CN211756625U - Imitation copper wire drawing plate - Google Patents

Abstract

The utility model discloses a copper-imitated wire drawing plate, which comprises a metal substrate, and a chromizing layer, an interface layer, a primer layer, a copper-imitated finish paint layer, a wire drawing layer and a protective layer which are sequentially stacked on the metal substrate; wherein the interface layer is a copper layer which is cold sprayed on the chromized layer, the thickness of the interface layer is 1.6-3.0 mu m, and the cold spraying material is copper powder with the average grain diameter of 1.5 mu m. Based on the utility model discloses an imitative copper drawing board, it paints system and metal substrate to have better adhesive force within a definite time.

Description

Imitation copper wire drawing plate

Technical Field

The utility model relates to an imitative copper drawing board.

Background

Because the copper storage capacity is small in China and the price of copper is relatively expensive, in China, copper imitation paint is usually sprayed on metal substrates such as iron substrates and aluminum substrates based on a copper imitation process to prepare a copper imitation layer, so that the prepared plate body has the appearance of a copper plate.

An important index for evaluating the performance of a copper-like plate is the service life of the copper-like plate, and one index directly related to the service life is the bonding force between the copper-like paint and a substrate, generally speaking, the copper-like paint is used as a finishing paint, and in order to improve the adhesion capability of the copper-like paint, the substrate is generally required to be pretreated, a primer is sprayed on the substrate, and then the finishing paint is sprayed on the primer, so that the paint layer on the substrate is generally a multi-layer paint film, which is also called a paint system, and for a high-quality paint system, each paint layer is basically necessary, and each paint layer has different functions.

Typically, chinese patent document CN207140647U discloses a copper-like drawing and printing board, wherein the paint film substantially comprises four layers, from the inside to the outside of the metal substrate layer, a transparent copper-like primer layer, a drawing and printing pattern layer, a finishing paint layer and a protective film layer, in other words, only a primer and no finishing paint are provided in the patent document. However, it is well known in the art that primers are often used as the first layer of a multi-layer paint film, and their primary function is to improve the adhesion of the top coat, increase the fullness of the top coat, provide alkali resistance, provide corrosion protection, etc., while ensuring uniform absorption of the top coat for optimal performance of the paint system. The finish paint is mainly focused on the final decoration and appearance effect, the adhesion between the finish paint and metal is often insufficient, and the adhesion between the finish paint and other paint layers of a paint layer system is often better, which is why the primer layer is prepared before the finish paint is prepared. Similarly, primer layers often cannot directly replace topcoats, and the paints used for primer layers are generally low in cost, poor in decorative effect, poor in apparent quality,

however, even the primer has a relatively weak affinity with metals due to its inherent property of paint, i.e., paint is a high molecular compound. Currently, in order to improve the adhesion between the primer and the metal substrate, there are two general ways, one is a pure mechanical treatment of the metal substrate to reduce the influence of interface impurities; the other is to perform chemical treatment on the basis of the first one. For the former, as in chinese patent document CN106824719A, it discloses a fluorocarbon embroidery paint coating process for steel, which only polishes and derusts a metal substrate, but does not change the metal property of the steel substrate, and even if polishing and derusting are limited, in practice, the mature process for treating a substrate needs to be deoiled, and pure mechanical polishing can not meet the process requirements of paint system preparation.

For the latter, i.e., chemical treatment, specifically, the metal substrate is subjected to chromizing to form a chromized film (otherwise referred to as a chromized layer). Chromizing is essentially a surface treatment process in which chromic acid or a chromate solution chemically reacts with a metal substrate and then a hexavalent or trivalent chromium layer is formed on the surface of the metal substrate. The aluminum and magnesium substrates can be directly chromized, and the iron substrate needs to be matched with phosphorization, but the overall understanding of the chromizing concept in the field is not influenced.

It is further noted that hexavalent chromium has relatively high corrosion resistance and durability, and trivalent chromium has relatively poor corrosion resistance and durability. However, the industrial use of hexavalent chromium has an inherent problem, hexavalent chromium is a swallowable and inhalant poison, and the list of toxic hazardous water pollutants (first lot) has been included in hexavalent chromium compounds at 23 months 7 in 2019. Thus, current industrial applications of chromizing are limited to trivalent chromium, but trivalent chromium has significantly insufficient performance in terms of corrosion resistance and durability relative to hexavalent chromium. Since hexavalent chromium has just been banned shortly, despite the long buffer periods that have been used before, there is still a major bottleneck to the performance improvement in industrial applications of trivalent chromium, and therefore, the performance improvement of paint systems based on trivalent chromium requires further research.

Typically, for example, chinese patent document CN104014471A discloses a fluorocarbon spraying method for aluminum alloy profile, which first cleans the aluminum material, then passivates in a passivation solution, and further cleans and chromizes after passivation. It is not indicated in this patent document whether chromising is hexavalent or trivalent and it is not fully disclosed which passivation is, indeed, a process for which chromising is also a passivation, but from a relative point of view the passivation used should not contain chromising. The passivation can effectively improve the adhesive force of a paint film, and can improve the corrosion resistance of a plating layer in the application of the plating layer. However, since chromizing is included in passivation, the common property is to form an oxide layer on the surface of the product by oxidation reaction, and chromizing after passivation, which is essentially conflicting, on the one hand, there is isolation of the passivation layer, for example, chromate cannot directly react with the metal substrate by oxidation-reduction reaction, and chromizing cannot proceed; on the other hand, assuming that chromate can react with the passivation layer, the role of the passivation layer is eliminated if the chromized layer partially displaces the passivation layer, and the probability of further oxidation of the metal oxide is very low, especially if the passivation layer is usually a steady state higher oxide. The use of the chromized layer in combination with the passivation layer is not supported by further data and is subject to further verification.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an adhesive force is higher imitative copper wire drawing board relatively between paint system and base plate.

In an embodiment of the utility model, a copper-like wire drawing plate is provided, including a metal substrate, and a chromizing layer, an interface layer, a primer layer, a copper-like finish paint layer, a wire drawing layer and a protective layer which are stacked on the metal substrate in sequence;

wherein the interface layer is a copper layer which is cold sprayed on the chromized layer, the thickness of the interface layer is 1.6-3.0 mu m, and the cold spraying material is copper powder with the average grain diameter of 1.5 mu m.

Optionally, the primer layer comprises two sub-layers, the sub-layer sprayed on the interface layer being a first sub-layer, which is sprayed on a second sub-layer after curing.

Optionally, the thickness of the first sub-layer is 2-3 μm;

the thickness of the second sub-layer is 7-14 μm.

Optionally, the primer layer is a fluorocarbon primer layer;

the wire drawing layer is a fluorocarbon black paint layer;

the protective layer is a fluorocarbon finishing paint layer;

wherein the thickness of the finish paint layer is 20-30 μm,

the thickness of the wire drawing layer is 7.5-10 mu m;

the thickness of the protective layer is 25 to 35 μm.

In the embodiment of the present invention, an extremely thin interface layer is sprayed on the outer surface of the chromizing layer, and the interface layer is formed by copper powder through a cold spraying process, and can have a very strong binding force with the chromizing layer. Because the interface layer is very thin, the uniformity control of the thickness of the interface layer is very difficult, the utility model discloses just use this characteristic of cold spraying, utilize the clearance between the copper powder granule to form the profile and combine. And the paint particles are far smaller than the copper powder particles, and the paint particles intervening in gaps among the copper powder particles are solidified to form anchoring points, so that the bonding firmness between the primer and the interface layer can be effectively improved. The weakest adhesive force of the paint system is the link between the primer and the metal substrate, the link adopts a chromizing layer in the traditional process for reinforcement, but is limited by the chromizing process, hexavalent chromium is not allowed to be used in the industry, and the interface layer is adapted under the condition of using trivalent chromium, so that the integral adhesive force of the paint system is improved, and the service life is longer.

Drawings

FIG. 1 is a schematic cross-sectional view of an exemplary copper-like wire drawing plate.

Fig. 2 is a photomicrograph (120 x) of a chromized layer coated with an interfacial layer, in which the relatively brighter portion is the clustered particles on the interfacial layer.

In the figure: 1. the wire drawing structure comprises a back paint layer, 2 a metal substrate, 3 a chromizing layer, 4 an interface layer, 5 a primer layer, 6 a finish paint layer, 7 a wire drawing layer and 8 a protective layer.

Detailed Description

The metal spraying process mainly comprises a cold spraying process and a hot spraying process, wherein the two processes have advantages and disadvantages, such as the hot spraying process, when metal or metal composite powder is sprayed, the oxidation, phase change and thermal decomposition of spraying particles are promoted at high temperature in the process of depositing the metal powder or metal composite powder on a substrate, the comprehensive performance of the coating is reduced, but the advantages are that the formed coating has higher bonding force with the substrate and is compact. In contrast, cold spraying accelerates a working gas through a laval tube, and the working gas entrains and accelerates metal particles, collides with the surface of a substrate, and plastically deforms to form a coating.

One of the main features of cold spraying over thermal spraying is that the cold spraying requires acceleration of the particles to a sufficiently high velocity, the temperature of the particles is not higher than their melting point, and since the substrate is usually a good conductor of heat such as iron, aluminum, etc., the particles are rapidly cooled after impact on the substrate, so that the maximum temperature of the coating and the attached substrate surface is usually below 150 ℃, and initially usually below 100 ℃, and the particles are not easily oxidized. Among them, regarding the speed, there is a critical speed Vcrit corresponding to the cold spray technology field, and when the particle is lower than the critical speed Vcrit, the particle is easy to fall off on the substrate, so in the coating preparation process, it is necessary to ensure that the particle is accelerated to above the critical speed Vcrit. For the critical speed Vcrit of cold spraying, reference is made to the document "critical speed of cold spraying and its influencing factors" ("material protection" volume 44, phase 4, 2011 month 4). Since the critical speed Vcrit is greater than or equal to 300m/s, and under most conditions, the critical speed Vcrit is greater than or equal to 500m/s and higher than the sound speed, the cold spraying is actually called supersonic cold spraying.

Although the adhesion of the coating prepared by cold spraying is lower than that of the coating prepared by hot spraying, the adhesion is still higher than that of a paint layer on the same substrate interface in a paint spraying process.

In addition, in the embodiment of the present invention, the final purpose of cold spraying is to deposit a thin layer of copper on the surface of the chromized layer 3, which is limited by the cold spraying process itself, when the prepared coating is thinner, the thickness uniformity of the coating will be worse, the gaps between the metal particles or the clustered metal particles attached to the base layer will be larger, and relatively speaking, the cold spraying will have a larger thickness, so as to obtain a tightly closed coating. In the embodiment of the present invention, the defect of the thinner cold spray coating is exactly reversed, that is, when the thickness of the copper coating is smaller, larger gaps between particles or clusters are inevitably formed, and tight sealing capability cannot be formed.

It is understood that the thickness of the coating produced by cold spraying is not much related to the magnitude of the adhesion, in other words, even if the thickness of the coating produced by cold spraying is small, the condition that the adhesion of the coating produced by cold spraying is high relative to that of the paint layer is still satisfied.

The paint system is described first below:

it should be noted that the first consideration of the copper-like bushing is the decorative characteristics and apparent quality of the decorative surface, as well as the useful life of the decorative surface. Generally, the decorative surface of the copper-like drawn plate generally has only one plate surface, which may be referred to as a front surface, and the surface opposite to the plate surface may be referred to as a back surface or a back surface. The back side is typically treated to preserve it, usually without regard to whether it has high decorative characteristics or good aesthetic qualities.

In addition, for example, if the chromizing layer 3 is used to immerse the whole metal substrate 2 into the chromizing tank, the surface of the metal substrate 2 is chromized on the whole, the chromizing layer 3 covers not only the front and back surfaces of the metal substrate 2 but also the side surfaces of the metal substrate 2, and based on the consideration of overall corrosion resistance, as shown in fig. 1, a back paint layer 1 exists, which belongs to the general in the art, in the embodiment of the present invention, the front paint layer is mainly explained, and the common knowledge of the paint layer on the other surfaces of the metal substrate 2 is not repeated.

The front side lacquer layer comprises in the structure shown in fig. 1a chromized layer 3, an interface layer 4, a primer layer 5, a top lacquer layer 6, a wire layer 7 and a protective layer 8. The paint system for the copper-like wire-drawing plate comprises the above-described chromized layer 3, primer layer 4, copper-like paint layer constituting the top coat layer 6, wire-drawing layer 7 which is typically a black or gray wire-drawing paint layer, and protective layer 8 which is typically a clear finish paint layer. In the embodiment of the present invention, an interface layer 4 formed based on a cold spray process is added to improve the adhesion of the paint system on the metal substrate 2.

Further, with respect to the interface layer 4, in the embodiment of the present invention, a copper layer is used, and the copper layer is sprayed on the chromizing layer 3 by a cold spraying process using copper powder having an average particle size of 1.5 μm.

As described above, cold spraying is performed under supersonic conditions, and copper powder is plastically deformed after impinging on chromized layer 3, so that plastic adhesion is generated between copper powder particles and is plastically adhered to chromized layer 3.

The copper powder is a powder material commonly used in a cold spraying process (other commonly used powder materials comprise aluminum powder, zinc powder, nickel powder, lead powder, tin powder and babbit alloy powder, wherein the nickel powder is more noble, the lead powder is not environment-friendly, the babbit alloy is relatively too soft, and the adhesive force between the aluminum powder, the zinc powder and the chromized layer does not meet the design requirement), and the bonding force between the copper powder and the chromized layer 3 serving as a cold spraying substrate is stronger.

In addition, because copper belongs to oxidation-sensitive materials, the working gas selected during spraying is inert gas. Proved by verification, when the working gas is 500 ℃, copper is not easy to oxidize under the wrapping of the working gas, has certain plasticity and is easy to adhere to the chromizing layer 3. As mentioned above, the prepared interface layer 4 is relatively thin, preferably 1.6-3.0 μm, and belongs to the primary stage of conventional cold spraying, the cold spraying matrix as the chromized layer 3+ metal substrate 2 has not been heated too much, the temperature of the spraying matrix is not higher than 100 ℃, and under the condition, copper is not easily oxidized in a short time.

Helium is preferred as the working gas, the density of the coating formed by helium spraying is higher than that of the coating formed by nitrogen or argon spraying, and the dynamic compression strength of the nitrogen spraying coating is higher than that of the nitrogen or argon spraying coating under the same conditions.

The thickness of the interface layer 4 is an average thickness of the interface layer 4, and is understood to correspond to approximately two times of the laval torch sweep. The apparent color of the sprayed paint is greenish by visual observation, if the sprayed paint is too thick, the green color is gradually covered by yellow, and if the sprayed paint is less, the color is silvery white and bluish. During specific operation, the Laval spray gun can be erected on the linear guide rail, and the target position is swept twice back and forth at the speed of 0.3m/s, so that the apparent color is silvery white and greenish.

In the microscopic condition shown in fig. 2, the interface layer 4 with relatively high brightness in the figure does not completely cover the chromizing layer 3 with relatively low brightness due to the smaller spraying amount, and the interface layer 4 has larger gaps.

The paint particles in the paint mist are of a smaller size relative to the gap, and can be inserted into the gap to form an anchoring point after curing.

In the embodiment of the present invention, after the copper interface layer 4 is formed by cold spraying, no other strengthening treatment is performed, and then the primer layer 5 is prepared on the interface layer 4 by spraying.

In order to verify the adhesion of the primer layer 5, 10 test pieces (10 test pieces for each experiment) were tested according to the test method specified in GB/T5237.5-2017 (fifth part of aluminium alloy building section: painted section), the test results being:

film thickness, not detected;

gloss, no detection;

color difference, not detected;

hardness, not tested;

the dry adhesive force, the wet adhesive force and the boiling water adhesive force of 10 test pieces reach 0 level;

10 test pieces have no foaming and no obvious change in surface dryness in hydrochloric acid resistant experiments;

nitric acid resistance, not detected;

the 10 test pieces are detected to have no cracking or falling phenomenon;

10 test pieces are detected to be resistant to washing, and no bubbling, dropping and other obvious appearance phenomena exist.

Solvent resistance was not detected;

the 10 test pieces are subjected to mortar resistance detection, and have no shedding or other obvious phenomena;

the damp-heat resistance test shows that 3 of 10 test pieces have no foaming, falling and other obvious phenomena within 1200h, 1 test piece has no foaming, falling and other obvious phenomena within 1100h, and 6 test pieces have no foaming, falling and other obvious phenomena within 1300 h;

salt spray corrosion resistance, no detection;

no detection in AASS experiment;

the weather resistance was not examined.

After the interface layer 4 is provided, the primer layer 5 has relatively good adhesion capability, and has higher requirements on moisture and heat resistance when used as a copper-like wire drawing plate of a decorative plate, when the interface layer 4 is not provided, the primer layer mostly generates a shedding phenomenon for more than 900 hours, the primer layer is extremely little for more than 1000 hours, and after the interface layer 4 is provided, the primer layer 5 has better adhesion force.

The inventor tries the overheating spraying, the spraying matrix is usually subjected to sand blasting treatment in advance, the chromizing layer 3 is damaged to a certain extent, the adhesion of the chromizing layer 3 is possibly insufficient, and the paint system has a short adhesion plate, so that the adhesion of the whole paint system is weakened.

As can be seen from the foregoing, the topcoat layer 6 is primarily concerned with the apparent mass and decorative effect, and the topcoat layer 6 is typically relatively small in thickness, which thickness generally requires that its color be sufficient to mask the color of the primer layer 5 and sufficiently express its own color.

The apparent mass of primer layer 5 also has an effect on topcoat layer 6, in contrast, since paints typically incorporate a certain amount of solvent or diluent that evaporates and adheres to and remains on the substrate, which would cause the thickness of the paint layer to vary, and if primer layer 5 were uneven, topcoat layer 5 would also be uneven.

One function of the primer layer 5 is leveling, and for a conventional substrate, the conventional substrate often has good surface flatness and has low requirement on the leveling function of the primer layer 5. In the embodiment of the present invention, because the interface layer 4 exists, it has a larger porosity, and the interface layer 4 needs to be leveled relative to the chromized layer 3.

In the embodiment of the present invention, the primer layer 5 has two sub-layers, a first sub-layer is formed by spraying on the interface layer, and a second sub-layer is formed by spraying after the first sub-layer is cured. Because the existence of interface layer 4, relative to the paint system of the same kind, priming paint layer 5 needs the thickness of relatively bigger, in the embodiment of the utility model, can consult ground and increase priming paint layer 5 thickness to 1.1 times of priming paint layer 5 thickness when not having interface layer 4, can possess roughly the same apparent mass. When a two sublayer structure is employed, the thickness of the primer layer 5 may be approximately comparable to the primer layer thickness without the interface layer 4, while the apparent mass is substantially the same.

The paint and the diluent are in a liquid state in a matching manner, and based on the fluidity during spraying, the influence of shrinkage on the place where a gap exists on the interface layer 4 can be effectively compensated, and the apparent mass of the first sublayer is different from that of the paint when the first sublayer is dried or cured.

Further, spraying the second sub-layer after the first sub-layer is cured can reduce the effect of shrinkage on the apparent quality, and thus a relatively thin primer layer 5 can still be provided in the presence of the interface layer 4.

The first sub-layer is mainly used to fill the gap on the interface layer 4, and the thickness of the first sub-layer is relatively small, and is selected to be 2-3 μm in the embodiment of the present invention. The two sub-layers are combined to form the primer layer 5, and the second sub-layer determines the total thickness of the primer layer 5, and is selected to be 7-14 μm in the embodiment of the present invention. The total thickness of the primer layer 5 is selected differently according to the metal substrate 2 and the selection of the primer, which is common knowledge in the art and is not a modification of the present invention, and will not be described herein again.

It should be noted that the thicker the paint system, the more brittle it is known to be, and therefore, the structural layers in the paint system should be as thin as possible under the condition of satisfying the basic technical requirements.

Regarding the service life of the paint system, in addition to the paint system preparation process and the paint system structure, it is also the service life of the paint itself that affects its service life. The service life of paint generally used as decoration is about 10 years. With the development of paint technology, fluorocarbon paints having a longer service life are also being gradually applied to decorative panels.

The utility model discloses an in the embodiment, choose for use the fluorocarbon lacquer series for spraying that the garden fonder nation fluorocarbon science and technology limited company produced, compare in ordinary paint, the fluorocarbon lacquer has longer life, under the same service condition, the fluorocarbon lacquer can have ordinary decoration with the life about the paint twice.

Preferably, the primer layer 5 is a fluorocarbon primer layer, and is made of a fluorocarbon primer produced by Weifang Pongda fluorocarbon technology limited company.

The wire drawing layer 7 is a fluorocarbon black paint layer, and is made of black fluorocarbon paint produced by Weifang Pondo fluorocarbon technology limited company.

The protective layer 8 is a fluorocarbon finishing paint layer, and is made of a fluorocarbon finishing paint produced by Weifang Pondong fluorocarbon technology Limited.

Wherein the thickness of the finish paint layer 6 is 20-30 μm.

The thickness of the wire drawing layer 7 is 7.5 to 10 μm.

The thickness of the protective layer 8 is 25 to 35 μm.

In addition to the aforementioned thickness parameters, the thicknesses of the topcoat layer 6, the wiredrawing layer 7, and the protective layer 8 may be selected by those skilled in the art according to different objects to be used.

It can be understood that the fluorocarbon paint is mature, the fluorocarbon paint used in the embodiment of the present invention does not limit the scope of the claims, and similar fluorocarbon paints can be tried to be used in the decorative board.

Copper powder is preferred, electrolytic copper powder having a high purity, typically greater than 99.9%, and in some embodiments copper powder having a purity of 99.5% may also be used. The higher the purity and the finer the granularity of the copper powder, the higher the price of the copper powder, and the price of the copper powder belongs to the market price, which is not described in detail herein.

In the embodiment of the utility model, the copper powder is selected with the average grain diameter of 1.5 μm, which belongs toThe superfine copper powder in the powder classification has moderate price and specific surface area of 0.5-4.0 m²(g) the apparent density is 0.5-2 g/cm³The loose state will be different. The powder material has a relatively large specific surface area and is suitable for feeding powder by using working gas. The particle diameter of the copper powder is plastically deformed after the copper powder particles impact the surface of the base material, and the copper powder particles are roughly flaky, and plastic bonding occurs between flaky particles as the copper powder is gathered, thereby forming a structure as shown in fig. 2.

The following describes in detail the manufacturing process of the wire-drawing imitation copper plate by using an aluminum plate as a metal substrate 2:

the overall preparation scheme is represented as: aluminum plate → pretreatment → upper rack → soot blowing → sanding residue (fine sand paper) → fluorocarbon primer → top coat → baking → wire drawing ash → wire drawing → finish coating → baking → coating film.

The method comprises the following steps of firstly, preprocessing, wherein the preprocessing mainly comprises cleaning, chromizing and cold spraying.

Wherein, then including mechanical clearance and chemical clearance to the clearance, to mechanical clearance, if the aluminum plate situation is better, can not carry out mechanical clearance. If the mechanical cleaning is rust removal, if the surface of the aluminum plate is not rusted, the rust removal treatment can not be carried out.

The current plates used as decorative plates are mainly of two types, one type is an aluminum-based plate, the other type is a pure aluminum plate and an aluminum alloy plate, the other type is an iron-based plate, the iron-based plate is mainly an iron-carbon alloy plate, belongs to steel in iron-carbon alloy, and compared with the aluminum-based plate, the iron-based plate is easier to rust, and the iron-based plate generally needs a mechanical rust removal step.

More specifically, before the copper wire drawing imitation spraying, the surface of a workpiece, such as the surface of an aluminum plate, needs to be subjected to chemical treatment for removing oil stains, and then chromized, so that the adhesion between the coating and the surface of the aluminum plate and the oxidation resistance are increased, and the service life of a paint film is prolonged. In order to further improve the adhesion capability of the paint system, a cold spraying layer is manufactured outside the chromizing layer.

The aluminum material is firstly degreased and decontaminated, and is firstly washed by water, the aluminum material is roughly washed by water which can be tap water at the initial stage, and after the rough washing is finished, the aluminum plate is sent into an alkali tank for alkali washing, wherein the purpose of the alkali washing is to remove oil stains on the surface of the aluminum plate, remove an oxide film on the surface of the aluminum plate and eliminate the slight defect on the surface of the aluminum plate.

The alkali washing adopts sodium hydroxide solution to carry out alkali washing, and the embodiment of the utility model adopts a mode of adding 45g of sodium hydroxide into one liter of water to prepare the sodium hydroxide solution. The temperature of the sodium hydroxide solution is 55 ℃, the temperature fluctuation range is controlled within 5 ℃, and the cleaning time is 50 seconds. The alkaline washing mode is mainly used for higher-grade products.

In some embodiments, a relatively high concentration of alkali solution may be used, for example, if 100-160 g of sodium hydroxide is added in one liter of water, and a certain amount of sodium nitrate is added, the amount of sodium nitrate may be 300-350 g, the temperature of the alkali solution is controlled to 85 ℃, and the temperature fluctuation range is controlled to be within 5 ℃. The cleaning time is selected according to the surface quality of the workpiece, the aluminum plate with better surface quality can be cleaned for 30 seconds generally, and the aluminum plate with slightly scratched surface can be cleaned for a longer time to eliminate slightly scratched marks, but the cleaning time is not longer than 150 seconds. The high-concentration alkali liquor can effectively eliminate the mechanical defects on the surface of the aluminum plate.

In some embodiments, it is also possible to use a higher concentration of lye for washing, with 250g or more of sodium hydroxide being added to one liter of water, and a small amount of sodium nitrate, if 80g is preferred. In this embodiment primarily for creating a silvery white appearance.

After the alkaline washing is finished, clear water is used for washing away alkaline liquor remaining on the surface of the aluminum plate, then acid washing is carried out, and due to the fact that dirt and slight mechanical defects on the aluminum plate are removed through the alkaline washing, on one hand, the dirt is further removed through the acid washing, and on the other hand, remaining trace alkaline liquor components are washed away through the acid washing.

The pickling method comprises the specific steps of firstly, putting an aluminum plate into dilute nitric acid with the mass percentage of 5-7% for pickling for 30-50 seconds; then the aluminum plate is taken out and put into a cold water tank for washing, and then the aluminum plate is washed by warm water. When the aluminum alloy plate is washed by warm water, the water temperature is not required to be too high and is controlled below 40 ℃, otherwise, the aluminum alloy plate is easy to age.

Before chromizing, the aluminum plate needs to be washed by deionized water or pure water.

Chromizing: chromising chromating is carried out with a chromate to form trivalent chromium. If the iron-based plate is chromized, phosphoric acid is required to be added into the chromizing liquid, and the adding amount of the phosphoric acid is 1-2 g per liter of water.

The chromizing is a conventional process in the art and will not be described in detail.

Forming a chromizing layer 3 after chromizing, and further forming an interface layer 4 on the chromizing layer 3 by adopting a cold spraying process. Before cold spraying, the aluminum plate needs to be cleaned, cleaned by common water, cleaned by pure water or deionized water, and dried.

After air drying, copper powder with the average particle size of 1.5 mu m is sprayed on the chromizing layer 3 by adopting a cold spraying process to form an interface layer 4 with the thickness of 1.6-3.0 mu m; the spraying process parameters are as follows: the spraying speed is 580-620 m/s, the powder feeding pressure of the working gas is 1.5-2.5 MPa, and the temperature of the working gas is 500-560 ℃.

The formation of the interface layer 4 is followed by the application of a primer layer 5, the paint being applied by spraying in a manner consistent with the specifications of GB/T5237.5-2017 (fifth part of aluminium alloy building section: sprayed section), the properties of the relevant paint layer being able to be checked according to this recommended standard.

And after the primer layer 5 is cured, finishing paint can be sprayed, wherein the finishing paint is one of two functional layers for obtaining the final apparent effect, and the finishing paint is prepared on the primer layer 5 by adopting a copper-like finishing paint in a spraying mode to form a finishing paint layer 6.

It can be understood that the finish paint needs to be sprayed with a suitable diluent, generally speaking, a fixed ratio (generally about 5%, if air spraying is adopted, about 10% is needed, the percentage is volume percentage, and the diluent occupies volume percentage of the finish paint) is adopted between the finish paint and the diluent, the diluent adopts a special diluent for fluorocarbon finish paint, and the main components are benzene, dibutyl ketone and butyl acetate.

In the embodiment of the present invention, the amount of the diluent is adjusted according to the ambient temperature, and particularly, the amount of the diluent is increased along with the increase of the ambient temperature.

If a common spraying mode is adopted, 0.05 liter of diluent is added into 1 liter of finish paint when the ambient temperature is 10-20 ℃, 0.055 liter of diluent is added into 1 liter of finish paint when the ambient temperature is 20-30 ℃, and 0.06 liter of diluent is added into 1 liter of finish paint when the ambient temperature is more than 30 ℃.

After the finishing paint layer 6 is fully dried, the wire drawing process layer is sprayed on the finishing paint layer 6, the drying of the finishing paint layer 6 is usually carried out by directly sending the finishing paint layer into an oven for baking after the spraying is finished, and researches show that the swelling is easily generated on the finishing paint layer due to the thinner and the evaporation of the moisture during the direct drying because the finishing paint layer 6 contains the thinner and the unavoidable moisture.

In the embodiment of the utility model, after finishing the finish coat layer 6, it is air-dried to put it to ventilate department now, send into the baker after the surface is dry and toast, toasts the condition and toasts 10~15min under the 220 ℃ condition.

And after the finish paint layer 5 is fully dried, spraying the wire drawing process layer on the surface of the finish paint layer, and further curing the wire drawing process layer. Because the wire drawing process layer is thin, after the spraying is finished, a batch of workpieces are sent into a baking oven to be baked, the baking temperature is 220 ℃, and the baking time is 5 min.

The scouring pad is used as a tool to rub and draw wires back and forth on the wire drawing process layer in a fixed direction, the scouring pad is generally fixed on a plate-shaped part, the scouring pad is in contact with the wire drawing process layer surface on a workpiece, and the pressure of 100-300 Pa is applied to the plate-shaped part.

The higher the pressure intensity is, the higher the wire drawing efficiency is, the more the paint amount ground off in each wire drawing stroke is, and the worse the precision control is, therefore, the wire drawing condition can be observed in real time during wire drawing.

In some embodiments, variable pressure drawing may also be employed, with higher draw pressure at the early stage, and the pressure is gradually reduced during drawing.

The drawing effect is generally provided by a client side, and drawing can be compared with the sample plate in the early stage drawing.

In addition, regarding the wire drawing process layer, samples are generally required to be reserved, generally, the number of the reserved samples is not less than 3, the color of the workpiece with the samples is required to be compared, and the target of the color comparison is the gray level of the template.

Whether the color of the wire drawing process layer is proper or not can be judged by visual observation generally, and a gray scale meter can be used for detection in some embodiments.

In some embodiments, the reserved workpiece and the template can be arranged side by side without depending on a special instrument and adopting other gray scale comparison modes, then a picture is taken, and color channel values are extracted by using Photoshop, so that accurate comparison can be carried out.

For the wiredrawing layer 7 formed after wiredrawing, whether the wiredrawing effect meets the requirement or not is generally determined through manual comparison, and 3-4 samples are usually reserved on the workpiece after the wiredrawing layer 7 is prepared.

Cleaning treatment is carried out after wire drawing, then finishing paint is sprayed to form a protective layer 8, the finishing paint is transparent paint, the final visual effect of the wire drawing can still be influenced to a certain extent, and certain glossiness can be generated besides the striped plate effect of the wire drawing.

Similarly, 3-4 pieces may be left after spraying the finishing paint and final curing.

Further, with regard to drawing, the depth of the draw will determine the visual effect of the draw plate, and typically requires recalibration after changing the scouring pad.

The drawing is generally dry drawing, and particularly, the current drawing mainly adopts acrylic drawing and needs to be matched with pure water. In the embodiment of the utility model, adopt ordinary water to carry out the wire drawing, can use water as grinding fluid, in some embodiments, the wire drawing can be gone on in the basin.

The uniformity of water wire drawing is better, if carry out the wire drawing in the basin, because the existence of water, at the wire drawing in-process, the motion of scouring pad can arouse rivers, can in time clear away the lacquer bits that pull off, can not produce additional interface abrasive material, and the apparent effect of wire drawing out is relatively even.

After wire drawing, the dirt on the wire drawing layer 7 is cleaned by water in time, and then water is sucked by a water absorption material, and the water is sucked by cotton cloth or other hydrophilic materials, so that water scale is prevented from being left after common water is dried.

And after the wire drawing layer 7 is dried, spraying finishing paint.

The finishing paint needs to be baked and cured after being sprayed, the curing temperature is 220 ℃, and the curing time is 10-15 minutes.

Regarding the thickness of the finishing paint layer, i.e. the protective layer 8, if it is too thin, the brightness is not good, the protective layer 8 is generally controlled at 50 μm, and in some embodiments, the protective layer 8 below 20 μm may also be used, the key being the actual requirement of the customer for the glossiness.

It can be understood that, for the drawn imitation copper plate, stripe drawing is generally adopted, generally vertical stripe or horizontal stripe (in the use state of the decorative plate), and in the actual demand, the demand for the random stripe is also existed, and the drawing process mainly aims at the specific parameters of the drawing process adapted to the template provided by the customer.

Therefore, the effect of the present invention is described in the embodiment of the present invention by way of example, but the scope of protection of the present invention is not limited to the embodiment of the present invention, and basically the same means is adopted and basically the same effect is achieved based on the same concept, and the present invention is also within the scope of protection of the present invention.

Claims (4)

1. The copper-imitated wiredrawing plate is characterized by comprising a metal substrate, and a chromizing layer, an interface layer, a primer layer, a copper-imitated finish paint layer, a wiredrawing layer and a protective layer which are sequentially stacked on the metal substrate;

wherein the interface layer is a copper layer which is cold sprayed on the chromized layer, the thickness of the interface layer is 1.6-3.0 mu m, and the cold spraying material is copper powder with the average grain diameter of 1.5 mu m.

2. The copper-like wire drawing plate according to claim 1, wherein the primer layer comprises two sub-layers, and the sub-layer sprayed on the interface layer is a first sub-layer, and the first sub-layer is sprayed with a second sub-layer after being cured.

3. The copper-like wire drawing plate according to claim 2, wherein the first sub-layer has a thickness of 2 to 3 μm;

the thickness of the second sub-layer is 7-14 μm.

4. The copper-like wire drawing plate according to claim 1, wherein the primer layer is a fluorocarbon primer layer;

the wire drawing layer is a fluorocarbon black paint layer;

the protective layer is a fluorocarbon finishing paint layer;

wherein the thickness of the finish paint layer is 20-30 μm,

the thickness of the wire drawing layer is 7.5-10 mu m;

the thickness of the protective layer is 25 to 35 μm.

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