Search

CN-121975366-A - Corrosion-resistant layer of steel structure and manufacturing method thereof

CN121975366ACN 121975366 ACN121975366 ACN 121975366ACN-121975366-A

Abstract

The invention discloses a corrosion-resistant layer of a steel structure and a manufacturing method thereof, and belongs to the technical field of steel structure protection. The corrosion-resistant layer sequentially comprises a modified epoxy zinc-rich toughening primer layer, a functional epoxy cloud iron intermediate paint layer and a graphene-elastomer composite finish paint layer from inside to outside, and adopts a synergistic design of toughening, impact resistance, strong adhesion, anti-drop and efficient corrosion resistance. The manufacturing method comprises the steps of substrate pretreatment, high-pressure airless spraying and sectional curing of each coating, and the combination and the protection performance of the coating are enhanced through ingredient optimization and process cooperation. The invention effectively solves the problems of easy cracking, easy layering and falling and unbalanced performance of the traditional coating, realizes the cooperative promotion of impact resistance, adhesive force and corrosion resistance, and is suitable for protecting steel structures in severe environments such as railway bridges, ocean platforms and the like.

Inventors

  • WU JINGLIANG
  • LI CHANG
  • WU ZHENBO

Assignees

  • 海南华金钢构有限公司

Dates

Publication Date
20260505
Application Date
20260212

Claims (8)

  1. 1. The corrosion-resistant layer of the steel structure is characterized by sequentially comprising a primer layer, an intermediate paint layer and a finish paint layer from inside to outside; The primer layer comprises a resin matrix, zinc powder, an elastomer component and a self-repairing functional component; The intermediate paint layer comprises a resin matrix, a flaky antirust filler, a modified carbon material and a curing system; The topcoat layer comprises a resin matrix, graphene, and an elastomer modifying component.
  2. 2. The corrosion resistant layer of a steel structure according to claim 1, wherein the resin matrix of the primer layer is an epoxy resin, the elastomer component is a core-shell acrylic-butadiene elastomer microsphere, the self-repairing functional component is a self-repairing microcapsule, and the primer layer further comprises a phosphorus iron powder, a coupling agent and fumed silica; The resin matrix of the intermediate paint layer is bisphenol A epoxy resin, the flaky antirust filler is mica ferric oxide, the modified carbon material is 4-methyl-5- (1-naphthyl) -2-aminothiazole modified graphene oxide, the curing system comprises a polyether amine curing agent, and the intermediate paint layer also comprises glass flakes and a carbamate grafting modifier; the resin matrix of the finish paint layer is high-hydroxyl acrylic polyurethane resin, the elastomer modification component is polysiloxane modified acrylic elastomer, and the finish paint layer further comprises titanium white, an ultraviolet absorber, an antioxidant and a substrate wetting agent.
  3. 3. The corrosion resistant layer of a steel structure according to claim 2, wherein in the primer layer, the mass fraction of epoxy resin is 50% -60%, the mass fraction of zinc powder is 70% -80% by weight, the mass fraction of elastomer component is 3% -8% by weight, the mass fraction of self-repairing functional component is 5% -10% by weight, in the intermediate layer, the mass fraction of bisphenol A epoxy resin is 40% -50% by weight, the mass fraction of mica iron oxide is 30% -45% by weight, the mass fraction of modified carbon material is 2% -5% by weight, the mass ratio of polyether amine curing agent to epoxy resin is 1:3, the mass fraction of high-hydroxyl acrylic polyurethane resin is 55% -65% by weight, the mass fraction of graphene is 1% -3% by weight, and the mass fraction of elastomer modifying component is 8% -12% by weight.
  4. 4. A method for manufacturing the steel structure corrosion resistant layer according to any one of claims 1 to 3, comprising the steps of: Step one, preprocessing a substrate, sequentially carrying out sand blasting treatment, chemical cleaning and silane coupling agent treatment to form a substrate-coating combination foundation; Preparing and coating a coating, namely sequentially preparing and coating a primer layer, an intermediate paint layer and a top paint layer by adopting a high-pressure airless spraying mode; step three, sectional solidification, namely carrying out gradient temperature solidification and room temperature placement on each coated coating respectively, and reducing internal stress.
  5. 5. The method according to claim 4, wherein in the first step, the sand blasting is performed to Sa3.0 level, the surface roughness Ra=60-100 μm is controlled, the chemical cleaning is sequentially alkali cleaning, water cleaning, acid cleaning, water cleaning and drying, wherein the alkali cleaning is performed by using a 5% sodium hydroxide solution, the temperature is 20-30 ℃ for 10-15 min, the acid cleaning is performed by using a 1% hydrochloric acid solution, the temperature is 20-30 ℃ for 5-8 min, the drying temperature is 80-100 ℃ and the time is 30-40 min, the silane coupling agent is gamma-aminopropyl triethoxysilane, the silane coupling agent is sprayed by using an ethanol solution with the mass fraction of 1% -2%, and the silane coupling agent is dried by air drying at room temperature for 5-10 min after sand blasting and drying.
  6. 6. The method according to claim 4, wherein in the second step, the primer layer is prepared by mixing and stirring epoxy resin and resin diluent according to a mass ratio of 10:1, adding a dispersing wetting agent, a defoaming agent and a thickening agent, and continuing stirring to obtain a resin mixture; sequentially adding zinc powder, ferrophosphorus powder, an anti-settling agent, glass beads and a coupling agent after adjusting the rotating speed, and stirring to prepare a film forming component; Mixing a curing agent and a curing diluent according to a mass ratio of 8:1, adding a flash rust inhibitor, and stirring to obtain a curing component; mixing a film forming component, a curing component and self-repairing microcapsules according to a mass ratio of 100:30:8, adding fumed silica and a defoaming agent, and stirring to prepare a primer; coating for 2-3 times, wherein the thickness of each dry film is 40-60 mu m, the two times are separated by 2-4 hours.
  7. 7. The manufacturing method of the intermediate paint layer, according to claim 6, is characterized in that the preparation of the intermediate paint layer comprises the steps of stirring the modified graphene oxide and the carbamate grafting modifier for 3-5 hours at room temperature to obtain the functionalized modified graphene oxide; Mixing bisphenol A epoxy resin and a dispersing agent, adding functional modified graphene oxide, continuously stirring, sequentially adding cosolvent, glass flakes and mica iron oxide after rotating down, and then adding a curing agent compound system, and stirring to prepare an intermediate paint; the method comprises the steps of spraying once during coating, wherein the thickness of a wet film is 300-380 mu m, and coating a finish paint layer within 30 minutes after surface drying, wherein the preparation of the finish paint layer comprises the following steps: Dispersing graphene in ethanol, performing ultrasonic dispersion, adding triethylamine, performing ice bath preservation to obtain graphene dispersion liquid, mixing and stirring high-hydroxy acrylic polyurethane resin and polysiloxane modified acrylic elastomer, adding hydroxy acrylic dispersion, and continuously stirring; And mixing and grinding deionized water, a dispersing agent and titanium dioxide, adding the resin system, adding graphene dispersion liquid, a weather-resistant auxiliary agent and a substrate wetting agent, and stirring to obtain the finish paint, wherein the thickness of a wet film is 80-90 mu m during coating.
  8. 8. The manufacturing method of the composite material of the three-step coating is characterized in that in the third step, the sectional curing is specifically carried out after the primer layer is coated, the temperature is 60 ℃ for pre-curing for 30min, the room temperature is set for 1h, the temperature is 80 ℃ for curing 1h, the temperature is set for 1h, the temperature is 100 ℃ for curing 2h, the temperature is set for 24h, the raw material stirring speed is 300-180 rpm, the stirring time is 10-150 min, and the adding interval of adjacent solid raw materials is not less than 20min in the preparation process of each coating.

Description

Corrosion-resistant layer of steel structure and manufacturing method thereof Technical Field The invention relates to the technical field of steel structure protection, in particular to a corrosion-resistant layer of a steel structure and a manufacturing method thereof. Background The steel structure is widely applied to the fields of construction, traffic, ocean engineering and the like due to the advantages of high strength, convenient construction and the like, but is easy to generate corrosion failure in severe environments such as humidity, salt fog, acid-base medium and the like, so that the structural strength is reduced, the service life is shortened, and even safety accidents are caused. The existing steel structure anti-corrosion coating adopts a 'primer and finish paint' double-layer structure or a single anti-corrosion coating, and has the following technical defects: The traditional coating has high brittleness, is easy to crack and fall off when being impacted by external force, and cannot adapt to the scenes such as railway bridge vibration, ocean platform wind wave impact and the like; The bonding reliability is poor, the bonding between the coating and the base material and between the coating and the layers is dependent on physical adsorption, and the coating is easy to fall off in a layered manner after long-term use, so that the corrosion-resistant system is invalid. Therefore, developing a corrosion-resistant layer with synergistic optimization of toughening, impact resistance, strong bonding, anti-drop and efficient corrosion resistance becomes a key for solving the severe environmental protection problem of the steel structure. Disclosure of Invention The invention aims to provide a corrosion-resistant layer of a steel structure and a manufacturing method thereof, which are used for solving the problems of insufficient impact resistance and poor bonding reliability in the prior art. The technical scheme for solving the technical problems is as follows: The utility model provides a corrosion-resistant layer of steel construction, includes primer layer, intermediate paint layer and finish paint layer from inside to outside in proper order, the primer layer contains resin matrix, zinc powder, elastomer component and self-repairing functional component, the intermediate paint layer contains resin matrix, slice rust-resistant filler, modified carbon material and curing system, the finish paint layer contains resin matrix, graphite alkene and elastomer modified component, through "toughened shock resistance + strong bonding anti-drop + high-efficient anticorrosive" collaborative design, realizes the collaborative promotion of impact resistance, adhesive force and corrosion resistance, is applicable to the steel construction protection under the harsh environment. The paint comprises a primer layer, a middle paint layer, a resin matrix, a modified carbon material, a curing system and an elastic component, wherein the resin matrix of the primer layer is epoxy resin, the elastomer component is acrylic acid-butadiene elastomer microspheres with a core-shell structure, the self-repairing functional component is self-repairing microcapsules, the primer layer further comprises phosphorus iron powder, a coupling agent and fumed silica, the resin matrix of the middle paint layer is bisphenol A epoxy resin, a flaky antirust filler is mica iron oxide, the modified carbon material is 4-methyl-5- (1-naphthyl) -2-aminothiazole modified graphene oxide, the curing system comprises a polyether amine curing agent, the middle paint layer further comprises glass flakes and a carbamate grafting modifier, the resin matrix of the top paint layer is high-hydroxyl acrylic polyurethane resin, the elastomer modifying component is polysiloxane modified acrylic elastomer, and the top paint layer further comprises titanium pigment, an ultraviolet absorber, an antioxidant and a substrate wetting agent. According to the further scheme, in the primer layer, the mass fraction of epoxy resin is 50% -60%, the mass fraction of zinc powder is 70% -80% by weight based on the solid content of the primer, the mass fraction of elastomer component is 3% -8% by weight, the mass fraction of self-repairing functional component is 5% -10% by weight, in the intermediate paint layer, the mass fraction of bisphenol A epoxy resin is 40% -50% by weight, the mass fraction of mica iron oxide is 30% -45% by weight, the mass fraction of modified carbon material is 2% -5% by weight, the mass ratio of polyether amine curing agent to epoxy resin is 1:3, the mass fraction of high-hydroxyl acrylic polyurethane resin is 55% -65% by weight, the mass fraction of graphene is 1% -3% by weight, and the mass fraction of elastomer modified component is 8% -12% by weight. The thickness of the primer layer is 120-160 mu m, the thickness of the intermediate paint layer is 250-300 mu m, and the thickness of the finish paint layer is 70-80 mu m. The self-repairi