KR102073291B1 - Measuring method of phosphate coverage - Google Patents

Abstract

One embodiment of the present invention is a step of performing a phosphate treatment on the substrate, performing a copper plating on the phosphate-treated substrate to form a copper plating on the phosphate crystal unformed region, and the phosphate crystal formation region of the entire area Comprising a step of calculating the phosphate coverage by calculating the area ratio provides a method for measuring phosphate coverage comprising a.

Description

How to measure phosphate coverage {MEASURING METHOD OF PHOSPHATE COVERAGE}

The present invention relates to a method for evaluating electrodeposition coating pretreatment and a method for measuring phosphate coverage.

Metals are concerned about oxidation, ie corrosion. Therefore, in order to prevent corrosion, the automobile company carries out painting. However, since the metal surface has no bonding strength with organic coating, a special treatment for improving the bonding strength is required. An exemplary approach is phosphate treatment. Phosphate treatment is a way to improve the surface area by forming micro-level crystals on the metal surface. When painting the phosphate-treated steel sheet, the coating penetrates between the phosphate crystals, thereby securing excellent paint adhesion.

Since the paint adhesion is also directly linked to the corrosion resistance of the coating, the coating adhesion and the corrosion resistance can be predicted only by the phosphate quality. Measures of phosphate quality include 1) appearance, 2) uniformity, 3) coverage, 4) crystal size, 5) adhesion amount, and 6) P-ratio.

Appearance refers to the degree of surface uniformity at the neck side after phosphate treatment, and uniformity mainly refers to the shape uniformity of crystals in the optical image. Coverage is determined by the presence or absence of crystals covering the surface of the steel sheet and determined by the neck side. The crystal size means the average of the size of the crystal growth direction by selecting the three largest crystals in the optical high magnification image. Amount of adhesion refers to the number of grams of phosphate attached in a certain area, and there is a wet / dry analysis method. P-ratio is a measure of the degree of formation of phosphophyllite and phosphophyllite in the phosphate crystal structure, Phosphophyllite and Hopite, and considering the electrodeposition coating process, ) As the decision is appropriate for long-term quality, quality is determined by ratio checking.

Among the six quality factors, items that can be reflected by the evaluator's subject are 1) appearance, 2) uniformity, and 3) coverage, and there is a need for an easier and objective way to evaluate phosphate quality.

The present invention is to provide a phosphate coverage measurement method that can reduce the deviation between the measurement through the ease and quantification of phosphate coverage evaluation.

The phosphate coverage measuring method according to an embodiment of the present invention comprises the steps of: phosphate treatment on the substrate, copper plating on the phosphate-treated substrate to form a copper plating on the phosphate crystal unformed region, and the total area Computing the ratio of the area of the phosphate crystal forming region to the phosphate coverage may be included.

The method may further include photographing the copper-plated surface using optical equipment after performing copper plating on the phosphate-treated substrate to form copper plating on the phosphate crystal unformed region.

After photographing the copper plated surface using the optical equipment, the method may further include creating an extracted image for displaying the optical image by distinguishing the copper plating forming region and the unformed region by color.

Creating an extracted image displaying the optical image by dividing the copper plating formation region and the unformed region by color may further include maximizing color contrast between the copper plating formation region and the unformed region in the optical image. have.

The copper plating may be performed on the phosphate treated substrate to form copper plating on the phosphate crystal unformed region at 45 to 50 ° C.

The copper plating may be performed on the phosphate-treated substrate to form copper plating in the phosphate crystal unformed region for 1 to 5 seconds.

Forming copper plating on the phosphate crystal formation region by performing copper plating on the phosphate-treated substrate may be performed by using a solution containing at least one material selected from copper cyanide, copper sulfate, or copper pyrophosphate. have.

The molarity of the copper solution may be 1M to 5M.

In the step of forming copper plating on the phosphate crystal non-forming region by performing copper plating on the phosphate-treated substrate, the thickness of the copper plating layer may be formed to 3 to 12 μm.

In the photographing of the copper plated surface using the optical equipment, the optical equipment may be performed by SEM or EPMA.

Creating an extracted image displaying the optical image by dividing the copper plating formation region and the unformed region by color may include coloring any one of the copper plating formation region or the unformed region by using an image analyzer. It may be.

In the optical image, maximizing color contrast between the copper plating forming region and the unforming region may include converting one of the copper plating forming region and the unforming region into white or black.

The present invention can quantify the method for evaluating phosphate coverage to measure phosphate coverage without deviation between operators.

1 is a schematic diagram of a phosphate coverage measurement method according to an embodiment of the present invention.
2 is an image when copper plating is performed according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, the present invention is not limited to the embodiments disclosed below can be implemented in a variety of different forms, only the embodiments are to make the disclosure of the present invention complete, the present invention It is provided to fully alert those skilled in the art to the scope of the invention, and the invention is defined only by the scope of the claims.

Thus, in some embodiments, well known techniques are not described in detail in order to avoid obscuring the present invention.

Throughout the specification, the singular forms “a”, “an” and “the” include plural forms unless the context clearly indicates the opposite.

Throughout the specification, when a part is said to "include" a certain component, it means that it may further include other components, except to exclude other components unless specifically stated otherwise.

When a portion of a layer, film, region, plate, or the like is said to be "on" or "on" another portion, this includes not only the case where the other portion is "right over" but also another portion in the middle. In addition, in the specification, "on" means to be located above or below the target portion, and does not necessarily mean to be located above the gravity direction.

All terms including technical terms and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Commonly defined terms used are additionally interpreted as having a meaning consistent with the related technical literature and the presently disclosed contents, and are not interpreted as ideal or very formal meaning unless defined. For example, mixing is used in the same sense as formulation.

The phosphate coverage measuring method according to an embodiment of the present invention comprises the steps of: performing a phosphate treatment on the substrate, performing a copper plating on the phosphate-treated substrate to form a copper plating on the phosphate crystal unformed region, and the total area It provides a phosphate coverage measuring method comprising the step of calculating the phosphate coverage by calculating the area ratio of the phosphate crystal formation region to.

When copper plating is performed on the phosphate-treated substrate, copper plating is formed in the region where the phosphate crystal is not formed, and the copper plating formed is red, so that the region where the phosphate crystal is formed and the region where it is not formed are easily contrasted. It can be clearly distinguished.

2 shows an image when copper plating is performed according to an embodiment of the present invention.

Figure 2 (a) is a photograph when the copper plating is performed on the surface where the phosphate is formed, it can be seen that the copper plating layer is not formed in the portion where the phosphate is formed to have an off-white.

On the other hand, Figure 2 (b) is a photograph when the copper plating is performed on the surface where the phosphate is not formed, it can be seen that the copper plating layer is formed on the surface is not formed phosphate is red. By copper plating on the phosphate-treated substrate as described above, it can be seen that the phosphate treatment can be clearly distinguished by the naked eye.

The substrate may be a steel sheet.

The phosphate coverage is calculated by the formula

Phosphate Coverage = Area / Total Area of Phosphate Formation Area * 100

In the method for measuring phosphate coverage according to an embodiment of the present invention, after the copper plating is performed on the phosphate-treated substrate to form copper plating on the phosphate crystal unformed region, the copper-plated surface by using optical equipment Photographing; may further include. By using the optical image in this way, the ease of area estimation can be improved for the phosphate crystal formation region and / or the crystal non-forming region, and the area calculation step can be more quantified by using various calculation programs.

In the case of the phosphate coverage measurement method according to an embodiment of the present invention, the deviation between the measurers, which is a problem of the conventional coverage measurement method by the neck side, can be eliminated, and there is an advantage of obtaining a quantified phosphate coverage value. .

After photographing the copper plated surface by using the optical equipment, the method may further include creating an extracted image for displaying the optical image by separating the copper plating forming region and the unformed region into colors. Specifically, color separation may be facilitated by creating an extracted image by coloring the region where the phosphate crystal is formed and / or the region where the phosphate crystal is not formed on the image. In this case, errors in the phosphate coverage evaluation can be reduced by improving the ease and clarity of area discrimination.

Creating an extracted image displaying the optical image by dividing the copper plating formation region and the unformed region into colors may further include maximizing color contrast between the copper plating formation region and the unformed region in the optical image. .

Specifically, maximizing the color contrast of the copper plating formation region and the unformed region in the optical image may be by a method of converting the copper plating unformed region to white. In this step, contrast, brightness and minute color difference due to surface curvature caused by phosphate crystal and crystal size of phosphate crystal on the optical image can be eliminated, and the optical image is divided into two regions of the phosphate crystal and the unformed region. Therefore, it is possible to reduce the error of phosphate coverage estimation due to the fine brightness and color difference appearing on the optical image.

However, the present invention is not limited to the method of converting the copper plating forming region to white, and the color converting region may be a copper plating forming region and / or an unformed region. The color conversion is not limited to converting to white, and an appropriate color may be selected and applied in order to easily contrast with the area to be distinguished.

The imaging may be performed by SEM or EPMA in the step of photographing the copper plated surface using the optical equipment. In the case of optical equipment, since it is not a vacuum equipment, measurement time can be saved, and pretreatment is unnecessary.

Creating an extracted image displaying the optical image by dividing the copper plating forming region and the unformed region by color may be performed by using an image analyzer to automatically display an area, or by using a powerpoint. Can be performed by However, the image analyzer has an advantage of reducing the error between the measurement and the time required for the measurement.

Maximizing the color contrast of the copper plating forming region and the unformed region in the optical image

This can be done by automatically displaying the area using an image analyzer or by manually displaying the area using Powerpoint. However, the image analyzer has an advantage of reducing the error between the measurement and the time required for the measurement.

Forming the copper plating may be to form a copper plating by immersing the steel plate in a copper solution for a predetermined time. However, the copper plating method is not limited thereto.

Forming copper plating on the phosphate crystal formation region by performing copper plating on the phosphate treated substrate may be performed using a solution containing at least one material selected from copper cyanide, copper sulfate, or copper pyrophosphate. .

The copper solution means that the copper is present in an ionized state in the solvent.

The molarity of the solution may be 1M to 5M, there is an advantage that can be prevented over plating and uniform plating when the concentration of the solution satisfies the above range.

Forming the copper plating may be performed at a temperature range of 45 to 50 ° C., and if the range is satisfied, plating may be performed in a short time.

The forming of the copper plating may be performed for 1 to 5 seconds, and the copper plating layer having a sufficient thickness may be formed if the above range is satisfied.

The forming of the copper plating may form a copper plating layer thickness of 3 to 12 μm. When the copper plating layer is satisfied, a sufficient color difference with the copper plating unformed region may be formed and the over plating may be prevented. There is an advantage to that.

Hereinafter, preferred examples and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited to the following examples.

Example

The plate was treated with phosphate at 40 ° C., 90 sec, and dipping using SD2800 (NIPPON PAINT Co., Ltd.).

Under atmospheric pressure, the phosphate-treated steel sheet was immersed in an aqueous solution of copper sulfate at 45 ° C. for 5 seconds, dried for 10 minutes in a 100 ° C. oven after washing with D.I.W for 10 seconds to form a copper plating layer having a thickness of 10 μm.

Then, the SEM image of the copper plated surface was taken, it can be seen that the portion of the phosphate crystal is not formed, the copper plating layer is formed to appear in red. Thereafter, an image analyzer was used to prepare an extracted image by coloring a region in which the phosphate crystals were not formed on the SEM image in high red, and copper plating was formed by converting the region where the phosphate crystals were formed into white using an image analyzer. The color contrast of the region and the unformed region was maximized. The phosphate coverage was calculated by calculating the area of the phosphate crystal forming region (copper plating unformed region) relative to the total area using the image analyzer of the image that has undergone the color contrast maximization step. Through the above process it was confirmed that the phosphate coverage of the steel sheet surface can be calculated quantitatively.

The present invention is not limited to the above embodiments, but may be manufactured in various forms, and a person of ordinary skill in the art to which the present invention pertains does not change the technical spirit or essential features of the present invention. It will be appreciated that the present invention may be practiced as. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

Claims (12)

Phosphating the substrate;
Performing copper plating on the phosphate treated substrate to form copper plating in the phosphate crystal unformed region;
Photographing the copper plated surface using optical equipment;
Creating an extracted image displaying the optical image by dividing the copper plating forming region and the unformed region by color; And
Calculating a phosphate coverage by calculating an area ratio of the phosphate crystal forming region to the total area;
In the photographing of the copper plated surface using the optical equipment, the optical equipment is SEM or EPMA,
Creating an extracted image displaying the optical image by dividing the copper plating formation region and the unformed region by color may further include maximizing color contrast between the copper plating formation region and the unformed region in the optical image.
How to measure phosphate coverage.
delete delete delete The method of claim 1,
Performing copper plating on the phosphate-treated substrate to form copper plating in the phosphate crystal unformed region
Performed at 45 to 50 ° C
How to measure phosphate coverage.
The method of claim 1,
Performing copper plating on the phosphate-treated substrate to form copper plating in the phosphate crystal unformed region
Performed for 1 to 5 seconds
How to measure phosphate coverage.
The method of claim 1,
Performing copper plating on the phosphate-treated substrate to form copper plating in the phosphate crystal unformed region
Performed using a copper solution containing at least one material selected from copper cyanide, copper sulfate, or copper pyrophosphate
How to measure phosphate coverage.
The method of claim 7, wherein
The molar concentration of the copper solution is 1M to 5M
How to measure phosphate coverage.
The method of claim 1,
Performing copper plating on the phosphate-treated substrate to form copper plating in the phosphate crystal unformed region
Copper plating layer thickness is to be formed to 3 to 12 ㎛
How to measure phosphate coverage.
delete The method of claim 1,
Creating an extracted image displaying the optical image by dividing the copper plating forming region and the unformed region by color.
Coloring an area of either a copper plating formation region or an unformed region using an image analyzer
How to measure phosphate coverage.
The method of claim 1,
Maximizing the color contrast of the copper plating forming region and the unformed region in the optical image
Color converting either the copper plating forming region or the unforming region into white or black;
How to measure phosphate coverage.

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