High-Si cold-rolled steel sheet with high corrosion resistance

Abstract

The invention relates to the technical field of alloy, in particular to a high-Si cold-rolled steel sheet with high corrosion resistance, which comprises a base plate and a protection structure, the protection structure comprises a zinc-iron alloy layer, a high-molecular polymerization adhesive film, an aluminum-zinc alloy layer and an anti-corrosion layer; the base plate is an existing high-Si cold-rolled steel plate, the protection structure is used for protecting the base plate, the base plate is coated with the zinc-iron alloy layer, and the surface of the zinc-iron alloy layer is coated with the macromolecule adhesive film, so that a layer of waterproof and anti-cracking passivation structure is formed in the machining process, and the overall corrosion resistance is improved; the aluminum-zinc alloy layer is coated on the surface of the macromolecular adhesive film, embrittlement in a high-temperature state is avoided, the use field of the plate is expanded, the anti-corrosion layer is resistant to corrosion and high temperature and has good corrosion resistance, the overall corrosion resistance is improved, the base plate is protected, and the service life of the plate is prolonged. Therefore, the problems that an existing high-Si cold-rolled steel plate is poor in corrosion resistance and high in corrosion resistance cost are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of alloys, and in particular to a high-Si cold-rolled steel plate with strong corrosion resistance. Background Art

[0002] Cold rolling uses hot-rolled coil as raw material and is rolled below the recrystallization temperature at room temperature. Cold-rolled steel plate is the steel plate produced by the cold rolling process.

[0003] In order to improve the strength of the cold-rolled steel sheets in the existing technology, Si is generally added thereto. High-Si cold-rolled steel sheets are widely used in the field of automobile manufacturing. In order to improve the corrosion resistance of the existing high-Si cold-rolled steel sheets, an anti-corrosion protective layer is generally added to the surface.

[0004] However, the corrosion resistance of existing high-Si cold-rolled steel sheets with added anti-corrosion protective layers is still poor, and the cost of corrosion resistance is high. Summary of the Invention

[0005] The purpose of the present invention is to provide a high-Si cold-rolled steel plate with strong corrosion resistance, aiming to solve the problems of poor corrosion resistance and high corrosion resistance cost of existing high-Si cold-rolled steel plates.

[0006] To achieve the above-mentioned objectives, the present invention provides a high-Si cold-rolled steel plate with strong corrosion resistance, comprising a substrate and a protective structure; the protective structure comprises a zinc-iron alloy layer, a polymer adhesive film, an aluminum-zinc alloy layer and an anti-corrosion layer; the zinc-iron alloy layer is fixedly connected to the substrate and is located on one side of the substrate, the polymer adhesive film is fixedly connected to the zinc-iron alloy layer and is located on the side of the zinc-iron alloy layer away from the substrate, the aluminum-zinc alloy layer is fixedly connected to the polymer adhesive film and is located on the side of the polymer adhesive film away from the zinc-iron alloy layer, and the anti-corrosion layer is fixedly connected to the aluminum-zinc alloy layer and is located on the side of the aluminum-zinc alloy layer away from the polymer adhesive film.

[0007] Wherein, the protection structure further includes a passivation layer, which is fixedly connected to the anti-corrosion layer and is located on a side of the anti-corrosion layer away from the aluminum-zinc alloy layer.

[0008] Wherein, the protection structure further includes an impact-resistant coating, which is fixedly connected to the passivation layer and is located on a side of the passivation layer away from the anti-corrosion layer.

[0009] In which, the protective structure also includes a titanium plate layer and an insulating coating layer. The titanium plate layer is fixedly connected to the impact-resistant coating and is located on the side of the impact-resistant coating away from the passivation layer. The insulating coating layer is fixedly connected to the titanium plate layer and is located on the side of the titanium plate layer away from the impact-resistant coating.

[0010] In which, the protective structure also includes a high-bonding coating and an anti-oxidation coating. The high-bonding coating is fixedly connected to the insulating coating layer and is located on the side of the insulating coating layer away from the titanium plate layer. The anti-oxidation coating is fixedly connected to the high-bonding coating and is located on the side of the high-bonding coating away from the insulating coating layer.

[0011] In which, the protective structure also includes a waterproof coating, a first thermal insulation layer and a fire retardant coating. The waterproof coating is fixedly connected to the antioxidant coating and is located on the side of the antioxidant coating away from the high adhesion coating. The first thermal insulation layer is fixedly connected to the waterproof coating and is located on the side of the waterproof coating away from the antioxidant coating. The fire retardant coating is fixedly connected to the first thermal insulation layer and is located on the side of the first thermal insulation layer away from the waterproof coating.

[0012] Wherein, the substrate is composed of the following components:

[0013] Distribution by mass: C: 0.3%, Si: 3.0%, Mn: 3.0%, P: less than 0.1%, S: less than 0.05%, Al: 1%, N: less than 0.01%, and the balance is Fe and inevitable impurities.

[0014] The present invention provides a high-Si cold-rolled steel plate with strong corrosion resistance. The substrate is an existing high-Si cold-rolled steel plate. The protective structure is used to protect the substrate. A zinc-iron alloy layer is coated on the substrate. The polymer adhesive film is coated on the surface of the zinc-iron alloy layer, so that a waterproof and crack-resistant passivation structure is formed during the processing, thereby improving the overall corrosion resistance. An aluminum-zinc alloy layer is further coated on the surface of the polymer adhesive film to avoid embrittlement under high temperature conditions, thereby expanding the use field of the plate. The anti-corrosion layer is not only corrosion-resistant but also high-temperature resistant. The raw materials of the anti-corrosion layer are silicone, modified silicone resin, talcum powder, mica powder, zinc phosphate, zinc molybdate, n-butanol, coupling agent, silicon dioxide and octanoate, which has good corrosion resistance, improves the overall corrosion resistance, and protects the substrate, thereby solving the problems of poor corrosion resistance and high corrosion resistance cost of existing high-Si cold-rolled steel plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1This is a cross-sectional view of the entirety of a high-Si cold-rolled steel plate with strong corrosion resistance provided by the present invention.

[0017] Figure 2 yes Figure 1 A partial enlargement of detail A.

[0018] In the figure: 101-substrate, 102-protective structure, 103-zinc-iron alloy layer, 104-polymer adhesive film, 105-aluminum-zinc alloy layer, 106-corrosion protection layer, 107-passivation layer, 108-impact-resistant coating, 109-titanium plate layer, 110-insulating coating layer, 111-high-adhesion coating, 112-anti-oxidation coating, 113-waterproof coating, 114-first thermal insulation layer, 115-fireproof coating, 116-second thermal insulation layer, 117-tin layer, 118-high-temperature resistant layer, 119-lithium silicate coating layer, 120-wear-resistant layer. DETAILED DESCRIPTION

[0019] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0020] See also Figures 1 to 2 The present invention provides a high-Si cold-rolled steel sheet with strong corrosion resistance:

[0021] It includes a substrate 101 and a protective structure 102; the protective structure 102 includes a zinc-iron alloy layer 103, a polymer adhesive film 104, an aluminum-zinc alloy layer 105 and an anti-corrosion layer 106; the zinc-iron alloy layer 103 is fixedly connected to the substrate 101 and is located on one side of the substrate 101, the polymer adhesive film 104 is fixedly connected to the zinc-iron alloy layer 103 and is located on the side of the zinc-iron alloy layer 103 away from the substrate 101, the aluminum-zinc alloy layer 105 is fixedly connected to the polymer adhesive film 104 and is located on the side of the polymer adhesive film 104 away from the zinc-iron alloy layer 103, and the anti-corrosion layer 106 is fixedly connected to the aluminum-zinc alloy layer 105 and is located on the side of the aluminum-zinc alloy layer 105 away from the polymer adhesive film 104.

[0022] In this embodiment, the substrate 101 is an existing high-Si cold-rolled steel plate, and the protective structure 102 is used to protect the substrate 101. A zinc-iron alloy layer 103 is coated on the substrate 101, and the surface of the zinc-iron alloy layer 103 is coated with the polymer adhesive film, so that a layer of waterproof and crack-resistant passivation structure is formed during the processing, thereby improving the overall corrosion resistance. A layer of aluminum-zinc alloy layer 105 is further coated on the surface of the polymer adhesive film to avoid embrittlement under high temperature conditions, thereby expanding the use field of the plate. The anti-corrosion layer 106 is not only anti-corrosion, but also high-temperature resistant. The raw material of the anti-corrosion layer 106 is silicone. , modified silicone resin, talcum powder, mica powder, zinc phosphate, zinc molybdate, n-butanol, coupling agent, silica and octanoate, with good corrosion resistance, improving the overall corrosion resistance, protecting the substrate 101, thereby solving the problems of poor corrosion resistance and high corrosion resistance cost of existing high-Si cold-rolled steel plates; it should be noted that the thickness of the zinc-iron alloy layer 103 is 500-800μm, the thickness of the polymer adhesive film 104 is 400-500μm, the thickness of the aluminum-zinc alloy layer 105 is 200-500μm; the thickness of the anti-corrosion layer 106 is 350-500μm.

[0023] Furthermore, the protection structure 102 further includes a passivation layer 107 , which is fixedly connected to the anti-corrosion layer 106 and is located on a side of the anti-corrosion layer 106 away from the aluminum-zinc alloy layer 105 .

[0024] In this embodiment, the passivation layer 107 is used to protect the anti-corrosion layer 106 to prevent the anti-corrosion layer 106 from being oxidized and reducing its anti-corrosion function. The thickness of the passivation layer 107 is 1-10 nm.

[0025] Furthermore, the protection structure 102 further includes an impact-resistant coating 108 . The impact-resistant coating 108 is fixedly connected to the passivation layer 107 and is located on a side of the passivation layer 107 away from the anti-corrosion layer 106 .

[0026] In this embodiment, the impact-resistant coating 108 is used to reduce the impact on the anti-corrosion layer 106 and extend the service life of the anti-corrosion layer 106. The thickness of the impact-resistant coating 108 is 8-20 μm.

[0027] Furthermore, the protective structure 102 also includes a titanium plate layer 109 and an insulating coating layer 110. The titanium plate layer 109 is fixedly connected to the impact-resistant coating 108 and is located on the side of the impact-resistant coating 108 away from the passivation layer 107. The insulating coating layer 110 is fixedly connected to the titanium plate layer 109 and is located on the side of the titanium plate layer 109 away from the impact-resistant coating 108.

[0028] In this embodiment, the titanium plate layer 109 has a relatively low hardness and requires buffering protection during cold rolling. After cold rolling, the insulating coating layer 110 is coated on the titanium plate layer 109 for insulation. The thickness of the titanium plate layer 109 is 1.5 mm, and the thickness of the insulating coating layer 110 is 2-7 μm.

[0029] Furthermore, the protective structure 102 also includes a high-bonding coating 111 and an anti-oxidation coating 112. The high-bonding coating 111 is fixedly connected to the insulating coating layer 110 and is located on the side of the insulating coating layer 110 away from the titanium plate layer 109. The anti-oxidation coating 112 is fixedly connected to the high-bonding coating 111 and is located on the side of the high-bonding coating 111 away from the insulating coating layer 110.

[0030] In this embodiment, the high-bonding coating 111 is used to enhance the coating strength of the anti-oxidation coating 112, and the anti-oxidation coating 112 is used to further prevent internal structural oxidation. The thickness of the high-bonding coating 111 is 50-150 μm; the thickness of the anti-oxidation coating 112 is 300 μm.

[0031] Furthermore, the protective structure 102 also includes a waterproof coating 113, a first thermal insulation layer 114 and a fire retardant coating 115. The waterproof coating 113 is fixedly connected to the antioxidant coating 112 and is located on the side of the antioxidant coating 112 away from the high adhesion coating 111. The first thermal insulation layer 114 is fixedly connected to the waterproof coating 113 and is located on the side of the waterproof coating 113 away from the antioxidant coating 112. The fire retardant coating 115 is fixedly connected to the first thermal insulation layer 114 and is located on the side of the first thermal insulation layer 114 away from the waterproof coating 113.

[0032] In this embodiment, the waterproof coating 113 is used to prevent water erosion, the first thermal insulation layer 114 is used to isolate external heat to prevent it from affecting the service life of the internal coating, and the fire retardant coating 115 is used to prevent fire. The thickness of the waterproof coating 113 is 50-120 μm; the thickness of the first thermal insulation layer 114 is 10-50 nm; and the thickness of the fire retardant coating 115 is 0.5-1 mm.

[0033] Furthermore, the substrate 101 is composed of the following components:

[0034] Distribution by mass: C: 0.3%, Si: 3.0%, Mn: 3.0%, P: less than 0.1%, S: less than 0.05%, Al: 1%, N: less than 0.01%, and the balance is Fe and inevitable impurities.

[0035] In this embodiment, the cold-rolled steel sheet is heated using a direct-fire burner with an air ratio of 0.7 to 0.89 to a temperature range of 300°C to below Ta°C during heating; then heated using a direct-fire burner with an air ratio of 0.95 to a temperature range of Ta°C to below Tb°C; and then soaked annealed in a furnace with a dew point of -25°C or below and a gas composition of 1 to 10% by volume H2 and the balance N2. The direct-fire burner oxidizes Fe on the surface of the cold-rolled steel sheet and subsequently reduces it to oxidize Si within the cold-rolled steel sheet. This allows for the production of a high-Si cold-rolled steel sheet containing 0.6% or more Si, while improving chemical conversion treatability and achieving a tensile strength of 590 MPa or above, a TS×EL of 18,000 MPa·% or above, and excellent workability.

[0036] Furthermore, the protective structure 102 also includes a second thermal insulation layer 116 and a tin layer 117. The second thermal insulation layer 116 is fixedly connected to the fire retardant coating 115 and is located on the side of the fire retardant coating 115 away from the first thermal insulation layer 114. The tin layer 117 is fixedly connected to the second thermal insulation layer 116 and is located on the side of the second thermal insulation layer 116 away from the fire retardant coating 115.

[0037] In this embodiment, the second thermal insulation layer 116 is used for further thermal insulation, and the tin layer 117 has rust and corrosion resistance, further enhancing the overall corrosion resistance. The thickness of the second thermal insulation layer 116 is 10-50nm, and the thickness of the tin layer 117 is 0.5-0.8mm.

[0038] Furthermore, the protective structure 102 also includes a high-temperature resistant layer 118, a lithium silicate coating layer 119 and a wear-resistant layer 120. The high-temperature resistant layer 118 is fixedly connected to the tin layer 117 and is located on the side of the tin layer 117 away from the second thermal insulation layer 116. The lithium silicate coating layer 119 is fixedly connected to the high-temperature resistant layer 118 and is located on the side of the high-temperature resistant layer 118 away from the tin layer 117. The wear-resistant layer 120 is fixedly connected to the lithium silicate coating layer 119 and is located on the side of the lithium silicate coating layer 119 away from the high-temperature resistant layer 118.

[0039] In this embodiment, a high-temperature resistant coating is applied to the surface of the tin layer 117 by roller coating and then calcined and cured to form the high-temperature resistant layer 118. The lithium silicate coating layer 119 prevents the sharp increase in wear of the cold press, thereby improving the overall die bite resistance. The wear-resistant layer 120 is used to improve the overall wear resistance. The thickness of the high-temperature resistant layer 118 is 50-120 μm, the thickness of the lithium silicate coating layer 119 is 40-50 μm, and the thickness of the wear-resistant layer 120 is 0.07-1 mm.

[0040] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of the rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A high-Si cold-rolled steel sheet with strong corrosion resistance, characterized in that: It includes a substrate and a protective structure; the protective structure includes a zinc-iron alloy layer, a high molecular polymer adhesive film, an aluminum-zinc alloy layer and an anti-corrosion layer; the zinc-iron alloy layer is fixedly connected to the substrate and is located on one side of the substrate, the high molecular polymer adhesive film is fixedly connected to the zinc-iron alloy layer and is located on the side of the zinc-iron alloy layer away from the substrate, the aluminum-zinc alloy layer is fixedly connected to the high molecular polymer adhesive film and is located on the side of the high molecular polymer adhesive film away from the zinc-iron alloy layer, and the anti-corrosion layer is fixedly connected to the aluminum-zinc alloy layer and is located on the side of the aluminum-zinc alloy layer away from the high molecular polymer adhesive film.

2. The high-Si cold-rolled steel sheet with strong corrosion resistance according to claim 1, characterized in that: The protection structure further includes a passivation layer, which is fixedly connected to the anti-corrosion layer and is located on a side of the anti-corrosion layer away from the aluminum-zinc alloy layer.

3. The high-Si cold-rolled steel sheet with strong corrosion resistance according to claim 2, characterized in that: The protection structure further comprises an impact-resistant coating, which is fixedly connected to the passivation layer and is located on a side of the passivation layer away from the anti-corrosion layer.

4. The high-Si cold-rolled steel sheet with strong corrosion resistance according to claim 3, characterized in that: The protective structure also includes a titanium plate layer and an insulating coating layer. The titanium plate layer is fixedly connected to the impact-resistant coating and is located on the side of the impact-resistant coating away from the passivation layer. The insulating coating layer is fixedly connected to the titanium plate layer and is located on the side of the titanium plate layer away from the impact-resistant coating.

5. The high-Si cold-rolled steel sheet with strong corrosion resistance according to claim 4, characterized in that: The protective structure also includes a high-bonding coating and an anti-oxidation coating. The high-bonding coating is fixedly connected to the insulating coating layer and is located on the side of the insulating coating layer away from the titanium plate layer. The anti-oxidation coating is fixedly connected to the high-bonding coating and is located on the side of the high-bonding coating away from the insulating coating layer.

6. The high-Si cold-rolled steel sheet with strong corrosion resistance according to claim 5, characterized in that: The protective structure also includes a waterproof coating, a first thermal insulation layer and a fire retardant coating. The waterproof coating is fixedly connected to the anti-oxidation coating and is located on the side of the anti-oxidation coating away from the high adhesion coating. The first thermal insulation layer is fixedly connected to the waterproof coating and is located on the side of the waterproof coating away from the anti-oxidation coating. The fire retardant coating is fixedly connected to the first thermal insulation layer and is located on the side of the first thermal insulation layer away from the waterproof coating.

7. The high-Si cold-rolled steel sheet with strong corrosion resistance according to claim 6, characterized in that: The substrate is composed of the following components: Distribution by mass: C: 0.3%, Si: 3.0%, Mn: 3.0%, P: less than 0.1%, S: less than 0.05%, Al: 1%, N: less than 0.01%, and the balance is Fe and inevitable impurities.

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