Zinc-based alloy wire suitable for arc spraying and preparation method thereof

Abstract

The present invention relates to a zinc-based alloy wire suitable for arc spraying and a preparation method thereof. In a protective atmosphere, zinc and aluminum are melted in proportion to form a molten metal, and a zinc-aluminum alloy wire is obtained through processes such as cooling, aging treatment, and drawing. After surface treatment, a layer of pure copper and pure nickel is electroplated on the surface of the wire in succession, and finally a nickel-plated arc sprayed zinc-based alloy wire is obtained. The present invention electroplates nickel on the surface of the zinc-aluminum alloy wire through a certain process. After multiple studies and comparative verifications, the prepared alloy wire has a dense structure and a strong coating bonding force, which can meet the conditions for arc spraying. Compared with similar alloy wires, the alloy wire preparation cost of the present invention is greatly reduced, and the corrosion resistance of the arc spray coating is significantly improved.

Description

Technical Field

[0001] The invention relates to the field of arc spraying, and in particular to a zinc-based alloy wire suitable for arc spraying and a preparation method thereof. Background Art

[0002] The corrosion of metal structures has always caused great losses and harm to the national economy and people's lives in countries around the world, and has attracted much attention from countries around the world. With the continuous improvement of the service life of steel structure projects and the increasingly harsh outdoor corrosion environment, it is urgent to develop new and reliable thermal spray materials with longer corrosion protection life.

[0003] Nowadays, the materials used in arc spraying technology are mainly alloy powders or wires with Zn as the main component. The Zn element has good electrochemical properties. Obtaining a Zn coating on the surface of a general metal workpiece can effectively protect it from seawater corrosion, but the products produced after corrosion will cause the corrosion rate of the coating to increase, accelerating the corrosion consumption rate of the Zn coating. After adding Al elements to the Zn coating, the resulting Zn-Al alloy has good corrosion resistance and is suitable for surface protection of metal parts in a corrosive environment of humid salt spray atmosphere, but its corrosion resistance will be significantly reduced in high temperature or acidic environments. The nickel-based coating prepared by spraying nickel-based alloy wire has a dense coating and has the properties of resistance to high-temperature oxidation, heat shock and abrasion, but its high cost and low corrosion resistance at room temperature affect its application range. Summary of the invention

[0004] The purpose of the present invention is to provide a zinc-based alloy wire suitable for arc spraying and a preparation method thereof. The prepared zinc-based alloy wire is used for arc spraying to improve the corrosion resistance, stability and comprehensive mechanical properties of the coating.

[0005] To achieve the above purpose, the technical solution provided by the present invention is:

[0006] A method for preparing a zinc-based alloy wire suitable for arc spraying comprises the following steps:

[0007] Step (1): Under a protective atmosphere, zinc and aluminum are melted in proportion to form a molten metal;

[0008] Step (2): removing the gas dissolved in the molten metal;

[0009] Step (3): subjecting the molten metal after the dissolved gas is removed to heat preservation treatment to obtain a zinc-aluminum alloy liquid, and crystallizing the zinc-aluminum alloy liquid into a rough blank disc round material;

[0010] Step (4): performing a first annealing treatment on the rough blank disc material under a protective atmosphere; after the first annealing treatment, drawing is performed to obtain a zinc-aluminum alloy wire material, wherein a second annealing treatment is performed during the drawing process;

[0011] Step (5): performing surface treatment on the zinc-aluminum alloy wire, wherein the surface treatment includes pickling and electrolytic polishing to remove oil stains or oxides on the surface of the wire;

[0012] Step (6): electroplating a layer of pure copper on the surface of the surface-treated zinc-aluminum alloy wire to obtain a copper-plated wire, thereby improving the bonding strength between the coating and the substrate and improving the corrosion resistance of the coating;

[0013] Step (7): electroplating a layer of pure nickel on the surface of the copper-plated wire to obtain a zinc-aluminum-nickel-copper alloy wire, which is a zinc-based alloy wire suitable for arc spraying;

[0014] In zinc-aluminum-nickel-copper alloy wire, the mass percentage of elements is: zinc 70-85%, aluminum 10-15%, nickel 1-5%, copper 1-5%, and the rest are impurities.

[0015] To optimize the above technical solutions, the specific measures taken also include:

[0016] The protective atmosphere in step (1) and step (4) is argon gas, nitrogen gas or a mixture of the two.

[0017] The melting in step (1) is obtained by adding zinc ingots and aluminum ingots into a smelting furnace for melting, or by adding lump zinc into molten aluminum liquid, heating and melting and fully stirring. As a preferred solution, the melting temperature is 660-700°C and the stirring speed is 30-40r / min.

[0018] In step (2), the method for removing the gas dissolved in the molten metal is to pass nitrogen into the bottom of the molten metal through a steel pipe.

[0019] In step (3), the insulation treatment is carried out in an insulation furnace. As a preferred solution, the insulation time is 3-5 hours and the insulation temperature is 550-600°C.

[0020] In step (3), the rough blank disc round material is crystallized through a cylindrical crystallizer. As a preferred solution, the rough blank disc round material with a size of φ7.10-20.0 mm is crystallized, and the flow rate of cooling water during the crystallization process is 1000-1500 L / h.

[0021] In step (4), the first annealing treatment is an air cooling aging treatment in an annealing furnace. As a preferred solution, the aging treatment temperature is 200-220° C. and the aging treatment time is 3-5 hours.

[0022] In step (4), multiple drawing is performed by means of a wire reel and a wire drawing machine; as a preferred solution, during the drawing process, the lubricating oil concentration is 10-12% and the pulling speed is 5-50 mm / min.

[0023] In step (4), the second annealing treatment is an online dehydrogenation annealing using a pit-type annealing furnace at a treatment temperature of 180-200°C.

[0024] In step (5), the solvent used for pickling is a mixed solution of one or both of hydrochloric acid and sulfuric acid, and the solvent used for electrolytic polishing is a mixed solution of phosphoric acid, sulfuric acid and nitric acid.

[0025] In step (6), the electrolyte used for copper electroplating is a mixed solution of copper sulfate, copper chloride, sodium sulfate and potassium sulfate; as a preferred solution, the pH value of the electroplating solution used for copper electroplating is 6.5-7.5, and the electrolysis temperature is 40-45°C.

[0026] In step (7), the electrolyte used for nickel electroplating is a mixed solution of nickel sulfate, nickel acetate, hypophosphite, sodium borohydride, borane and hydrazine; as a preferred solution, the pH value of the electroplating solution used for nickel electroplating is 3.5-5.5, and the electrolysis temperature is 50-60°C.

[0027] As a preferred solution, the thickness of the electroplated pure copper on the surface of the zinc-aluminum alloy wire is 3-8 microns; the thickness of the electroplated pure nickel on the surface of the copper-plated wire is 5-20 microns.

[0028] The present invention also protects the zinc-based alloy wire prepared by the preparation method.

[0029] The zinc-based alloy wire has a bending and shelling angle greater than 120° and is suitable for arc spraying.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention provides a zinc-based alloy wire suitable for arc spraying and a preparation method thereof. By using the prepared zinc-aluminum alloy wire with copper and nickel layers electroplated on the surface for arc spraying, the bonding strength between the prepared spray coating and the substrate is improved by more than 50% compared with the traditional zinc-aluminum coating. At the same time, the addition of nickel can not only effectively improve the corrosion resistance of the coating, but more importantly, increase the wear resistance of the coating. Compared with the traditional zinc-aluminum coating, the corrosion resistance of the prepared coating is improved by about 25%, and the wear resistance is improved by about 10%.

[0032] The preparation method provided by the present invention is simple to operate, the conditions are easy to control, and the repeatability is good. Compared with the traditional zinc-aluminum alloy wire, the coating prepared using the new zinc-aluminum alloy wire has good wear resistance and corrosion resistance, has significant economic benefits, and can be used for actual production applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The present invention is a production process flow chart of the zinc-based alloy wire material.

[0034] Figure 2 This is a structural diagram of the zinc-aluminum-nickel-copper alloy wire produced in Example 1 of the present invention, wherein 1-zinc-aluminum alloy, 2-pure copper, and 3-pure nickel.

[0035] Figure 3 This is a cross-sectional energy spectrum diagram of the zinc-aluminum-nickel-copper alloy wire prepared in Example 1 of the present invention.

[0036] Figure 4 This is a comparison chart of the corrosion resistance of the zinc-aluminum-nickel-copper alloy wire produced in Example 1 of the present invention and the commonly used nickel-aluminum Ni95Al5 alloy wire and zinc-aluminum Zn85Al15 alloy wire on the market. DETAILED DESCRIPTION

[0037] The above contents of the present invention are further described in detail below in the form of embodiments, but this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the above contents of the present invention belong to the scope of the present invention.

[0038] The experimental methods used in the following examples are all conventional methods unless otherwise specified, and the reagents, methods and equipment used are all conventional reagents, methods and equipment in the technical field unless otherwise specified.

[0039] Example 1

[0040] A method for preparing a zinc-based alloy wire suitable for arc spraying comprises the following steps:

[0041] 1. In a nitrogen atmosphere, weigh zinc ingots and aluminum ingots at a weight ratio of 17:3, melt the aluminum ingots in a tongs boiler, and then add the zinc ingots. Use a steel pipe to pass nitrogen to the bottom of the molten metal to remove the gas dissolved in the alloy liquid.

[0042] 2. The molten metal is injected into a holding furnace for 3-5 hours of holding. After holding at 570°C, a zinc-aluminum alloy solution is obtained, which is crystallized into a φ7.5mm rough disk through a cylindrical crystallizer. The cooling water flow rate is 1000L / h.

[0043] 3. The blank is subjected to air cooling aging treatment at 200°C under argon protection for 5 hours.

[0044] 4. After secondary cooling, the wire is drawn by a wire drawing machine for 10-15 times to form a 2.0 mm zinc-aluminum alloy wire. During the drawing process, the lubricating oil concentration is 10-12% and the drawing speed is 30-50 mm / min.

[0045] 5. Under argon protection, perform secondary online dehydrogenation annealing at 180°C in a pit annealing furnace.

[0046] 6. Remove the oxide scale and rust on the surface of the wire by pickling, and remove the oil or oxide on the surface of the wire.

[0047] 7. Electroplate a layer of pure copper on the surface of the wire with a thickness of 5-8 microns to improve the bonding strength between the coating and the substrate and improve the corrosion resistance of the coating;

[0048] 8. Electroplate a layer of pure nickel on the surface of the copper-plated wire with a coating thickness of 10-20 microns to finally prepare a 2.0 mm zinc-aluminum-nickel-copper alloy wire.

[0049] Example 2

[0050] A method for preparing a zinc-based alloy wire suitable for arc spraying comprises the following steps:

[0051] 1. In an argon protective atmosphere, weigh zinc ingots and aluminum ingots at a weight ratio of 19:3, melt the aluminum ingots in a tongs boiler, and then add the zinc ingots. Use a steel pipe to pass nitrogen into the bottom of the molten metal to remove the gas dissolved in the alloy liquid.

[0052] 2. The molten metal is injected into a holding furnace for 3-5 hours of holding. After holding at 600°C, a zinc-aluminum alloy solution is obtained, which is crystallized into a φ18mm rough disk through a cylindrical crystallizer. The cooling water flow rate is 1500L / h.

[0053] 3. The blank is subjected to air cooling aging treatment at 220°C under argon protection for 4 hours.

[0054] 4. After secondary cooling, the wire is drawn by a wire drawing machine for 15-20 times to form a 1.2 mm zinc-aluminum alloy wire. During the drawing process, the lubricating oil concentration is 10-12% and the drawing speed is 20-30 mm / min.

[0055] 5. Under argon protection, carry out secondary online dehydrogenation annealing treatment at 200°C in a pit annealing furnace.

[0056] 6. Remove the oxide scale and rust on the surface of the wire by pickling, and remove the oil or oxide on the surface of the wire.

[0057] 7. Electroplate a layer of pure copper on the surface of the wire with a thickness of 3-5 microns to improve the bonding strength between the coating and the substrate and improve the corrosion resistance of the coating;

[0058] 8. Electroplate a layer of pure nickel on the surface of the copper-plated wire with a thickness of 5-10 microns to finally prepare a 1.2 mm zinc-aluminum-nickel-copper alloy wire.

[0059] The present invention uses a certain process to electroplate nickel on the surface of zinc-aluminum alloy wire. After multiple studies and comparative verifications, the prepared alloy wire has a dense structure and strong coating bonding, which meets the conditions for arc spraying. Compared with similar alloy wires, the wire preparation cost is greatly reduced, and the corrosion resistance of the arc spray coating is significantly improved.

[0060] The zinc-aluminum-nickel-copper wire prepared by this method has a bending and shelling angle greater than 120°, which meets the conditions for arc spraying. At the same time, compared with the common nickel-aluminum Ni95Al5 wire on the market, the corrosion resistance of the prepared wire is improved by 10-20 times without sealing, and the cost is reduced by 3-5 times. Compared with the common zinc-aluminum Zn85Al15 wire on the market, the corrosion resistance is improved by 10-20 times without sealing.

[0061] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any technician familiar with the profession, without departing from the scope of the technical solution of the present invention, according to the technical essence of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for preparing a zinc-based alloy wire suitable for arc spraying, characterized in that: The following steps are involved: Step (1): in a protective atmosphere, zinc and aluminum are melted in proportion to form a molten metal; Step (2): removing the gas dissolved in the molten metal; Step (3): subjecting the molten metal after the dissolved gas is removed to heat preservation treatment to obtain a zinc-aluminum alloy liquid, and crystallizing the zinc-aluminum alloy liquid into a rough blank disc round material; Step (4): subjecting the rough blank disc to a first annealing treatment in a protective atmosphere; after the first annealing treatment, drawing to obtain a zinc-aluminum alloy wire, wherein a second annealing treatment is performed during the drawing process; Step (5): performing surface treatment on the zinc-aluminum alloy wire, wherein the surface treatment comprises pickling and electrolytic polishing; Step (6): electroplating a layer of pure copper on the surface of the surface-treated zinc-aluminum alloy wire to obtain a copper-plated wire; Step (7): electroplating a layer of pure nickel on the surface of the copper-plated wire to obtain a zinc-aluminum-nickel-copper alloy wire, wherein the zinc-aluminum-nickel-copper alloy wire is a zinc-based alloy wire suitable for arc spraying; In zinc-aluminum-nickel-copper alloy wire, the mass percentage of elements is: zinc 70-85%, aluminum 10-15%, nickel 1-5%, copper 1-5%, and the rest is impurities; In step (4), the first annealing treatment is an aging treatment in an annealing furnace, followed by air cooling; wherein the aging treatment temperature is 200-220°C, and the aging treatment time is 3-5h; the second annealing treatment is an online dehydrogenation annealing in a pit annealing furnace, and the treatment temperature is 180-200°C; The thickness of the pure copper electroplated on the surface of the zinc-aluminum alloy wire is 3-8 microns; the thickness of the pure nickel electroplated on the surface of the copper-plated wire is 5-20 microns.

2. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: The protective atmosphere in step (1) and step (4) is argon, nitrogen or a mixture of the two.

3. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: The melting in step (1) is obtained by adding zinc ingots and aluminum ingots into a smelting furnace for melting, or by adding lump zinc into molten aluminum liquid, heating and melting, and fully stirring; wherein the heating and melting temperature is 660-700°C, and the stirring speed is 30-40 r / min.

4. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: In step (2), the method for removing the gas dissolved in the molten metal is to pass nitrogen into the bottom of the molten metal through a steel pipe.

5. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: In step (3), the insulation treatment is carried out in an insulation furnace, wherein the insulation time is 3-5 hours and the insulation temperature is 550-600°C.

6. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: In step (3), the rough blank disc round material is crystallized through a cylindrical crystallizer to form a rough blank disc round material with a size of φ7.10-20.0 mm. The flow rate of cooling water during the crystallization process is 1000-1500 L / h.

7. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: In step (4), multiple drawing is performed by means of a wire reel and a wire drawing machine; during the drawing process, the mass concentration of the lubricating oil is 10-12%, and the pulling speed is 5-50 mm / min.

8. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: In step (5), the solvent used for pickling is a mixed solution of one or both of hydrochloric acid and sulfuric acid, and the solvent used for electrolytic polishing is a mixed solution of phosphoric acid, sulfuric acid and nitric acid.

9. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: In step (6), the electrolyte used for copper electroplating is a mixed solution of copper sulfate, copper chloride, sodium sulfate and potassium sulfate; the pH value of the electroplating solution used for copper electroplating is 6.5-7.5, and the electrolysis temperature is 40-45°C.

10. The method for preparing a zinc-based alloy wire suitable for arc spraying according to claim 1, characterized in that: In step (7), the electrolyte used for nickel electroplating is a mixed solution of nickel sulfate, nickel acetate, hypophosphite, sodium borohydride, borane and hydrazine; the pH value of the electroplating solution used for nickel electroplating is 3.5-5.5, and the electrolysis temperature is 50-60°C.

11. The zinc-based alloy wire prepared by the preparation method according to any one of claims 1 to 10.

12. The zinc-based alloy wire according to claim 11, characterized in that: The zinc-based alloy wire has a bending and shelling angle greater than 120° and is suitable for arc spraying.

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