A weathering steel surface rust layer stabilizing treatment agent for industrial atmospheric environments

Abstract

The application provides a weathering steel surface rust layer stabilizing treatment agent for industrial atmospheric environment, and the chemical composition of the weathering steel surface rust layer stabilizing treatment agent is as follows in terms of mass fraction: 25-45% of acrylic resin, 2.0-6.0% of chromium sulfate, 3.0-8.0% of ferrous oxide, 2.0-6.0% of ferric oxide, 0.5-3.5% of copper sulfate, 0.3-1.5% of sodium bisulfite, 1.0-6.0% of sodium molybdate, 0.5-3.5% of nickel sulfate, 2.0-5.0% of potassium phosphate, 0.05-0.5% of surfactant, 0.05-0.5% of defoaming agent, 0.05-0.5% of dispersing agent, 0.05-0.5% of thickening agent, and the balance is water, wherein the amount of plasticizer added is 2-5% of the resin. The stabilizing treatment agent in the application can promote the weathering steel surface to form a stable and dense rust layer within 0.5-1 year after the surface of the weathering steel is treated before use.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of corrosion and protection, in particular to a surface rust layer stabilizing treatment agent for weathering steel in industrial atmospheric environment. BACKGROUND

[0002] Weathering steel, also known as atmospheric corrosion resistant steel, is a kind of steel that adds a small amount of Cu, P, Cr, Ni and other alloy elements on the basis of carbon steel, so as to form a dense protective layer on the surface of the metal matrix to prevent further corrosion. Its comprehensive effect is "rust to stop rust", and its atmospheric corrosion resistance is 2-8 times that of ordinary carbon steel. Therefore, weathering steel is widely used in industries such as containers, bridges, automobiles, railway vehicles and buildings.

[0003] The stable weathering steel surface rust layer is composed of a loose and porous outer rust layer and a continuous and dense inner rust layer. The corrosion resistance of weathering steel mainly comes from the inner rust layer. Alloy elements are enriched and precipitated in the inner rust layer, which improves the stability and density of the inner rust layer. The inner rust layer is mainly composed of continuous and dense Fe3O4, α-FeOOH and amorphous hydroxyl oxide (FeO X (OH), X = 0-1). The outer rust layer is mainly composed of loose and porous β-FeOOH and γ-FeOOH.

[0004] Related studies have shown that in the industrial atmospheric environment, when the α / γ* of the rust layer is greater than 1 (α refers to the content of α-FeOOH, and γ* refers to the total content of Fe3O4, γ-FeOOH and β-FeOOH), the corrosion rate of the steel is less than 0.01 mm / a, which can be considered as the formation of a stable rust layer.

[0005] Weathering steel can use the protective stable rust layer generated by itself to prevent further corrosion in the natural environment, which saves the cost of painting and later maintenance. However, it takes 3-10 years for weathering steel to completely form a stable rust layer in the atmospheric environment. Before the formation of the stable rust layer, problems such as rust liquid flowing and scattering often occur, which seriously pollute the surrounding environment and seriously affect the consistency of the appearance color of weathering steel, which has become a bottleneck problem limiting the promotion and application of weathering steel without painting.

[0006] In order to solve this problem, there are generally two protection methods in the actual use of weathering steel. The first method is to use painting as ordinary carbon steel, but painting greatly increases the use cost and operation process, and it is also difficult to implement for large components. The second method is to use surface stabilization treatment technology, which is to treat the surface of weathering steel before use to shorten the formation process and time of the stable rust layer on the surface of weathering steel. This technology can not only avoid the phenomenon of yellow rust liquid flowing in the early stage of weathering steel use to prevent pollution, but also form a stable protective rust layer on the surface.

[0007] Researchers have done a lot of research and developed some practical rust layer stabilization treatment technologies, such as weather-resistant coating treatment, oxide coating treatment, rust coating treatment, etc. However, with the intensification of industrial pollution, carbon oxides, sulfides, soot, dust, etc. in the industrial atmosphere, especially SO2, Cl - , CO2 and other substances can accelerate the corrosion of metals, coatings and other materials, and seriously reduce their performance and durability. These technologies cannot well stabilize the rust layer when used on weathering steels. The rust liquid hanging and scattering of the rust layer on the surface of the weathering steel occur in the early stage of the stabilization process. The existing process is complex, the treatment liquid is toxic, the environment is polluted, and the cost is high.

[0008] Therefore, how to develop a weathering steel surface stabilization treatment agent that can inhibit the rust liquid hanging and scattering of weathering steel in an industrial atmospheric environment, accelerate the formation of the rust layer on the surface of the weathering steel, and has a simple preparation process, is environmentally friendly and non-toxic, and has low production cost, has become a technical problem to be solved. SUMMARY

[0009] Therefore, the present application aims to provide a weathering steel surface rust layer stabilization treatment agent for industrial atmospheric environment. In order to solve the technical problems in the prior art that the conventional weathering steel surface treatment technology cannot well stabilize the rust layer in the industrial atmospheric environment, the air contains a lot of SO2, Cl - , CO2, etc. The rust liquid hanging and scattering of the rust layer on the surface of the weathering steel occur in the early stage of the stabilization process. The existing process is complex, the treatment liquid is toxic, the environment is polluted, and the cost is high.

[0010] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0011] A weathering steel surface rust layer stabilization treatment agent for industrial atmospheric environment, the chemical composition of the weathering steel surface rust layer stabilization treatment agent is as follows: acrylic resin 25-45%, chromium sulfate 2.0-6.0%, diiron trioxide 3.0-8.0%, triiron tetroxide 2.0-6.0%, copper sulfate 0.5-3.5%, sodium bisulfite 0.3-1.5%, sodium molybdate 1.0-6.0%, nickel sulfate 0.5-3.5%, potassium phosphate 2.0-5.0%, surfactant 0.05-0.5%, defoaming agent 0.05-0.5%, dispersant 0.05-0.5%, thickening agent 0.05-0.5%, and the balance is water, wherein the amount of plasticizer added is 2-5% of the amount of acrylic resin.

[0012] The raw material components in the stabilizing treatment agent in the setting synergize with each other, when the weathering steel surface stabilizing treatment agent is applied on the weathering steel substrate, through physical, chemical and electrochemical reactions, a stable and dense rust layer is formed, which allows air and water to enter, and at the same time accelerates the formation of the stable rust layer, the formation time of the stable rust layer can be shortened to 0.5-1 year, avoiding the environmental pollution problems such as rust liquid dripping and scattering during the formation of the protective rust layer.

[0013] Further, the PH value of the weathering steel surface rust layer stabilizing treatment agent is 2.8-3.5.

[0014] In the setting, by adjusting the PH value of the weathering steel surface rust layer stabilizing treatment agent to 2.8-3.5, the resin film formed on the surface of the weathering steel can quickly improve the rust layer resistance of the weathering steel, effectively inhibit the electrochemical corrosion, and reduce the corrosion rate and the conductivity.

[0015] Further, the surfactant is OP-10, the defoaming agent is type 6800 defoaming agent, the dispersing agent is BYK-220S type dispersing agent, the thickening agent is WT105A type thickening agent, and the plasticizer is Texnaol alcohol ester 12 type plasticizer.

[0016] Further, the chemical composition of the weathering steel includes, in terms of mass fraction: C: 0.083-0.087%, Si: 0.54-0.58%, Mn: 1.21-1.25%, S: 0.023-0.027%, P: 0.030-0.034%, Cr: 0.62-067%, Ni: 1.21-1.25%, Mo: 0.33-0.37%, Cu: 0.43-0.45%, RE: 0.033-0.037%, and the balance is Fe and unavoidable impurities.

[0017] Further, the preparation method of the weathering steel surface rust layer stabilizing treatment agent includes the following steps: first, mix the acrylic resin and water for 0.5-1 h, so that the acrylic resin and water are fully mixed and dissolved, and the solution properties are uniform; then, sequentially add chromium sulfate, copper sulfate, sodium bisulfite, sodium molybdate, nickel sulfate, potassium phosphate, ferric tetroxide and ferrous oxide, mix for 0.5-1 h, and mix uniformly; finally, add the surfactant, defoaming agent, dispersing agent, thickening agent and plasticizer, stir for 3-4 h, mix uniformly, detect the PH value of the mixture, and adjust with acid or acidic salt to ensure that the PH value of the mixture is controlled between 2.8 and 3.5. Preferably, sodium bisulfite is used to adjust the PH value.

[0018] The setting can make the mixture more uniform, and the method also makes the treatment agent more stable in forming the rust layer on the surface of the weathering steel.

[0019] Further, the use method of the weathering steel surface rust layer stabilizing treatment agent comprises the following steps:

[0020] Step one, sequentially performing shot blasting treatment and sand blasting treatment on the surface of the weathering steel;

[0021] Step two, obtaining the weathering steel surface rust layer stabilizing treatment agent according to claim 1;

[0022] Step three, using the weathering steel surface rust layer stabilizing treatment agent to perform surface rust layer stabilizing treatment on the weathering steel after step one, so as to obtain weathering steel with a stabilized surface rust layer.

[0023] Further, the weathering steel comprises one of weathering steel plate, weathering steel bar and weathering steel casting.

[0024] Further, in step three, the specific steps of the stabilizing treatment method are as follows: uniformly brushing the weathering steel surface rust layer stabilizing treatment agent on the surface of the weathering steel, then drying, completing one brushing operation, and repeating the brushing operation 1-2 times to complete the surface rust layer stabilizing treatment.

[0025] Further, in step one, the surface roughness Ra of the treated weathering steel is less than or equal to 12.5 μm. Preferably, the surface roughness Ra of the treated weathering steel is less than or equal to 5-10 μm.

[0026] Further, in step three, the coating film thickness after the surface rust layer stabilizing treatment is 0.22-0.3 μm.

[0027] Compared with the prior art, the weathering steel surface rust layer stabilizing treatment agent for industrial atmospheric environment has the following advantages:

[0028] (1) The weathering steel surface rust layer stabilizing treatment agent is obtained by combining various chemical components and controlling the proportion of raw materials. When the weathering steel surface rust layer stabilizing treatment agent is used to treat the weathering steel base body, a stable and dense rust layer is formed, which allows air and water to enter and accelerates the formation of the stable rust layer. The formation time of the stable rust layer can be shortened to 0.5-1 year, and the environmental pollution problems such as rust liquid dripping and scattering during the formation of the protective rust layer are avoided.

[0029] (2) The weathering steel surface rust layer stabilizing treatment agent is increased by sodium bisulfite. The PH of the weathering steel surface rust layer stabilizing treatment agent is adjusted by sodium bisulfite, so that it is controlled at 2.8-3.5. The resistance of the resin film formed on the surface of the weathering steel is 120 times that of bare steel. The surface rust layer stabilizing treatment can quickly improve the rust layer resistance of the weathering steel, effectively inhibit the electrochemical corrosion, and reduce the corrosion rate and the conductivity.

[0030] (3) The resin film formed on the surface of the weathering steel by using the stabilizing treatment agent of the present application is a porous film, and can allow a certain amount of air and water to pass through to the metal substrate to cause corrosion and promote the formation of a rust layer. Meanwhile, the presence of the resin film effectively controls the speed of corrosion occurrence, which is conducive to the formation of a stable rust layer on the surface of the weathering steel.

[0031] (4) The resin film formed on the surface of the weathering steel by using the stabilizing treatment agent of the present application can prevent the running and scattering of the rust liquid produced in the early stage of corrosion, eliminate the soil and environmental pollution caused by the running and scattering of the rust liquid in the early stage of engineering application, and improve the use advantages of the weathering steel in the industrial atmospheric environment. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The scanning electron microscope image of the rust layer on the surface of the weathering steel to which the rust layer stabilizing treatment agent in Example 1 is applied on the surface of the weathering steel;

[0033] Figure 2 The scanning electron microscope image of the rust layer on the surface of the weathering steel to which the rust layer stabilizing treatment agent in Example 2 is applied on the surface of the weathering steel;

[0034] Figure 3 The scanning electron microscope image of the rust layer on the surface of the weathering steel to which the rust layer stabilizing treatment agent in Example 3 is applied on the surface of the weathering steel;

[0035] Figure 4 The scanning electron microscope image of the rust layer on the surface of the weathering steel which is not treated by the rust layer stabilizing treatment agent in Comparative Example 1;

[0036] Figure 5 The scanning electron microscope image of the rust layer on the surface of the weathering steel to which the rust layer stabilizing treatment agent in Comparative Example 2 is applied on the surface of the weathering steel;

[0037] Figure 6 The scanning electron microscope image of the rust layer on the surface of the weathering steel to which the rust layer stabilizing treatment agent in Comparative Example 3 is applied on the surface of the weathering steel;

[0038] Figure 7 The scanning electron microscope image of the rust layer on the surface of the weathering steel to which the rust layer stabilizing treatment agent in Comparative Example 4 is applied on the surface of the weathering steel. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0040] The application discloses a weathering steel surface rust layer stabilizing treatment agent for an industrial atmosphere environment, and relates to the technical field of weathering steel surface rust layer stabilizing treatment agents. The weathering steel surface rust layer stabilizing treatment agent is applied in an industrial atmosphere environment, and the chemical composition of the weathering steel surface rust layer stabilizing treatment agent is as follows in terms of mass fraction: 25-45% of acrylic resin, 2.0-6.0% of chromium sulfate, 3.0-8.0% of diiron trioxide, 2.0-6.0% of triiron tetroxide, 0.5-3.5% of copper sulfate, 0.3-1.5% of sodium bisulfite, 1.0-6.0% of sodium molybdate, 0.5-3.5% of nickel sulfate, 2-5% of potassium phosphate, 0.05-0.5% of a surfactant, 0.05-0.5% of a defoaming agent, 0.05-0.5% of a dispersing agent, 0.05-0.5% of a thickening agent, 2-5% of a plasticizer, and the rest is water, wherein the pH of the weathering steel surface rust layer stabilizing treatment agent is 2.8-3.5.

[0041] The acrylic resin in the application is water-soluble acrylic resin, the water-soluble acrylic acid is used as a film-forming agent, the water-soluble acrylic resin film not only has good weather resistance and corrosion resistance, but also has the characteristics of a porous grid, allowing a certain amount of air and water to penetrate the resin film to reach the steel substrate and react with the steel substrate, accelerating the growth and conversion of the weathering steel rust layer until a stable rust layer is formed, and meanwhile, the resin film can prevent environmental pollution problems caused by the running and scattering of the rust liquid in the initial corrosion stage.

[0042] The Cr2(SO4)3 and Ni2SO4 in the application are used as accelerators, the Cr2(SO4)3 can react with water to generate Cr2(SO4)3→2Cr 3+ +3SO 2 4 - , and the generated SO 2 4 - can accelerate the initial corrosion speed of the weathering steel and promote the generation of alpha-FeOOH in the rust layer; the generated Cr 3+ can replace Fe in the alpha-FeOOH in the rust layer, and generate more stable and dense alpha-(Fe 1-x Cr X )OOH at the joint between the rust layer and the substrate, thereby improving the resistance of the rust layer to the corrosion medium transmission process. The Ni 2+ promotes the formation of a nano-scale network structure such as Fe2NiO4 in the rust layer, and improves the corrosion resistance of the rust layer.

[0043] The Na2MoO4 and K3PO4 in the application are used as corrosion inhibitors, the Na2MoO4 is used as an oxidant, is dispersed in the rust layer to promote the generation of a hardly soluble molybdate and is attached to the surface of the substrate, thereby inhibiting the dissolution of the substrate in a pitting pit, inhibiting the diffusion of pitting, and improving the corrosion resistance of the rust layer. The K3PO4 can react with Fe 2+ and Mo 6+The metal cations form insoluble salts and are adsorbed on the surface of the weathering steel, passivating the surface of the substrate and hindering the dissolution of the rust layer, while Fe 2+ precipitates and oxidizes to Fe 3+ , thus obtaining iron oxyhydroxide FeOOH in the coating film and promoting the formation of α-FeOOH in the rust layer.

[0044] The CuSO4 in the present application acts as a passivation agent, and copper is secondarily precipitated in the rust layer, activating the cathode and passivating the anode, slowing down the electrochemical corrosion and enhancing the corrosion resistance of the weathering steel.

[0045] The NaHSO3 in the present application can adjust the pH of the rust layer stabilizing treatment agent on the surface of the weathering steel, promote the initial corrosion rate of the weathering steel, and shorten the time for forming a stable rust layer on the weathering steel.

[0046] The Fe3O4 in the present application acts as an inducer, inducing the conversion process of the rust layer, shortening the rust layer stabilization period, and accelerating the formation of α-FeOOH with good stability and protection.

[0047] The iron red Fe2O3 in the present application acts as a toning agent, keeping the color of the treated rust layer consistent with that of the natural rust layer.

[0048] The solvent in the present application is water, which can reduce environmental pollution.

[0049] The OP-10 in the present application acts as a surfactant, improving wettability and making the film uniform.

[0050] The 6800 type defoaming agent in the present application can eliminate bubbles in the resin film.

[0051] The BYK-220S type dispersant in the present application can ensure uniform distribution of chemicals in the resin and improve the consistency of the stabilized rust layer on the surface of the weathering steel.

[0052] The WT105A type thickening agent in the present application can ensure that the added chemicals and resin and water do not separate and precipitate, ensuring the consistency of the solution.

[0053] The Texnaol alcohol ester 12 type plasticizer in the present application can improve the plasticity and low-temperature crack resistance of the resin film.

[0054] A method for using a weathering steel surface rust layer stabilizing treatment agent for industrial atmospheric environments:

[0055] S1, surface pretreatment of weathering steel substrate; shot blasting treatment + sand blasting treatment of weathering steel surface. The weathering steel surface is treated by shot blasting to close the micro defects on the weathering steel surface, improve the density of the weathering steel surface layer, and produce compressive stress on the weathering steel surface, thereby improving the corrosion resistance of the weathering steel surface, achieving uniform corrosion of the weathering steel surface, avoiding pitting corrosion caused by micro defects, and affecting the formation of the weathering steel stable rust layer. The weathering steel surface treated by shot blasting is treated by sand blasting to remove the loose rust and iron ions on the weathering steel surface and activate the weathering steel surface; at the same time, the surface edges are smoothed by the impact and friction of the sand particles on the shot blasted surface (shot blasting causes pits on the weathering steel surface), thereby improving the roughness of the weathering steel surface. By sand blasting the weathering steel surface treated by shot blasting, the adhesion between the weathering steel surface and the stable treatment agent film and the uniformity of the stable treatment agent film can be improved, and the stable treatment agent film on the weathering steel surface can be prevented from falling off before the formation of the stable rust layer, thereby affecting the formation of the weathering steel stable rust layer.

[0056] S2, preparation of weathering steel surface rust layer stabilizing treatment agent

[0057] First, the acrylic resin and water are mixed for 0.5-1 hours to ensure that the acrylic resin and water are fully mixed and dissolved, and the solution properties are uniform; then, the chromium sulfate, copper sulfate, sodium bisulfite, sodium molybdate, nickel sulfate, potassium phosphate, ferrous ferric oxide, and ferrous ferric oxide are sequentially added and mixed for 0.5-1 hours to ensure that the materials are uniformly mixed; finally, the surface active agent, defoaming agent, dispersing agent, thickening agent, and plasticizer are added and stirred at low speed for 3-4 hours, and the mixture is mixed uniformly. The PH value of the mixture is detected, and the mixture PH value can be adjusted with acid or acidic salt to ensure that the mixture PH value is controlled to 2.8-3.5. The mixture can be used when there are no bubbles overflowing or appearing.

[0058] S3, brushing the weathering steel surface rust layer stabilizing treatment agent onto the weathering steel substrate

[0059] The weathering steel surface rust layer stabilizing treatment agent is uniformly brushed on the surface of the weathering steel substrate, and then dried to complete one brushing operation. The brushing operation is repeated 1-2 times to complete the surface rust layer stabilization treatment.

[0060] The chemical composition of the weathering steel serving in the industrial atmospheric environment is 0.085% C, 0.56% Si, 1.23% Mn, 0.025% S, 0.032% P, 0.65% Cr, 1.23% Ni, 0.35% Mo, 0.45% Cu, and 0.035% RE.

[0061] The weathering steel surface rust layer stabilizing treatment agent for industrial atmospheric environment according to the present application will be described in detail below with reference to examples, comparative examples, and experimental data.

[0062] Example 1

[0063] The chemical composition of the rust layer stabilizing agent for the surface of weathering steel is shown in Table 1 below. After the surface of the weathering steel is pretreated, the rust layer stabilizing agent of the present application is applied to the surface of the weathering steel. The rust layer stabilizing agent is prepared according to the formulation shown in Table 2. The rust layer stabilizing agent is uniformly applied to the surface of the weathering steel sample using a brush, and is naturally dried in a room for 24 hours. The rust layer stabilizing agent is applied twice, and the thickness of the rust layer stabilizing agent film is 0.28 μm. The weathering steel sample is subjected to an industrial atmospheric environment test for 0.6 years, and a stable rust layer is formed, as shown in Fig. 1. Figure 1

[0064] Example 2

[0065] The chemical composition of the rust layer stabilizing agent for the surface of weathering steel is shown in Table 1 below. After the surface of the weathering steel is pretreated, the rust layer stabilizing agent of the present application is applied to the surface of the weathering steel. The rust layer stabilizing agent is prepared according to the formulation shown in Table 2. The rust layer stabilizing agent is uniformly applied to the surface of the weathering steel sample using a brush, and is naturally dried in a room for 24 hours. The rust layer stabilizing agent is applied twice, and the thickness of the rust layer stabilizing agent film is 0.28 μm. The weathering steel sample is subjected to an industrial atmospheric environment test for 0.6 years, and a stable rust layer is formed, as shown in Fig. 1. Figure 2

[0066] Example 3

[0067] The chemical composition of the rust layer stabilizing agent for the surface of weathering steel is shown in Table 1 below. After the surface of the weathering steel is pretreated, the rust layer stabilizing agent of the present application is applied to the surface of the weathering steel. The rust layer stabilizing agent is prepared according to the formulation shown in Table 2. The rust layer stabilizing agent is uniformly applied to the surface of the weathering steel sample using a brush, and is naturally dried in a room for 24 hours. The rust layer stabilizing agent is applied twice, and the thickness of the rust layer stabilizing agent film is 0.28 μm. The weathering steel sample is subjected to an industrial atmospheric environment test for 0.6 years, and a stable rust layer is formed, as shown in Fig. 1. Figure 3

[0068] Table 1 Formulation of the rust layer stabilizing agent for the surface of weathering steel according to the present application (wt%)

[0069]

[0070] Comparative Example 1

[0071] The difference between the present comparative example and Example 3 is that the rust layer stabilizing agent of the present application is not applied to the surface of the weathering steel after the surface of the weathering steel is pretreated. The rust layer formed is shown in Fig. 1. Figure 4

[0072] Comparative Example 2

[0073] The difference between the present comparative example and Example 3 is that the amount of NaHSO3 added to the rust layer stabilizing agent for the surface of weathering steel is 0.08%. The rust layer formed is shown in Fig. 1. Figure 5

[0074] ​​​​​Comparative Example 3

[0075] The difference between the present comparative example and Example 3 is that the amount of NaHSO3 added in the weathering steel rust layer stabilizing treatment agent is 2.5%, and the generated rust layer is as shown in Figure 6 .

[0076] Comparative Example 4

[0077] The difference between the present comparative example and Example 3 is that the weathering steel rust layer stabilizing treatment agent does not add NaHSO3, and the generated rust layer is as shown in Figure 7 .

[0078] It can be known from Figures 1-7 that the weathering steel surface rust layer after being treated by the weathering steel rust layer stabilizing treatment agent of the present application is continuous and dense, and has stronger protection.

[0079] The weathering steels prepared in each example and each comparative example are subjected to an accelerated corrosion test analysis, and the analysis method is as follows: the samples in each group are placed in a circumfluence test box, and the test is performed in accordance with TB / T2375, in a Q-Fog CCT600 type salt spray chamber, the test solution is 3.5% NaCl solution, and the test conditions are as follows: temperature 45℃; humidity 70%; 4h is a test cycle, spraying for 2h and drying for 2h, the sample is vertically hung, and the corrosion rate is counted in different cycles. The rust liquid dripping conditions of each group are observed and counted during the accelerated corrosion test, and the evaluation standard from small to large according to the dripping amount is as follows: no rust liquid dripping, very small amount of rust liquid dripping, small amount of rust liquid dripping, relatively large amount of rust liquid dripping, and large amount of rust liquid dripping; the corrosion rates of the samples after 5 cycles are as shown in Table 2.

[0080] Table 2

[0081]

[0082] It can be known from the data in Examples 1-3 and Comparative Examples 1-4 of the present application that the surface of the weathering steel after being treated by the present application has no rust liquid dripping, which indicates that the treatment agent of the present application has good effects of promoting rust layer stabilization and preventing the dripping of rust liquid during the rust layer formation process, and the corrosion rates of the weathering steels in Examples 1-3 are 0.26g / m 2 ·h~0.34g / m 2 ·h after 5 cycles, and the period for forming a stable and dense layer is shorter.

[0083] Although the present application is disclosed as above, the present application is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and therefore the protection scope of the present application should be subject to the scope defined by the claims.

Claims

1. A rust stabilizing agent for weathering steel surfaces used in industrial atmospheric environments, characterized in that, The chemical composition of the weathering steel surface rust stabilizing agent, by mass fraction, is as follows: acrylic resin 25-45%, chromium sulfate 2.0-6.0%, ferric oxide 3.0-8.0%, ferric oxide 2.0-6.0%, copper sulfate 0.5-3.5%, sodium bisulfite 0.3-1.5%, sodium molybdate 1.0-6.0%, nickel sulfate 0.5-3.5%, potassium phosphate 2.0-5.0%, surfactant 0.05-0.5%, defoamer 0.05-0.5%. The composition includes 0.05-0.5% dispersant, 0.05-0.5% thickener, plasticizer, and the balance being water, wherein the amount of plasticizer added is 2-5% of the acrylic resin; the pH value of the weathering steel surface rust stabilizing agent is 2.8-3.5; the surfactant is OP-10, the defoamer is type 6800 defoamer, the dispersant is type BYK-220S dispersant, the thickener is type WT105A thickener, and the plasticizer is type Texnaol ester 12 plasticizer.

2. The weathering steel surface rust stabilizing agent according to claim 1, characterized in that, The chemical composition of the weathering steel, calculated by mass fraction, includes: C: 0.083–0.087%, Si: 0.54–0.58%, Mn: 1.21–1.25%, S: 0.023–0.027%, P: 0.030–0.034%, Cr: 0.62–0.67%, Ni: 1.21–1.25%, Mo: 0.33–0.37%, Cu: 0.43–0.45%, RE: 0.033–0.037%, with the balance being Fe and unavoidable impurities.

3. The weathering steel surface rust stabilizing agent according to claim 1, characterized in that, The preparation method of the weathering steel surface rust stabilizing agent includes the following steps: First, mix acrylic resin and water for 0.5-1 hour to allow the acrylic resin and water to fully mix and dissolve, ensuring uniform solution characteristics; then, add chromium sulfate, copper sulfate, sodium bisulfite, sodium molybdate, nickel sulfate, potassium phosphate, ferric oxide, and ferric oxide sequentially and mix for 0.5-1 hour until homogeneous; finally, add surfactant, defoamer, dispersant, thickener, and plasticizer, stir for 3-4 hours until homogeneous, and then test the pH value of the mixture. Use sodium bisulfite to adjust the pH value to ensure that the pH value of the mixture is controlled between 2.8 and 3.

5.

4. The weathering steel surface rust stabilizing agent according to any one of claims 1-3, characterized in that, The method of using the weathering steel surface rust stabilizing agent includes the following steps: Step 1: Perform shot blasting and sandblasting treatments on the surface of the weathering steel in sequence; Step 2: Obtain the rust stabilizing agent for weathering steel as described in claim 1; Step 3: Use a weathering steel surface rust stabilizer to stabilize the surface rust layer of the weathering steel treated in Step 1, so as to obtain weathering steel with a stabilized surface rust layer.

5. The weathering steel surface rust stabilizing agent according to claim 1, characterized in that, The weathering steel includes one of weathering steel plates, weathering steel bars, and weathering steel castings.

6. The weathering steel surface rust stabilizing agent according to claim 4, characterized in that, In step three, the specific steps of the stabilization treatment method are as follows: the weathering steel surface rust layer stabilizing agent is evenly brushed onto the weathering steel surface, and then dried to complete one brushing operation. The brushing operation is repeated 1 to 2 times to complete the surface rust layer stabilization treatment.

7. The weathering steel surface rust stabilizing agent according to claim 4, characterized in that, In step one, the surface roughness Ra of the treated weathering steel is ≤12.5μm.

8. The weathering steel surface rust stabilizing agent according to claim 4, characterized in that, In step three, the coating thickness after surface rust stabilization treatment is 0.22–0.3 μm.

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