CN-121975363-A - Coating-free carbon steel medium plate and preparation method thereof

Abstract

The invention discloses a coating-free carbon steel medium plate and a preparation method thereof. The preparation method comprises the following steps of mixing nano alloy powder and a dispersing agent according to the mass ratio, dispersing in an ultrasonic dispersing instrument to obtain nano alloy slurry, adding tetraethoxysilane, maleic anhydride, polyurethane resin, a silane coupling agent, isocyanate, polysiloxane and a leveling agent into the nano alloy slurry according to the mass ratio, stirring, adding a defoaming agent, and stirring to obtain a nano modified coating material, and step 2, coating the nano modified coating material after pre-coating the steel plate, heating to 150-200 ℃ and preserving heat for 5-10min until the surface coating is completely solidified to obtain the coating-free carbon steel medium plate. The corrosion-resistant modified carbon steel plate solves the problem that the existing carbon steel plate is easy to rust by carrying out corrosion-resistant modification treatment on the surface of the carbon steel medium plate, and meanwhile, the product reduces the procedures and emission problems in the downstream steel structure processing and manufacturing process, reduces the production cost, improves the production efficiency and reduces the emission of VOCs.

Inventors

• LIU WEIHANG
• LIU WEILI
• HE DAN
• LI QINGQI

Assignees

• 宝钢湛江钢铁有限公司

Dates

Publication Date

20260505

Application Date

20260313

Claims (5)

1. 1. The coating-free carbon steel medium plate is characterized by being prepared by coating a nanocrystallization modified coating material on the surface of a steel plate, wherein the nanocrystallization modified coating material comprises, by mass, 5-10 parts of tetraethoxysilane, 10-15 parts of maleic anhydride, 10-15 parts of polyurethane resin, 15-25 parts of a silane coupling agent, 20-40 parts of isocyanate, 5-10 parts of polysiloxane, 5-10 parts of a dispersing agent, 2-5 parts of nano alloy powder, 0.5-1 part of a leveling agent and 0.5-1 part of a defoaming agent.
2. 2. The method for preparing a coating-free carbon steel medium plate as claimed in claim 1, wherein the nano alloy powder is nano zinc powder with a particle diameter of 50-100nm.
3. 3. The method for preparing the coating-free carbon steel medium plate according to claim 1, which is characterized in that the method comprises the following steps: Step 1, mixing nano alloy powder and a dispersing agent according to the mass ratio, and then dispersing in an ultrasonic dispersing instrument for 8-12 hours to obtain nano alloy slurry, adding tetraethoxysilane, maleic anhydride, polyurethane resin, a silane coupling agent, isocyanate, polysiloxane and a leveling agent into the nano alloy slurry according to the mass ratio, stirring at the stirring speed of 400-600r/min for 1-2 hours, adding a defoaming agent, and stirring for 10-20 minutes to obtain the nano modified coating material; and 2, coating the nanocrystallization modified coating material after pre-coating pretreatment on the steel plate, heating to 150-200 ℃ and preserving heat for 5-10min until the surface coating is completely solidified to obtain the coating-free carbon steel medium plate.
4. 4. The preparation method of the coating-free carbon steel medium plate according to claim 3, wherein in the step 2, the pretreatment before coating of the steel plate comprises the specific steps of spraying alkali liquor on the steel plate, wiping and degreasing the steel plate by a rolling brush, spraying and cleaning by clean water, baking the steel plate by a heating furnace, removing water on the surface and heating to 40-60 ℃, removing oxide skin and rust on the surface of the steel plate by a mechanical cleaning method, and purging the surface of the steel plate to remove residual dust on the surface of the steel plate.
5. 5. The method for producing a non-coated carbon steel medium plate according to claim 3, wherein the coating method is spray coating, roll coating or curtain coating.

Description

Coating-free carbon steel medium plate and preparation method thereof Technical Field The invention relates to the technical field of rust prevention of steel plates, in particular to a coating-free carbon steel medium plate and a preparation method thereof. Background The consumption amount of the steel plate (pipe) for engineering structure per year is up to hundreds of millions of tons, and the use of the product relates to various aspects of national economy construction, such as engineering machinery, structural building, transportation ship, metallurgical equipment, engineering building, petrochemical industry, aerospace, energy power generation and other industries. The problems of corrosion on the surface of the steel materials in the production, storage and transportation processes are all the problems of easy corrosion of the carbon steel in the aspects of machinery, structure, equipment, construction and the like related to the steel materials, and the problems of easy corrosion of the carbon steel are all the time pain points restricting the development and the use of the carbon steel materials. Despite the many protective measures taken on the steel surface, iron lost by rust worldwide annually still accounts for 25% of annual worldwide production. Most equipment structures with requirements on corrosion resistance can only be made of stainless steel or composite materials, which greatly increases the manufacturing cost of downstream user industries. In order to delay the corrosion of carbon steel structures, the means commonly used at present mainly comprise painting, plastic coating, metal plating, ceramic coating spraying and the like. However, the precondition of the corrosion-resistant treatment is that the surface of the steel plate needs to be cleaned, including processes such as shot blasting, ash removal, degreasing, phosphating and the like, and the steel plate still has the problem of rust in the process of waiting for each procedure at intervals. Therefore, in order to ensure effective coating of the surface of the steel sheet, some users even need to perform repeated operations on the above-mentioned process several times. The rust problem of the carbon steel structure in the processing process can be effectively solved by coating the surface of the steel plate in advance, but the original cutting, bending, welding and other performances of the steel plate are affected, the coating process of the corrosion-resistant layer is generally carried out after the steel plate is structurally spliced, the coating area is still difficult to reach 100% in the construction process, a longer process interval exists between the rust removal and spraying processes, the rust removal is caused by secondary rust of the steel plate, and the emission of volatile organic compounds in the spraying process exceeds the standard. Therefore, if a steel functional product with excellent corrosion resistance on the surface can be developed, the corrosion prevention procedures of downstream users in the processing and using processes can be reduced, and meanwhile, the corrosion prevention and resistance of the product is not influenced, and the revolutionary transformation of the use of the steel product can be brought. Compared with the traditional anti-corrosion treatments such as painting, electroplating, chemical plating, surfacing and the like, the product can thoroughly solve the technical problem that the traditional anti-corrosion technology cannot be applied in a large scale and at low cost, can remarkably reduce the VOC emission of the existing heavy manufacturing industries such as machinery, ships, energy chemical industry and the like when carrying out the anti-corrosion coating on the surface of the product, and effectively solves the problem that the emission of the existing heavy manufacturing industries exceeds the standard in the aspect of equipment surface coating. The potential market for engineered structural steel sheets with corrosion resistant surfaces would be immeasurable from the annual costs of hundreds of millions of tons of engineered structural products and potentially several times the corrosion resistant costs of the products themselves. Disclosure of Invention The invention aims to overcome the defects of the prior art, and provides a coating-free carbon steel medium plate and a preparation method thereof, which solve the problem of easy corrosion of the existing carbon steel plate product in the processing and using and subsequent service processes by carrying out corrosion-resistant modification treatment on the surface of the carbon steel medium plate before leaving a factory. Meanwhile, the production of the product can reduce the procedures and emission problems in the downstream steel structure machining and manufacturing process, reduce the production cost, improve the production efficiency and reduce the emission of VOCs. In order to achieve the above purpose, the tech