Low-density steel wear-resistant welding wire and preparation method thereof

Abstract

The invention relates to a low-density steel wear-resistant welding wire and a preparation method thereof, and belongs to the technical field of welding materials, the low-density steel wear-resistant welding wire comprises, by mass, 0.7-1.1% of C, 5-11% of Al, 0.3-0.9% of Si, 10-15% of Mn, 3-5% of Ni, less than or equal to 0.035% of P, less than or equal to 0.010% of S, and the balance Fe and inevitable impurities. Chemical components of the low-density steel welding wire are designed, Mn is partially replaced with Ni, work hardening is reduced, a steel strip is filled with alloy powder through a flux-cored wire technology, and the welding wire is prepared through the steps of drying, powder mixing, forming, drawing and the like. The problems that the low-density steel welding wire is difficult to draw and poor in welding performance are solved, the welding wire and base metal components are well matched, the welding process is stable, and welding and repairing of low-density steel structural parts are achieved.

Description

Technical Field

[0001] This invention belongs to the field of low-density steel welding, specifically relating to a low-density steel wear-resistant welding wire and its preparation method. Background Technology

[0002] With the increasing demand for lightweight and mobility in special-purpose vehicles, lightweight materials have become a research hotspot. Conventional aluminum alloys and titanium alloys have achieved good results in vehicle lightweighting, but the wear resistance and high cost of lightweight alloys limit their widespread application in special-purpose vehicles.

[0003] Currently, Fe-Mn-Al-C series high-strength steel is a widely studied low-density steel material that can effectively achieve lightweight design of vehicle structural components while ensuring high wear resistance and strength. It has been reported that adding 1% Al to steel reduces the density by 0.101 g / cm³. 3 For every 1% increase in carbon (C) added to steel, the density decreases by 0.41 g / cm³. 3 For every 1% Mn added to steel, the density decreases by 0.0086 g / cm³. 3 Its density can reach 6.2 g / cm³. 3 -7.2g / cm 3 It plays an important role in the lightweight design of special vehicles.

[0004] The chemical composition (mass percentage) of A350L-2 low-density steel is as follows: C 1.1~1.3%, Mn 27.00~29.00%, Si ≤0.30%, Al 10.00~11.00%, P ≤0.035%, S ≤0.010%, with the balance being Fe and unavoidable impurities. A350L-2 low-density steel contains 1.1%~1.3% carbon, with a carbon equivalent of approximately 6%. When the carbon equivalent is ≥0.6%, weldability is poor, classifying it as a difficult-to-weld material requiring high preheating temperatures and strict processing methods. The carbon equivalent of low-density steel is much greater than 0.6%, resulting in particularly poor weldability. Welding the surface of A350L-2 low-density steel using TIG welding under pure argon protection resulted in weld cracking. Furthermore, the low-density steel contains 10.00%~11.00% Al, making it prone to oxidation during welding; therefore, a pure argon protective atmosphere is required for welding. The production of matching welding wires by directly drawing low-density steel is difficult due to severe work hardening of the material. Therefore, no welding material with good welding effect for low-density steel has been found at present. Summary of the Invention

[0005] This invention provides a low-density steel wear-resistant welding wire and its preparation method, based on the principle of consistency between welding materials and base materials. The technical problem to be solved is to address the difficulties in drawing low-density steel welding wire caused by work hardening, thereby enabling effective repair welding and maintenance of low-density steel structural components.

[0006] To solve the above technical problems, the present invention provides a low-density steel wear-resistant welding wire, characterized in that: the chemical composition by mass percentage is: C 0.7~1.1%, Al 5~11%, Si 0.3~0.9%, Mn 10~15%, Ni 3~5%, P ≤0.035%, S ≤0.010%, with the balance being Fe and unavoidable impurities.

[0007] A method for preparing a low-density steel wear-resistant welding wire, characterized by comprising the following steps: S1. Provide low-carbon steel strip and alloy powder, the alloy powder including graphite, ferrosilicon, electrolytic manganese, high-purity nickel and high-purity aluminum; S2. Dry and mix the alloy powder; S3. Clean the steel strip, shape it into a U-shape, and fill it with the alloy powder; S4. After multiple drawing passes to the target diameter, the flux-cored welding wire is obtained.

[0008] Furthermore: The mass ratio range of graphite, ferrosilicon, electrolytic manganese, high-purity nickel, and high-purity aluminum in the alloy powder is as follows: Graphite: 30-40g Ferrosilicon: 15-30g Electrolytic manganese metal: 450-530g High-purity nickel: 150-160g High-purity aluminum: 260-340g The total weight of all the above components is 1000g.

[0009] Furthermore, it also includes adding an arc stabilizer to the alloy powder, wherein the arc stabilizer is potassium feldspar, and the addition amount is 70-90g.

[0010] Furthermore, the drying temperature is 60-80℃, and the drying time is 4 hours.

[0011] Furthermore: the mixing is carried out in a powder mixer at a speed of 30 rpm, each mixing session lasts for 20 minutes, and is repeated 3-5 times.

[0012] Furthermore: the steel strip is Q235 steel strip with a thickness × width of 0.4 × 10 mm.

[0013] Furthermore, the fill rate is 14-18%.

[0014] Furthermore, the chemical composition of the welding wire by mass percentage is: C 1.1%, Al 11%, Si 0.9%, Mn 15%, Ni 5%, P 0.035%, S 0.010%, with the balance being Fe and impurities.

[0015] Further, the chemical composition of the welding wire by mass percentage is: C 0.9%, Al 8%, Si 0.6%, Mn 12.5%, Ni 4%, P 0.035%, S 0.010%, with the balance being Fe and impurities.

[0016] Beneficial effects: This invention enables the preparation of low-density steel welding wire using flux-cored welding wire. Furthermore, by adjusting the chemical composition of Fe-Mn-Al-C low-density steel and designing a mixing method for low-density steel powder, the composition of low-density steel wear-resistant flux-cored welding wire can be rationally controlled, thereby achieving the preparation of low-density steel wear-resistant welding wire.

[0017] This invention replaces a portion of the Mn content with Ni to ensure the strength of the steel and reduce work hardening. It designs a novel chemical composition for low-density steel welding wire and employs a flux-cored wire process to fill alloy powder into steel strips. Through drying, mixing, forming, and drawing steps, a low-density steel wear-resistant welding wire is prepared, enabling the welding and repair of low-density steel structural components. This invention solves the problems of difficult drawing and poor welding performance of low-density steel welding wire, ensuring good compositional matching between the welding wire and the base material, and resulting in a stable welding process. Detailed Implementation

[0018] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below.

[0019] The present invention proposes a low-density steel wear-resistant welding wire with the following chemical composition (mass percentage): C 0.7~1.1%, Al 5~11%, Si 0.3~0.9%, Mn 10~15%, Ni 3~5%, P ≤0.035%, S ≤0.010%, and the balance being Fe and unavoidable impurities.

[0020] Example 1: 1. Chemical composition (mass percentage) of low-density steel: C 0.7%, Al 5%, Si 0.3%, Mn 10%, Ni 3%, P = 0.035%, S = 0.010%, balance Fe and unavoidable impurities.

[0021] 2. Preparation: Prepare a roll of Q235 steel strip with a thickness × width of 0.4 × 10 mm, and 1000 g of graphite powder (36.9 g), ferrosilicon powder (15.8 g), electrolytic manganese powder (525.8 g), high-purity nickel powder (157.9 g), and high-purity aluminum powder (263.6 g) with a diameter less than 80 mesh; also prepare 80 g of potassium feldspar as an arc stabilizer.

[0022] 3. Powder mixing and drying: Pour the above powder into a drying tray and place it in a drying oven. Dry at 60ºC for 4 hours. When the equipment is running, the oven door must not be opened. After the machine is stopped, let it cool to room temperature with the oven. Put the powder into the powder mixer, turn on the mixer, and mix the powder for 20 minutes at a speed of 30 rpm. Repeat the mixing process 5 times. After mixing, pour the powder into the powder bucket and transport it to the molding machine.

[0023] 4. Steel strip rewinding: Use a double-headed magnetic hoist to lift the steel strip onto the unwinding machine. Use an argon arc welding machine to butt-weld multiple sections of steel strip. The thickness of the butt weld should not exceed the thickness of the steel strip, and the width should not exceed the width of the steel strip. The weld joint should be fully penetrated and fused. Then rewind the steel strip on the I-beam reel, ensuring that the width of the steel strip does not exceed the outer end of the I-beam reel.

[0024] 5. Forming and Drawing: The steel strip is placed on the pay-off machine. The rough, edged surface of the steel strip is the powder-filled surface, while the smooth surface is the exposed surface during drawing, facing the center of the I-beam roller. Before forming, the steel strip is cleaned in an ultrasonic cleaner at a temperature of 60ºC. After cleaning, forming and drawing begin. Starting from the pay-off machine, the steel strip passes sequentially through the ultrasonic cleaner, forming machine, 6-section wire drawing machine, and take-up machine. Finally, the welding wire is threaded into the sizing die and drawn to the final diameter of the welding wire. The forming machine extrudes the steel strip into a U-shape while simultaneously filling it with powder at a rate of 16%. After powder filling, the steel strip is segmented, pressed, and drawn to a final diameter of 1.6mm using the wire drawing machine. The die sizes for the wire drawing machine are 2.75mm, 2.39mm, 2.11mm, 1.89mm, 1.72mm, and 1.56mm.

[0025] 6. Welding wire layer winding and packaging: Adjust the slack diameter and warp of the welding wire using the straightener on the layer winding equipment (slack diameter ≥ 600 mm, warp ≤ 10 mm required), layer winding is performed according to the weight of 15 kg per coil of welding wire, and packaging is carried out after layer winding is completed.

[0026] Welding wire performance: Welding is performed using TIG welding and pure argon gas protection. The welding process is stable and the weld fusion effect is good.

[0027] Example 2: 1. The chemical composition (mass percentage) of the low-density steel used in this invention is as follows: C 1.1%, Al 11%, Si 0.9%, Mn 15%, Ni 5%, P = 0.035%, S = 0.010%, with the balance being Fe and unavoidable impurities.

[0028] 2. Preparation: Prepare a roll of Q235 steel strip with a thickness × width of 0.4 × 10 mm, and 1000 g of the following: 33.3 g of graphite powder, 27.3 g of ferrosilicon powder, 454.5 g of electrolytic manganese powder, 151.5 g of high-purity nickel powder, and 333.3 g of high-purity aluminum powder (diameter less than 80 mesh); and 80 g of potassium feldspar as an arc stabilizer.

[0029] 3. Powder mixing and drying: Pour the above powder into a drying tray and place it in a drying oven. Dry at 60ºC for 4 hours. When the equipment is running, the oven door must not be opened. After the machine is stopped, let it cool to room temperature with the oven. Put the powder into the powder mixer, turn on the mixer, and mix the powder for 20 minutes at a speed of 30 rpm. Repeat the mixing process 5 times. After mixing, pour the powder into the powder bucket and transport it to the molding machine.

[0030] 4. Steel strip rewinding: Use a double-headed magnetic hoist to lift the steel strip onto the unwinding machine. Use an argon arc welding machine to butt-weld multiple sections of steel strip. The thickness of the butt weld should not exceed the thickness of the steel strip, and the width should not exceed the width of the steel strip. The weld joint should be fully penetrated and fused. Then rewind the steel strip on the I-beam reel, ensuring that the width of the steel strip does not exceed the outer end of the I-beam reel.

[0031] 5. Forming and Drawing: The steel strip is placed on the pay-off machine. The rough, edged surface of the steel strip is the powder-filled surface, while the smooth surface is the exposed surface during drawing, facing the center of the I-beam roller. Before forming, the steel strip is cleaned in an ultrasonic cleaner at a temperature of 60ºC. After cleaning, forming and drawing begin. Starting from the pay-off machine, the steel strip passes sequentially through the ultrasonic cleaner, forming machine, 6-section wire drawing machine, and take-up machine. Finally, the welding wire is threaded into the sizing die and drawn to the final diameter of the welding wire. The forming machine extrudes the steel strip into a U-shape while simultaneously filling it with powder at a rate of 16%. After powder filling, the steel strip is segmented, pressed, and drawn to a final diameter of 1.6mm using the wire drawing machine. The die sizes for the wire drawing machine are 2.75mm, 2.39mm, 2.11mm, 1.89mm, 1.72mm, and 1.56mm.

[0032] 6. Welding wire layer winding and packaging: Adjust the slack diameter and warp of the welding wire using the straightener on the layer winding equipment (slack diameter ≥ 600 mm, warp ≤ 10 mm required), layer winding is performed according to the weight of 15 kg per coil of welding wire, and packaging is carried out after layer winding is completed.

[0033] Welding wire performance: Welding is performed using TIG welding and pure argon gas protection. The welding process is stable and the weld fusion effect is good.

[0034] Example 3: 1. The chemical composition (mass percentage) of the low-density steel used in this invention is as follows: C 0.9%, Al 8%, Si 0.6%, Mn 12.5%, Ni 4%, P = 0.035%, S = 0.010%, with the balance being Fe and unavoidable impurities.

[0035] 2. Preparation: Prepare a roll of Q235 steel strip with a thickness × width of 0.4 × 10 mm, and 1000 g of graphite powder (34.6 g), ferrosilicon powder (23.1 g), electrolytic manganese powder (480.8 g), high-purity nickel powder (153.8 g), and high-purity aluminum powder (307.7 g) with a diameter less than 80 mesh; also prepare 80 g of potassium feldspar as an arc stabilizer.

[0036] 3. Powder mixing and drying: Pour the above powder into a drying tray and place it in a drying oven. Dry at 60ºC for 4 hours. When the equipment is running, the oven door must not be opened. After the machine is stopped, let it cool to room temperature with the oven. Put the powder into the powder mixer, turn on the mixer, and mix the powder for 20 minutes at a speed of 30 rpm. Repeat the mixing process at least 3 times. After mixing, pour the powder into the powder bucket and transport it to the molding machine.

[0037] 4. Steel strip rewinding: Use a double-headed magnetic hoist to lift the steel strip onto the unwinding machine. Use an argon arc welding machine to butt-weld multiple sections of steel strip. The thickness of the butt weld should not exceed the thickness of the steel strip, and the width should not exceed the width of the steel strip. The weld joint should be fully penetrated and fused. Then rewind the steel strip on the I-beam reel, ensuring that the width of the steel strip does not exceed the outer end of the I-beam reel.

[0038] 5. Forming and Drawing: The steel strip is placed on the pay-off machine. The rough, edged surface of the steel strip is the powder-filled surface, while the smooth surface is the exposed surface during drawing, facing the center of the I-beam roller. Before forming, the steel strip is cleaned in an ultrasonic cleaner at a temperature of 60ºC. After cleaning, forming and drawing begin. Starting from the pay-off machine, the steel strip passes sequentially through the ultrasonic cleaner, forming machine, 6-section wire drawing machine, and take-up machine. Finally, the welding wire is threaded into the sizing die and drawn to the final diameter of the welding wire. The forming machine extrudes the steel strip into a U-shape while simultaneously filling it with powder at a rate of 16%. After powder filling, the steel strip is segmented, pressed, and drawn to a final diameter of 1.6mm using the wire drawing machine. The die sizes for the wire drawing machine are 2.75mm, 2.39mm, 2.11mm, 1.89mm, 1.72mm, and 1.56mm.

[0039] 6. Welding wire layer winding and packaging: Adjust the slack diameter and warp of the welding wire using the straightener on the layer winding equipment (slack diameter ≥ 600 mm, warp ≤ 10 mm required), layer winding is performed according to the weight of 15 kg per coil of welding wire, and packaging is carried out after layer winding is completed.

[0040] Welding wire performance: Welding is performed using TIG welding and pure argon gas protection. The welding process is stable and the weld fusion effect is good.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A low density steel wear-resistant welding wire, characterized by: Chemical composition: C 0.7~1.1%, Al 5~11%, Si 0.3~0.9%, Mn 10~15%, Ni 3~5%, P ≤0.035%, S ≤0.010%, the balance being Fe and inevitable impurities.

2. The method of producing a low-density steel wear-resistant welding wire according to claim 1, characterized in that, The method comprises the following steps: S1, providing a low carbon steel strip and alloy powder, the alloy powder comprising graphite, ferrosilicon, electrolytic manganese, high-purity nickel and high-purity aluminum; S2, drying and mixing the alloy powder; S3, cleaning the steel strip, forming the steel strip into a U shape, and filling the alloy powder into the U-shaped steel strip; S4, drawing the U-shaped steel strip to a target diameter to obtain a flux-cored wire.

3. The preparation method of claim 2, wherein: the mass ratio of the graphite, ferrosilicon, electrolytic manganese, high-purity nickel and high-purity aluminum in the alloy powder is: graphite: 30-40g, ferrosilicon: 15-30g, electrolytic manganese: 450-530g, high-purity nickel: 150-160g, and high-purity aluminum: 260-340g, and the total amount of the above components is 1000g. The method further comprises adding an arc stabilizing agent to the alloy powder, the arc stabilizing agent being potassium feldspar and the amount of the arc stabilizing agent being 70-90g. The drying temperature is 60-80°C and the drying time is 4 hours. The mixing is performed in a powder mixer at a speed of 30 revolutions per minute, each mixing being performed for 20 minutes, and the mixing being repeated for 3-5 times. The steel strip is a Q235 steel strip with a thickness x width of 0.4 x 10mm. The filling rate is 14-18%. The chemical composition of the welding wire is: C 1.1%, Al 11%, Si 0.9%, Mn 15%, Ni 5%, P 0.035%, S 0.010%, the balance being Fe and impurities. The chemical composition of the welding wire is: C 0.9%, Al 8%, Si 0.6%, Mn 12.5%, Ni 4%, P 0.035%, S 0.010%, the balance being Fe and impurities.

4. The method of claim 2, wherein: ​ 5. The method of claim 2, wherein: ​ 6. The method of claim 2, wherein: ​ 7. The method of claim 2, wherein: ​ 8. The method of claim 2, wherein: ​ 9. The method of claim 2, wherein: ​ 10. The method of claim 2, wherein: ​