1, 6% 5i-Z
n alloy plating), 5i-A1 alloy plating (e.g. 10
%5i-A1 alloy plating), 5n-Pb alloy plating (for example, 10% Sn-Pb alloy plating), etc.

In addition, in the above embodiment, the plating metal material (2) is supplied only to one side of the copper strip (S), but in the case of double-sided plating of the steel strip, the device (1) is supplied to both sides of the copper strip. It goes without saying that the plates are placed on each surface and plating is performed on each surface. In this case, plating on both sides does not need to be performed at the same position in the line direction.

In addition, when plating both sides of the steel strip in the method of the present invention,
By arranging plating metal materials (2) having different compositions on both sides of the copper strip, double-sided dissimilar plating can be easily performed. For example, a steel plate having an Fe-Zn alloy plating film on one side (painted surface) and a Zn plating film on the other side (bare surface) can be obtained as an outer panel material for home appliances and the like.

In each of the above embodiments, a plate-shaped plated metal material (2) was used, but a powder-shaped material, for example, may be used instead. Even in this case, the plated metal material (2) is filled in the guide portion (4) and sent toward the nozzle by a suitable feeding means.

〔Effect of the invention〕

According to the present invention described above, a plating film made of molten metal can be continuously formed on a metal strip without using a molten metal bath, and the following advantages are obtained compared to the conventional method using a plating bath. It will be done.

(1) Since there is no dross generated when a plating bath is used, there is no loss of plating metal other than adhesion to the copper strip.

(2) Dross, impurities, etc. do not adhere to the surface, and the appearance is kept beautiful.

(3) Since the plating metal is directly welded, almost the same components as the plating metal material are plated, and the components in the plating film are made uniform, and the components can be easily controlled.

(4) There is no need to use parts immersed in a bath, and therefore there is no need to stop operations to repair or replace eroded machine parts.

(5) Since there is no need to use rolls in the bath, there is no deterioration in appearance due to transfer of roll groups.

(6) Eliminates the need for discharging bottom dross and top dross, threading steel plates into the bath, and cleaning the rolls in the bath.
The burden on workers is significantly reduced.

(7) When performing various alloy platings, it is only necessary to replace the plating metal material supplied to the copper strip, and there is no need for major work such as changing baths or moving pots, so it is easy to perform various types of plating. plating is possible.

(8) Single-sided plating, multilayer plating,
Various types of plating, such as double-sided differential thickness plating and double-sided dissimilar plating, can be easily performed.

In addition to these advantages, handling of the plating material is extremely easy because the solid-phase plating metal material is fed, melted just before the plating area, and then adhered to the metal strip. In addition, the amount of plating deposited can be controlled by the feeding speed of the solid-phase plated metal material, and therefore a high degree of accuracy in the amount of plating can be ensured.

Furthermore, since the present invention atomizes the molten plated metal material by the action of ultrasonic waves, it is possible to obtain extremely fine droplets of hot-dip plated metal compared to conventional gas atomization, which can be attached to the surface of the metal strip. As a result, a plating film that is extremely dense and has excellent workability, particularly press formability, can be obtained.

The method of the present invention also has the advantage of not requiring a large amount of gas unlike gas atomization.

Furthermore, the distance between the plated metal material supply device and the metal strip to be passed through can be kept relatively wide, and a uniform plating film can be obtained without being affected by vibrations of the plate, and collisions between the plate and the nozzle. Such troubles can be appropriately prevented.

Further, according to the invention of the cylinder 2 of the present application, in addition to the above-mentioned effects, a large amount of plating can be obtained and thick plating can be easily performed.

[Brief explanation of drawings]

1 to 13 are explanatory diagrams showing embodiments of the present invention, respectively. In the figure, (IA) to (ratio) fitting metal material supply device, (2) fitting metal material, (3) ultrasonic generator, (
5) is the opening, (12) is the liquid reservoir, (13) is the minute droplet, (
16) is a hot-dip metal flow, and (S) is a copper strip. g! %1Figure 4Figure 8Figure 0Figure 11Figure 2

Claims (2)

[Claims] (1) Continuously supplied solid-phase plated metal material is sequentially melted near the metal strip through which the plate is passed, and this hot-dip plated metal is atomized by ultrasonic waves to form minute droplets due to the atomization. A method for hot-dip metal plating of a metal strip, characterized by forming a plating film by adhering it to the metal strip to be passed. (2) The method for hot-dip metal plating of a metal strip according to claim (1), characterized in that the hot-dip plated metal is atomized by radiating ultrasonic waves to the hot-dip plated metal in a pressurized atmosphere.