TW202405201A - Zn-al-mg-based coated checkered sheet - Google Patents

Abstract

A Zn-Al-Mg-based coated checkered steel sheet has a convex part and a flat part on a sheet surface. A plating layer of the steel sheet has a predetermined chemical composition. At a center part of the convex part in its longitudinal direction, a cutting surface that is perpendicular to the longitudinal direction of the convex part and obtained by cutting along a thickness direction of the sheet is observed. A thickness ratio of the plating layer on the flat part on the left and right sides of the convex part (thickness of the plating layer on the left side/thickness of the plating layer on the right side) is 0.2 or more and 5.0 or less. A checker height T-t and a gap height x satisfy the following formulas 1 and 2. The checker height T-t is a checker height where a thickness of a substrate checkered steel sheet at the convex part is T and a thickness of the substrate checkered steel sheet at the flat part is t. The gap height x is a gap height between a plated checkered steel sheet and a resting surface when it is resting. Formula 1 is x/(T-t)≤1.5. Formula 2 is 0.5&ltT-t≤t.

Description

Zn-Al-Mg based plated reticulated steel plate

The present disclosure relates to a Zn-Al-Mg based plated corrugated steel plate.

Corrugated steel plate is a steel plate with continuous anti-slip convex portions (that is, protrusions) added to the surface by rolling. Generally speaking, convex portions with fixed width, fixed length and fixed height are provided at fixed angles and fixed intervals in the rolling direction. Corrugated steel plates are usually produced by hot rolling. Furthermore, corrugated steel plates are used in floors or steps of large vehicles (buses, trucks, etc.), paving in three-dimensional parking lots, paving in factories, ship decks, temporary scaffolding or ladders at construction sites, etc.

For example, Patent Document 1 discloses: "A hot-dip galvanized corrugated steel plate, which has a base steel plate, a Ni plating layer disposed on the surface of the base steel plate, and a hot plating layer disposed on the surface of the Ni plating layer, and The plate surface has a convex part and a flat part; and the film thickness of the Ni plating layer before the convex part is 0.07~0.4 μm per side, and the film thickness of the Ni plating layer before the flat part is 0.05~0.35 per side. μm, the film thickness of the Ni plating layer on the convex part is greater than 100% and 400% or less relative to the film thickness of the Ni plating layer on the flat part, and the adhesion amount of the molten plating layer is 60 per side ~400g/m ² , and the chemical composition of the aforementioned molten plating layer includes in mass %: Al: greater than 1.0% and less than 26%, Mg: 0.05~10%, Si: 0~1.0%, Sn: 0~3.0 % and Ca: 0~1.0%, and the remainder is composed of Zn and impurities."

Furthermore, Patent Document 2 discloses: "A method for continuous molten metal plating of a strip-shaped corrugated steel plate. After pickling the strip-shaped corrugated steel plate, the molten metal plating is continuously performed under conditions that satisfy the following requirements: Annealing temperature: 450~850℃, steel strip tension in the annealing furnace: 0.3~2.0kg/mm ² , steel strip tension in the plating production line: 0.3~3.0kg/mm ² , gas pressure for wiping molten metal: 0.02~1.5kg/cm ^2. ". Prior art documents Patent documents

Patent document 1: International Gazette No. 2019/054483 Patent Document 2: Japanese Patent No. 2743774

The problem to be solved by the invention Corrugated steel plates are mostly used outdoors, so corrosion resistance is required. Therefore, as disclosed in Patent Documents 1 to 2, hot-dip plating is performed on the corrugated steel plate to improve the corrosion resistance.

On the other hand, the textured steel plate will be used for scaffolding, anti-skid, etc., so it also requires flatness. However, the corrugated steel plate is a steel plate that has local plate thickness differences through convex portions and flat portions. Therefore, if the corrugated steel plate is hot-plated in order to improve the corrosion resistance, the amount of expansion and shrinkage caused by the temperature change will be different between the convex portion and the flat portion of the corrugated steel plate, and the corrugated steel plate will Deformation. If the deformed plated mesh steel plate is made into products, the flatness will become worse. In addition, once the flatness deteriorates, the thickness of the plating layer will vary, and the corrosion resistance and processability will decrease. In particular, compared with Zn-based plating baths, the viscosity of Zn-Al-Mg alloy-based plating baths is lower. Therefore, if the flatness of the reticulated steel plate becomes worse, the thickness of the plating layer will easily become uneven, and the corrosion resistance will be affected. and processability will be reduced. Therefore, it is required to further improve the flatness of Zn-Al-Mg based plated textured steel sheets.

Therefore, the subject of this disclosure is to provide a Zn-Al-Mg based plated textured steel plate excellent in flatness, corrosion resistance and workability.

means to solve problems The above problems can be solved in the following ways. <1> A Zn-Al-Mg plated textured steel plate, which has a base textured steel plate and a plating layer. The base textured steel plate is provided with a convex part and a flat part on one of the plate surfaces, and the plating layer It is arranged on the plate surface provided with convex portions and flat portions of the aforementioned base corrugated steel plate, and the plating layer includes a Zn-Al-Mg alloy layer; The aforementioned plating layer has a chemical composition consisting of: In mass %, Zn: greater than 65.0%, Al: greater than 1.0% and less than 25.0%, Mg: greater than 1.0% and less than 12.5%, Sn: 0%~5.0%, Bi: 0%~less than 5.0%, In: 0%~less than 2.0%, Ca: 0%~3.00%, Y: 0%~0.5%, La: 0%~less than 0.5%, Ce: 0%~less than 0.5%, Si: 0%~less than 2.5%, Cr: 0%~less than 0.25%, Ti: 0%~less than 0.25%, Zr: 0%~less than 0.25%, Mo: 0%~less than 0.25%, W: 0%~less than 0.25%, Ag: 0%~less than 0.25%, P: 0%~less than 0.25%, Ni: 0%~less than 0.25%, Co: 0%~less than 0.25%, V: 0%~less than 0.25%, Nb: 0%~less than 0.25%, Cu: 0%~less than 0.25%, Mn: 0%~less than 0.25%, Li: 0%~less than 0.25%, Na: 0%~less than 0.25%, K: 0%~less than 0.25%, Fe: 0%~5.0%, Sr: 0%~less than 0.5%, Sb: 0%~less than 0.5%, Pb: 0%~less than 0.5%, B: 0%~less than 0.5% and impurities; At the center of the longitudinal direction of the convex part, observe the cut surface obtained by cutting along the plate thickness direction and perpendicular to the longitudinal direction of the convex part. At this time, the plated layer of the flat part on the left and right of the convex part The layer thickness ratio (layer thickness of the left plating layer/layer thickness of the right plating layer) is 0.2 or more and 5.0 or less; and The texture height T-t and the gap height x satisfy the following formulas 1 and 2; the texture height T-t is: let the thickness of the aforementioned base texture steel plate in the aforementioned convex part be T and let the aforementioned base texture in the aforementioned flat part The height of the texture when the thickness of the steel plate is t; the gap height . Formula 1: x/(T-t)≦1.5 Formula 2: 0.5＜T-t≦t The unit of thickness T, t, and gap height x of the base corrugated steel plate in Formula 1 and Formula 2 is "mm". <2> The Zn-Al-Mg plated mesh steel plate of <1>, wherein the Al concentration is greater than 5.0% and less than 25.0%, and the Mg concentration is greater than 3.0% and less than 12.5%. <3> The Zn-Al-Mg plated corrugated steel plate as in <1> or <2>, wherein the aforementioned coating layer contains Al- between the aforementioned base corrugated steel plate and the aforementioned Zn-Al-Mg alloy layer. Fe alloy layer.

Invention effect According to the present disclosure, it is possible to provide a Zn-Al-Mg-based plated mesh steel plate excellent in flatness, corrosion resistance, and workability.

Form used to implement the invention An example of this disclosure will be described below. In addition, in this disclosure, the "%" symbol for the content of each element in the chemical composition means "mass %". The numerical range expressed by "~" means the range including the values recorded before and after "~" as the lower limit and upper limit. The numerical range when the numerical value written before and after "~" is appended with "greater than" or "less than" means a range that does not include these numerical values as the lower limit or upper limit. The element content of a chemical composition is sometimes labeled as element concentration (such as Zn concentration, Mg concentration, etc.).

The Zn-Al-Mg based plated corrugated steel plate (hereinafter also referred to as "coated corrugated steel plate") disclosed in the present disclosure is a plated corrugated steel plate, which has a base corrugated steel plate and a plating layer. The base corrugated steel plate If one of the plate surfaces is provided with convex portions and flat portions, the plating layer is disposed on the plate surface of the aforementioned base corrugated steel plate that is provided with convex portions and flat portions, and the plating layer contains Zn-Al-Mg alloy layer. Moreover, in the plated mesh steel plate of the present disclosure, the plating layer has a predetermined chemical composition; at the central portion of the longitudinal direction of the aforementioned convex portion, the result obtained by observing is orthogonal to the longitudinal direction of the convex portion and cut along the thickness direction of the plate. On the cut surface, at this time, the thickness ratio of the plating layer (thickness of the plating layer on the left side/thickness of the plating layer on the right side) of the flat portions on the left and right sides of the convex portion is 0.2 or more and 5.0 or less; and the texture height T-t and the gap height The height of the pattern; the gap height Formula 1: x/(T-t)≦1.5 Formula 2: 0.5＜T-t≦t The unit of thickness T, t, and gap height x of the base corrugated steel plate in Formula 1 and Formula 2 is "mm".

The plated corrugated steel plate of the present disclosure is a Zn-Al-Mg based plated corrugated steel plate with excellent flatness, corrosion resistance and processability through the above-mentioned structure. Furthermore, the plated corrugated steel plate of the present disclosure was discovered based on the following knowledge and insights.

The inventors studied how to further improve flatness and suppress variations in the thickness of the plating layer even in Zn-Al-Mg plating that has a lower viscosity than a Zn plating bath. As a result, the following knowledge and insights were obtained.

The deterioration of the flatness of the plated corrugated steel plate will not only affect the heating temperature of the base corrugated steel plate before immersion in the plating bath, but also affect the heating rate and cooling rate. Specifically, if the base corrugated steel plate is hot-plated, the amount of expansion and contraction caused by the rapid temperature change in the convex portions and flat portions with different plate thicknesses due to rapid heating and cooling before immersion in the plating bath. Differences will also occur and thus deformation will occur. The reason for this is that unlike ordinary flat steel plates, differences in heating and cooling rates occur between the convex portions and the flat portions of the base corrugated steel plate during heating and cooling.

Therefore, if the base corrugated steel plate is heated and cooled before the immersion plating bath with a gentle heating rate and cooling rate, differences in the heating rate and cooling rate will not easily occur in the convex portions and flat portions with different plate thicknesses. Thereby, the convex part and the flat part are heated and cooled evenly as much as possible, and deformation can be suppressed. As a result, the flatness of the base textured steel plate will be further improved, the variation in the thickness of the coating layer will also be reduced in Zn-Al-Mg based plating, and the corrosion resistance and processability will be improved.

That is, the inventors found that it is possible to obtain a Zn-Al-Mg-based plated textured steel sheet that satisfies the above-mentioned plated layer thickness ratio of the flat portion, the above-mentioned Formula 1 and the above-mentioned Formula 2.

From the above knowledge and insights, it can be found that the plated textured steel plate of the present disclosure will become a Zn-Al-Mg based plated textured steel plate with excellent flatness, corrosion resistance and processability.

The details of the plated corrugated steel plate of the present disclosure will be described below.

(base textured steel plate) The base corrugated steel plate is the steel plate for plating. One surface of the base corrugated steel plate is provided with a convex part and a flat part. The base corrugated steel plate is usually hot rolled to give the shape of the convex portions. The steel type of the base corrugated steel plate is not particularly limited. Examples of the base corrugated steel plate include steel types corresponding to rolled steel materials for general structures stipulated in JIS G3101:2015. The convex shape of the base textured steel plate is imparted by, for example, transferring the concave shape formed in the actuating roll to the steel plate surface during the finishing stage of hot rolling. In addition, the opposite side plate surface facing the plate surface provided with the convex portion and the flat portion in the plate thickness direction is a surface having the surface properties of a normal steel plate. Specifically, the opposite plate surface opposite to the plate surface provided with the convex portion and the flat portion in the plate thickness direction is rolled, for example, by using a normal rolling roll (that is, having a The plate surface is usually roughened by a rolling roller, and the rolling roller is opposed to an actuating roller that can be provided with convex portions and flat portions.

The base corrugated steel plate can also be a pre-plated pre-plated corrugated steel plate. Pre-plated textured steel sheets are obtained by, for example, electrolytic treatment methods or alternative plating methods. In the electrolytic treatment method, the base corrugated steel plate is immersed in a sulfuric acid bath or a chloride bath containing metal ions of various pre-plating components for electrolysis treatment, thereby obtaining the pre-plated corrugated steel plate. In the substitution plating method, the base textured steel plate is immersed in an aqueous solution containing various pre-plating component metal ions and the pH is adjusted with sulfuric acid, so that the metal is substituted and precipitated to obtain the pre-plated textured steel plate. As a preplated textured steel plate, a Ni preplated textured steel plate can be cited as a representative example.

(plated layer) The plating layer contains a Zn-Al-Mg alloy layer. In addition to the Zn-Al-Mg alloy layer, the plating layer may also include an Al-Fe alloy layer. The Al-Fe alloy layer is arranged between the base corrugated steel plate and the Zn-Al-Mg alloy layer.

That is, the plating layer may have a single-layer structure of a Zn-Al-Mg alloy layer, or may have a laminated structure including a Zn-Al-Mg alloy layer and an Al-Fe alloy layer. In the case of a laminated structure, it is preferable that the Zn-Al-Mg alloy layer constitutes the surface of the plating layer. However, an oxide film of approximately 50 nm of elements constituting the plating layer is formed on the surface of the plating layer. However, the thickness of this oxide film is relatively thin relative to the thickness of the entire plating layer, and it is considered that it does not constitute the main body of the plating layer.

The adhesion amount of the plating layer should be 60~500g/m ² per side. If the adhesion amount of the plating layer is 60g/m ² or more, corrosion resistance can be ensured more reliably. On the other hand, if the adhesion amount of the plating layer is 500 g/m ² or less, appearance defects such as sagging of the plating layer can be suppressed.

Next, the chemical composition of the plating layer will be described. The chemical composition of the plating layer is set to a chemical composition consisting of: In mass %, Zn: greater than 65.0%, Al: greater than 1.0% and less than 25.0%, Mg: greater than 1.0% and less than 12.5%, Sn: 0%~5.0%, Bi: 0%~less than 5.0%, In: 0%~less than 2.0%, Ca: 0%~3.00%, Y: 0%~0.5%, La: 0%~less than 0.5%, Ce: 0%~less than 0.5%, Si: 0%~less than 2.5%, Cr: 0%~less than 0.25%, Ti: 0%~less than 0.25%, Zr: 0%~less than 0.25%, Mo: 0%~less than 0.25%, W: 0%~less than 0.25%, Ag: 0%~less than 0.25%, P: 0%~less than 0.25%, Ni: 0%~less than 0.25%, Co: 0%~less than 0.25%, V: 0%~less than 0.25%, Nb: 0%~less than 0.25%, Cu: 0%~less than 0.25%, Mn: 0%~less than 0.25%, Li: 0%~less than 0.25%, Na: 0%~less than 0.25%, K: 0%~less than 0.25%, Fe: 0%~5.0%, Sr: 0%~less than 0.5%, Sb: 0%~less than 0.5%, Pb: 0%~less than 0.5%, B: 0%~less than 0.5% and Impurities.

In the chemical composition of the plating layer, Sn, Bi, In, Ca, Y, La, Ce, Si, Cr, Ti, Zr, Mo, W, Ag, P, Ni, Co, V, Nb, Cu, Mn, Li, Na, K, Fe, Sr, Sb, Pb and B are optional components. That is, the plating layer does not need to contain these elements. When these optional components are included, the content of each optional element is preferably within the range described below.

Here, the chemical composition of the coating layer is the average chemical composition of the entire coating layer (when the coating layer is a single-layer structure of Zn-Al-Mg alloy layer, it is the average chemical composition of the Zn-Al-Mg alloy layer ; When the plating layer has a laminated structure of an Al-Fe alloy layer and a Zn-Al-Mg alloy layer, it is the average chemical composition of the total of the Al-Fe alloy layer and the Zn-Al-Mg alloy layer).

Generally speaking, for the molten plating method, since the formation reaction of the plating layer is almost completed in the plating bath, the chemical composition of the Zn-Al-Mg alloy layer will be roughly the same as the chemical composition of the plating bath. Moreover, in the hot-dip plating method, the Al-Fe alloy layer is formed and grows immediately after being immersed in the plating bath. Moreover, the Al-Fe alloy layer will probably complete the formation reaction in the plating bath, and its thickness is smaller than that of the Zn-Al-Mg alloy layer. Therefore, as long as no special heat treatment such as heating alloying treatment is performed after plating, the average chemical composition of the entire plating layer is essentially the same as the chemical composition of the Zn-Al-Mg alloy layer, and the Al-Fe alloy layer can be ignored. Element.

Each element of the plating layer is explained below.

Zn: greater than 65.0% Zn is an essential element for obtaining corrosion resistance. When the Zn concentration is considered in terms of atomic composition ratio, since the coating layer is composed of low specific gravity elements such as Al and Mg, the atomic composition ratio must still be dominated by Zn. Therefore, the Zn concentration is set to be greater than 65.0%. The Zn concentration should be above 70%. In addition, the upper limit of the Zn concentration is the concentration of the remaining elements other than Zn and impurities.

Al: greater than 1.0% and less than 25.0% Al is an essential element to form Al crystals and ensure corrosion resistance. Furthermore, Al is also an essential element for improving the adhesion of the plating layer and ensuring workability. Therefore, the lower limit of the Al concentration is set to be greater than 1.0% (preferably greater than 5.0%, preferably more than 10.0%). On the other hand, if the Al concentration is excessively increased, corrosion resistance tends to deteriorate. Therefore, the upper limit of the Al concentration is set to less than 25.0% (preferably less than 23.0%).

Mg: greater than 1.0% and less than 12.5% Mg is an essential element to ensure corrosion resistance. Therefore, the lower limit of the Mg concentration is set to be greater than 1.0% (preferably greater than 3.0%, preferably greater than 5.0%). On the other hand, if the Mg concentration is excessively increased, workability tends to deteriorate. Therefore, the upper limit of the Mg concentration is less than 12.5% (preferably 10.0% or less).

Sn: 0~5.0% Sn is an element that contributes to corrosion resistance. Therefore, the lower limit of Sn concentration should be greater than 0% (preferably above 0.1%, preferably above 0.5%). On the other hand, if the Sn concentration is excessively increased, corrosion resistance tends to deteriorate. Therefore, the upper limit of Sn concentration is set to 5.0% or less (preferably 3.0% or less).

Bi: 0%~less than 5.0% A series of elements that contribute to corrosion resistance. Therefore, the lower limit of Bi concentration should be greater than 0% (preferably more than 0.1%, preferably more than 3.0%). On the other hand, if the Bi concentration is excessively increased, corrosion resistance tends to deteriorate. Therefore, the upper limit of Bi concentration is set to less than 5.0% (preferably less than 4.8%).

In: 0%~less than 2.0% In is an element that contributes to corrosion resistance. Therefore, the lower limit of In concentration should be greater than 0% (preferably above 0.1%, preferably above 1.0%). On the other hand, if the In concentration is excessively increased, corrosion resistance tends to deteriorate. Therefore, the upper limit of In concentration is set to less than 2.0% (preferably less than 1.8%).

Ca: 0%~3.0% Ca is an element that can adjust the amount of Mg elution that is most suitable for imparting corrosion resistance. Therefore, the lower limit of Ca concentration should be greater than 0% (preferably above 0.05%). On the other hand, if the Ca concentration is excessively increased, corrosion resistance and workability tend to deteriorate. Therefore, the upper limit of the Ca concentration is set to 3.0% or less (preferably 1.0% or less).

Y：0%~0.5% Y series elements contribute to corrosion resistance. Therefore, the lower limit of Y concentration should be greater than 0% (preferably above 0.1%). On the other hand, if the Y concentration is excessively increased, the corrosion resistance tends to deteriorate. Therefore, the upper limit of the Y concentration is set to 0.5% or less (preferably 0.3% or less).

La and Ce: 0%~less than 0.5% La and Ce are elements that contribute to corrosion resistance. Therefore, the lower limits of the La concentration and the Ce concentration should each be greater than 0% (preferably 0.1% or more). On the other hand, if the La concentration and the Ce concentration are excessively increased, the corrosion resistance tends to deteriorate. Therefore, the upper limits of the La concentration and the Ce concentration are each set to less than 0.5% (preferably 0.4% or less).

Si: 0%~less than 2.5% Si is an element that inhibits the growth of the Al-Fe alloy layer and helps improve corrosion resistance. Therefore, the Si concentration should be greater than 0% (preferably more than 0.05%, preferably more than 0.1%). Especially when Sn is not included (that is, when the Sn concentration is 0%), from the viewpoint of ensuring corrosion resistance, the Si concentration is preferably 0.1% or more (preferably 0.2% or more). On the other hand, if the Si concentration is excessively increased, corrosion resistance and workability tend to deteriorate. Therefore, the upper limit of Si concentration is set to less than 2.5%. Especially from the viewpoint of corrosion resistance, the Si concentration is preferably 2.4% or less, preferably 1.8% or less, more preferably 1.2% or less.

Cr, Ti, Zr, Mo, W, Ag, P, Ni, Co, V, Nb, Cu, Mn, Li, Na and K: 0%~less than 0.25% Cr, Ti, Zr, Mo, W, Ag, P, Ni, Co, V, Nb, Cu, Mn, Li, Na and K are elements that contribute to corrosion resistance. Therefore, the lower limits of the concentrations of Cr, Ti, Zr, Mo, W, Ag, P, Ni, Co, V, Nb, Cu, Mn, Li, Na and K should each be greater than 0% (preferably more than 0.05% , preferably more than 0.1%). On the other hand, if the concentration of Cr, Ti, Zr, Mo, W, Ag, P, Ni, Co, V, Nb, Cu, Mn, Li, Na and K is excessively increased, corrosion resistance will tend to deteriorate. Therefore, the upper limit values of the concentrations of Cr, Ti, Zr, Mo, W, Ag, P, Ni, Co, V, Nb, Cu, Mn, Li, Na and K are each set to less than 0.25%. The upper limit of the concentration of Cr, Ti, Zr, Mo, W, Ag, P, Ni, Co, V, Nb, Cu, Mn, Li, Na and K is preferably 0.22% or less.

Fe: 0%~5.0% When the plating layer is formed by the melt plating method, the Zn-Al-Mg alloy layer and the Al-Fe alloy layer will contain a fixed Fe concentration. It has been confirmed that the Fe concentration of up to 5.0% in the plating layer (especially the Zn-Al-Mg alloy layer) will not cause adverse effects on performance. Most of the Fe is probably contained in the Al-Fe alloy layer, so if the thickness of the layer is large, the Fe concentration will generally increase.

Sr, Sb, Pb and B: 0%~less than 0.5% Sr, Sb, Pb and B are elements that contribute to corrosion resistance. Therefore, the lower limits of the concentrations of Sr, Sb, Pb and B are each preferably greater than 0% (preferably 0.05% or more, preferably 0.1% or more). On the other hand, if the concentrations of Sr, Sb, Pb and B are excessively increased, corrosion resistance tends to deteriorate. Therefore, the upper limit values of the concentrations of Sr, Sb, Pb and B are each set to less than 0.5%.

Impurities Impurities refer to ingredients contained in raw materials or ingredients mixed during the manufacturing process, rather than ingredients intentionally included. For example, in the plating layer, a trace amount of components other than Fe may be mixed as impurities due to mutual atomic diffusion between the base textured steel plate and the plating bath.

The chemical composition of the plating layer is measured by the following method. First, an acid solution is obtained that removes and dissolves the plating layer using an acid. The acid contains an inhibitor that inhibits corrosion of the underlying corrugated steel plate. Then, the resulting acid solution is measured by ICP analysis, whereby the chemical composition of the plating layer can be obtained (when the plating layer is a single-layer structure of the Zn-Al-Mg alloy layer, it is the Zn-Al-Mg alloy layer. Chemical composition; when the plating layer is a laminated structure of an Al-Fe alloy layer and a Zn-Al-Mg alloy layer, it is the total chemical composition of the Al-Fe alloy layer and the Zn-Al-Mg alloy layer). The type of acid is not particularly limited as long as it is an acid that can dissolve the plating layer. In addition, the chemical composition is measured based on the average chemical composition. In addition, in ICP analysis, the Zn concentration is calculated using "Formula (a): Zn concentration = 100% - other element concentration (%)".

Here, when a pre-plated textured steel plate is used as the base textured steel plate, the components of the pre-plating are also detected. For example, when a Ni pre-plated textured steel plate is used, not only the Ni in the plating layer but also the Ni in the Ni pre-plating will be detected in the ICP analysis. Specifically, when a pre-plated textured steel plate with a Ni adhesion amount of 1g/m ² ~3g/m ² (thickness approximately 0.1~0.3µm) is used as the base textured steel plate, even if the Ni contained in the plating layer If the concentration is 0%, the Ni concentration will still be detected at 0.1~15%. Therefore, the Ni concentration in the plating layer may not be clear from the results of ICP analysis. Therefore, when a Ni preplated textured steel sheet is used as the base steel sheet, the Ni concentration in the plating layer is measured by a glow discharge luminescence analysis method (quantitative GDS). Specifically, three or more types of standard samples with different Ni concentrations were used in a high-frequency glow discharge luminescence surface analysis device (manufactured by Horiba Manufacturing Co., Ltd., model: GD-Profiler2) to create a measurement based on the relationship between Ni concentration and Ni luminescence intensity. curve. The standard samples use Zn alloy standard samples IMN ZH1, ZH2, and ZH4 made by BAS. The measurement conditions of GDS are set as follows. HV: Fe is 785V, Ni is 630V, Co is 720V. Anode diameter: φ4mm Gas: Ar Gas pressure: 600Pa Output: 35W Next, use GDS under the above conditions to calculate the 1 of the coating layer of the plated steel to be measured. Ni luminescence intensity at /2 film thickness position. Then, the Ni concentration at the 1/2 position of the plating layer is calculated from the obtained Ni luminescence intensity and the calibration curve created. The so-called 1/2 position of the plating layer is the position at 1/2 time when the Fe intensity reaches saturation, that is, the time to reach the base iron, in the GDS analysis under the above conditions. The determined Ni concentration at the 1/2 position of the plating layer is regarded as the Ni concentration in the plating layer. In this case, the so-called "concentration of other elements (%)" in the above formula (1) for calculating the Zn concentration will be the concentration of elements other than Ni in ICP analysis (%) and the concentration of Ni in GDS analysis (%). total. That is, when Ni pre-plated steel is used as the base steel, the Zn concentration of the plating layer is expressed by "Formula (a'): Zn concentration = 100 - (concentration of elements other than Ni in ICP analysis (%) + Ni concentration (%) in GDS analysis" to calculate. In addition, when a Ni pre-plated textured steel plate is used as the base textured steel plate, when the base textured steel plate is immersed in the plating bath, a trace amount of Ni in the Ni pre-plated layer will be dissolved into the plating bath. Therefore, the Ni concentration in the plating bath will be 0.02~0.03% higher than the Ni concentration in the plating bath after the bath is established. Therefore, when Ni pre-plated reticulated steel plate is used, the Ni concentration in the coating layer will increase by up to 0.03%. Here, the method to determine whether the base textured steel plate is a pre-plated textured steel plate is as follows. A sample is taken from the target corrugated steel plate, and the cross section of the sample cut along the thickness direction of the corrugated steel plate is the measurement surface. For the measurement surface of the sample, the Ni concentration was measured by performing line analysis near the interface between the coating layer in the textured steel plate and the base textured steel plate using an Electron Probe MicroAnalyser: FE-EPMA. The measurement conditions are: accelerating voltage 15kV, beam diameter about 100nm, irradiation time of each point 1000ms and measurement spacing 60nm. In addition, the measurement distance may be a distance at which it can be confirmed whether the Ni concentration in the interface between the plating layer and the base textured steel plate in the textured steel plate is concentrated. Furthermore, if the Ni concentration in the interface between the plating layer and the underlying textured steel plate in the textured steel plate becomes concentrated, the underlying textured steel plate is determined to be a pre-plated textured steel plate.

Next, the Al-Fe alloy layer will be described. An Al-Fe alloy layer is sometimes formed on the surface of the base corrugated steel plate (specifically, between the base corrugated steel plate and the Zn-Al-Mg alloy layer), and in terms of structure, the Al ₅ Fe phase is the main phase. layer. The Al-Fe alloy layer is formed by mutual atomic diffusion between the base corrugated steel plate and the plating bath. Since the reticulated steel plate of the present disclosure forms a coating layer by a hot-dip plating method, an Al-Fe alloy layer is easily formed in the coating layer containing Al element. Moreover, since the plating bath contains Al above a fixed concentration, the Al ₅ Fe phase is formed the most. However, atomic diffusion takes time, and there is also a portion where the Fe concentration increases near the base textured steel plate. Therefore, the Al-Fe alloy layer may locally contain a small amount of AlFe phase, Al ₃ Fe phase, Al ₅ Fe ₂ phase, etc. In addition, since the plating bath also contains a fixed concentration of Zn, the Al-Fe alloy layer also contains a small amount of Zn.

Regarding the corrosion resistance of the Al ₅ Fe phase, the Al ₃ Fe phase, the AlFe phase, and the Al ₅ Fe ₂ phase, there is little difference regardless of which phase they are. The corrosion resistance here refers to the corrosion resistance of parts not affected by welding.

Here, when the plating layer contains Si, Si is particularly easily incorporated into the Al-Fe alloy layer, and an Al-Fe-Si intermetallic compound phase may be formed. As an identifiable intermetallic compound phase, there is the AlFeSi phase, and as isomers, there are α, β, q1, q2-AlFeSi phases, etc. Therefore, in the Al-Fe alloy layer, the AlFeSi may be detected as equal. The Al-Fe alloy layer containing the AlFeSi equivalent is also called an Al-Fe-Si alloy layer. In addition, compared with the Zn-Al-Mg alloy layer, the thickness of the Al-Fe-Si alloy layer is also smaller, so it has less impact on the corrosion resistance of the entire plating layer.

In addition, when various pre-plated textured steel plates are used as the base textured steel plate, the structure of the Al-Fe alloy layer may change due to the amount of pre-plated adhesion. Specifically, there are the following situations: the pure metal layer used for pre-plating remains around the Al-Fe alloy layer; the intermetallic compound phase formed by combining the constituent components of the Zn-Al-Mg alloy layer and the pre-plating components (for example, Al ₃ Ni equal) forms an alloy layer; forms an Al-Fe alloy layer in which Al atoms and part of Fe atoms are substituted; or forms Al-Fe alloy layer in which Al atoms, Fe atoms and part of Si atoms are substituted -The case of Si alloy layer, etc.

That is, the so-called Al-Fe alloy layer is a layer that includes alloy layers of various aspects described above in addition to the alloy layer mainly composed of the Al ₅ Fe phase.

In addition, among various pre-plated corrugated steel sheets, when a plating layer is formed on the Ni pre-plated corrugated steel sheet, an Al-Ni-Fe alloy layer is formed as an Al-Fe alloy layer.

The thickness of the Al-Fe alloy layer is, for example, 0 μm or more and 7 μm or less. From the viewpoint of improving the adhesion of the plating layer (specifically, the Zn-Al-Mg alloy layer) and ensuring corrosion resistance and processability, the thickness of the Al-Fe alloy layer is preferably 0.05 µm or more and 5 µm or less.

The thickness of the Zn-Al-Mg alloy layer is usually thicker than that of the Al-Fe alloy layer. Therefore, compared with the Zn-Al-Mg alloy layer, the Al-Fe alloy layer is more suitable for plating. The corrosion resistance of corrugated steel plate is relatively low. However, as inferred from the composition analysis results, the Al-Fe alloy layer contains corrosion-resistant elements Al and Zn at a fixed concentration or above. Therefore, the Al-Fe alloy layer has a certain degree of corrosion resistance against the base corrugated steel plate.

Furthermore, if a plating layer with a chemical composition specified in this disclosure is formed by a hot-dip plating method, an Al-Fe alloy layer of 100 nm or more will probably be formed between the base corrugated steel plate and the Zn-Al-Mg alloy layer. .

From the viewpoint of corrosion resistance, the thicker the Al-Fe alloy layer, the better. Therefore, the thickness of the Al-Fe alloy layer should be above 0.05µm. However, a thick Al-Fe alloy layer may cause significant deterioration in plating workability, so the thickness should be less than a fixed thickness. From the viewpoint of workability, the thickness of the Al-Fe alloy layer is preferably 7µm or less. If the thickness of the Al-Fe alloy layer is 7µm or less, the amount of cracks and powdering caused by the Al-Fe alloy layer will be reduced, and the workability will be improved. The thickness of the Al-Fe alloy layer is more preferably less than 5µm, and more preferably less than 2µm.

The thickness of the Al-Fe alloy layer is measured as follows. After the sample was embedded in the resin, it was ground, and then in the SEM reflection electron image of the cross-section of the coating layer (the cut surface along the thickness direction of the coating layer) (but, assuming a magnification of 10,000 times, the field of view size: The visual field in which the Al-Fe alloy layer can be identified (50µm in length × 200µm in width), and the thickness of any 5 identified Al-Fe alloy layers is measured. Then, the arithmetic mean of the 5 points was regarded as the thickness of the Al-Fe alloy layer.

(Characteristics of plated corrugated steel plate) -Plating layer thickness ratio of flat part- In the plated corrugated steel plate of the present disclosure, when a thin portion and a thick portion of the plated layer are locally generated in the flat portion, the corrosion resistance will be deteriorated. In addition, processability also deteriorates. Therefore, the thickness ratio of the plating layer in the flat portions on the left and right sides of the convex portion (layer thickness of the left plating layer/thickness of the right plating layer) is set to 0.2 or more and 5.0 or less. From the viewpoint of improving corrosion resistance and workability, the plating layer thickness ratio of the flat portion (thickness of the plating layer on the left/thickness of the plating layer on the right) is preferably 0.25 or more and 4.00 or less, preferably Above 0.33 and below 3.00.

Here, from the viewpoint of corrosion resistance and workability, the thickness of the plating layer on the flat portion is preferably 1.0~300.0µm, and more preferably 2.0~200.0µm.

The plating layer thickness ratio of the flat portion can be measured as follows. First, from the center of the plate surface of the plated corrugated steel plate to be measured, a sample is taken from the center of the longitudinal direction of the convex portion and a cut surface becomes the observation surface. The cut surface is orthogonal to the longitudinal direction of the convex portion and Cut along the thickness direction of the plate (specifically, the cutting surface corresponding to the F-F section in Figure 3A). Next, the sample is embedded in the resin, and the observation surface of the sample is observed with a scanning electron microscope (SEM) at a magnification of 500 times or 2000 times (see FIG. 1A and FIG. 1B ). Next, the thickness of the plating layer on the left and right flat portions is measured, and the ratio of the thickness of the left plating layer/the thickness of the right plating layer is calculated. Here, it is 3 mm away from the boundary between the convex portion and the flat portion (specifically, the edge ends of a pair of parallel flat portions facing each other in the plate thickness direction (refer to EG in Figure 1A)). At (refer to FP in Figure 1), measure the thickness of the plating layer at the left and right flat portions (refer to FT in Figure 1B). In addition, in Figure 1, B represents the base textured steel plate, C represents the plating layer, Q represents the convex part, and P represents the flat part.

This operation was performed on three samples taken at a distance of 100 mm or more from each other, and the arithmetic mean of the "ratio of the thickness of the plating layer on the left/the thickness of the plating layer on the right side" was determined as "the ratio of the flat part" Plating layer thickness ratio".

-Formula 1 and Formula 2- In the plated textured steel plate of the present disclosure, if the texture height T-t represented by the difference between the thickness T of the base textured steel plate in the convex portion and the thickness t of the base textured steel plate in the flat portion is too large, the convex portion and The difference in thermal expansion of the flat portion will become too large. As a result, deformation occurs due to heating and cooling before the immersion plating bath, resulting in deterioration of flatness. Therefore, the texture height T-t is set to be equal to or less than the thickness of the base textured steel plate in the flat portion. On the other hand, in order to ensure the function of the plated corrugated steel plate (such as slip resistance), the corrugated height T-t is limited to be greater than 0.5 mm.

In the plated corrugated steel plate of the present disclosure, when the plated corrugated steel plate is allowed to stand still, if the gap height x from the resting surface is too large, the flatness will deteriorate. Therefore, the gap height x is set to the texture height T-t×1.5 or less.

Furthermore, if the flatness of the plated corrugated steel sheet of the present disclosure deteriorates, the thickness ratio of the plating layer to the flat portions on the left and right sides of the convex portions will increase, and the corrosion resistance and workability will also deteriorate.

Therefore, the texture height T-t and the gap height x must satisfy the following equations 1 and 2; the texture height T-t is: let the thickness of the base texture steel plate in the convex part be T and let the aforementioned base mesh in the flat part The height of the texture when the thickness of the corrugated steel plate is t; the gap height high. Formula 1: x/(T-t)≦1.5 Formula 2: 0.5＜T-t≦t The unit of thickness T, t, and gap height x of the base corrugated steel plate in Formula 1 and Formula 2 is "mm".

In Formula 1, from the viewpoint of improving flatness, improving corrosion resistance, and improving processability, the "x/(T-t)" value is preferably 1.2 or less, and more preferably 1.0 or less. In addition, from the same point of view, the value of "x/(T-t)" should be close to 0. In Formula 2, from the viewpoint of improving flatness, corrosion resistance and processability, the "T-t" value is preferably 0.8t or less, and more preferably 0.7t or less. In addition, the lower limit of the texture height T-t is set considering improving the function of the plated textured steel plate (such as slip resistance).

Here, the thickness t of the base corrugated steel plate in the flat part is preferably 1.6~6.0mm. From the viewpoint of flatness, corrosion resistance and workability, the gap height x is preferably 3.0 mm or less, more preferably 2.0 mm or less. In addition, if the function of the plated textured steel plate (such as skid resistance) is considered, the area occupancy of the convex portion (that is, the textured portion) should be 15 to 60%.

The thickness T of the base textured steel plate in the convex part, the thickness t of the base textured steel plate in the flat part, the texture height T-t, and the gap height x can be measured as follows.

First, a 300mm square sample is taken from the center of the plate surface of the plated corrugated steel plate to be measured. Next, the collected sample is placed still on a horizontal surface (standing surface). Among them, the surface of the sample opposite to the resting surface is defined as: the surface equivalent to the surface of the plated textured steel plate without convex parts and flat parts. Observe the resting sample from a direction horizontal to the resting surface, and measure the height of the gap between the resting surface and the plate surface of the specimen opposite to the resting surface (see Figure 2). Furthermore, this operation is performed from the directions of the four sides of the sample, and the maximum value of the gap height is regarded as the gap height x. Here, in Figure 2, CS represents the sample of the plated corrugated steel plate, and Su represents the resting surface.

On the other hand, from a 300mm square sample, take a cut surface at the center of the long side direction of the convex part to become the observation surface. The cut surface is orthogonal to the long side direction of the convex part and cut along the plate thickness direction. (specifically, it is the cutting plane corresponding to the F-F section in Figure 3A). Next, the sample was embedded in the resin, and the observation surface of the sample was observed with an optical microscope at a magnification of 25 times (see Figure 1). Next, the thickness of the base textured steel plate in the width direction center portion of the convex portion and the thickness of the base textured steel plate in the width direction center portion of the flat portion were measured respectively.

Furthermore, this operation was carried out for three samples, and the maximum value of the obtained "thickness of the base corrugated steel plate in the width direction center part of the convex part" and "the thickness of the base corrugated steel plate in the width direction center part of the flat part" was The values are respectively determined as the thickness T of the base textured steel plate in the convex part and the thickness t of the base textured steel plate in the flat part, and the difference between them is the texture height T-t.

(Manufacturing method of plated corrugated steel plate) Hereinafter, an example of the manufacturing method of the plated corrugated steel plate of this disclosure is demonstrated.

This disclosure discloses a method for manufacturing a plated corrugated steel plate. For example, the base corrugated steel plate is heated to a plating bath temperature of +20°C or above and below 850°C at a heating rate of 5~20°C/second and maintained, and then cooled at a cooling rate of 5~20°C/second. 20℃/second, cool it to a range above the plating bath temperature and below the plating bath temperature +10℃, and then immerse the cooled base textured steel plate in the plating bath. After taking it out from the plating bath, if it is plated When the bath temperature is higher than 500°C, the plated reticulated steel plate is produced by cooling to 500°C at a cooling rate of 5~20°C/second. Here, the plating is implemented by a continuous molten metal plating method such as the Sendzimir method.

An example of a specific manufacturing method is as follows. First, prepare a base textured steel plate whose texture height T-t satisfies Equation 1. Next, after the base corrugated steel plate is pickled, the base corrugated steel plate is heated and maintained at the heating temperature. Here, pre-plating (such as Ni pre-plating) may also be performed on the base corrugated steel plate after pickling and before heating.

The heating reaching temperature is set to be above the plating bath temperature + 20°C and below 850°C. By setting the heating reaching temperature below 850°C to suppress the deformation of the base corrugated steel plate, the flatness will be improved. The heating speed is set at 5~20℃/second. By heating gently at a heating rate of 20°C/second or less, the convex portions and flat portions of the base corrugated steel plate will heat up evenly, thereby suppressing deformation caused by the difference in thermal expansion between the convex portions and the flat portions. As a result, further deterioration of flatness is suppressed. On the other hand, if the heating speed is too slow, it will be difficult for the convex portion and the flat portion of the base corrugated steel plate to heat up uniformly, and deformation caused by the difference in thermal expansion between the convex portion and the flat portion will easily occur. Therefore, the heating rate is set to 5°C/sec. Without pre-plating, the heating maintenance time is set to 10 to 120 seconds. By setting the heating maintenance time to 10 to 120 seconds, the oxide film on the surface can be restored and the plating properties can be improved.

The base corrugated steel plate is heated by, for example, electric heating, non-oxidation direct heating, or radiation heating.

Next, the base corrugated steel plate is cooled to a range above the plating bath temperature and below the plating bath temperature +10°C. The cooling rate is set at 5~20℃/second. By cooling gently at a cooling rate of 20°C/sec or less, the convex portions and flat portions of the base corrugated steel plate are cooled evenly, and deformation caused by the difference in thermal shrinkage between the convex portions and the flat portions is suppressed. As a result, further deterioration of flatness is suppressed. On the other hand, if the cooling rate is too slow, it will be difficult for the convex portion and the flat portion of the base corrugated steel plate to be cooled uniformly, and deformation caused by the difference in thermal shrinkage between the convex portion and the flat portion will easily occur. Therefore, the cooling rate is set to 5°C/sec.

The base corrugated steel plate is cooled, for example, by nitrogen cooling.

By heating and cooling the base textured steel plate before plating in the above manner, deterioration in flatness is suppressed, and therefore a plated textured steel plate having a gap height x that satisfies Equation 2 can be obtained.

Next, the cooled base corrugated steel plate is immersed in a plating bath. The chemical composition of the plating bath is equivalent to the chemical composition of the plating layer in the plated corrugated steel plate disclosed above.

Next, after the base corrugated steel plate is taken out from the plating bath, the plating adhesion amount is adjusted by wiping and then cooled. When the plating bath temperature is below 500°C, there are no special restrictions on the cooling conditions after plating. On the other hand, when the plating bath temperature is higher than 500°C, the cooling rate to 500°C after plating is set to 5 to 20°C/second. By cooling gently at a cooling rate of 20°C/sec or less, the convex portions and flat portions of the base corrugated steel plate are cooled evenly, and deformation caused by the difference in thermal expansion between the convex portions and the flat portions is suppressed. As a result, further deterioration of flatness is suppressed. On the other hand, if the cooling rate is too slow, it will be difficult for the convex portion and the flat portion of the base corrugated steel plate to be cooled uniformly, and deformation caused by the difference in thermal expansion between the convex portion and the flat portion will easily occur. Therefore, the cooling rate is set to 5°C/sec. In addition, there are no special restrictions on cooling conditions below 500°C. Cooling after plating is performed by, for example, air cooling or nitrogen cooling.

Here, if the flatness of the base textured steel plate is poor, when wiping after plating, the distance between the wiping nozzel and the base textured steel plate will change depending on the position, so local plating will occur. Where the layer is thinner and where it is thicker, the thickness of the plating layer will vary between the flat parts. In addition, when gas cooling is performed, the distance between the cooling nozzle and the base corrugated steel plate will also change depending on the position, so there will be local thinner and thicker areas of the plating layer, thereby plating between the flat parts. Layer thickness will vary. In particular, compared with Zn-based plating baths, Zn-Al-Mg alloy-based plating baths have lower viscosity, so the thickness of the plating layer is prone to unevenness.

However, since further deterioration of the flatness of the base patterned steel sheet has been suppressed during heating and cooling before the immersion plating bath as described above, even if Zn-Al-Mg-based plating is performed, the plating layer will remain between the flat portions. The layer thickness is not easy to vary, and a Zn-Al-Mg-based plated mesh steel plate can be obtained. The ratio of the thickness of the coating layer to the flat parts on the left and right of the convex part (the thickness of the coating layer on the left side/the thickness of the coating layer on the right side) layer thickness) meets the above range.

The following describes the subsequent processing that can be applied to the plated corrugated steel plate of the present disclosure.

The plated corrugated steel plate of the present disclosure can also form a film on the plating layer. Can form 1 layer or more than 2 layers of film. Examples of types of coatings directly above the plating layer include chromate coatings, phosphate coatings, and chromate-free coatings. The chromate treatment, phosphate treatment and chromate-free treatment used to form the film can be performed by known methods.

Chromate treatment includes the following: electrolytic chromate treatment, which forms a chromate film through electrolysis; reactive chromate treatment, which uses reaction with the material to form a film and then washes off the excess treatment liquid; Coating-type chromate treatment is applied to the object to be coated and then dried without washing to form a film. Either treatment can be used.

Examples of the electrolytic chromate treatment include the following electrolytic chromate treatment: chromic acid, silica oxide sol, resin (acrylic resin, vinyl ester resin, vinyl acetate acrylic emulsion, carboxylated styrene butadiene latex, diamine Isopropylamine modified epoxy resin, etc.) and hard silicon oxide.

Examples of the phosphate treatment include zinc phosphate treatment, zinc calcium phosphate treatment, and manganese phosphate treatment.

Chromate-free treatment is particularly suitable as it does not place a load on the environment. There are two types of chromate-free treatment: electrolytic chromate-free treatment, which forms a chromate-free film through electrolysis; and reactive chromate-free acid, which forms a film by reacting with the material and then washes away the excess treatment solution. Salt treatment: a coating type chromate-free treatment in which the treatment liquid is applied to the object to be coated and then dried without washing to form a film. Either treatment can be used.

It is also possible to further have one or more layers of organic resin films on the film directly above the plating layer. The organic resin is not limited to a specific type, and examples thereof include polyester resin, polyurethane resin, epoxy resin, acrylic resin, polyolefin resin or modified products of these resins. The so-called modified product here refers to the resin after reacting the reactive functional groups contained in the structure of the resin with other compounds (monomers or cross-linking agents, etc.). The other compounds are contained in the structure and can be combined with The functional group is a functional group that reacts.

As the organic resin, one type or a mixture of two or more types of organic resins (without modification) may be used, or at least one other type of organic resin may be modified in the presence of at least one type of organic resin. , use one type of organic resin thus obtained or mix two or more types of the obtained organic resins. In addition, the organic resin film may contain any color pigment or anti-rust pigment. Those dissolved or dispersed in water to become water-based can also be used.

Example The embodiments of the present disclosure will be described. However, the conditions in the embodiments are examples of conditions adopted to confirm the feasibility and effects of the present disclosure, and the disclosure is not limited to this example of conditions. Various conditions may be adopted for this disclosure as long as the purpose of cost disclosure is achieved without departing from the gist of this disclosure.

(Example) In order to obtain a plating layer with the chemical composition shown in Tables 1 to 2, a predetermined amount of pure metal ingot is used, and a plating bath is established in the atmosphere after melting the ingot. Batch-type molten plating equipment is used in the production of plated textured steel plates.

Then, a plated textured steel plate was produced under the conditions shown in Table 1 to Table 2. Specifically, it is as follows. In an N ₂ -H ₂ (5%) (dew point below -40°C, oxygen concentration less than 25 ppm) environment, use electrical heating to heat the base corrugated steel plate from room temperature, and then blow N ₂ gas after maintaining it for 60 seconds. The steel plate was cooled to the plating bath temperature +10°C and then immediately immersed in the plating bath. After that, the base textured steel plate is taken out from the plating bath, and the N ₂ gas wiping pressure is adjusted so that the plating adhesion amount on the plate surface with convex parts and flat parts becomes about 250g/m ² to create a plating texture. steel plate.

In addition, as the base textured steel plate, various hot-rolled textured steel plates having different plate thicknesses T in the convex portions and plate thickness t in the flat portions are used. The shape of the base corrugated steel plate used is the same as Figure 3A~Figure 3C. In the figure, A, B, C, D, E and H are each as follows. A: The arrangement angle of the convex parts relative to the rolling direction. B: The length of one convex part. C: The maximum width of one convex part. D: The minimum width of a convex part. E: The arrangement spacing of the convex parts. H: Height of convex portion (that is, height of mesh). The reticulated steel plate is hot-rolled aluminum deoxidized steel, with angle A=45°, length B=25.3mm, maximum width C=5.1mm, minimum width D=2.5mm, and spacing E=28.6mm. In addition, the area occupancy rate of the convex portion is 40%. However, the convex portion height H (that is, the texture height T-t) is determined as shown in Table 1.

In some examples, a Ni pre-plated textured steel plate obtained by subjecting the hot-rolled textured steel plate to Ni pre-plating is used as the base textured steel plate. The Ni adhesion amount is set at 1g/m ² ~3g/m ² . In addition, for the example of using Ni pre-plated textured steel plate as the base textured steel plate, mark it as "Pre-Ni" in the "Base textured steel plate" column in the table.

-Various measurements- Regarding the obtained plated corrugated steel plate, the following matters were measured according to the methods described above. ・The thickness ratio of the plating layer in the flat parts on the left and right sides of the convex part (layer thickness of the plating layer on the left side / layer thickness of the plating layer on the right side) ・Thickness T of the base corrugated steel plate in the convex part (marked as "Thickness T of the convex part" in the table) ・Thickness t of the base corrugated steel plate in the flat part (marked as "flat part thickness t" in the table) ・Gap height x

-flatness- In order to compare the flatness, the sample was placed on a flat platform and the degree of shaking was evaluated by pressing the sample from above. When there is no shaking, it is rated as "A+", when there is slight shaking, it is rated as "A", and when there is severe shaking, it is rated as "NG".

-Corrosion resistance- In order to compare the corrosion resistance, the manufactured samples were subjected to the corrosion promotion test (JASO M609-91) for 30 cycles, and then the average value of the area ratio of red rust generation was evaluated. If the area rate of red rust is 3.0% or less, it will be rated as "A+", if it is less than 5.0%, it will be rated as "A", if it is less than 7.0%, it will be rated as "B", and if it is more than 7.0%, it will be rated as "NG".

-Processability- In order to evaluate the processability of the coating layer, the plated corrugated steel plate was bent in a 90° V-shape with the plate surface provided with convex parts and flat parts as the peak side, and a cellophane tape with a width of 24 mm was pressed against the V Then tear off the curved peak of the word. The area ratio of the plating layer torn off from the plated corrugated steel plate and attached to the cellophane tape relative to the area of the pressed cellophane tape is 3.0% or less and is rated as "A+", and 5.0% or less is rated as "A" ”, if it is less than 10.0%, it will be rated as “B”, and if it is more than 10.0%, it will be rated as “NG”.

Examples are listed in Tables 1 to 2.

[Table 1-1]

[Table 1-2]

[Table 1-3]

[Table 1-4]

[table 2-1]

[Table 2-2]

[Table 2-3]

[Table 2-4]

From the above results, it can be seen that compared with the comparative examples, the examples of the plated mesh steel plates according to the present disclosure are superior in flatness, corrosion resistance and workability.

In addition, Test No. 97 (Comparative Example) is an example in which the heating reaching temperature before plating is as high as 850°C or more. Test No. 98 (comparative example) is an example in which the heating rate before plating is as high as 30°C/second. Test No. 99 (comparative example) is an example in which the cooling rate after heating before plating is as high as 30° C./second. Test No. 100 (comparative example) is an example in which the heating rate before plating and the cooling rate after heating before plating are as high as 30°C/sec. Test No. 101 (comparative example) is an example in which the cooling rate after plating is as high as 30°C/sec. Test No. 102 (comparative example) is an example in which T-t is as large as plate thickness t or more. Test Examples No. 103 (Comparative Example) to No. 105 (Comparative Example) are examples in which the heating rate before plating, the cooling rate after heating before plating, and the cooling rate after plating are slow. These test Nos. 97~103 all meet the plating layer composition disclosed in this disclosure. However, the plating layer thickness ratio and "x/(T-t)" value of the flat part are large, so the flatness, corrosion resistance and processability are deteriorated. .

As above, the preferred implementation forms and examples of the present disclosure have been described in detail with reference to the accompanying drawings, but the present disclosure is not limited to the examples. It should be understood that any person with common knowledge in the technical field to which this disclosure belongs can contemplate various modifications or amendments within the scope of the technical ideas recorded in the scope of the patent application, and be aware that these should also be included in this disclosure. Reveal the technical scope.

B: Base textured steel plate C:plated layer Q:convex part P: flat part T: Thickness of the base corrugated steel plate in the convex part t: Thickness of the base corrugated steel plate in the flat part x: gap height CS: Sample of plated corrugated steel plate EG: The boundary between the convex part and the flat part FP: 3mm away from the boundary between the convex part and the flat part FT: The thickness of the plating layer in the flat part Su:Still noodles A: The arrangement angle of the convex parts relative to the rolling direction (Figure 3A~Figure 3C) B: The length of one convex part (Figure 3A~Figure 3C) C: The maximum width of one convex part (Figure 3A~Figure 3C) D: Minimum width of one convex part (Figure 3A~Figure 3C) E: Arrangement spacing of convex parts (Figure 3A~Figure 3C) H: Height of convex portion (Figure 3A~Figure 3C)

Figure 1A is a SEM photograph (500 times) showing an example of a cross-section of the Zn-Al-Mg based plated mesh steel plate of the present disclosure. Figure 1B is an SEM photograph (2000 times) showing an example of the cross-section of the Zn-Al-Mg based plated corrugated steel plate of the present disclosure. Figure 2 is a schematic diagram illustrating the method for measuring the gap height x in the Zn-Al-Mg based plated mesh steel plate of the present disclosure. 3A is a schematic top view showing an example of the base corrugated steel plate of the Zn-Al-Mg based plated corrugated steel plate of the present disclosure. FIG. 3B is a schematic cross-sectional view showing an example of the base corrugated steel plate of the Zn-Al-Mg based plated corrugated steel plate of the present disclosure, and is a schematic cross-sectional view of G-G in FIG. 3A . FIG. 3C is a schematic cross-sectional view showing an example of the base corrugated steel plate of the Zn-Al-Mg based plated corrugated steel plate of the present disclosure, and is a schematic cross-sectional view taken along line F-F of FIG. 3A .

B: Base textured steel plate

C:plated layer

Q:convex part

P: flat part

T: Thickness of the base corrugated steel plate in the convex part

t: Thickness of the base corrugated steel plate in the flat part

EG: The boundary between the convex part and the flat part

FP: 3mm away from the boundary between the convex part and the flat part

FT: The thickness of the plating layer in the flat part

Claims (3)

A Zn-Al-Mg based plated corrugated steel plate, which has a base corrugated steel plate and a plating layer. The base corrugated steel plate is provided with a convex part and a flat part on one of the plate surfaces. The plating layer is arranged on the aforementioned The surface of the base corrugated steel plate is provided with convex parts and flat parts, and the plating layer includes a Zn-Al-Mg alloy layer; The aforementioned plating layer has a chemical composition consisting of: In mass %, Zn: greater than 65.0%, Al: greater than 1.0% and less than 25.0%, Mg: greater than 1.0% and less than 12.5%, Sn: 0%~5.0%, Bi: 0%~less than 5.0%, In: 0%~less than 2.0%, Ca: 0%~3.00%, Y: 0%~0.5%, La: 0%~less than 0.5%, Ce: 0%~less than 0.5%, Si: 0%~less than 2.5%, Cr: 0%~less than 0.25%, Ti: 0%~less than 0.25%, Zr: 0%~less than 0.25%, Mo: 0%~less than 0.25%, W: 0%~less than 0.25%, Ag: 0%~less than 0.25%, P: 0%~less than 0.25%, Ni: 0%~less than 0.25%, Co: 0%~less than 0.25%, V: 0%~less than 0.25%, Nb: 0%~less than 0.25%, Cu: 0%~less than 0.25%, Mn: 0%~less than 0.25%, Li: 0%~less than 0.25%, Na: 0%~less than 0.25%, K: 0%~less than 0.25%, Fe: 0%~5.0%, Sr: 0%~less than 0.5%, Sb: 0%~less than 0.5%, Pb: 0%~less than 0.5%, B: 0%~less than 0.5% and impurities; At the central portion of the longitudinal direction of the convex portion, observe the cut surface obtained by cutting along the plate thickness direction and perpendicular to the longitudinal direction of the convex portion. At this time, the plating layer of the flat portion on the left and right of the convex portion The layer thickness ratio (layer thickness of the left plating layer/layer thickness of the right plating layer) is 0.2 or more and 5.0 or less; and The texture height T-t and the gap height x satisfy the following formulas 1 and 2; the texture height T-t is: let the thickness of the aforementioned base texture steel plate in the aforementioned convex part be T and let the aforementioned base texture in the aforementioned flat part The height of the texture when the thickness of the steel plate is t; the gap height ; Formula 1: x/(T-t)≦1.5; Formula 2: 0.5＜T-t≦t; The unit of thickness T, t, and gap height x of the base corrugated steel plate in Formula 1 and Formula 2 is "mm". For example, the Zn-Al-Mg plated corrugated steel plate of claim 1, wherein the Al concentration is greater than 5.0% and less than 25.0%, and the Mg concentration is greater than 3.0% and less than 12.5%. For example, the Zn-Al-Mg plated corrugated steel plate of Claim 1 or Claim 2, wherein the aforementioned coating layer includes an Al-Fe alloy layer between the aforementioned base corrugated steel plate and the aforementioned Zn-Al-Mg alloy layer. .