ALLOY-COATED STEEL SHEET AND METHOD OF MANUFACTURING SAME

Hereinafter, one embodiment of the present invention detailed the on-sensors other. But, this is by way of example number so that when, the range of the present invention is defined by the present invention refers to one category number 802.11a packets not [...] claimed only disclosed.

In the absence of the other definitions for all terms used in the present invention (including the techniques and the treatment) is specification is provided to common sense can be understood to a person with skill in the art can be used in to are disclosed. The entire specification of any components that "comprising" when any portion, particularly the opposite substrate [...] number but without other components further can include other components which means that the other. In addition flow may be not specially mentioned in phrase a plurality type comprises a unit.

In addition, wherein the arbitrarily for facilitating description size and thickness of each configuration exhibited drawing representing, not limited to the present invention are not necessarily shown.

The entire specification, layer, film, region, such as "upper" or part of any other portions of the plate determines, determines when "on -", "directly on" as well as any other portion when intermediate when another portion comprises a unit.

The entire specification, layer, film, region, such as "upper" or part of any other portions of the plate determines, when "- on" in two lines, of means in which is located above or below the object, meaning that the gravity direction must reference phase is positioned on are not correct.

The entire specification, without significantly definition is that, the "A layer", as well as corresponding layer is composed only when A, A comprises including a also be the case.

The entire specification, without significantly definition is that, "A non-B alloy layer" is, as well as when A-a B alloy composed of only a corresponding layer, including A a-B alloy comprising also be the case.

The entire specification, without significantly definition is that, "A provided B provided C alloy layer" is, as well as alloy composed of only a corresponding layer when A provided B provided C, including alloy comprising A a-B provided C also be the case.

Recently, pipeline and ceramic joint body having a convenient door number point said background art in order to solve silicon containing ceramic joint body magnesium corrosion-resistance studies of sacrificial corrosion resistant with a screw thread the progressing disclosed.

In one example, molten plating steel sheet number plated steel sheet excellent corrosion-resistance coating Al provided Mg a-Si high pressure liquid coolant bath study number than conventional flow tides. However hot dip manner when tank number, number Mg content that is limited opposite side and 20 g/m² Hereinafter gambler clothes of silk brocade corrosion resistance when the movement of the motor are disclosed. In addition, Mg₂ Si alloy different compressed material acting as the inside and outside of the narrow range but are known to 6% when only a single door number Mg flow tides. Plated steel plate has Mg Al provided Mg a-Si₂ The metal plating layer formed an excellent corrosion-resistance Si phase having known. Mg₂ In area ratio Si phase is plating 0. 5% or more, and 30% hereinafter, Mg₂ When the girdle 10 micro m hereinafter Al provided Mg a-Si Si on corrosion resistance of steel plate at first plating wirelessly reports corrosion disclosed. However, hot-dip method which contacts a limitation on number Mg content of plated steel plate has small number Al provided Mg a-Si is small (about 15% or more) so that the number of constant content or more Mg content over a small number plated steel sheet having Al provided Mg a-Si for hereinafter uninhabitable.

In another example, aluminum-coated substrate 350 °C or more in a vacuum, heating and 500 °C hereinafter in a photoresist layer forming method Mg Al provided Mg alloy layer a d flip-flow tides. But the evaporated heating method in which the substrate is depositing Mg is generated vapor loss can be subjected to accurate alloy phase changing the characteristics of the material number Al provided Mg a-Si layer according to a normally hard to door number when flow tides.

The present invention refers to the above-described ceramic joint body having a convenient door number point and, in order to solve the device number point that door Al provided Mg alloy steel sheet, melting method since the present invention refers to Mg physical vapor deposition coated steel sheet on an opposite side in a variety of coating layer coating layer does not limit number Al provided Mg a-Si Mg content less number structure operable to disclosed.

Specifically, silicon containing ceramic joint body magnesium sacrificial corrosion resistant alloy coating film formed through deposition of the multilayer type heat imparted to simultaneously, even thin steel sheet having a high alloy coating can be [...] number characteristics.

Hereinafter, manufacturing method of the present invention in one embodiment according to alloy coated steel sheet and, number prepared by the alloy coated steel sheet is described substrate.

Of the present invention certain embodiments include, Al located on a steel sheet, and a plating layer including Si in aluminum plated steel sheet including the steps of; forming a coating layer coated on the aluminum plated steel sheet on said Mg Mg; and said Mg Mg said photoresist layer by the heat treatment of aluminum plated steel sheet coated with a process uses; a manufacturing method including a number of coated steel alloy [...] substrate.

Be said steel sheet is cold-rolled steel sheet. But, not limited are not correct.

Said aluminum plated steel plate has, ceramic joint body to be may be, total 100% by weight with respect to the plating layer specifically, Si: 8 weight % or more, and 10 weight % hereinafter; Al: 88 weight % or more, 90 weight % hereinafter; and a denial Fe can be made of glass.

In addition, the plated aluminum plated steel sheet, aluminum plated using predicted Al a-Fe a-Si alloy layer, and Al a-Si alloy layer can be, said alloy layers of hyperthermia Al a-Fe a-Si alloy layer, and Al a-Si alloy layer are removed to form can be. Said Al a-Fe a-Si alloy layer, morning fair number Al plated steel sheet, the steel sheet is in the metal plating layer to diffuse into an upstream where Fe Al a-Si can be.

Said coating on the aluminum plated steel sheet Mg; coating tends to, physical vapor deposition (PVD) that are performed may be disclosed. More specifically, physical vapor deposition (EML-a PVD) amount is carried out electromagnetic may be disclosed. Only, and not limited to, fabricating method of field emission device, device thermal vapor, sputtering source, cathode arc source such as the physical method Mg deposition if available, various method can be Mg coating has been employed.

Said method used in the heat treatment step, but by induction heating device, and not limited to, other suitable heat treatment means can. In addition, induction heating type heat treatment other than the manner of embodiment, thermally treated at temperature s402. heat treatment method.

Of Figure 1 device is, alloy coated steel sheet number [...] of continuous coating device can be used and production are disclosed. But, this tank only and not the limited number in one example of the method.

Said device is, in the air ceramic joint body (17) supplying steel sheet supply device (11), the magnetron sputtering source (Inverse Magnetron Source) that net reverse e in a vacuum and a nitrogen-pre-steel sheet (12), physical vapor deposition (physical vapor deposition: PVD) Mg after pre-coating device (13), and is discharged to the atmosphere is the heat treatment can be induction heating device (14), heat treated coated steel again rewinding steel sheet discharge device (15) consisting in the nanometer range. Physical vapor deposition device (13) comprises an electronic base amount (electromagnetic levitation; EML) can be sources disclosed. Reverse e that net magnetron sputtering source (12) on physical vapor deposition device (13) vacuum container (16) is disposed in the operating can be.

Said device manufacturing method using the exemplary alloy coated steel sheet, as follows. First, ceramic joint body (17) is provided and, said separating and rust on the surface of the steel sheet such as a stand-alone embodiment whether residual oil for other alkali number part of can.

Then, said steel sheet steel sheet supply device (11) while fed through a vacuum container (16) is supplied to the. Then, vacuum vessel (16) installed in reverse e that net magnetron sputtering source (12) embodiment can clean the surface is removed.

After clean, subsequently to the first transport steel, vacuum vessel (16) is disposed within the amount electromagnetic source (13) can be Mg Al through plating on vacuum coating.

After coating, the length of the steel sheet after transfer to discharge atmosphere, at least one out induction heating device (14) can be heat treatment temperature and at the same time.

Heat treatment is used for obtaining a feeding number continue to steel sheet can be prepared by the alloy coated steel sheet.

Hereinafter, the aforementioned manufacturing method by steel sheet prepared by the number is described substrate. Aspect of the coated steel sheet of the present invention has been found greatly are four divided by, the specification of the present invention number 1 to number 4 example embodiments implementing them in 2000. Hereinafter, embodiment of the present invention number 1 to number 4 it relates to 2000.

Number 1 embodiments

Figure 2 shows a coated steel sheet according to embodiments of the present invention number 1 also is a mimetic of alloy. The same through a browser, said manufacturing method according to embodiments of the present invention number 1 prepared by the number by alloy coated steel sheets, steel sheet (21); and said steel sheet (21) located on the Al provided Mg a-Si alloy layer (23); and, said Al provided Mg a-Si alloy layer (23) is, Al provided Mg alloy phase (24) composed of an alloy layer in, granular Mg a-Si alloy (25) can be formed as including.

Said alloy coated steel sheets, one or more mg for physical vapor deposition method on ceramic joint body since the higher magnesium content existing number bath method for hot dip coating process from small number Al provided Mg a-Si coating layer. Hot-dip method when the number bath Al provided Mg a-Si plated steel sheet, there are limit in the magnesium content of magnesium (about 15% or more) filled with a constant content or more plated steel sheet having less number Al provided Mg a-Si is to tame. This structure of the plating layer different from each present inside aluminum plating Mg a-Si alloy. The, granular Mg a-Si alloy phase dispersed uniformly distributed in the seed layers compressed material distributed outputs a degreasing process there are limit in the disclosed. In addition hot dip process since Mg content but number Al provided Mg alloy which does not easily generate Mg a-Si alloy is sufficient for generating position number going door number for generating flow tides.

While, said of the present invention number 1 embodiments according to alloy coated steel sheets, hot-dip method number it became work differently than the coating layer formed Mg a-Si alloy plating layer Al provided Mg alloy phase when there is a small number by means of which granular Al provided Mg a-Si coating layer, to carry in the embodiment which can be implemented as supporting [...] and sacrificial corrosion resistant properties.

More specifically, said Al provided Mg alloy phase, Al₃ Mg₂ And including a, said Mg a-Si alloy granules with, Mg₂ Including a Si may be disclosed. Said Al provided Mg alloy phase Al₁₂ Mg₁₇ Phase can be further.

Said Al such as₃ Mg₂ Phase including Mg in alloy layer₂ Si alloy layer is formed on the alloy kernel including Al provided Mg a-Si, which in the embodiment as sacrificial corrosion resistant plating is electrically carry from supporting corrosion resistance of steel plate can be improved. The, even in thin, can exhibit a high resistance to corrosion.

Said Mg a-Si alloy granules with, be monolithic the game. Mg a-Si alloy coating layer surface deterioration since large monolithic of cushion effect flow tides.

In addition, the content of granular Mg a-Si alloy in said Al provided Mg a-Si alloy layer, total 100% by weight with respect to said Al provided Mg a-Si alloy layer, 1 weight % or more, and can be one having 70 weight % hereinafter. If the monolayer Al provided Mg a-Si, Mg Mg a-Si alloy content of the alloy layer granular sufficient diffusion thereof can reach. If too little content of granular Mg a-Si alloy, the compressed material can be insignificantly. If too much content of granular Mg a-Si alloy, sacrificial corrosion resistant coating layer is selected from the light source consumed can be reduced corrosion and door number is generated.

Said alloy coated steel sheet, said steel sheet (21), and said Al provided Mg a-Si alloy layer (23) positioned between the Al a-Fe a-Si alloy layer (22) may be provided further including, as is aforementioned Al morning fair number plated steel sheet, where the metal plating layer to diffuse into the steel sheet is in Fe Al a-Si can be. Or, Mg Fe plating layer diffuse into the steel plate during a heat treatment following Al a-Si is in the metal layers of the timbre can be.

Al a-Fe a-Si alloy layer, and sequential manner prevents corrosion Al provided Mg a-Si alloy layer can be. As a result physical blocking type, or a single sacrificial corrosion resistant manner such as aluminum or zinc coating for preventing corrosion general excellent corrosion resistance than other characteristics.

In addition, said alloy coated steel sheet is, said Al provided Mg a-Si alloy layer located on the Mg Mg Al provided Mg alloy layer formed along further including diffusion layer or may be disclosed. The, sequential manner enhanced corrosion, can be excellent corrosion resistance characteristics.

Number 2 embodiments

Figure 3 shows a coated steel sheet according to embodiments of the present invention number 2 also is a mimetic of alloy. The same through a browser, said manufacturing method according to embodiments of the present invention number 2 prepared by the number by alloy coated steel sheets, steel sheet (21); said steel sheet located on the Al a-Si alloy layer (26); and said Al a-Si alloy layer (26) located on the Al provided Mg a-Si alloy layer (23); and, said Al provided Mg a-Si alloy layer (23) is, Al provided Mg alloy phase (24) in an alloy layer composed, granular Mg a-Si alloy (25) can be formed as including.

A description is said Al provided Mg a-Si alloy layer, said number 1 embodiment a pulverized product since the omit other.

Said Al a-Si alloy layer, Al hot dip steel plate and may be present, or said manufacturing method Al during a heat treatment in a diffusion surface direction and Si is newly formed can be.

The, Al a-Si alloy layer, and sequential manner prevents corrosion Al provided Mg a-Si alloy layer can be.

Further, said alloy coated steel sheet, said steel sheet (21), and said Al provided Mg a-Si alloy layer (23) positioned between the Al a-Fe a-Si alloy layer (22) may be provided further including, as is aforementioned Al morning fair number plated steel sheet, where the metal plating layer to diffuse into the steel sheet is in Fe Al a-Si can be. Or, Mg Fe plating layer to diffuse into the steel sheet during a heat treatment following Al a-Si is in the metal layers of the timbre can be.

The, Al a-Fe a-Si alloy layer, Al a-Si alloy layer, and sequential manner prevents corrosion Al provided Mg a-Si alloy layer can be. As a result physical blocking type, or a single sacrificial corrosion resistant manner such as aluminum or zinc coating for preventing corrosion general excellent corrosion resistance than other characteristics.

In addition, said alloy coated steel sheet is, said Al provided Mg a-Si alloy layer located on the Mg Mg Al provided Mg alloy layer formed along further including diffusion layer or may be disclosed. The, sequential manner corrosion resistance, can be excellent corrosion resistance characteristics.

In addition, the content of granular Mg a-Si alloy in said Al provided Mg a-Si alloy layer, total 100% by weight with respect to said Al provided Mg a-Si alloy layer, 1 weight % or more, and can be one having 50 weight % hereinafter. If too little content of granular Mg a-Si alloy, the compressed material can be insignificantly. If too much content of granular Mg a-Si alloy, sacrificial corrosion resistant coating layer is selected from the light source consumed can be reduced corrosion and door number is generated.

Number 3 embodiments

Figure 4 shows a coated steel sheet according to embodiments of the present invention number 3 also is a mimetic of alloy. The same through a browser, said manufacturing method according to embodiments of the present invention number 3 prepared by the number by alloy coated steel sheets, steel sheet (21); and said steel sheet located on the Al provided Mg a-Si alloy layer (23); and, said Al provided Mg a-Si alloy layer (23) is, alloy layer be a gradient of the presence Mg content (gradient).

Said alloy coated steel sheets, one or more mg for physical vapor deposition method on ceramic joint body since the number bath, differently than an opposite side does not limit number magnesium alloy layers prior art Al provided Mg provided Si content like magnesium distribution number [...] diffusion thermal treatment since the material to be less capable of various Al provided Mg a-Si alloy layers structure number 2000.

By Mg concentration according to present content of gradient Mg Al provided Mg a-Si layer with the presence of compressed material effect in various alloy can be different. Example Al various alloy₁₂ Mg₁₇ , Al₃ Mg₂ , Mg₂ Implementation being such as Si. This allow different Mg concentration gradient is formed on each alloy coated steel sheet according to the present different plied construction is delayed corrosion thereof can move upwards and downwards.

Specifically, the gradient of the (gradient) is Mg content in said Al provided Mg a-Si alloy layer, reducing said Al provided Mg a-Si alloy layer can be formed as inward direction from the surface.

Or, Mg (gradient) is the gradient of the content in said Al provided Mg a-Si alloy layer, said Al provided Mg a-Si alloy layer can be formed as inwardly from the surface increases.

Or, Mg content in said Al provided Mg a-Si alloy layer and becomes its maximum point, Mg (gradient) is the gradient of the content in said Al provided Mg a-Si alloy layer, said Al provided Mg a-Si alloy layer increased inward direction from the surface switches, said Mg content becomes its maximum point can be formed as a reduced from.

Or, said Al provided Mg-a Si alloy layer in inward direction from the surface alloy layer comprising constant content Mg content constant portion, said Mg content, content can be formed as is terminated at a constant from increasing.

Or, said Al provided Mg-a Si alloy layer in inward direction from the surface alloy layer comprising constant content Mg content constant portion, said Mg content, content can be formed as a constant and terminated at a is reduced from.

As aforementioned, manufacturing method of the present invention alloy coated steel sheet according to an opposite limit free magnesium distribution number magnesium content Al provided Mg a-Si alloy layers diffusion heat treatment or the like and it is possible to number [...] various alloy layers structure operable to smaller number and Al provided Mg a-Si, the Mg concentration uniform hot-dip steel differently from layered structure by appropriately-blocking type and number dielectric sacrificial corrosion resistant alloy layer in combination to maximize corrosion resistance can be styrofoam.

In addition, in the embodiment from which carry as supporting, S. corrosion resistant characteristics.

Said alloy coated steel sheet is, although not shown in fig. 4, said steel sheet, and said Al provided Mg a-Si alloy layer positioned between the layer contains hollow beads can Al a-Si alloy.

Said Al a-Si alloy layer, Al hot dip steel plate and may be present, or said manufacturing method Al during a heat treatment in a diffusion surface direction and Si is newly formed can be.

The, Al a-Si alloy layer, and sequential manner prevents corrosion Al provided Mg a-Si alloy layer can be.

Further said alloy coated steel sheet, said steel sheet (21), and said Al provided Mg a-Si alloy layer (23) positioned between the Al a-Fe a-Si alloy layer (22) may be provided further including, as is aforementioned Al morning fair number plated steel sheet, where the metal plating layer to diffuse into the steel sheet is in Fe Al a-Si can be. Or, Mg Fe plating layer to diffuse into the steel sheet during a heat treatment following Al a-Si is in the metal layers of the timbre can be.

The, Al a-Fe a-Si alloy layer, Al a-Si alloy layer, and sequential manner prevents corrosion Al provided Mg a-Si alloy layer can be. As a result physical blocking type, or a single sacrificial corrosion resistant manner such as aluminum or zinc coating for preventing corrosion general excellent corrosion resistance than other characteristics.

In addition, said alloy coated steel sheet is, said Al provided Mg a-Si alloy layer located on the Mg Mg Al provided Mg alloy layer formed along further including diffusion layer or may be disclosed. The, sequential manner corrosion resistance, can be excellent corrosion resistance characteristics.

In addition, said alloy coated steel sheet Al provided Mg a-Si alloy layer, an alloy layer in Al provided Mg alloy phase, including granular Mg a-Si alloy can be formed as.

In addition this type which contribute to improve corrosion resistance, in particular aforementioned efined building.

Number 4 embodiments

Figure 5 shows a coated steel sheet according to embodiments of the present invention number 4 also is a mimetic of alloy. The same through a browser, said manufacturing method according to embodiments of the present invention number 4 prepared by the number by alloy coated steel sheets, steel sheet (21); and said steel sheet located on the Al provided Mg a-Si alloy layer (23); and, said Al provided Mg a-Si alloy layer (23) in Mg content, total 100% by weight with respect to said Al provided Mg a-Si alloy layer, can be greater than the 15% by weight. More specifically 15 weight % or more, and can be one having 90 weight % hereinafter.

Said alloy coated steel sheets, one or more mg for physical vapor deposition method on ceramic joint body since the higher magnesium content existing number bath method for hot dip coating process from small number Al provided Mg a-Si coating layer. Hot-dip method when the number bath Al provided Mg a-Si plated steel sheet, there are limit in the magnesium content of magnesium (about 15% or more) filled with a constant content or more number of zinc coated steel having Al provided Mg a-Si oxide to tame.

While, said of the present invention number 4 embodiments according to alloy coated steel sheets, hot-dip method it became work differently than an opposite side does not limit the number Mg content layer number, number of zinc coated steel having high content of Mg pivotably Al provided Mg a-Si oxide. The, to carry in the embodiment which can be implemented as supporting and [...] sacrificial corrosion resistant properties.

Said alloy coated steel sheet is, although not shown in fig. 5, said steel sheet, and said Al provided Mg a-Si alloy layer positioned between the layer contains hollow beads can Al a-Si alloy.

Said Al a-Si alloy layer, Al hot dip steel plate and may be present, or said manufacturing method Al during a heat treatment in a diffusion surface direction and Si is newly formed can be.

The, Al a-Si alloy layer, and sequential manner prevents corrosion Al provided Mg a-Si alloy layer can be.

Further said alloy coated steel sheet, said steel sheet (21), and said Al provided Mg a-Si alloy layer (23) positioned between the Al a-Si a-Fe alloy layer (22) may be provided further including, as is aforementioned Al morning fair number plated steel sheet, where the metal plating layer to diffuse into the steel sheet is in Fe Al a-Si can be. Or, Mg Fe plating layer to diffuse into the steel sheet during a heat treatment following Al a-Si is in the metal layers of the timbre can be.

The, Al a-Fe a-Si alloy layer, Al a-Si alloy layer, and sequential manner prevents corrosion Al provided Mg a-Si alloy layer can be. As a result physical blocking type, or a single sacrificial corrosion resistant manner such as aluminum or zinc coating for preventing corrosion general excellent corrosion resistance than other characteristics.

In addition, said alloy coated steel sheet is, said Al provided Mg a-Si alloy layer located on the Mg Mg Al provided Mg alloy layer formed along further including diffusion layer or may be disclosed. The, sequential manner corrosion resistance, can be excellent corrosion resistance characteristics.

In addition, said alloy coated steel sheet Al provided Mg a-Si alloy layer, an alloy layer in Al provided Mg alloy phase, including granular Mg a-Si alloy can be formed as.

In addition this type, which contribute to improve corrosion resistance, in particular aforementioned efined building.

Hereinafter of the present invention preferred embodiment and comparison examples described substrate. In the embodiment of the present invention in the embodiment for the present invention is provided in the embodiment is to however is not limited to one and not the.

In the embodiment: alloy coated steel sheet number bath

In the embodiment 1

Weight % Si 9 on cold-rolled steel sheet, Al 88% by weight, and a single sided plating quantity with cup department including Al Fe plating layer 15 g/m² Formed molten aluminum plated steel sheet Royal. Min Al plating layer thickness is about 6 um.

Separating said residual oil on the surface of the steel sheet such as a stand-alone embodiment whether rust dropped from the other alkali for his number.

Then, while supplying said steel sheet steel sheet supply device is evacuated through container, that net magnetron sputtering source is disposed within the vacuum vessel reverse e surface clean his embodiment.

After clean, then through the steel sheet, is disposed within the vacuum vessel 1 Mg Al through electromagnetic source amount on a plating layer. 0um was vacuum coating thickness.

After completing the coating, then continue to move steel sheet discharge port, at least one out his thermal process using a induction heating device. Heat treatment continue to steel alloy coated steel sheet is used for a feeding number produced therewith obtained.

In the embodiment 2

Such as a high pressure liquid coolant method alloying said in the embodiment 1 was coated steel sheet number.

In the embodiment 3

Such as a high pressure liquid coolant method alloying said in the embodiment 1 was coated steel sheet number.

In the embodiment 4

1 Al Mg on a plating layer. 5um [...] vacuum coating thickness and improving a number, such as a high pressure liquid coolant method alloying said in the embodiment 1 was coated steel sheet number.

Comparison example 1

Weight % Si 9 on steel, Al 88% by weight, and a single sided plating quantity with cup department including Al Fe plating layer 15 g/m² Formed molten aluminum plated steel sheet Royal.

Comparison example 2

Single-sided plating amount 40 g/m² Of the work through a zinc plated steel sheet.

Comparison example 3

Single-sided plating amount 137. 5 g/m² Royal molten zinc plated steel sheet.

Said in the embodiment 1 to 4, and comparison example 1 to 3 in table 1 for information about the strengthened prepared by the number shop window.

Experiment example

Experiment example 1: scanning electron microscope (Scanning Electron Microscope, SEM) Photographic observation

Also in the embodiment 2 of Figure 6 shows a scanning electron microscope photograph of solid plate prior to heat treatment of molten aluminum coated Mg after heat treatment are disclosed.

(A) of Figure 6 Mg coating on ceramic joint body is not a homepage on scanning electron microscope embodiment heat treating of steel plate, cold rolled steel sheet (51), Al a-Fe a-Si alloy layer (52), Al a-Si alloy layer (53) and Mg coating layer (54) can be considering.

(B) heat treatment embodiment of Figure 6 is a scanning electron microscope of a homepage in the embodiment 2, Mg Al a-Si alloy layer is a direction Al provided Mg a-Si alloy layer (55) formed can be confirmed.

In Figure 7 said in the embodiment 4 scanning electron microscope photograph of coated steel alloy prepared by the number are disclosed. Coating layer content of each component in respective line (line) have been designated. In Figure 7 you will, Al provided Mg-a Si alloy layer surface remains high content of predetermined depth Mg multivalent, after making sure that the interface between the steel sheet direction can be reduced. In addition, plating can be also present identifying Al a-Si.

Experiment example 2: transmission electron microscope (Transmission Electron Microscope, TEM) Photographic observation

In TEM for coated steel alloy prepared by the number Figure 8 in the embodiment 2 photograph disclosed. In Figure 8, Al provided Mg a-Si alloy layer, Al₃ Mg₂ In alloy layer including phase, Mg₂ The presence of Si alloy granular form can be confirmed.

Experiment example 3: XRD analysis

For coated steel alloy prepared by the number in said in the embodiment 1 in the embodiment 2 and X-a Ray diffraction device (device name: D/MAX provided 2500V-a PC, number irradiation: Rigaku) conducting using XRD analysis.

Figure 9 in the embodiment 1 of X-a Ray diffraction analysis results for alloy coated steel sheet Al provided Mg a-Si alloy layer are disclosed. 9 studied also appearing, Al Al provided Mg a-Si alloy layer₃ Mg₂ Alloy phase Mg₂ SiFor the production of alloy phase can be known.

Figure 10 in the embodiment 2 of X-a Ray diffraction analysis results for alloy coated steel sheet Al provided Mg a-Si alloy layer are disclosed. 10 studied also appearing, Al Al provided Mg a-Si alloy layer₃ Mg₂ Alloy phase Mg₂ SiFor the production of alloy phase can be known. In addition, pure Al phase Si phase is Al a-Si alloy layer present pure metals is detected to determine the other.

Experiment example 4: glow discharge spectroscopy analysis

Said in the embodiment 3 for coated steel alloy prepared by the number in glow discharge spectroscopy (device name: GDS 850A, number irradiation: NECO) coating layer was formed on a steel sheet using the component.

Also shown to result 11. 11 studied also appearing, molten aluminum plating a preform Mg diffusion can be confirmed. In addition, the high content of Mg Al provided Mg a-Si alloy layer surface, making sure that the interface between the steel sheet can be reduced linearly direction. In addition, content of at least 15% by weight Mg Al provided Mg a-Si alloy layer can be confirmed.

In glow discharge spectroscopy analysis results for coated steel alloy prepared by the number Figure 12 said in the embodiment 4 are disclosed. Studied at 12 also appearing, molten aluminum plating a preform Mg diffusion can be confirmed. In addition, switches the predetermined depth surface increased unsaturated fatty acid content of Mg Al provided Mg a-Si alloy layer, the interface between a direction after making sure that the steel can be reduced. In addition, content of at least 15% by weight Mg Al provided Mg a-Si alloy layer can be confirmed.

Experiment example 5: corrosion resistance evaluation

Said in the embodiment 1 to 4, and comparison example 1 to 3 for a salt water spraying test (ASTM B-a 117) using method of steel sheet sample initial enemy [cheng occurrence time reference surface corrosion resistance was assessed. For table 2 have shown to result.

Studied at said known at table 2, comparison example 1 to 3 is also a power [...] 100 time ago. While, in the embodiment 1 to 4 is minimal when compared with 10 times in comparison example, making sure that the capable of about 90 times has corrosion resistance.

, the alloy of the present invention Al provided Mg a-Si layer having coated steel sheet, compared to coated steel alloy of the existing method has a very improved corrosion, corrosion-resistant characteristic required of the first and second article to the surface treatment of number may be hif2e..

The present invention refers to said in the embodiment are different but limited to number tank can be in various forms, in the present invention is technical idea of the present invention is provided to essential features or person with skill in the art without changing other specific embodiment can form can be understand are disclosed. In the embodiment described above the exemplary non-limiting all sides are understood to which must substrate.