A self-shielded flux-cored wire and a method of manufacturing the same

Abstract

The application provides a self-protection flux-cored wire and a preparation process thereof, and relates to the technical field of welding materials. The self-protection flux-cored wire comprises a steel belt sheath, a flux material and a fluorinated graphene coating. The flux material is filled in the steel belt sheath, and the fluorinated graphene coating is coated on the outer surface of the steel belt sheath. The flux material comprises the following raw materials in terms of mass percentage: 30-50% of atomized iron powder, 18-35% of barium fluoride, 10-20% of aluminum-magnesium alloy, 10-20% of aluminum powder, 3-8% of metallic manganese, 2-5% of silicon iron, 1-3% of silicon-calcium alloy, 2-5% of wollastonite, 1-3% of fluorite, 0.5-2% of potassium fluosilicate, 1-5% of lithium fluoride and 1-3% of nickel powder. The self-protection flux-cored wire can be used for all-position welding without gas protection, has low porosity sensitivity, and the fluorinated graphene coating can effectively prevent the invasion of moisture in the air, so that the self-protection flux-cored wire is easier to store without affecting the welding performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of welding material, in particular to a self-shielded flux-cored wire and a preparation method thereof. BACKGROUND

[0002] As a kind of efficient and suitable for outdoor operation welding material, self-shielded flux-cored wire often needs flexible and reliable welding technology to complete in our daily life and industrial production and manufacturing steel structure.

[0003] Compared with gas shielded wire, self-shielded flux-cored wire has better wind resistance, and small size wire can be made to 0.8mm, and at the same time, self-shielded flux-cored wire can be welded at a wind speed of 8m / s without any protective gas, and still can guarantee good performance.

[0004] In application, self-shielded flux-cored wire has good adaptability and simple operation, and is widely used in high-rise buildings, bridges, offshore oil platforms, pipelines and other fields. However, the wire is prone to moisture during storage, resulting in unstable mechanical properties of the welding position and low deposition efficiency during welding. SUMMARY

[0005] In view of the above shortcomings of the prior art, the present application provides a self-shielded flux-cored wire and a preparation method thereof to improve the technical problem that the existing self-shielded flux-cored wire is prone to moisture and affects the welding performance.

[0006] To achieve the above object and other related objects, the present application provides a self-shielded flux-cored wire, comprising a steel belt outer skin, a core material and a fluorinated graphene coating, the core material is filled in the steel belt outer skin, and the fluorinated graphene coating is coated on the outer surface of the steel belt outer skin, the core material comprises the following mass percentages of raw materials based on the total mass of the core material: 30-50% of atomized iron powder, 18-35% of barium fluoride, 10-20% of aluminum-magnesium alloy, 10-20% of aluminum powder, 3-8% of metallic manganese, 2-5% of silicon iron, 1-3% of silicon-calcium alloy, 2-5% of wollastonite, 1-3% of fluorite, 0.5-2% of potassium fluorosilicate, 1-5% of lithium fluoride and 1-3% of nickel powder.

[0007] In an example of the self-shielded flux-cored wire of the present application, the atomized iron powder is added in an amount of 32-43%.

[0008] In an example of the self-shielded flux-cored wire of the present application, the barium fluoride is added in an amount of 19-28%.

[0009] In an example of the self-shielded flux-cored wire of the present application, the aluminum-magnesium alloy is added in an amount of 12-20%.

[0010] In an example of the self-shielded flux-cored wire of the present application, the aluminum powder is added in an amount of 11-15%.

[0011] In an example of the self-shielded flux-cored wire of the present invention, the metallic manganese is added in an amount of 4-6%.

[0012] In an example of the self-shielded flux-cored wire of the present invention, the silicon-calcium alloy is added in an amount of 2-3%.

[0013] In an example of the self-shielded flux-cored wire of the present invention, the fluorite is added in an amount of 1.5-3%.

[0014] In an example of the self-shielded flux-cored wire of the present invention, the lithium fluoride is added in an amount of 2.5-5%.

[0015] In an example of the self-shielded flux-cored wire of the present invention, the nickel powder is added in an amount of 1.5-3%.

[0016] In an example of the self-shielded flux-cored wire of the present invention, the fluorinated graphene used to prepare the fluorinated graphene coating has a particle size of 1-5 μm.

[0017] In an example of the self-shielded flux-cored wire of the present invention, the aluminum content in the aluminum-magnesium alloy is 50±3%, and the magnesium content is greater than or equal to 47%.

[0018] In an example of the self-shielded flux-cored wire of the present invention, the calcium content in the silicon-calcium alloy is greater than or equal to 28%, and the silicon content is greater than or equal to 55%.

[0019] In an example of the self-shielded flux-cored wire of the present invention, the content of SiO2 in the wollastonite is greater than or equal to 45%, and the content of CaO is greater than or equal to 40%.

[0020] In an example of the self-shielded flux-cored wire of the present invention, the atomized iron powder has a particle size of 60-80 mesh.

[0021] In an example of the self-shielded flux-cored wire of the present invention, the barium fluoride has a particle size of 60-80 mesh.

[0022] In an example of the self-shielded flux-cored wire of the present invention, the aluminum-magnesium alloy has a particle size of 60-80 mesh.

[0023] In an example of the self-shielded flux-cored wire of the present invention, the aluminum powder has a particle size of 60-80 mesh.

[0024] In an example of the self-shielded flux-cored wire of the present invention, the metallic manganese has a particle size of 60-80 mesh.

[0025] In an example of the self-shielded flux-cored wire of the present invention, the silicon iron has a particle size of 60-80 mesh.

[0026] In an example of the self-shielded flux-cored wire of the present invention, the silicon-calcium alloy has a particle size of 60-80 mesh.

[0027] In an example of the self-shielded flux-cored wire of the present application, the wollastonite has a particle size of 60-80 mesh.

[0028] In an example of the self-shielded flux-cored wire of the present application, the fluorite has a particle size of 60-80 mesh.

[0029] In an example of the self-shielded flux-cored wire of the present application, the potassium fluosilicate has a particle size of 60-80 mesh.

[0030] In an example of the self-shielded flux-cored wire of the present application, the lithium fluoride has a particle size of 60-80 mesh.

[0031] In an example of the self-shielded flux-cored wire of the present application, the nickel powder has a particle size of 60-80 mesh.

[0032] In an example of the self-shielded flux-cored wire of the present application, the self-shielded flux-cored wire has a diameter of 0.8-1.6 mm.

[0033] In an example of the self-shielded flux-cored wire of the present application, the mass of the flux material is 12-17% of the sum of the mass of the flux material and the mass of the steel strip sheath.

[0034] In an example of the self-shielded flux-cored wire of the present application, the steel strip sheath is a cold-rolled carbon steel strip, and the thickness of the cold-rolled carbon steel strip is 0.3-0.6 mm.

[0035] The present application also provides a preparation method of the self-shielded flux-cored wire, comprising the following steps:

[0036] S1, weighing and drying each raw material;

[0037] S2, uniformly mixing the dried raw materials to obtain a flux material mixture;

[0038] S3, rolling a steel strip into a U-shaped groove;

[0039] S4, filling the flux material mixture into the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0040] S5, continuing to reduce the diameter of the first welding wire to 4 mm and then entering a drawing machine for drawing;

[0041] S6, using a die to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire in the first pass of drawing the first welding wire in the drawing machine to obtain a second welding wire;

[0042] S7, drawing the second welding wire to a preset diameter to obtain the self-shielded flux-cored wire.

[0043] In the preparation method of the self-protection flux-cored wire, the weighed barium fluoride, wollastonite and fluorite are dried at 400 DEG C for 240 minutes, and then taken out after being cooled to room temperature, and the remaining weighed raw materials are dried at 170 DEG C for 120 minutes, and then taken out after being cooled to room temperature, to obtain the dried raw materials.

[0044] The effects of the components in the self-protection flux-cored wire are as follows:

[0045] The barium fluoride is a main slagging, gas making and dehydrogenation material, has a better arc stabilizing effect than the traditional calcium fluoride, ensures good welding process, and can ensure good all-position welding due to the fast condensation speed of the barium fluoride slag.

[0046] The potassium fluosilicate can improve the stability of the welding arc, reduce the surface tension of the molten slag, refine the droplet and reduce the spatter, and the excessive addition of the potassium fluosilicate can increase the spatter, so the amount of the potassium fluosilicate is controlled to be 0.5-2% of the total amount of the flux powder.

[0047] The aluminum powder and the aluminum-magnesium alloy have a great affinity with oxygen and nitrogen in the air, can play a deoxidizing and denitrifying role, and can significantly improve the porosity resistance of the welding wire.

[0048] The spherical particle characteristics of the atomized iron powder can improve the overall flowability of the flux powder and ensure uniform filling and forming of the flux powder.

[0049] The metal manganese and the ferrosilicon are deoxidizers, which are used to reduce the oxygen content of the weld metal, increase the strength and crack resistance of the weld metal, and reasonably match the nickel powder to have a high content of acicular ferrite, effectively improve the low-temperature impact toughness of the weld metal.

[0050] The silicon-calcium alloy is a common denitrifying agent of the flux-cored wire, and appropriate addition can reduce the porosity sensitivity, and excessive addition can reduce the toughness of the weld metal.

[0051] The addition of the wollastonite can adjust the viscosity, melting point, surface tension and flowability of the molten slag.

[0052] The lithium fluoride and the fluorite can remove hydrogen, and appropriate addition can stabilize the arc.

[0053] The self-protection flux-cored wire and the preparation method thereof, through the combined action of each component in the raw material, the wire can be all-position welding without gas protection, and has good welding process performance and low porosity sensitivity, and the fluorinated graphene coating with strong hydrophobicity, high temperature resistance and good conductivity coated on the surface of the wire can effectively prevent the invasion of moisture in the air, so that the wire has moisture resistance and is easy to store without affecting the welding performance DETAILED DESCRIPTION

[0054] The advantages and effects of the present application can be easily understood by those skilled in the art from the description of the present application. The present application can also be implemented or applied by different specific embodiments, and the details in the description can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the following examples and features in the examples can be combined with each other without conflict. It should also be understood that the terms used in the examples of the present application are for describing specific embodiments, not for limiting the protection scope of the present application. The test methods in the following examples are not specified, and are usually carried out under conventional conditions or under conditions recommended by the manufacturers.

[0055] When the examples give numerical ranges, it should be understood that, unless otherwise specified by the present application, each numerical range has two endpoints and any number between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present application are consistent with the mastery of the prior art by those skilled in the art and the description of the present application, and any method, equipment and material of the prior art similar or equivalent to the method, equipment and material described in the examples of the present application can be used to realize the present application.

[0056] It should be understood that the terms such as "upper", "lower", "left", "right", "middle" and "one" used in the description are only for the convenience of clear description, not for limiting the scope of the present application, and the change or adjustment of the relative relationship without substantial change of the technical content is also regarded as the scope of the present application.

[0057] The present application provides a self-protection flux-cored wire, characterized in that it comprises a steel tape sheath, a flux core material and a fluorinated graphene coating, the flux core material is filled in the steel tape sheath, and the fluorinated graphene coating is coated on the outer surface of the steel tape sheath, the flux core material comprises the following mass percentages of raw materials based on the total mass of the flux core material: 30-50% of atomized iron powder, 18-35% of barium fluoride, 10-20% of aluminum-magnesium alloy, 10-20% of aluminum powder, 3-8% of metallic manganese, 2-5% of silicon iron, 1-3% of silicon-calcium alloy, 2-5% of wollastonite, 1-3% of fluorite, 0.5-2% of potassium fluorosilicate, 1-5% of lithium fluoride and 1-3% of nickel powder.

[0058] In an example of the self-shielded flux-cored wire of the present application, the atomized iron powder is added in an amount of 32-43%.

[0059] In an example of the self-shielded flux-cored wire of the present application, the barium fluoride is added in an amount of 19-28%.

[0060] In an example of the self-shielded flux-cored wire of the present application, the aluminum-magnesium alloy is added in an amount of 12-20%.

[0061] In an example of the self-shielded flux-cored wire of the present application, the aluminum powder is added in an amount of 11-15%.

[0062] In an example of the self-shielded flux-cored wire of the present application, the metallic manganese is added in an amount of 4-6%.

[0063] In an example of the self-shielded flux-cored wire of the present application, the silicon-calcium alloy is added in an amount of 2-3%.

[0064] In an example of the self-shielded flux-cored wire of the present application, the fluorite is added in an amount of 1.5-3%.

[0065] In an example of the self-shielded flux-cored wire of the present application, the lithium fluoride is added in an amount of 2.5-5%.

[0066] In an example of the self-shielded flux-cored wire of the present application, the nickel powder is added in an amount of 1.5-3%.

[0067] In an example of the self-shielded flux-cored wire of the present application, the fluorinated graphene used to prepare the fluorinated graphene coating has a particle size of 1-5 μm.

[0068] In an example of the self-shielded flux-cored wire of the present application, the aluminum-magnesium alloy has an aluminum content of 50±3% and a magnesium content greater than or equal to 47%.

[0069] In an example of the self-shielded flux-cored wire of the present application, the silicon-calcium alloy has a calcium content greater than or equal to 28% and a silicon content greater than or equal to 55%.

[0070] In an example of the self-shielded flux-cored wire of the present application, the wollastonite has a SiO2content greater than or equal to 45% and a CaO content greater than or equal to 40%.

[0071] In an example of the self-shielded flux-cored wire of the present application, the self-shielded flux-cored wire has a diameter of 0.8-1.6 mm.

[0072] In an example of the self-shielded flux-cored wire of the present application, the core material has a mass of 12-17% of the sum of the mass of the core material and the steel band sheath.

[0073] In an example of the self-shielded flux-cored wire of the present application, the steel strip sheath is a cold-rolled carbon steel strip, and the thickness of the cold-rolled carbon steel strip is 0.3-0.6 mm.

[0074] The present application also provides a preparation method of the self-shielded flux-cored wire, comprising the following steps:

[0075] S1, weighing and drying each raw material;

[0076] S2, mixing the dried raw materials uniformly to obtain a flux material mixture;

[0077] S3, rolling the steel strip into a U-shaped groove;

[0078] S4, filling the flux material mixture into the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0079] S5, reducing the diameter of the first welding wire to 4 mm and then entering a drawing machine for drawing;

[0080] S6, using a die to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire in the first pass of drawing the first welding wire in the drawing machine to obtain a second welding wire;

[0081] S7, drawing the second welding wire to a preset diameter to obtain the self-shielded flux-cored wire.

[0082] In an example of the preparation method of the self-shielded flux-cored wire of the present application, in step S1, the weighed barium fluoride, wollastonite and fluorite are dried at 400℃ for 240 minutes, and then taken out after being cooled to room temperature; the rest of the weighed raw materials are dried at 170℃ for 120 minutes, and then taken out after being cooled to room temperature, to obtain the dried raw materials.

[0083] The above raw materials can be used in different proportions to form different embodiments. For example, the particle size of the atomized iron powder used in the following embodiment is 60 mesh, the particle size of the barium fluoride is 60 mesh, the particle size of the aluminum-magnesium alloy is 60 mesh, the particle size of the aluminum powder is 60 mesh, the particle size of the metallic manganese is 60 mesh, the particle size of the silicon-iron is 60 mesh, the particle size of the silicon-calcium alloy is 40 mesh, the particle size of the wollastonite is 80 mesh, the particle size of the fluorite is 80 mesh, the particle size of the potassium fluorosilicate is 60 mesh, the particle size of the lithium fluoride is 60 mesh, and the particle size of the nickel powder is 60 mesh. The specific embodiments are shown as follows:

[0084] Example 1

[0085] The mass percentage of each component of the flux material is: atomized iron powder 30%, barium fluoride 35%, aluminum-magnesium alloy 10%, aluminum powder 10%, metallic manganese 3%, silicon-iron 2%, silicon-calcium alloy 1%, wollastonite 2%, fluorite 1.5%, potassium fluorosilicate 1%, lithium fluoride 2.5%, and nickel powder 2%.

[0086] The method for manufacturing the self-shielded flux-cored wire by using the above flux material comprises the following processes:

[0087] S11, drying and keeping the weighed barium fluoride, wollastonite and fluorite at 400 DEG C for 240 minutes, then taking out after reducing to room temperature, and drying and keeping the rest of the weighed raw materials at 170 DEG C for 120 minutes, then taking out after reducing to room temperature, to obtain the dried raw materials;

[0088] S12, mixing the dried raw materials uniformly to obtain a flux material mixture;

[0089] S13, rolling the steel strip into a U-shaped groove;

[0090] S14, filling the flux material mixture into the U-shaped groove, the mass of the flux material mixture accounting for 12% of the total mass of the flux material mixture and the U-shaped groove, then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0091] S15, reducing the first welding wire to 4 mm and then entering a wire drawing machine for drawing;

[0092] S16, using a die to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire in the first pass of drawing the first welding wire by the wire drawing machine to obtain a second welding wire;

[0093] S17, drawing the second welding wire to a preset diameter of 0.8 mm to obtain the self-shielded flux-cored wire.

[0094] Example 2

[0095] The mass percentage of each component of the flux material is: atomized iron powder 43%, barium fluoride 18%, aluminum-magnesium alloy 12%, aluminum powder 10%, metallic manganese 4%, silicon-iron 2.5%, silicon-calcium alloy 2%, wollastonite 3%, fluorite 1%, potassium fluosilicate 0.5%, lithium fluoride 3%, and nickel powder 1%.

[0096] The method for manufacturing the self-shielded flux-cored wire by using the above flux material comprises the following processes:

[0097] S21, drying and keeping the weighed barium fluoride, wollastonite and fluorite at 400 DEG C for 240 minutes, then taking out after reducing to room temperature, and drying and keeping the rest of the weighed raw materials at 170 DEG C for 120 minutes, then taking out after reducing to room temperature, to obtain the dried raw materials;

[0098] S22, mixing the dried raw materials uniformly to obtain a flux material mixture;

[0099] S23, rolling the steel strip into a U-shaped groove;

[0100] S24, filling the drug core material mixture into the U-shaped groove, the mass of the drug core material mixture accounting for 13.5% of the total mass of the drug core material mixture and the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0101] S25, continuing to reduce the diameter of the first welding wire to 4mm and then entering a wire drawing machine for drawing;

[0102] S26, using a die to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire in the first pass of drawing the first welding wire in the wire drawing machine to obtain a second welding wire;

[0103] S27, drawing the second welding wire to a preset diameter of 0.8mm to obtain the self-protection flux-cored wire.

[0104] Example 3

[0105] The mass percentage of each component of the drug core material is: atomized iron powder 50%, barium fluoride 18%, aluminum-magnesium alloy 10%, aluminum powder 10%, metallic manganese 3%, silicon iron 2%, silicon-calcium alloy 1%, wollastonite 2%, fluorite 1%, potassium fluosilicate 0.5%, lithium fluoride 1.5%, and nickel powder 1%.

[0106] The method for manufacturing the self-protection flux-cored wire using the above drug core material includes the following processes:

[0107] S31, drying and keeping the weighed barium fluoride, wollastonite, and fluorite at 400℃ for 240 minutes, then taking them out of the furnace after being reduced to room temperature, and drying and keeping the remaining weighed raw materials at 170℃ for 120 minutes, then taking them out of the furnace after being reduced to room temperature to obtain dried raw materials;

[0108] S32, mixing the dried raw materials uniformly to obtain a drug core material mixture;

[0109] S33, rolling a steel strip into a U-shaped groove;

[0110] S34, filling the drug core material mixture into the U-shaped groove, the mass of the drug core material mixture accounting for 14% of the total mass of the drug core material mixture and the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0111] S35, continuing to reduce the diameter of the first welding wire to 4mm and then entering a wire drawing machine for drawing;

[0112] S36, using a die to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire in the first pass of drawing the first welding wire in the wire drawing machine to obtain a second welding wire;

[0113] S37, drawing the second welding wire to a preset diameter, the preset diameter being 1.0 mm, to obtain the self-shielded flux-cored welding wire.

[0114] Example 4

[0115] The mass percentage of each component of the flux-cored material is: atomized iron powder 30%, barium fluoride 18%, aluminum-magnesium alloy 20%, aluminum powder 15%, metallic manganese 5%, silicon iron 2%, silicon-calcium alloy 1%, wollastonite 2%, fluorite 1%, potassium fluosilicate 2%, lithium fluoride 1%, and nickel powder 3%.

[0116] The method for manufacturing the self-shielded flux-cored welding wire using the above flux-cored material includes the following processes:

[0117] S41, drying and keeping the weighed barium fluoride, wollastonite, and fluorite at 400℃ for 240 minutes, then reducing to room temperature and discharging, and drying and keeping the rest of the weighed raw materials at 170℃ for 120 minutes, then reducing to room temperature and discharging, to obtain the dried raw materials;

[0118] S42, mixing the dried raw materials uniformly to obtain a flux-cored material mixture;

[0119] S43, rolling the steel strip into a U-shaped groove;

[0120] S44, filling the flux-cored material mixture into the U-shaped groove, the mass of the flux-cored material mixture accounting for 14.5% of the total mass of the flux-cored material mixture and the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0121] S45, continuing to reduce the diameter of the first welding wire to 4 mm and then entering a drawing machine for drawing;

[0122] S46, using a die in the first pass of drawing the first welding wire in the drawing machine to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire to obtain a second welding wire;

[0123] S47, drawing the second welding wire to a preset diameter, the preset diameter being 1.0 mm, to obtain the self-shielded flux-cored welding wire.

[0124] Example 5

[0125] The mass percentage of each component of the flux-cored material is: atomized iron powder 30%, barium fluoride 18%, aluminum-magnesium alloy 10%, aluminum powder 20%, metallic manganese 8%, silicon iron 5%, silicon-calcium alloy 3%, wollastonite 2%, fluorite 1%, potassium fluosilicate 0.5%, lithium fluoride 1%, and nickel powder 1.5%.

[0126] The method for manufacturing the self-shielded flux-cored welding wire using the above flux-cored material includes the following processes:

[0127] S51, drying and keeping the weighed barium fluoride, wollastonite and fluorite at 400℃ for 240 minutes, then reducing to room temperature and discharging, drying and keeping the rest of the weighed raw materials at 170℃ for 120 minutes, then reducing to room temperature and discharging, to obtain dried raw materials;

[0128] S52, mixing the dried raw materials uniformly to obtain a core material mixture;

[0129] S53, rolling the steel strip into a U-shaped groove;

[0130] S54, filling the core material mixture into the U-shaped groove, the mass of the core material mixture accounting for 15.5% of the total mass of the core material mixture and the U-shaped groove, then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0131] S55, continuing to reduce the diameter of the first welding wire to 4mm and then entering the drawing machine for drawing;

[0132] S56, using a die in the first pass of drawing the first welding wire in the drawing machine to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire to obtain a second welding wire;

[0133] S57, drawing the second welding wire to a preset diameter of 1.2mm to obtain the self-protection cored wire.

[0134] Example 6

[0135] The mass percentage of each component of the core material is: atomized iron powder 32%, barium fluoride 19%, aluminum-magnesium alloy 13%, aluminum powder 14%, metallic manganese 4%, silicon-iron 2.5%, silicon-calcium alloy 1%, wollastonite 5%, fluorite 3%, potassium fluosilicate 0.5%, lithium fluoride 5%, and nickel powder 1%.

[0136] The method for manufacturing the self-protection cored wire using the above core material includes the following processes:

[0137] S61, drying and keeping the weighed barium fluoride, wollastonite and fluorite at 400℃ for 240 minutes, then reducing to room temperature and discharging, drying and keeping the rest of the weighed raw materials at 170℃ for 120 minutes, then reducing to room temperature and discharging, to obtain dried raw materials;

[0138] S62, mixing the dried raw materials uniformly to obtain a core material mixture;

[0139] S63, rolling the steel strip into a U-shaped groove;

[0140] S64, filling the drug core material mixture into the U-shaped groove, the mass of the drug core material mixture accounting for 15% of the total mass of the drug core material mixture and the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0141] S65, continuing to reduce the diameter of the first welding wire to 4mm and then entering a wire drawing machine for drawing;

[0142] S66, using a die to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire in the first pass of drawing the first welding wire in the wire drawing machine to obtain a second welding wire;

[0143] S67, drawing the second welding wire to a preset diameter of 1.2mm to obtain the self-protection flux-cored wire.

[0144] Example 7

[0145] The mass percentage of each component of the drug core material: atomized iron powder 35%, barium fluoride 21%, aluminum-magnesium alloy 12%, aluminum powder 11%, metallic manganese 6%, silicon iron 3%, silicon-calcium alloy 2%, wollastonite 2.5%, fluorite 2%, potassium fluosilicate 1%, lithium fluoride 3.5%, and nickel powder 1%.

[0146] The method for manufacturing the self-protection flux-cored wire from the above drug core material includes the following processes:

[0147] S71, drying and keeping the weighed barium fluoride, wollastonite, and fluorite at 400°C for 240 minutes, then taking them out of the furnace after being reduced to room temperature, and drying and keeping the rest of the weighed raw materials at 170°C for 120 minutes, then taking them out of the furnace after being reduced to room temperature to obtain the dried raw materials;

[0148] S72, mixing the dried raw materials uniformly to obtain a drug core material mixture;

[0149] S73, rolling a steel strip into a U-shaped groove;

[0150] S74, filling the drug core material mixture into the U-shaped groove, the mass of the drug core material mixture accounting for 16% of the total mass of the drug core material mixture and the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0151] S75, continuing to reduce the diameter of the first welding wire to 4mm and then entering a wire drawing machine for drawing;

[0152] S76, using a die to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire in the first pass of drawing the first welding wire in the wire drawing machine to obtain a second welding wire;

[0153] S77, drawing the second welding wire to a preset diameter, the preset diameter being 1.6 mm, to obtain the self-shielded flux-cored welding wire.

[0154] Example 8

[0155] The mass percentage of each component of the flux material is: atomized iron powder 40%, barium fluoride 28%, aluminum-magnesium alloy 10%, aluminum powder 10%, metallic manganese 3.5%, silicon iron 2%, silicon-calcium alloy 1%, wollastonite 2%, fluorite 1%, potassium fluosilicate 0.5%, lithium fluoride 1%, and nickel powder 1%.

[0156] The method for manufacturing the self-shielded flux-cored welding wire using the above flux material includes the following processes:

[0157] S81, drying and keeping the weighed barium fluoride, wollastonite, and fluorite at 400 DEG C for 240 minutes, then reducing to room temperature and discharging, and drying and keeping the rest of the weighed raw materials at 170 DEG C for 120 minutes, then reducing to room temperature and discharging, to obtain the dried raw materials;

[0158] S82, mixing the dried raw materials uniformly to obtain a flux material mixture;

[0159] S83, rolling the steel strip into a U-shaped groove;

[0160] S84, filling the flux material mixture into the U-shaped groove, the mass of the flux material mixture accounting for 17% of the total mass of the flux material mixture and the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire;

[0161] S85, continuing to reduce the diameter of the first welding wire to 4 mm and then entering a drawing machine for drawing;

[0162] S86, using a die in the first pass of drawing the first welding wire in the drawing machine to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire to obtain a second welding wire;

[0163] S87, drawing the second welding wire to a preset diameter, the preset diameter being 1.6 mm, to obtain the self-shielded flux-cored welding wire.

[0164] The self-shielded flux-cored welding wire of the present application is used to perform various welding tests on the welding wires obtained in Examples 1-8 according to relevant standards, the welding current is 200 A, the welding voltage is 24 V, and the wire feeding speed is 100 mm / s.

[0165] The chemical composition of the deposited metal in the welding tests of each example is shown in Table 1 below:

[0166] Table 1 Chemical composition of deposited metal

[0167]

[0168] The mechanical properties of the deposited metal of the welding test of each embodiment are as shown in Table 2:

[0169] Table 2 Mechanical properties of the deposited metal

[0170]

[0171]

[0172] The diffusible hydrogen (mercury method) of the deposited metal of the welding test of each embodiment is as shown in Table 3:

[0173] Table 3 Diffusible hydrogen value of the deposited metal

[0174]

[0175] The present application provides a self-shielded flux-cored wire and a preparation method thereof, which has the beneficial effects of being able to be welded in all directions, stable mechanical properties, high deposition efficiency, strong anti-porosity ability, and strong anti-hygroscopicity, and is beneficial to effective preservation. Therefore, the present application effectively overcomes some practical problems in the prior art, thereby having high utilization value and use significance. The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.

Claims

1. A self-shielded flux-cored welding wire, characterized by The self-protection flux-cored wire comprises a steel belt sheath, a core material filled in the steel belt sheath, and a fluorinated graphene coating coated on the outer surface of the steel belt sheath, wherein the core material consists of the following raw materials in mass percentage, based on the total mass of the core material: Atomized iron powder 30-50%, barium fluoride 18-35%, aluminum-magnesium alloy 10-20%, aluminum powder 10-20%, metallic manganese 3-8%, silicon iron 2-5%, silicon-calcium alloy 1-3%, wollastonite 2-5%, fluorite 1-3%, potassium fluosilicate 0.5-2%, lithium fluoride 1-5%, and nickel powder 1-3%; The aluminum content in the aluminum-magnesium alloy is 50±3%, and the magnesium content is greater than or equal to 47%; the calcium content in the silicon-calcium alloy is greater than or equal to 28%, and the silicon content is greater than or equal to 55%; the content of SiO2 in the wollastonite is greater than or equal to 45%, and the content of CaO is greater than or equal to 40%.

2. The self-protecting flux cored wire of claim 1, wherein The particle size of the fluorinated graphene used for preparing the fluorinated graphene coating is 1-5 μm.

3. The self-protecting flux cored wire of claim 1, wherein The diameter of the self-protection flux-cored wire is 0.8-1.6 mm.

4. The self-protecting flux cored wire of claim 1, wherein The mass of the core material is 12-17% of the sum of the mass of the core material and the mass of the steel belt sheath.

5. The self-protecting flux cored wire of claim 1, wherein The steel belt sheath is a cold-rolled carbon steel belt, and the thickness of the cold-rolled carbon steel belt is 0.3-0.6 mm.

6. A method of making a self-shielded flux cored wire as claimed in any one of claims 1 to 5, characterized in that, The method comprises the following steps: S1, drying each raw material after weighing; S2, mixing the dried raw materials uniformly to obtain a core material mixture; S3, rolling a steel belt into a U-shaped groove; S4, filling the core material mixture into the U-shaped groove, and then rolling the U-shaped groove into an O-shaped groove to obtain a first welding wire; S5, continuing to reduce the diameter of the first welding wire to 4 mm and then entering a drawing machine for drawing; S6, using a die to compress and coat a fluorinated graphene coating on the outer surface of the first welding wire in the first pass of drawing the first welding wire in the drawing machine to obtain a second welding wire; S7, drawing the second welding wire to a preset diameter to obtain the self-protection flux-cored wire.

7. The method of making a self-protecting flux cored wire of claim 6, wherein, In step S1, the weighed barium fluoride, wollastonite, and fluorite are dried at 400℃ for 240 minutes, and then taken out after being cooled to room temperature; the remaining weighed raw materials are dried at 170℃ for 120 minutes, and then taken out after being cooled to room temperature, to obtain the dried raw materials.

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