CN111793394A

CN111793394A - Agent for stabilizing rust layer on surface of weathering resistant steel and method for coating film on surface of weathering resistant steel

Info

Publication number: CN111793394A
Application number: CN202010666089.0A
Authority: CN
Inventors: 王胜荣; 杨建炜; 曹建平; 高立军
Original assignee: Shougang Corp
Current assignee: BEIJING SHOUGANG HUAXIA ENGINEERING TECHNOLOGY CO LTD; Shougang Group Co Ltd
Priority date: 2020-07-12
Filing date: 2020-07-12
Publication date: 2020-10-20
Anticipated expiration: 2040-07-12
Also published as: CN111793394B

Abstract

The invention discloses a weathering steel surface rust layer stabilizing treatment agent and a weathering steel surface coating treatment method, wherein the treatment agent comprises the following components in parts by weight: film forming agent: 50-80 parts; an inducer: 1-10 parts; phosphating agent: 0.2-1 part; accelerator (b): 1-5 parts; modifying agent: 1-10 parts; corrosion inhibitor: 1-10 parts; surface auxiliary agent: 0.05-0.3 part; wetting and dispersing agent: 0.05-0.4 part; leveling agent: 0.05 to 0.4 portion. When the weathering steel subjected to surface coating treatment by the treating agent disclosed by the invention is used in a marine atmospheric environment, a compact and stable rust layer can be quickly formed, the forming period is shortened to 1-2 years, the resistance is 100 times that of bare steel, the corrosion resistance is good, and the environmental pollution problems of rust liquid sagging, flying and the like are prevented.

Description

Agent for stabilizing rust layer on surface of weathering resistant steel and method for coating film on surface of weathering resistant steel

Technical Field

The invention belongs to the technical field of corrosion of steel materials, and particularly relates to a weathering steel surface rust layer stabilizing treatment agent and a weathering steel surface coating treatment method.

Background

The weathering steel surface rust layer stabilizing treatment agent is a coating product for promoting the weathering steel surface to form a stable rust layer and improving the corrosion resistance of the weathering steel. The weathering steel is alloyed by adding corrosion resistant elements such as Cu, P and the like, so that a metal material is promoted to generate a compact corrosion product protective film in a corrosion system, thereby reducing the corrosion speed and enhancing the corrosion resistance of the material. In industrial atmospheric environments, the weather-resistant steel has a significant advantage in terms of atmospheric corrosion resistance over carbon steel, because a dense rust layer is formed on the surface of the weather-resistant steel, which prevents the entry of corrosive media. The rust layer formed on the surface of the carbon steel is loose and has a large number of microcracks and cavities, so that the surface metal cannot be protected. Although weathering steel has good corrosion resistance, it has been found that it takes more than 3 years to achieve stabilization of the rust layer in the natural environment. Before a stabilized rust layer is formed, the phenomena of early rust liquid sagging and flying are often generated, which not only pollutes the surrounding environment, but also is difficult to realize the significance of the weathering steel. Therefore, the research on the stabilization treatment of the rust layer on the surface of the weathering steel is started, and the surface of the weathering steel component is pretreated before use so as to accelerate the formation of the stable and compact rust layer on the surface and reduce or even eliminate the environmental pollution problems of rust liquid sagging, flying and the like in the formation process of the protective rust layer.

At present, some work is carried out on the surface stabilization treatment technology of the weathering steel in China, but the mature technology for stabilizing the rust layer on the surface of the weathering steel component widely applied to the marine atmospheric environment is not developed yet. Because the flying amount of sea salt particles exceeds 0.05mdd (mdd is mgNaCl/dm) especially in the marine atmospheric environment²Abbreviation of day) air contentPoly (Cl)^-The conventional weathering steel surface treatment technology is difficult to form a compact rust layer, and the weathering steel cannot be used in a naked state in the environment and needs to be coated for use.

Disclosure of Invention

The invention provides a stabilizing agent for rust layer on the surface of weathering steel and a method for coating film on the surface of weathering steel, aiming at solving the problem of high Cl content^-In the marine atmospheric environment, the weathering steel is difficult to quickly form a compact rust layer, and the rust liquid is sagging and flying.

On the one hand, the weathering steel surface rust layer stabilizing treatment agent comprises the following components in parts by weight:

film forming agent: 50-80 parts;

an inducer: 1-10 parts;

phosphating agent: 0.2-1 part;

accelerator (b): 1-5 parts;

modifying agent: 1-10 parts;

corrosion inhibitor: 1-10 parts;

surface auxiliary agent: 0.05-0.3 part;

wetting and dispersing agent: 0.05-0.4 part;

leveling agent: 0.05 to 0.4 portion.

Further, the film forming agent is any one of the following: polyvinyl butyral resin, and aqueous acrylic resin.

Further, the inducer is any one or more of the following: FeO, Fe₂O₃、Fe₃O₄。

Further, the phosphating agent is any one of the following components: phosphoric acid, phosphates;

further, the accelerator is any one or more of the following: chromium sulfate, nickel sulfate.

Further, the modifier is any one or more of the following: cr (chromium) component₂O₃、CaO、Al₂O₃、ZrO。

Further, the particle size of the modifier is 100 nm-50 μm.

Further, the treating agent also comprises 500-800 parts of ethanol by weight.

In another aspect, the present invention provides a weathering steel surface coating treatment method, which uses the above weathering steel surface rust layer stabilizing agent to perform coating treatment, the method comprising,

mixing and stirring the raw materials and ethanol, and dispersing to obtain a treating agent; the raw materials comprise the following components in parts by weight: film forming agent: 50-80 parts; 1-10 parts of an inducer; phosphating agent: 0.2-1 part; the accelerator comprises: 1-5 parts; 1-10 parts of a modifier; corrosion inhibitor: 1-10 parts; surface auxiliary agent: 0.05-0.3 part; wetting and dispersing agent: 0.05-0.4 part; leveling agent: 0.05-0.4 part;

and (3) coating the treating agent on weathering steel to finish coating treatment.

Further, the surface roughness of the weathering steel is 2.50-3.50 μm.

Further, the thickness of the coating film is 20-40 μm.

One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

the embodiment of the invention provides a weathering steel surface rust layer stabilizing treatment agent and a weathering steel surface coating treatment method, wherein the treatment agent comprises the following components in parts by weight: film forming agent: 50-80 parts; an inducer: 1-10 parts; phosphating agent: 0.2-1 part; accelerator (b): 1-5 parts; modifying agent: 1-10 parts; corrosion inhibitor: 1-10 parts; surface auxiliary agent: 0.05-0.3 part; wetting and dispersing agent: 0.05-0.4 part; leveling agent: 0.05 to 0.4 portion. This application has formed fine and close protection film through the ratio of control raw materials, and this layer of protection film can prevent the Cl-entering in the ocean atmosphere, allows air and water to get into, can accelerate the formation of stable rust layer simultaneously, and the formation time of stable rust layer can shorten to 1 ~ 2 years, and the impedance is 100 times of bare steel, and corrosion resistance is good, has avoided environmental pollution problems such as rust liquid sagging, fly apart in the formation of protective rust layer.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

FIG. 1 is a macroscopic view of weathering steel subjected to circumferential immersion for 0 day after the coating treatment of the embodiment of the present invention;

FIG. 2 is a macro morphology of weathering steel subjected to circumferential immersion for 28 days after the coating treatment of the embodiment of the present invention;

FIG. 3 is a macro morphology of weathering steel subjected to circumferential immersion for 56 days after the coating treatment of the embodiment of the present invention;

FIG. 4 shows the impedance change of the bare steel and the coated sample of the embodiment of the invention after different immersion experiments;

FIG. 5 shows the impedance change of the bare steel and the coated film sample of the embodiment of the invention after different immersion experiments.

Fig. 1 to 3 illustrate: white point objects are distributed on the weathering steel with the macroscopic appearance of iron red after the weathering steel is soaked in the surrounding of the coating treatment, the iron red corresponds to black in figures 1 to 3, and the white point objects correspond to white point objects in figures 1 to 3.

Detailed Description

The present invention will be described in detail below with reference to specific embodiments and examples, and the advantages and various effects of the present invention will be more clearly apparent therefrom. It will be understood by those skilled in the art that these specific embodiments and examples are for the purpose of illustrating the invention and are not to be construed as limiting the invention.

Throughout the specification, unless otherwise specifically noted, terms used herein should be understood as having meanings as commonly used in the art. Accordingly, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. If there is a conflict, the present specification will control.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.

In order to solve the technical problems, the embodiment of the invention provides the following general ideas:

in a first aspect, an embodiment of the invention provides a weathering steel surface rust layer stabilizing treatment agent, which comprises the following components in parts by weight:

film forming agent: 50-80 parts;

1-10 parts of an inducer;

phosphating agent: 0.2-1 part; the phosphating agent is any one of the following components: phosphoric acid, phosphates;

accelerator (b): 1-5 parts;

1-10 parts of a modifier;

corrosion inhibitor: 1-10 parts;

surface auxiliary agent: 0.05-0.3 part;

wetting and dispersing agent: 0.05-0.4 part;

leveling agent: 0.05 to 0.4 portion.

In this application, the film forming agent is the main raw material, plays the effect of fixing other raw materials to the weathering steel surface. At the same time, the film-forming agent allows water and air to pass through so as to react to form a stable rust layer, and on the other hand, can make the coating film formed by the coating film treatment compact and prevent Cl^-To enter. The film forming agent is too high in weight part to form a complete coating film; the weight portion of the film forming agent is too low, and the filler cannot be completely fixed after the coating film is cured.

In the present application, iron oxide, such as Fe, is added to the inducer in appropriate amounts₂O₃、Fe₃O₄And the rust inhibitor can be used as a nucleation point to induce a rust layer transformation process, or can shorten the rust layer stabilization period and accelerate the formation of stable and well-protected alpha-FeOH of a rust layer. The proportion of the initiator is too high, the cost is increased, and the film is not easy to form; the proportion of initiator is too low to form a stabilized rust layer.

The phosphating agent can provide phosphate radical to form a metal non-conductive iron phosphide protective film and reduce electrochemical reaction; the adhesion between the weatherable steel substrate and the coating can also be improved. The proportion of the phosphating agent is too large, so that the excessive phosphate ions influence the balance of iron phosphate film forming and easily cause too high acid value of a system; the proportion of the phosphating agent is too low, so that an iron phosphate protective film is not easy to form.

The accelerator generally adopts a proper amount of chromium salt or nickel salt, the chromium can promote the weathering steel rust layer to be converted into a stable state from an initial unstable state along with the corrosion, the corrosion resistance is enhanced, and simultaneously, the chromium can promote alpha-FeOOH and alpha- (Fe) in the rust layer_1-xCr_x) And due to the generation of OOH, the rust layer is more stable and compact, and the blocking capability of the rust layer to the transmission process of a corrosive medium is improved. The addition of nickel can promote Fe in the rust layer₂NiO₄And forming an equi-nano-scale network structure, thereby improving the corrosion resistance of the rust layer. The accelerant has an overlarge proportion, wherein the chromium salt belongs to heavy metal salt, so that the environmental pollution is caused, the chromium salt is not easy to be added too much, and the cost is increased; if the accelerator ratio is too small, the formation of a rust layer cannot be promoted.

The modifier is mainly used for repairing the defects of pores, cracks and the like in the coating film and blocking the passage of external corrosive media. The film forming property of a coating film is influenced due to the overlarge proportion of the modifier, and solid particles are easy to agglomerate and are not easy to disperse in a film forming reagent; the proportion of the modifier is too small, and the defects of pores and the like in the coating film cannot be completely repaired.

The corrosion inhibitor may chemically react with the metal surface to form a passivation product, thereby blocking Cl^-And entering to prevent the metal surface from further generating rust. The proportion of the corrosion inhibitor is too large, so that the cost is increased and waste is caused; the corrosion inhibitor has too small a proportion to have the effect of slowing down the corrosion. Corrosion inhibitors in this application include, but are not limited to, any one or more of the following: molybdate, nitrite, phosphate, phytic acid and tannic acid.

The surface auxiliary acts to significantly reduce the surface tension of the coating system, thereby improving substrate wetting and preventing cratering. Can increase surface smoothness and improve luster. Too large a proportion of surface auxiliaries increases the cost and at the same time is less compatible with other auxiliaries in the system. The ratio is too low to reduce the surface tension. Surface aids herein include, but are not limited to, any of the following: BYK-310, BYK-378.

The wetting dispersant functions to deflocculate the pigment by steric hindrance. Because the deflocculated pigment particles are small, high gloss and improved color strength can be achieved. In addition, transparency and hiding power are increased. The auxiliaries reduce the viscosity, thus improving the levelling and increasing the pigment addition. Too large a proportion of wetting dispersant will increase the viscosity of the system and the effect will be limited. If the ratio is too low, the pigment and filler cannot be fully wetted, and the filler cannot be uniformly dispersed. Wetting dispersants herein include, but are not limited to, any of the following: BYK-101, BYK-130, BYK-160 and BYK-9076.

The leveling agent functions as an aid to prevent cratering and improve leveling. It can improve the gloss and long-wave leveling effect of the coating. It only slightly reduces the surface tension and does not affect the recoating and interlayer adhesion. Too large a proportion of levelling agent will increase the viscosity of the system and the effect will be limited. If the ratio is too low, the defects of leveling and shrinkage cannot be improved. Leveling agents herein include, but are not limited to, any of the following: BYK-300, BYK-306 and BYK-316N, BYK-361.

Further, the film forming agent is any one of the following: polyvinyl butyral resin, and aqueous acrylic resin. The film forming agent has certain sealing property after film forming, allows water and air to enter, and can react with the filler in the coating film.

Further, the inducer is any one of the following substances: FeO, Fe₂O₃、Fe₃O₄。

further, the accelerator is any one of the following: chromium sulfate, nickel sulfate.

Further, the modifier is any one of the following: cr (chromium) component₂O₃、CaO、Al₂O₃ZrO, the particle size of the modifier is 100 nm-50 mu m

The modifier has too large particle size to fill the defects of coating film pores and the like, and has too small particle size, so that the modifier is not easy to disperse uniformly in a film forming solvent and is easy to agglomerate.

Further, the treating agent also comprises 500-800 parts of ethanol by weight.

Ethanol is the solvent in this application.

In a second aspect, the embodiment of the invention provides a weathering steel surface coating film treatment method, which uses the above weathering steel surface rust layer stabilizing treatment agent to perform coating film treatment, and comprises,

s1, mixing and stirring the raw materials and ethanol, and dispersing to obtain a treating agent; the raw materials comprise the following components in parts by weight: film forming agent: 50-80 parts; 1-10 parts of an inducer; phosphating agent: 0.2-1 part; accelerator (b): 1-5 parts; 1-10 parts of a modifier; corrosion inhibitor: 1-10 parts; surface auxiliary agent: 0.05-0.3 part; wetting and dispersing agent: 0.05-0.4 part; leveling agent: 0.05 to 0.4 portion.

In actual operation, in order to mix the raw materials more uniformly, the film forming agent can be mixed with absolute ethyl alcohol, the mixed solution is heated to 30-40 ℃, and the mixed solution is stirred for 1 hour at the rotating speed of 1000-1500 r/min, so that the film forming agent is completely dissolved in the absolute ethyl alcohol.

Adding a film forming reagent agent completely dissolved in ethanol into a high-speed dispersion machine, adding an inducer, a phosphating agent, an accelerator, a modifier, a corrosion inhibitor, a surface auxiliary agent, a wetting dispersant and a flatting agent into the high-speed dispersion machine according to the mixture ratio, stirring at the rotating speed of 5000r/min while adding, and dispersing for 20-30 min to obtain the treating agent. The dispersing time is short and the treating agent is not uniform. Long dispersion time and low efficiency.

And S2, coating the treating agent on weathering steel to complete the coating treatment.

Further, the surface roughness of the weathering steel is 2.50-3.50 μm.

The surface shot blasting treatment is carried out on the weathering steel, so that the surface roughness of the weathering steel is 2.50-3.50 mu m, and the adhesive force between the treating agent and the weathering steel can be improved. The higher the roughness, the stronger the adhesion, but too high a roughness will cause damage to the substrate and easily cause local corrosion. The lower the roughness, the weaker the adhesion.

Further, the thickness of the coating film is 20-40 μm.

After the coating treatment is finished, the coating can be used after being naturally dried for one week.

The weathering steel surface rust layer stabilizing agent and the weathering steel surface coating film treatment method of the present application will be described in detail with reference to examples, comparative examples and experimental data.

Examples 1 to 6 tests were carried out using weathering steels of the following chemical composition: c: 0.04%, Si: 0.29%, Mn: 1.10%, P: 0.006%, S: 0.003%, Ni: 0.22%, Cr: 0.75%, Cu: 0.51%, Mo: 0.11%, and the balance of Fe and inevitable impurities.

Example 1

The treating agent comprises the following raw materials in parts by weight: 60 parts of polyvinyl butyral resin and 3 parts of Fe₂O₃0.5 part of phosphoric acid, 3 parts of chromium sulfate and 6 parts of Cr with the particle size of 1-30 mu m₂O₃2 parts of sodium molybdate, 0.1 part of surface additive BYk-310 part, 0.08 part of wetting dispersant BYK-101 part and 0.2 part of flatting agent BYK-300 part.

(1) Preparing a treating agent:

firstly, completely dissolving the polyvinyl butyral resin varnish into 10 times of absolute ethyl alcohol, then adding the dissolved polyvinyl butyral resin varnish into a high-speed dispersion machine, and weighing Fe according to the mass percentage₂O₃Phosphoric acid, chromium sulfate, Cr₂O₃The sodium molybdate, the surface additive, the wetting dispersant and the leveling agent are sequentially added into a high-speed dispersion machine and stirred while adding, wherein the rotating speed is 5000r/min, and the stirring time is 20-30 min.

(2) Sample preparation:

and carrying out surface shot blasting treatment on the weathering steel to ensure that the surface roughness of the weathering steel is 2.50-3.50 mu m, and then carrying out surface oil removal.

(3) Coating treatment:

and (3) coating the uniformly dispersed treating agent obtained in the step (1) on the weather-resistant steel substrate treated in the step (2) by using a brush coating or spraying method, wherein the thickness of a dry film is 20-40 mu m, and naturally drying for one week.

Example 2

The treating agent comprises, by mass, 65 parts of water-based acrylic resin, 6 parts of FeO, 1 part of sodium phosphate, 6 parts of chromium sulfate, 2 parts of CaO with the particle size of 120-500 nm, 3 parts of sodium molybdate, 0.2 part of a surface additive BYK-378, 0.15 part of a wetting dispersant BYK-130 and 0.12 part of a flatting agent BYK-306.

The treating agent preparation, sample preparation and coating treatment were the same as in example 1.

Example 3

The weathering steel surface coating treatment agent comprises 70 parts of polyvinyl butyral resin varnish and 4 parts of Fe by weight percentage₃O₄1 part of potassium phosphate, 3.5 parts of chromium sulfate and 8 parts of Al with the particle size of 20-30 mu m₂O₃5 parts of sodium molybdate, 0.26 part of surface additive BYK-378, 0.25 part of wetting dispersant BYK-160 and 0.23 part of flatting agent BYK-361.

Example 4

The weathering steel surface coating film treating agent comprises 75 parts of waterborne acrylic resin and 2 parts of iron oxide according to weight percentage, wherein the waterborne acrylic resin comprises FeO and Fe₂O₃And Fe₃O₄0.3 part of sodium phosphate, 1.5 parts of nickel sulfate, 9 parts of ZrO with the particle size of 10-30 mu m, 9 parts of sodium molybdate, 0.28 part of surface additive BYK-378, 0.16 part of wetting dispersant BYK-9076 and 0.34 part of flatting agent BYK-316N.

Example 5

The weathering steel surface coating treating agent comprises, by weight, 80 parts of polyvinyl butyral resin varnish, 9 parts of FeO and Fe₂O₃1 part of phosphoric acid, 4 parts of a mixture of chromium sulfate and nickel sulfate,wherein the weight portion ratio of the two is 1:1, 3 portions of Cr with the grain diameter of 300-800 nm₂O₃And CaO, wherein the weight parts of the sodium molybdate and the CaO are 1:1, 6 parts of sodium molybdate, 0.08 part of surface additive BYK-310, 0.36 part of wetting dispersant BYK-9076 and 0.38 part of flatting agent BYK-316N.

Example 6

The weathering steel surface coating treating agent comprises 55 parts of water-based acrylic resin and 4 parts of Fe in percentage by weight₂O₃And Fe₃O₄The mixture, 0.8 part of phosphoric acid, 5 parts of chromium sulfate, 4 parts of CaO and Al with the particle size of 5-25 mu m₂O₃The weight ratio of the two components is 1:1, 3 parts of sodium molybdate, 0.2 part of surface additive BYK-310, 0.4 part of wetting dispersant BYK-9076 and 0.13 part of flatting agent BYK-316N.

Comparative example 1

Comparative example 1 provides a weathering steel surface treatment agent, which comprises the following components, by weight, 45 parts of aqueous acrylic resin solution, and Cr (SO4)₃1.5 parts of Fe₂O₃2 parts of Fe₃O₄3 parts, 0.5 part of polyethylene glycol and 48 parts of water.

The treating agent with the proportion is uniformly coated on the surface of the weather-resistant steel substrate.

And (3) week immersion corrosion test:

the weathering steel surface of examples 1 to 6 and comparative example 1 was subjected to a periimmersion corrosion test, and the samples subjected to the coating treatment were placed in a periimmersion tank, and the impedance change of the samples was continuously tested for different times by using a 3.5% NaCl solution with reference to standard TB/T2375.

The weathering steel treatment agent coating samples prepared in examples 1 to 6 and comparative example 1 were subjected to immersion test for 28 days and 56 weeks, and no rust liquid sagging and flying-off occurred on the surface of the sample, as shown in FIGS. 1 to 3. After 56 days, bubbling and falling appear on the surface of the coating, and reaction products under the coating are integrated with a steel matrix. The ac impedance (EIS) at a frequency of 0.01Hz was measured on the weathering steel samples of examples 1 to 6 at 0 day, 28 days and 56 days of coating using the partat 4000 electrochemical workstation of princeton, and the impedance of the coated samples was found to increase significantly as shown in fig. 4, 5 and table 1, respectively.

TABLE 1

From the data in table 1, it can be seen that:

the resistance data of the weathering steel coating samples prepared in the embodiments 1 to 6 of the application in 0 day of coating is 1.85 to 1.95 multiplied by 10⁴And omega, compared with bare steel which is not coated with a film, the impedance of the coating is 100 times that of the bare steel and far exceeds that of the bare steel, and the higher the impedance is, the better the corrosion resistance is.

FIG. 1 shows the macro-morphology of 0 day soaking of weathering steel after the coating treatment of the embodiment of the present invention, FIG. 2 shows the macro-morphology of 28 days soaking of weathering steel after the coating treatment of the embodiment of the present invention, and FIG. 3 shows the macro-morphology of 56 days soaking of weathering steel after the coating treatment of the embodiment of the present invention, it can be seen from FIGS. 1 to 3 that the coating of weathering steel of the embodiment of the present invention peels off in a dotted manner with time, and the dotted peeling shows a tendency to become larger and larger with time, because the film forming material of the coating starts to decompose and peel with time aging, but the filler in the coating reacts to form a surface protective layer, and when the substrate is rusted, the protective layer blocks sagging of liquid, and no rusty sagging and flying phenomena of liquid rust occur.

FIG. 4 shows the impedance change of bare steel and the example coating film sample of the present invention in 0 day, 28 days and 56 days of immersion, the abscissa is the real impedance part and the ordinate is the imaginary impedance part; for clarity of the impedance under 0 day of bare steel immersion, the impedance under 0 day of bare steel immersion is shown in the interior of FIG. 4. FIG. 5 shows the impedance change of bare steel and the coating film sample of the embodiment of the present invention in 0 day, 28 days and 56 days of immersion, the abscissa is the AC frequency and the ordinate is the impedance modulus.

As can be seen from fig. 4 and 5, the impedance curve of the coated sample after being soaked for 56 days is far higher than that of the bare steel, and the higher the impedance is, the better the corrosion resistance of the surface is, so the corrosion resistance of the examples 1 to 5 of the present application is far higher than that of the bare steel.

As can be seen from the data of comparative example 1 in Table 1, the resistance of the weathering steel sample is 98 Ω for 0 day of coating film, and the resistance of the sample is 1.1X 10 for 28 days of coating film³Omega, 56 days of coating, and the impedance of the weathering steel sample is 2.3 multiplied by 10⁴Ω。

Compared with the comparative example 1, the weathering steel rust layer stabilized coating product of the embodiment of the invention has the advantage that the weathering steel is obviously better than the comparative example 1, and compared with the bare steel, the weathering steel rust layer stabilized coating product of the embodiment of the invention has the advantage that the weathering steel has obviously better impedance than the bare steel.

Through statistics, the formation time of the stable rust layer of the weathering steel sample of the embodiment 1-6 is 1-2 years. The formation time of the stable rust layer of the bare steel is 3-10 years.

The invention has at least the following advantages:

(1) the invention provides a weather-resistant steel surface coating product which takes polyvinyl butyral resin or polyvinyl butyral resin as a film forming substance, absolute ethyl alcohol as a solvent, Fe oxide, a phosphating agent, an accelerator, a modifier and a corrosion inhibitor as fillers and a surface auxiliary agent, a wetting dispersant and a leveling agent as film forming auxiliary agents.

(2) The treating agent is coated on the weathering steel, and 3.5% NaCl week immersion experiments show that the coating product can obviously improve the corrosion resistance of the weathering steel, and meanwhile, the corrosion resistance of the weathering steel coating sample is obviously improved along with the prolonging of week immersion time.

(3) The preparation of the treating agent and the coating treatment method for the surface of the weathering steel have the advantages of safe operation, simple process, low cost, good sample performance and easy realization of large-scale production.

(4) When the weathering steel subjected to the film coating treatment is used in a marine atmospheric environment, the surface film coating weathers and falls off after exposure, the filler in the film coating reacts with a steel matrix, a compact and stable rust layer can be quickly formed, the forming period is shortened to 1-2 years, the resistance is 100 times that of bare steel, the corrosion resistance is good, and the environmental pollution problems of rust liquid sagging, flying and the like are prevented.

Finally, it should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. The stabilizing treatment agent for the rust layer on the surface of the weathering resistant steel is characterized by comprising the following components in parts by weight:

film forming agent: 50-80 parts;

an inducer: 1-10 parts;

phosphating agent: 0.2-1 part;

accelerator (b): 1-5 parts;

modifying agent: 1-10 parts;

corrosion inhibitor: 1-10 parts;

surface auxiliary agent: 0.05-0.3 part;

wetting and dispersing agent: 0.05-0.4 part;

leveling agent: 0.05 to 0.4 portion.

2. The stabilizing agent for the rust layer on the surface of the weathering steel according to claim 1, wherein the film forming agent is any one of the following: polyvinyl butyral resin, and aqueous acrylic resin.

3. The stabilizing treatment agent for the rust layer on the surface of the weathering steel according to claim 1, wherein the inducing agent is at least one of the following: FeO, Fe₂O₃、Fe₃O₄。

4. The stabilizing agent for the rust layer on the surface of the weathering steel according to claim 1, wherein the phosphating agent is any one of the following: phosphoric acid, phosphate.

5. The stabilizing agent for the rust layer on the surface of the weathering steel according to claim 1, wherein the accelerator is at least one of the following: chromium sulfate, nickel sulfate.

6. The stabilizing agent for the rust layer on the surface of the weathering steel according to claim 1, wherein the modifying agent is at least one of the following: cr (chromium) component₂O₃、CaO、Al₂O₃ZrO, and the particle size of the modifier is 100 nm-50 mu m.

7. The stabilizing treatment agent for the rust layer on the surface of the weathering steel according to claim 1, characterized in that the stabilizing treatment agent further comprises 500-800 parts by weight of ethanol.

8. A method for coating a surface of weathering steel with the agent for stabilizing a rust layer on a surface of weathering steel according to any of claims 1 to 7, comprising,

mixing and stirring the raw materials and ethanol, and then dispersing to obtain a treating agent; the raw materials comprise the following components in parts by weight: film forming agent: 50-80 parts; 1-10 parts of an inducer; phosphating agent: 0.2-1 part; accelerator (b): 1-5 parts; 1-10 parts of a modifier; corrosion inhibitor: 1-10 parts; surface auxiliary agent: 0.05-0.3 part; wetting and dispersing agent: 0.05-0.4 part; leveling agent: 0.05-0.4 part;

9. The method for coating the surface of the weathering steel according to claim 8, wherein the weathering steel has a surface roughness of 2.50 to 3.50 μm.

10. The method for coating the surface of weathering steel according to claim 8, wherein the coating thickness is 20 to 40 μm.