Preparation method of fingerprint-resistant zinc-aluminum-magnesium steel sheet and fingerprint-resistant zinc-aluminum-magnesium steel sheet

Abstract

The present application relates to a method for preparing a hot-base zinc-aluminum-magnesium fingerprint-resistant steel plate, which comprises the following steps: providing a steel plate; hot-dip-plating the steel plate with a zinc-aluminum-magnesium alloy liquid to obtain a steel plate with a zinc-aluminum-magnesium alloy liquid; air-knife purging, cooling, and water-quenching the steel plate with the zinc-aluminum-magnesium alloy melt to obtain a zinc-aluminum-magnesium coated steel plate; performing a light finishing treatment and a straightening treatment on the zinc-aluminum-magnesium coated steel plate to obtain a flat zinc-aluminum-magnesium coated steel plate; roller-coating the flat zinc-aluminum-magnesium coated steel plate with a passivation liquid to form a passivation film to obtain a fingerprint-resistant zinc-aluminum-magnesium steel plate, wherein the zinc-aluminum-magnesium alloy melt comprises the following components: Mg: 2.1%-3.1%, Al: 5.5%-7%, Si: 0.05%-0.12%, Fe: 0.005-0.01%, and the remainder is Zn. The embodiment of the present application adjusts the composition of the zinc-aluminum-magnesium alloy melt and then passivates the zinc-aluminum-magnesium coated steel plate with a specific passivation solution, so that the surface of the fingerprint-resistant zinc-aluminum-magnesium steel plate is not easily contaminated by dirt and has the characteristic of fingerprint resistance.

Description

Technical Field

[0001] The present application relates to the field of steel products, and in particular to a steel plate with a zinc-aluminum-magnesium coating. Background Art

[0002] Zinc-aluminum-magnesium steel plate refers to a steel plate with a zinc-aluminum-magnesium coating. Steel plates with high corrosion resistance are often required in fields such as steel silos, hardware machinery, etc. The traditional technology is to galvanize the steel plate, which is called ultra-thick zinc-layer pure zinc steel plate. The ultra-thick zinc-layer pure zinc steel plate with a pure zinc layer thickness of 800g / m2 can have a service life of up to 30 years. However, the coating of ultra-thick zinc-layer pure zinc steel plates is usually prepared by hot dip plating, but the coating is too thick, which makes production difficult and costly. For zinc-aluminum-magnesium steel plates, the service life of a coating thickness of 275g / m2 can reach more than 30 years. The reduced coating thickness makes production less difficult, and the cost is lower than that of ultra-thick zinc-layer pure zinc steel plates.

[0003] However, zinc-aluminum-magnesium steel is a relatively new product and there are still some problems to be solved. The most prominent problem at present is the surface fingerprint resistance. After the human hand touches the surface of zinc-aluminum-magnesium steel, the surface of zinc-aluminum-magnesium steel will leave obvious marks, affecting the appearance. Summary of the invention

[0004] The embodiments of the present application provide a method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate and a fingerprint-resistant zinc-aluminum-magnesium steel plate to solve the technical problem of poor fingerprint resistance of the zinc-aluminum-magnesium steel plate.

[0005] In a first aspect, an embodiment of the present application provides a method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate, and the method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate comprises the following steps:

[0006] Provide steel plates;

[0007] Hot-dip coating the steel plate with zinc-aluminum-magnesium alloy liquid to obtain a steel plate coated with zinc-aluminum-magnesium alloy liquid;

[0008] The steel plate with zinc-aluminum-magnesium alloy melt is subjected to air knife blowing, cooling and water quenching to obtain a zinc-aluminum-magnesium coated steel plate;

[0009] The zinc-aluminum-magnesium coated steel plate is subjected to skin finishing treatment and straightening treatment to obtain a flat zinc-aluminum-magnesium coated steel plate;

[0010] The flat zinc-aluminum-magnesium coated steel sheet is subjected to roller coating treatment with a passivation solution to form a passivation film to obtain the fingerprint-resistant zinc-aluminum-magnesium steel sheet.

[0011] Wherein, the zinc-aluminum-magnesium alloy melt includes the following components in terms of mass percentage: Mg: 2.1%-3.1%, Al:

[0012] 5.5%-7%, Si: 0.05%-0.12%, Fe: 0.005-0.01%, the balance is Zn, the balance is Zn.

[0013] In some embodiments of the present application, in the roller coating process, the roller coating pressure is 1000-2000N, and the roller coating speed ratio is 0.9-1.5.

[0014] In some embodiments of the present application, the thickness of the passivation film is 0.9-1.8 g / m 2 .

[0015] In some embodiments of the present application, the forming of the passivation film comprises the following steps:

[0016] The zinc-aluminum-magnesium coated steel plate coated with the passivation solution is dried in a far-infrared electric heating reactor.

[0017] In some embodiments of the present application, the temperature of the fingerprint-resistant zinc-aluminum-magnesium steel plate is controlled to be 100-160°C when the drying is completed.

[0018] In some embodiments of the present application, the method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel plate further comprises the following steps:

[0019] The obtained anti-fingerprint zinc-aluminum-magnesium steel plate is cooled simultaneously by air-cooling spray and water-cooling roller.

[0020] In some embodiments of the present application, the surface roughness of the zinc-aluminum-magnesium coated steel sheet is adjusted to 0.6-1.8 μm and the RPc is adjusted to 80-120 by the skin finishing treatment.

[0021] In some embodiments of the present application, the straightening treatment adopts a two-bending and two-straightening process, wherein the insertion amount of the straightening roller is 15-26 mm.

[0022] In a second aspect, an embodiment of the present application provides a fingerprint-resistant zinc-aluminum-magnesium steel plate, which is prepared by the method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel plate described in any embodiment of the first aspect.

[0023] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0024] The embodiment of the present application adjusts the composition of the zinc-aluminum-magnesium alloy melt and then passivates the zinc-aluminum-magnesium coated steel plate with a specific passivation solution, so that the surface of the fingerprint-resistant zinc-aluminum-magnesium steel plate is not easily contaminated by dirt and has the characteristic of fingerprint resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0026] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0027] Figure 1 A schematic flow chart of a method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate provided in an embodiment of the present application;

[0028] Figure 2 This is a schematic diagram of the surface of the thermal-based zinc-aluminum-magnesium fingerprint-resistant steel plate of Example 1, which has good fingerprint-free surface;

[0029] Figure 3 Schematic diagram of the surface of the comparative example of the hot-based zinc-aluminum-magnesium fingerprint-resistant steel plate with poor fingerprints. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0031] Unless otherwise specified, the terms used herein should be understood as commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. In the event of a conflict, this specification takes precedence.

[0032] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0033] The existing zinc-aluminum-magnesium steel plate has the technical problem of poor surface fingerprint resistance.

[0034] The technical solution provided by the embodiments of the present application is to solve the above technical problems, and the overall idea is as follows:

[0035] In a first aspect, an embodiment of the present application provides a method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate, and the method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate comprises the following steps:

[0036] S1: Provide steel plate;

[0037] S2: hot-dip coating the steel plate with zinc-aluminum-magnesium alloy liquid to obtain a steel plate with zinc-aluminum-magnesium alloy liquid;

[0038] S3: performing air knife blowing, cooling, and water quenching on the steel plate with the zinc-aluminum-magnesium alloy melt to obtain a zinc-aluminum-magnesium coated steel plate;

[0039] S4: performing skin finishing and straightening treatment on the zinc-aluminum-magnesium coated steel plate to obtain a flat zinc-aluminum-magnesium coated steel plate;

[0040] S5: roller coating the flat zinc-aluminum-magnesium coated steel sheet with a passivation solution to form a passivation film to obtain the fingerprint-resistant zinc-aluminum-magnesium steel sheet.

[0041] Wherein, the zinc-aluminum-magnesium alloy melt includes the following components in terms of mass percentage: Mg: 2.1%-3.1%, Al:

[0042] 5.5%-7%, Si: 0.05%-0.12%, Fe: 0.005-0.01%, and the balance is Zn.

[0043] Those skilled in the art can understand that the provision of the steel plate in step S1 refers to providing a steel plate suitable for hot dip coating, generally a strip steel. As an example, the present application also provides a method for processing molten steel into a steel plate suitable for hot dip coating, comprising the following steps:

[0044] S11: Casting molten steel into slabs;

[0045] S12: hot rolling and continuous pickling of the slab;

[0046] S13: placing the pickled slab into a NOF furnace for heating;

[0047] S14: High-hydrogen cooling is performed on the heated slab.

[0048] The above steps S11-S14 are only used as an example for implementing the present application. Those skilled in the art may select other methods to obtain a steel plate suitable for hot-dip coating based on conventional technical knowledge in the field.

[0049] Those skilled in the art can understand that air knife blowing refers to blowing the surface of the steel plate with zinc-aluminum-magnesium alloy liquid by spraying high-speed airflow with an air knife, and its technical purpose is to make the zinc-aluminum-magnesium alloy liquid evenly distributed on the surface of the steel plate. The air knife is a conventional device in the field.

[0050] Those skilled in the art will appreciate that cooling may be performed in a cooling tower, the technical purpose of which is to cool the steel plate containing the zinc-aluminum-magnesium alloy liquid to a temperature suitable for water quenching.

[0051] Those skilled in the art will understand that water quenching refers to further cooling of the strip after it enters the cooling water tank to ensure that the temperature of the strip meets the process requirements before it enters the flattening process. The technical purpose is to further reduce the surface temperature of the strip.

[0052] Those skilled in the art can understand that finishing treatment refers to finishing processing on the surface of zinc-aluminum-magnesium coated steel plate, and its technical purpose is to adjust the surface roughness. Finishing processing includes but is not limited to super polishing, polishing, rolling, etc.

[0053] The present application adjusts the composition of the zinc-aluminum-magnesium alloy melt and then passivates the zinc-aluminum-magnesium coated steel plate with a specific passivation solution, so that the surface of the fingerprint-resistant zinc-aluminum-magnesium steel plate is not easily contaminated by dirt and has the characteristic of fingerprint resistance.

[0054] In some embodiments of the present application, in the roller coating process, the roller coating pressure is 1000-2000N.

[0055] Those skilled in the art will appreciate that a beneficial effect of a roller coating pressure of 1000-2000N is that the thickness of the passivation film on the surface of the steel strip after roller coating is uniform.

[0056] In some embodiments of the present application, the thickness of the passivation film is 0.9-1.8 g / m 2 .

[0057] Those skilled in the art will appreciate that the thickness of the passivation film is 0.9-1.8 g / m 2 The beneficial effect is that it has good anti-fingerprint performance.

[0058] In some embodiments of the present application, the forming of the passivation film comprises the following steps:

[0059] S51: Drying the zinc-aluminum-magnesium coated steel plate coated with the passivation solution in a far-infrared electric heating reactor.

[0060] Those skilled in the art will appreciate that the beneficial effect of drying the passivation solution by using a far-infrared electric heating reactor is to increase the thickness and compactness of the passivation surface film of the steel plate.

[0061] In some embodiments of the present application, the temperature of the fingerprint-resistant zinc-aluminum-magnesium steel plate is controlled to be 100-160°C when the drying is completed.

[0062] Those skilled in the art will appreciate that the beneficial effect of controlling the temperature at 100-160° C. upon completion of drying is to increase the thickness and density of the passivation surface film on the steel plate and remove surface moisture.

[0063] In some embodiments of the present application, the method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel plate further comprises the following steps:

[0064] S6: The obtained anti-fingerprint zinc-aluminum-magnesium steel plate is cooled simultaneously by air-cooling spray and water-cooling roller.

[0065] Those skilled in the art will appreciate that the beneficial effect of using both air-cooling spray and water-cooling rollers for cooling is to reduce the surface temperature of the steel strip.

[0066] In some embodiments of the present application, the surface roughness of the zinc-aluminum-magnesium coated steel sheet is adjusted to 0.6-1.8 μm and the RPc is adjusted to 80-120 by the skin finishing treatment.

[0067] Those skilled in the art will understand that RPc refers to the peak value of surface roughness.

[0068] Those skilled in the art will appreciate that the beneficial effect of adjusting the surface roughness and RPc to the above parameters is to improve the uniformity of the film thickness of the passivation coating.

[0069] In some embodiments of the present application, the straightening treatment adopts a two-bending and two-straightening process, wherein the insertion amount of the straightening roller is 15-26 mm.

[0070] Those skilled in the art can understand that the two-bend two-straightening process is a conventional process in the art, and the two-bend two-straightening process is implemented by a two-bend two-straightening continuous stretch bending straightening machine. The two-bend two-straightening continuous stretch bending straightening machine has two stretching and straightening rollers, and the insertion amount of the stretching and straightening rollers refers to the distance between the two stretching and straightening rollers.

[0071] In the second aspect, based on a general inventive concept, the embodiment of the present application provides a fingerprint-resistant zinc-aluminum-magnesium steel plate, which is prepared by the method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate described in any embodiment of the first aspect. The specific implementation of the fingerprint-resistant zinc-aluminum-magnesium steel plate can refer to the embodiment of the first aspect. Since the fingerprint-resistant zinc-aluminum-magnesium steel plate adopts part or all of the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here one by one.

[0072] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0073] Example 1

[0074] This embodiment provides a method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate, comprising the following steps:

[0075] Sa: Provide steel plate;

[0076] Sb: hot-dip coating the steel sheet with zinc-aluminum-magnesium alloy liquid to obtain a steel sheet with zinc-aluminum-magnesium alloy liquid;

[0077] Sc: performing air knife blowing, cooling, and water quenching on the steel plate with the zinc-aluminum-magnesium alloy melt to obtain a zinc-aluminum-magnesium coated steel plate;

[0078] Sd: performing skin finishing and straightening treatment on the zinc-aluminum-magnesium coated steel sheet to obtain a flat zinc-aluminum-magnesium coated steel sheet;

[0079] Se: After the flat zinc-aluminum-magnesium coated steel sheet is roller-coated with a passivation solution, the zinc-aluminum-magnesium coated steel sheet coated with the passivation solution is dried in a far-infrared electric heating reactor to form a passivation film to obtain the anti-fingerprint zinc-aluminum-magnesium steel sheet;

[0080] Sf: The anti-fingerprint zinc-aluminum-magnesium steel plate is cooled simultaneously by air-cooling spray and water-cooling roller.

[0081] Wherein, the zinc-aluminum-magnesium alloy melt includes the following components in mass percentage: Mg: 2.6%, Al: 6.6%, Si: 0.08%, Fe: 0.008%, and the balance is Zn;

[0082] The skin-finishing process is implemented by rolling, the working roll is a rough roll, the roll diameter is 620mm, and the rolling force is 3500kN. After skin-finishing, the surface roughness of the strip is 1.0μm, and the RPC of the strip surface is 95;

[0083] The straightening treatment adopts a two-bend two-straightening process, in which the straightening roller insertion amounts are 15 / 15 / 23 / 23mm respectively;

[0084] Roller coating process adopts horizontal roller coating process, roller pressure is 1500N, and the thickness of fingerprint-resistant passivation film is controlled at 1.1g / m 2 ;

[0085] When the drying is completed, the temperature of the fingerprint-resistant zinc-aluminum-magnesium steel plate is controlled to be 112°C.

[0086] Please refer to Figure 2 , Figure 2 The surface state of the hot-base zinc-aluminum-magnesium anti-fingerprint steel plate of this embodiment after being pressed by a palm is shown. It can be seen that the hot-base zinc-aluminum-magnesium anti-fingerprint steel plate of this embodiment has no trace at all after being pressed by a palm, and has good anti-fingerprint performance.

[0087] Example 2

[0088] The difference between this embodiment and embodiment 1 is only that:

[0089] The zinc-aluminum-magnesium alloy melt comprises the following components in percentage by mass: Mg: 2.5%, Al: 6.5%, Si: 0.08%, Fe: 0.008%, and the balance is Zn;

[0090] The skin-finishing process is implemented by rolling, the working roll is a rough roll, and the rolling force is 3500kN. After skin-finishing, the surface roughness of the strip is 1.0μm, and the RPC of the strip surface is 95;

[0091] The straightening treatment adopts a two-bend two-straightening process, in which the straightening roller insertion amounts are 15 / 15 / 23 / 23mm respectively;

[0092] Roller coating process adopts horizontal roller coating process, roller pressure is 1500N, and the thickness of fingerprint-resistant passivation film is controlled at 1.1g / m 2 ;

[0093] When the drying is completed, the temperature of the fingerprint-resistant zinc-aluminum-magnesium steel plate is controlled to 112°C.

[0094] Example 3

[0095] The difference between this embodiment and embodiment 1 is only that:

[0096] The zinc-aluminum-magnesium alloy melt comprises the following components in percentage by mass: Mg: 2.3%, Al: 6.6%, Si: 0.08%, Fe: 0.008%, and the balance is Zn;

[0097] The skin-finishing process is implemented by rolling, the working roll is a rough roll, and the rolling force is 3500kN. After skin-finishing, the surface roughness of the strip is 1.0μm, and the RPC of the strip surface is 95;

[0098] The straightening treatment adopts a two-bend two-straightening process, in which the straightening roller insertion amounts are 15 / 15 / 23 / 23mm respectively;

[0099] Roller coating process adopts horizontal roller coating process, roller pressure is 1600N, and the thickness of anti-fingerprint passivation film is controlled at 1.1g / m 2 ;

[0100] When the drying is completed, the temperature of the fingerprint-resistant zinc-aluminum-magnesium steel plate is controlled to 110°C.

[0101] Example 4

[0102] The difference between this embodiment and embodiment 1 is only that:

[0103] The zinc-aluminum-magnesium alloy melt comprises the following components in percentage by mass: Mg: 2.4%, Al: 6.7%, Si: 0.09%, Fe: 0.009%, and the balance is Zn;

[0104] The skin-finishing process is implemented by rolling, the working roll is a rough roll, and the rolling force is 3500kN. After skin-finishing, the surface roughness of the strip is 1.0μm, and the RPC of the strip surface is 90;

[0105] The straightening treatment adopts a two-bend two-straightening process, in which the straightening roller insertion amounts are 15 / 15 / 23 / 23mm respectively;

[0106] Roller coating process adopts horizontal roller coating process, roller pressure is 1900N, and the thickness of anti-fingerprint passivation film is controlled at 1.1g / m 2 ;

[0107] When the drying is completed, the temperature of the fingerprint-resistant zinc-aluminum-magnesium steel plate is controlled to be 110°C.

[0108] Example 5

[0109] The difference between this embodiment and embodiment 1 is only that:

[0110] The zinc-aluminum-magnesium alloy melt comprises the following components in percentage by mass: Mg: 2.5%, Al: 6.8%, Si: 0.09%, Fe: 0.009%, and the balance is Zn;

[0111] The skin-finishing process is implemented by rolling, the working roll is a rough roll, and the rolling force is 3500kN. After skin-finishing, the surface roughness of the strip is 1.0μm, and the RPC of the strip surface is 95;

[0112] The straightening treatment adopts a two-bend two-straightening process, in which the straightening roller insertion amounts are 15 / 15 / 23 / 23mm respectively;

[0113] Roller coating process adopts horizontal roller coating process, roller pressure is 1800N, and the thickness of anti-fingerprint passivation film is controlled at 1.0g / m 2 ;

[0114] When the drying is completed, the temperature of the fingerprint-resistant zinc-aluminum-magnesium steel plate is controlled to be 113°C.

[0115] Comparative Example

[0116] The difference between this comparative example and Example 1 is only that:

[0117] The zinc-aluminum-magnesium alloy melt includes the following components: Mg: 1.5%, Al: 4.5%, Si: 0.085%, Fe: 0.008%, and the balance is Zn.

[0118] The surface quality of the hot-base zinc-aluminum-magnesium anti-fingerprint steel plate obtained in this comparative example is poor. The passivation film thickness uniformity of the part with poor surface quality after passivation coating is poor, and the film thickness is 0.5-0.9g / m2. Please refer to Figure 3 , Figure 3The surface state of the hot-base zinc-aluminum-magnesium fingerprint-resistant steel plate of this comparative example after being pressed with a palm is shown. After the steel plate is pressed with a finger, obvious fingerprints appear on the surface of the strip steel, which cannot be eliminated.

[0119] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0120] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the description of the present application specification, the terms "including", "comprising", etc. refer to "including but not limited to". Moreover, the terms "including", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements defined by the sentence "including..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. In this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. For the association relationship of more than three associated objects described by "and / or", it means that any one of these three associated objects can exist alone, or any at least two of them exist at the same time. For example, for A, and / or B, and / or C, it can be represented that any one of A, B, and C exists alone, or any two of them exist at the same time, or three of them exist at the same time. In this article, "at least one" refers to one or more, and "multiple" refers to two or more. "At least one", "the following at least one (individual)" or similar expressions refer to any combination of these items, including any combination of single (individual) or plural (individual). For example, "at least one (individual) of a, b, or c", or "at least one (individual) of a, b, and c", can all represent: a, b, c, ab (i.e. a and b), ac, bc, or abc, wherein a, b, and c can be single or multiple, respectively.

[0121] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A method for preparing a fingerprint-resistant zinc-aluminum-magnesium steel plate, characterized in that: The method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel plate comprises the following steps: Provide steel plates; Hot-dip coating the steel plate with zinc-aluminum-magnesium alloy liquid to obtain a steel plate coated with zinc-aluminum-magnesium alloy liquid; The steel plate with the zinc-aluminum-magnesium alloy melt is subjected to air knife blowing, cooling, and water quenching to obtain a zinc-aluminum-magnesium coated steel plate; The zinc-aluminum-magnesium coated steel plate is subjected to skin finishing treatment and straightening treatment to obtain a flat zinc-aluminum-magnesium coated steel plate; The flat zinc-aluminum-magnesium coated steel sheet is subjected to roller coating treatment with a passivation solution to form a passivation film to obtain the fingerprint-resistant zinc-aluminum-magnesium steel sheet. Wherein, the zinc-aluminum-magnesium alloy melt includes the following components in mass percentage: Mg: 2.1%-3.1%, Al: 5.5%-7%, Si: 0.05%-0.12%, Fe: 0.005-0.01%, and the balance is Zn; In the roller coating process, the roller coating pressure is 1000-2000N, and the roller coating speed ratio is 0.9-1.5; The thickness of the passivation film is 0.9-1.8 g / m 2 ; The skin finishing treatment adjusts the surface roughness of the zinc-aluminum-magnesium coated steel sheet to 0.6-1.8 μm and the RPc to 80-120.

2. The method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel sheet according to claim 1, characterized in that: The forming of the passivation film comprises the following steps: The zinc-aluminum-magnesium coated steel plate coated with the passivation solution is dried in a far-infrared electric heating reactor.

3. The method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel sheet according to claim 2, characterized in that: When the drying is completed, the temperature of the fingerprint-resistant zinc-aluminum-magnesium steel plate is controlled to be 100-160°C.

4. The method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel sheet according to claim 1, characterized in that: The method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel plate further comprises the following steps: The obtained anti-fingerprint zinc-aluminum-magnesium steel plate is cooled simultaneously by air-cooling spray and water-cooling roller.

5. The method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel sheet according to claim 1, characterized in that: The straightening treatment adopts a two-bending and two-straightening process, wherein the insertion amount of the straightening roller is 15-26 mm.

6. A fingerprint-resistant zinc-aluminum-magnesium steel plate, characterized in that: The fingerprint-resistant zinc-aluminum-magnesium steel sheet is prepared by the method for preparing the fingerprint-resistant zinc-aluminum-magnesium steel sheet according to any one of claims 1 to 5.

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