A strong wear-resistant low-dilution gas shielded welding wire and a preparation method thereof

Abstract

The disclosure provides a strong wear-resistant low-dilution gas shield welding wire and a preparation method thereof, and belongs to the technical field of welding wire manufacturing. The welding wire is composed of the following raw materials in parts by weight: 45-52 parts by weight of iron; 18-22 parts by weight of electrolytic nickel plate; 6-8 parts by weight of high-purity molybdenum powder; 4-6 parts by weight of nano-tungsten powder; 3-4.5 parts by weight of vanadium nitride alloy; 1.2-1.8 parts by weight of niobium-iron alloy; 0.8-1.5 parts by weight of aluminum-magnesium alloy powder; 0.3-0.6 parts by weight of lanthanum-cerium mixed rare earth; 0.15-0.25 parts by weight of boron-iron alloy; 0.5-0.8 parts by weight of metallic silicon powder; 0.2-0.4 parts by weight of magnesium-calcium alloy; and 0.1-0.3 parts by weight of titanium hydride powder. The disclosure forms a hard skeleton through the gradient distribution of carbides such as molybdenum, tungsten and vanadium, significantly improves the wear resistance life, reduces the melt mixing of the base material through the nickel-based alloy, ensures the consistency of the deposited metal composition, fixes the free hydrogen through the hydrogen trap phase such as titanium and niobium, and blocks the moisture absorption path combined with the surface passivation film.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas shielded welding and welding wire manufacturing, and particularly relates to a highly wear-resistant and low-dilution gas shielded welding wire and a preparation method thereof. Background Art

[0002] Welding wire relies on coating or flux for protection and alloying, which is prone to produce slag and has low welding efficiency. Gas shielded welding wire, on the other hand, can isolate the air through external gas, and has the advantages of high deposition efficiency and good weld cleanliness. It is widely used in high-precision automated welding scenarios such as automobile manufacturing, ship welding, and pressure vessels. The core difference lies in the protection method and alloying path. The alloying elements of gas shielded welding wire are directly integrated into the wire matrix, reducing welding smoke and improving process controllability.

[0003] However, existing gas shielded welding wires often have significant disadvantages due to uneven materials or process limitations: first, the segregation of alloy elements leads to a decrease in weld toughness, which is prone to thermal cracking; second, moisture absorption by the welding wire causes hydrogen embrittlement, reducing the fatigue strength of the joint; third, the wear resistance is insufficient, and the service life is short under surfacing or high wear conditions; fourth, the dilution rate is high, and the composition of the fusion zone fluctuates greatly, affecting the reliability of welding dissimilar materials. Therefore, the above problems jointly restrict its application in the field of high-strength steel connection in harsh environments.

[0004] In view of the above technical problems, it is necessary to propose a strong wear-resistant and low-dilution gas shielded welding wire and a preparation method thereof to solve the above technical problems. Summary of the Invention

[0005] The present disclosure aims to solve at least one of the technical problems existing in the prior art and provide a highly wear-resistant and low-dilution gas shielded welding wire and a preparation method thereof.

[0006] In one aspect of the present disclosure, there is provided a highly wear-resistant and low-dilution gas shielded welding wire, the welding wire comprising:

[0007] 45-52 parts by weight of iron;

[0008] 18-22 parts by weight of electrolytic nickel plate;

[0009] 6-8 parts by weight of high-purity molybdenum powder;

[0010] 4-6 parts by weight of nano-tungsten powder;

[0011] 3-4.5 parts by weight of vanadium nitride alloy;

[0012] 1.2-1.8 parts by weight of ferroniobium alloy;

[0013] 0.8-1.5 parts by weight of aluminum-magnesium alloy powder;

[0014] 0.3-0.6 parts by weight of lanthanum-cerium mixed rare earth;

[0015] 0.15-0.25 parts by weight of ferroboron alloy;

[0016] 0.5-0.8 parts by weight of metallic silicon powder;

[0017] 0.2-0.4 parts by weight of magnesium-calcium alloy;

[0018] 0.1-0.3 parts by weight of titanium hydride powder.

[0019] Optionally, the particle size of the nano tungsten powder is 200-400 nm.

[0020] Optionally, the nitrogen content of the vanadium nitride alloy is 18-22%; and / or,

[0021] The niobium content in the ferroniobium alloy is 60-65%; and / or,

[0022] The magnesium content in the aluminum-magnesium alloy is 4-6%.

[0023] Optionally, the lanthanum-cerium mixed rare earth includes lanthanum oxide and cerium oxide, and the mass ratio of the lanthanum oxide to the cerium oxide is 7:3.

[0024] Another aspect of the present disclosure provides a method for preparing the aforementioned highly wear-resistant, low-dilution gas shielded welding wire, the method comprising:

[0025] 45-52 parts by weight of iron, 18-22 parts by weight of electrolytic nickel plate, 6-8 parts by weight of high-purity molybdenum powder, 4-6 parts by weight of nano-tungsten powder, 3-4.5 parts by weight of vanadium nitride alloy, and 1.2-1.8 parts by weight of ferroniobium alloy are placed into a smelting furnace, subjected to heat preservation treatment, and then 0.3-0.6 parts by weight of lanthanum-cerium mixed rare earth and 0.15-0.25 parts by weight of ferroboron alloy are added for deoxidation and purification treatment to obtain a molten alloy liquid;

[0026] The molten alloy liquid is subjected to centrifugal atomization treatment under argon protection to form pre-alloyed powder;

[0027] The pre-alloyed powder is dry-mixed with 0.8-1.5 parts by weight of aluminum-magnesium alloy powder, 0.2-0.4 parts by weight of magnesium-calcium alloy, 0.5-0.8 parts by weight of metallic silicon powder, and 0.1-0.3 parts by weight of titanium hydride powder by ball milling to obtain a mixed powder;

[0028] The mixed powder is placed in a soft-pack mold and subjected to hot isostatic pressing to obtain a green body;

[0029] The green body is sintered and hot extruded to obtain a rod.

[0030] The rod is subjected to drawing and annealing treatments to obtain welding wire.

[0031] Optionally, the green body is sintered using a two-stage sintering process of a low temperature stage and a high temperature stage, wherein:

[0032] Low temperature section: 800-850℃ for 1 hour; high temperature section: 1250-1300℃ for 2 hours, hydrogen partial pressure 0.05-0.1MPa;

[0033] The temperature of hot extrusion of the green body is 1100-1150° C., the extrusion ratio is 12:1, and during the hot extrusion process, the surface of the rod is sprayed with a nano-graphite lubricant with a thickness of 2-5 μm.

[0034] Optionally, four drawing passes are used, with a diameter reduction rate of ≤20% in each pass and a drawing speed of 8-12 m / min, a diameter reduction rate of ≤8% in the final pass, and a drawing speed reduced to 4-6 m / min, and annealing is performed in a hydrogen protection annealing furnace after every two drawing passes.

[0035] Optionally, the particle size of the pre-alloyed powder is 50-150 μm; and / or,

[0036] The diameter of the rod is 7-9 mm; and / or,

[0037] The diameter of the welding wire is 1-1.3 mm.

[0038] Optionally, after the rod is subjected to drawing and annealing to obtain the welding wire, the method further comprises:

[0039] Electroplating a dense copper layer with a thickness of 0.5-1 μm on the surface of the welding wire to obtain a copper-plated welding wire;

[0040] The copper-plated welding wire is placed in a nitrogen atmosphere and kept warm at 450-500° C. for 8-12 minutes, so that an Al 2 O 3 -MgO passivation film is formed on the surface of the copper-plated welding wire.

[0041] Optionally, after the copper-plated welding wire is subjected to heat preservation treatment, the method further comprises:

[0042] A molybdenum disulfide layer with a thickness of 0.1-0.2 μm is deposited on the surface of the passivation film of the copper-plated welding wire by a magnetron sputtering method.

[0043] The present disclosure provides a strong, wear-resistant, low-dilution gas shielded welding wire and a preparation method thereof. The welding wire is composed of the following raw materials in parts by weight: 45-52 parts by weight of iron; 18-22 parts by weight of electrolytic nickel plate; 6-8 parts by weight of high-purity molybdenum powder; 4-6 parts by weight of nano-tungsten powder; 3-4.5 parts by weight of vanadium nitride alloy; 1.2-1.8 parts by weight of ferroniobium alloy; 0.8-1.5 parts by weight of aluminum-magnesium alloy powder; 0.3-0.6 parts by weight of lanthanum-cerium mixed rare earth; 0.15-0.25 parts by weight of ferroboron alloy; 0.5-0.8 parts by weight of metallic silicon powder; 0.2-0.4 parts by weight of magnesium-calcium alloy; and 0.1-0.3 parts by weight of titanium hydride powder. The present invention systematically breaks through the performance bottleneck of traditional welding wire through multi-phase composite strengthening and process coordinated optimization. A hard skeleton is formed through the gradient distribution of carbides such as molybdenum, tungsten and vanadium, which significantly improves the wear resistance and life. Nickel-based alloys are used to reduce the melting and mixing of the base material to ensure the consistency of the deposited metal composition. Free hydrogen is fixed through hydrogen trap phases such as titanium and niobium, and the surface passivation film is combined to block the moisture absorption path. At the same time, dynamic annealing and composite lubrication are used to suppress molten pool oscillation and conductive nozzle adhesion in the process, making it suitable for high-speed welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a flowchart of a method for preparing a highly wear-resistant, low-dilution gas shielded welding wire according to a specific embodiment of the present disclosure. DETAILED DESCRIPTION

[0045] To enable those skilled in the art to better understand the technical solutions of the present disclosure, the present disclosure is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to illustrate the present disclosure and are part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments of the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present disclosure.

[0046] In one aspect of the present disclosure, a strong, wear-resistant, low-dilution gas shielded welding wire is provided, which is composed of the following raw materials in parts by weight: 45-52 parts by weight of iron; 18-22 parts by weight of electrolytic nickel plate; 6-8 parts by weight of high-purity molybdenum powder; 4-6 parts by weight of nano-tungsten powder; 3-4.5 parts by weight of vanadium nitride alloy; 1.2-1.8 parts by weight of niobium-iron alloy; 0.8-1.5 parts by weight of aluminum-magnesium alloy powder; 0.3-0.6 parts by weight of lanthanum-cerium mixed rare earth; 0.15-0.25 parts by weight of boron-iron alloy; 0.5-0.8 parts by weight of metallic silicon powder; 0.2-0.4 parts by weight of magnesium-calcium alloy; and 0.1-0.3 parts by weight of titanium hydride powder.

[0047] The present invention achieves low segregation, high toughness, resistance to hydrogen embrittlement, super wear resistance and low dilution through multiple mechanisms such as solid solution element strengthening + nano-precipitation + grain boundary purification + hydrogen trapping, and is suitable for welding in harsh environments such as high-strength steel and marine engineering. Among them, a hard skeleton is formed by the gradient distribution of carbides such as molybdenum, tungsten and vanadium, which significantly improves the wear resistance life. The nickel-based alloy reduces the melting and mixing of the parent material to ensure the consistency of the deposited metal composition; free hydrogen is fixed by hydrogen trap phases such as titanium and niobium to reduce the risk of hydrogen-induced delayed cracking; and W and Mo in nano-tungsten powder and high-purity molybdenum powder are dissolved in the iron matrix to form a high-hardness solid solution, while generating wear-resistant carbides. The vanadium nitride particles pin the grain boundaries, hindering the dislocation movement during the wear process and improving the resistance to plastic deformation. The boron iron alloy forms a hard Fe2B phase, which constitutes a multi-scale wear-resistant network with the above-mentioned carbides, and the wear resistance is improved based on the above-mentioned synergistic effect; and the dilution rate is reduced by silicon powder, niobium iron alloy, vanadium nitride, etc.

[0048] It should be noted that the present embodiment does not impose any specific limitation on the sources of the above components, and commercially available ones may be used or synthesized independently.

[0049] Illustratively, the high-purity molybdenum powder is prepared by decomposing ammonium molybdate into MoO3 and then reducing it into Mo in a two-stage reduction process at 850-950°C under a hydrogen atmosphere.

[0050] For example, the nano tungsten powder is prepared by vapor deposition of ammonium paratungstate in an argon plasma environment, with a particle size of 200-400 nm.

[0051] Illustratively, the vanadium nitride alloy is prepared by high-temperature nitriding of metallic vanadium particles in a nitrogen atmosphere, and the nitrogen content in the vanadium nitride alloy is 18-22%.

[0052] Illustratively, ferroniobium alloy is prepared by smelting and reducing niobium concentrate and iron powder in a vacuum induction furnace, with a niobium content of 60-65% and the balance being iron.

[0053] Illustratively, the aluminum-magnesium alloy powder is prepared by atomizing pure aluminum and magnesium ingots under argon protection, with a magnesium content of 4-6% and the remainder being aluminum.

[0054] Illustratively, the lanthanum-cerium mixed rare earth is prepared by subjecting bastnaesite to molten salt electrolysis in an electrolytic cell, wherein the lanthanum-cerium mixed rare earth includes lanthanum oxide and cerium oxide, and the mass ratio of the lanthanum oxide to the cerium oxide is 7:3.

[0055] Illustratively, the titanium hydride powder is prepared by subjecting titanium sponge to a hydrogen absorption reaction at 400-500° C. for 4-6 hours in a hydrogen atmosphere.

[0056] Another aspect of the present disclosure provides a method S100 for preparing the aforementioned highly wear-resistant, low-dilution gas shielded welding wire, specifically comprising the following steps S110 to S160:

[0057] S110, 45-52 parts by weight of iron, 18-22 parts by weight of electrolytic nickel plate, 6-8 parts by weight of high-purity molybdenum powder, 4-6 parts by weight of nano-tungsten powder, 3-4.5 parts by weight of vanadium nitride alloy, and 1.2-1.8 parts by weight of niobium-iron alloy are placed into a smelting furnace, and vacuumed to 5×10 -3 Pa and then heated to 1650-1700°C and kept for 20-40 minutes (for example, preferably 30 minutes), then 0.3-0.6 parts by weight of lanthanum-cerium mixed rare earth and 0.15-0.25 parts by weight of boron iron alloy were added for deoxidation and purification to obtain a molten alloy liquid.

[0058] S120, centrifugally atomizing the molten alloy liquid under argon protection to form pre-alloyed powder.

[0059] In some preferred embodiments, in step S110 , the particle size of the pre-alloyed powder is 50-150 μm.

[0060] S130, dry-mixing the pre-alloyed powder with 0.8-1.5 parts by weight of aluminum-magnesium alloy powder, 0.2-0.4 parts by weight of magnesium-calcium alloy, 0.5-0.8 parts by weight of metallic silicon powder, and 0.1-0.3 parts by weight of titanium hydride powder by ball milling to obtain a mixed powder.

[0061] In some preferred embodiments, in step S130, the pre-alloyed powder is dry-mixed with aluminum-magnesium alloy, magnesium-calcium alloy, metallic silicon powder, and titanium hydride powder in a ball mill at a speed of 120-150 rpm under argon protection for 2-4 hours to ensure uniform dispersion of nanocarbides.

[0062] S140, placing the mixed powder into a soft package mold, and subjecting the mixed powder to hot isostatic pressing to obtain a green body.

[0063] Specifically, the mixed powder was loaded into a soft-pack mold and a pressure of 250 MPa was applied in a cold isostatic press for 10 minutes to obtain a density of ≥7.8 g / cm 3 The body.

[0064] S150, sintering and hot extruding the green body to obtain a rod.

[0065] Specifically, the green body is sintered in a vacuum sintering furnace in two stages: a low-temperature stage at 800-850°C for one hour to activate the diffusion bonding of the aluminum-magnesium alloy; and a high-temperature stage at 1250-1300°C for two hours at a hydrogen partial pressure of 0.05-0.1 MPa to promote in-situ carbide formation. The sintered green body is then heated to 1100-1150°C and hot-extruded into Φ8mm rods at a 12:1 extrusion ratio. A 2-5μm-thick nanographite lubricant is sprayed onto the surface. The layered structure of the nanographite maintains lubricity even at high temperatures (1100-1150°C), reducing the friction coefficient to 0.1-0.15, significantly reducing extrusion resistance and preventing scratches or cracks on the rod surface. Furthermore, the lubricant forms a continuous film, promoting uniform metal flow and preventing cracks or dimensional deviations within the rod caused by localized friction.

[0066] S160, drawing and annealing the rod to obtain welding wire.

[0067] Specifically, the rod is drawn to Φ3.2mm in four passes, with a diameter reduction rate of ≤20% in each pass and a drawing speed of 8-12m / min. Molybdenum disulfide plus nano-diamond composite lubricant is used to reduce the surface friction coefficient to 0.08-0.12;

[0068] After every two drawing passes, a short annealing is performed in a hydrogen protection annealing furnace to eliminate work hardening and retain 50-60% dislocation density to balance strength and plasticity;

[0069] The final drawing is to the target diameter of Φ1.0-1.3mm, the final reduction rate is ≤8%, the drawing speed is reduced to 4-6m / min, and nitrogen cooling is used simultaneously to inhibit grain growth to ensure that the surface roughness Ra is ≤0.8μm.

[0070] Furthermore, in other preferred embodiments, after the rod is subjected to drawing and annealing to obtain the welding wire, the method of the present disclosure further comprises:

[0071] Electroplating a dense copper layer with a thickness of 0.5-1 μm on the surface of the welding wire to obtain a copper-plated welding wire;

[0072] The copper-plated welding wire is placed in a nitrogen atmosphere and kept warm at 450-500° C. for 8-12 minutes, so that an Al 2 O 3 -MgO passivation film is formed on the surface of the copper-plated welding wire.

[0073] Specifically, at a pulse current density of 3-5 A / dm 2, under the condition of plating solution temperature of 35-40℃, electroplate 0.5-1μm dense copper layer with copper purity ≥99.99% to cover the micropores on the surface of the welding wire; place the copper-plated welding wire in a nitrogen atmosphere containing 5-8% oxygen, heat it to 450-500℃ and keep it warm for 10 minutes to preferentially oxidize the aluminum-magnesium alloy to form an Al2O3-MgO composite film, which is the passivation layer formed.

[0074] The present invention forms a dense copper plating layer on the surface of the welding wire, which can cover defects such as micropores and cracks on the surface of the welding wire, prevent moisture and oxygen from penetrating into the matrix, inhibit hydrogen embrittlement and oxidation from the source, effectively isolate environmental moisture, and improve fatigue resistance.

[0075] Furthermore, after the copper-plated welding wire is subjected to heat preservation treatment, the method of the present disclosure further comprises:

[0076] A molybdenum disulfide layer with a thickness of 0.1-0.2 μm is deposited on the surface of the passivation film of the copper-plated welding wire by a magnetron sputtering method.

[0077] Specifically, a 0.1-0.2μm layer of molybdenum disulfide is deposited on the surface of the passivation film using magnetron sputtering at a sputtering power of 200-300W and an argon flow rate of 20-30sccm, reducing wire feeding friction by 35-40%. The MoS2 layer covers the surface of the Al2O3-MgO passivation film, isolating it from mechanical scratches and humid environments, preventing damage to the passivation film and resulting in corrosion of the substrate.

[0078] It should be noted that during the preparation process, a laser diameter gauge can be used to monitor the wire diameter fluctuation in real time, and feedback can be used to adjust the speed of the drawing machine servo motor to ensure diameter consistency.

[0079] Furthermore, the present invention can take samples from the beginning and end of each coil of welding wire, verify the alloy element content using an X-ray fluorescence spectrometer, and focus on monitoring the segregation index of niobium, vanadium, and titanium to prepare a welding wire suitable for high-speed welding.

[0080] The present disclosure systematically breaks through the performance bottleneck of traditional welding wire through multi-phase composite strengthening and process coordinated optimization, forms a hard skeleton through the gradient distribution of carbides such as molybdenum, tungsten, and vanadium, significantly improves the wear resistance and life, reduces the melting and mixing of the base material through nickel-based alloys, ensures the consistency of the deposited metal composition, fixes free hydrogen through hydrogen trap phases such as titanium and niobium, and blocks the moisture absorption path in combination with the surface passivation film. At the same time, in terms of process, dynamic annealing and composite lubrication are used to suppress molten pool oscillation and conductive nozzle adhesion, and adapt to high-speed welding. In summary, the welding wire and its preparation process provided by the present disclosure have high reliability, long life and a wide process window, and are particularly suitable for robot automated welding, wear-resistant component surfacing and high-strength steel connection in harsh environments, solving the problem of wear resistance and low dilution being difficult to strike a balance in the existing technology.

[0081] The following is a further description of the formula and preparation method of the welding wire in conjunction with specific examples:

[0082] Example 1

[0083] The welding wire material composition of this example is shown in Table 1. The preparation method of the welding wire includes the following steps:

[0084] S1, 45 parts of iron, 18 parts of electrolytic nickel plate, 6 parts of high-purity molybdenum powder, 4 parts of nano-tungsten powder, 3 parts of vanadium nitride alloy, and 1.2 parts of niobium iron alloy were put into the melting furnace and vacuumed to 5×10 -3 Pa, heating to 1650 ° C and holding for 30 minutes, and simultaneously adding 0.3 parts of lanthanum-cerium mixed rare earth and 0.15 parts of boron iron alloy for deoxidation;

[0085] S2, argon protection centrifugal atomization (pressure 10MPa, temperature 1500℃) to produce pre-alloyed powder with a particle size of 50-150μm;

[0086] S3, dry-mix the pre-alloyed powder with 0.8 parts of aluminum-magnesium alloy powder, 0.2 parts of magnesium-calcium alloy, and 0.1 parts of titanium hydride powder by ball milling for 2 hours (120 rpm, argon protection) to obtain a mixed powder;

[0087] S4: The mixed powder is placed in a soft-pack mold and is subjected to hot isostatic pressing (250 MPa for 10 minutes) to obtain a density of 7.8 g / cm 3 The blank;

[0088] S5. Sintering and hot extruding the green body to obtain a rod; wherein, sintering: low temperature section 800°C, heat preservation for 1 hour → high temperature section 1250°C, heat preservation for 2 hours (hydrogen partial pressure 0.05 MPa); hot extrusion to Φ8 mm rod (1100°C, extrusion ratio 12:1), spraying nano-graphite lubricant (the thickness of the sprayed lubricant is 2 μm).

[0089] S6. Drawing and annealing the rod to obtain welding wire; hot extruding to Φ8 mm rod (1100° C., extrusion ratio 12:1), spraying nanographite lubricant (2 μm); drawing to Φ3.2 mm in four passes in step S6 (reduction rate ≤20%, speed 8 m / min, lubricant concentration 8%); annealing every two passes (650° C., 30 s + 480° C., 60 s); and finally drawing to Φ1.2 mm (reduction rate ≤8%, speed 4 m / min, nitrogen cooling);

[0090] S7, electroplating a dense copper layer with a thickness of 0.5-1μm on the surface of the welding wire (3A / dm 2, 35°C, 0.5μm), to obtain a copper-plated welding wire; the copper-plated welding wire was placed in a nitrogen atmosphere (5% oxygen) and kept at 450°C for 10 minutes to form an Al2O3-MgO passivation film on the surface of the copper-plated welding wire.

[0091] S8. Depositing a molybdenum disulfide layer with a thickness of 0.1 μm on the surface of the passivation film of the copper-plated welding wire by magnetron sputtering (200 W, 20 sccm).

[0092] The diameter fluctuation of the welding wire of Example 1 was monitored in real time using a laser diameter gauge. The results showed that the diameter fluctuation of the welding wire had an error of ±2 μm. The wire was vacuum packaged (-0.09 MPa, nitrogen dew point ≤-40°C).

[0093] Example 2

[0094] The welding wire material composition of this example is shown in Table 1. In this embodiment, the composition includes 52 parts of iron, 22 parts of electrolytic nickel plate, 8 parts of high-purity molybdenum powder, 6 parts of nano-tungsten powder, 4.5 parts of vanadium nitride alloy, and 1.8 parts of niobium iron alloy. The other process parameters are the same as those in Example 1.

[0095] Example 3

[0096] The welding wire material composition of this example is shown in Table 1. In this embodiment, the composition includes 48.5 parts of iron, 20 parts of electrolytic nickel plate, 7 parts of high-purity molybdenum powder, 5 parts of nano-tungsten powder, 3.75 parts of vanadium nitride alloy, and 1.5 parts of niobium iron alloy. The other process parameters are the same as those in Example 1.

[0097] Example 4

[0098] The welding wire material composition of this example is the same as that of Example 1, as shown in Table 1. In this example, the high-temperature sintering stage is adjusted to 1300°C×2 hours (hydrogen partial pressure 0.1 MPa), and other process parameters are the same as those of Example 1.

[0099] Example 5

[0100] The welding wire material composition of this example is the same as that of Example 1, as shown in Table 1. In this example, the thickness of the electroplated copper layer is adjusted to 1 μm (current density 5 A / dm²), and other process parameters are the same as those of Example 1.

[0101] Table 1 Welding wire formula components of Examples 1-5

[0102]

[0103] Comparative Example 1

[0104] In this comparative example, the material composition of the welding wire is as shown in Table 2, 40 parts of iron, 15 parts of electrolytic nickel plate, and 5 parts of high-purity molybdenum powder. The other group formulas and processes are the same as those in Example 1.

[0105] Comparative Example 2

[0106] In the present comparative example, the material composition of the welding wire is shown in Table 2, iron 55 parts, electrolytic nickel plate 25 parts, nano-tungsten powder 7 parts, other components and processes are the same as Example 1.

[0107] Comparative Example 3

[0108] In the present comparative example, the material composition of the welding wire is the same as Example 1, as shown in Table 2, the sintering low-temperature section temperature is adjusted to 750°C, and the holding time is 1 hour, the aluminum-magnesium alloy diffusion is not activated, and the others are the same as Example 1.

[0109] Comparative Example 4

[0110] In the present comparative example, the material composition of the welding wire is the same as Example 1, as shown in Table 2, the final drawing speed is adjusted to 8 m / min, and there is no nitrogen cooling, and the others are the same as Example 1.

[0111] Comparative Example 5

[0112] In the present comparative example, the material composition of the welding wire is the same as Example 1, as shown in Table 2, the magnetron sputtering power is adjusted to 350 W, and the thickness of the molybdenum disulfide layer is 0.3 μm, and the others are the same as Example 1.

[0113] Table 2 Formula components of welding wire of Comparative Examples 1-5

[0114]

[0115] In summary, the welding wire samples are prepared according to Examples 1-5 and Comparative Examples 1-5, and the hardness, wear rate, diffusible hydrogen content, dilution rate and electrode wear rate performance of the samples are tested according to the following test standards, specifically, the test process is as follows:

[0116] a. Hardness (HV0.3) test standard: according to GB / T4340.1-2009 Metallographic Hardness Test Part 1: Test Method:

[0117] In this test, the sample parameters of the welding wire are:

[0118] The sample is the cross section of the welding wire, which is inlaid, polished and polished to a mirror surface without scratches;

[0119] Test load 0.3 kgf (2.94 N), holding time 15 seconds;

[0120] Take 3 test points for each welding wire, take the average value, and the measurement accuracy of the indentation diagonal line length is ±0.5 μm;

[0121] b. Wear rate (mm³ / N·m) test standard: Based on ASTM G99-17 Pin-on-Disc Wear Test Standard Method:

[0122] In this test, the sample parameters of the welding wire are:

[0123] Sample size: Φ6mm×25mm cylinder, surface roughness Ra≤0.4μm;

[0124] Grinding material: tungsten carbide ball (diameter 6mm, hardness 2200HV);

[0125] Test conditions: load 50N, sliding speed 0.2m / s, total sliding distance 1000m;

[0126] The wear volume was calculated by a three-dimensional topography instrument (accuracy ± 0.01 μm) as the product of the cross-sectional area and length of the wear scar;

[0127] c. Diffusible hydrogen content (mL / 100g) test standard: Based on GB / T3965-2012 Determination of diffusible hydrogen in deposited metal (glycerol replacement method):

[0128] In this test, the sample parameters of the welding wire are:

[0129] Sample preparation: The welding wire was welded under CO2 gas protection to form a deposited metal block (size 10mm×10mm×50mm), and immediately cooled to room temperature after welding;

[0130] Test procedure: The sample is immersed in glycerol at 45°C for 48 hours, and the volume of hydrogen released is measured using a gas collection device;

[0131] Environmental control: laboratory humidity ≤ 40%, temperature 25±1℃;

[0132] d. Dilution rate (%) test standard: Based on ISO17637:2016 Non-destructive testing of welds - Macroscopic metallographic examination of fusion welds:

[0133] In this test, the sample parameters of the welding wire are:

[0134] Sample preparation: welding wire was used to build up a single weld on the surface of low carbon steel base material (Q235), and the cross section was cut after welding;

[0135] Metallographic treatment: After etching with 4% nitric acid, the ratio of the fusion zone width to the deposited metal height was measured under a microscope;

[0136] e. Test standard for contact tip wear rate (mm / 100h): Based on actual working conditions simulation test, refer to "JB / T11722-2013 Technical Requirements for Welding Contact Tips":

[0137] In this test, the sample parameters of the welding wire are:

[0138] Test equipment: Robot welding workstation (current 280A, voltage 28V, wire feeding speed 8m / min);

[0139] Contact tip specifications: chromium zirconium copper material, inner diameter 1.2mm (initial accuracy ±0.01mm);

[0140] Wear measurement: After every 20 hours of welding, use an inside micrometer (accuracy ±0.001mm) to measure the change in the inside diameter of the conductive tip and calculate the accumulated wear over 100 hours.

[0141] The performance test data of the welding wires prepared in Examples 1-5 and Comparative Examples 1-5 were recorded respectively. The results are shown in Tables 3 and 4.

[0142] Table 3 Welding wire performance results of Examples 1-5

[0143]

[0144] Table 4 Performance results of welding wires of comparative examples 1-5

[0145]

[0146] According to the data in Tables 1, 2, 3, and 4, when the component contents of Examples 1-5 of the present invention were within the ranges given above, the diffusible hydrogen content was ≤2.1 mL / 100 g. However, when the component contents in Comparative Example 1 were lower, insufficient matrix strength led to increased hydrogen embrittlement sensitivity. The dilution rate of 9% in Example 1 was significantly lower than the 18% in Comparative Example 1, demonstrating that a nickel content of ≥18% can effectively inhibit parent metal mixing. While Comparative Example 2 achieved a hardness of 460 HV, the dilution rate was only 6%. The excessive nickel content resulted in poor molten pool fluidity and prone to incomplete fusion defects during actual welding. The lower sintering temperature in Comparative Example 3 did not activate the diffusion of the aluminum-magnesium alloy, potentially resulting in insufficient bonding between alloying elements and a less dense and uniform microstructure. This, in turn, made the wire more susceptible to material shedding during friction and wear, increasing the wear rate. Furthermore, increased internal defects in the material could affect the escape and capture of hydrogen, leading to an increase in the diffusible hydrogen content. Furthermore, structural defects also resulted in more severe wear of the contact tip during friction with the wire. In the final drawing speed of Comparative Example 4 without nitrogen cooling, a too fast drawing speed may cause more work hardening and residual stress to be generated inside the welding wire, and the organizational structure is not stable enough. This unstable organizational structure causes the welding wire to have a reduced performance during use and is more susceptible to wear. In Comparative Example 5, the excessively high magnetron sputtering power may cause changes in the microstructure of the molybdenum disulfide layer, such as excessive bombardment of the substrate resulting in poor interface bonding, or the destruction of the crystal structure of the molybdenum disulfide layer itself. An overly thick molybdenum disulfide layer may experience interlayer peeling, shedding, etc. during use, and cannot effectively play the role of friction reduction, thereby resulting in poor wear performance of the welding wire. In summary, the content range intervals of the welding wire material components and the rationality of the process parameter settings in Examples 1-5 of the present invention are known.

[0147] According to Tables 1 and 3, the combination of 45 parts of iron, 18 parts of nickel, and 6 parts of molybdenum in Example 1 of the present invention achieves an optimal balance between hardness and dilution rate. Combined with process dynamic annealing, the residual stress is controlled below 80 MPa, the probability of molten pool oscillation is reduced by 70%, and the composite coating of 0.5 μm copper layer, 50 nm aluminum oxide film, and 0.1 μm molybdenum disulfide layer has a conductive tip wear rate of only 0.008 mm / 100 h. Therefore, the welding wire and the preparation process thereof proposed in the present invention achieve the advantage of systematically optimizing the comprehensive performance of the welding wire. At the same time, Example 1 is the best embodiment of the present invention through reasonable component setting and process parameter matching.

[0148] The present disclosure proposes a welding wire and a preparation method, which have the following beneficial effects compared with the existing technology: the welding wire and the preparation process provided by the present invention have high reliability, long life and a wide process window, and are particularly suitable for robotic automated welding, surfacing welding of wear-resistant parts and high-strength steel connections in harsh environments, solving the problem in the existing technology of being difficult to strike a balance between wear resistance and low dilution.

[0149] It is understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present disclosure, and the present disclosure is not limited thereto. Those skilled in the art may make various modifications and improvements without departing from the spirit and substance of the present disclosure, and such modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A strong wear-resistant and low-dilution gas shielded welding wire, characterized in that: The welding wire is prepared from the following raw materials: 45-52 parts by weight of iron; 18-22 parts by weight of electrolytic nickel plate; 6-8 parts by weight of high-purity molybdenum powder; 4-6 parts by weight of nano-tungsten powder; 3-4.5 parts by weight of vanadium nitride alloy; 1.2-1.8 parts by weight of ferroniobium alloy; 0.8-1.5 parts by weight of aluminum-magnesium alloy powder; 0.3-0.6 parts by weight of lanthanum-cerium mixed rare earth; 0.15-0.25 parts by weight of ferroboron alloy; 0.5-0.8 parts by weight of metallic silicon powder; 0.2-0.4 parts by weight of magnesium-calcium alloy; 0.1-0.3 parts by weight of titanium hydride powder.

2. The strong wear-resistant and low-dilution gas shielded welding wire according to claim 1, characterized in that: The particle size of the nano tungsten powder is 200-400nm.

3. The strong wear-resistant and low-dilution gas shielded welding wire according to claim 1, characterized in that: The nitrogen content of the vanadium nitride alloy is 18-22%; and / or, The niobium content in the ferroniobium alloy is 60-65%; and / or, The magnesium content in the aluminum-magnesium alloy is 4-6%.

4. The strong wear-resistant and low-dilution gas shielded welding wire according to claim 1, characterized in that: The lanthanum-cerium mixed rare earth includes lanthanum oxide and cerium oxide, and the mass ratio of the lanthanum oxide to the cerium oxide is 7:

3.

5. A method for preparing the high wear-resistant and low-dilution gas shielded welding wire according to any one of claims 1 to 4, characterized in that: The method comprises: 45-52 parts by weight of iron, 18-22 parts by weight of electrolytic nickel plate, 6-8 parts by weight of high-purity molybdenum powder, 4-6 parts by weight of nano-tungsten powder, 3-4.5 parts by weight of vanadium nitride alloy, and 1.2-1.8 parts by weight of ferroniobium alloy are placed into a smelting furnace, subjected to heat preservation treatment, and then 0.3-0.6 parts by weight of lanthanum-cerium mixed rare earth and 0.15-0.25 parts by weight of ferroboron alloy are added for deoxidation and purification treatment to obtain a molten alloy liquid; The molten alloy liquid is subjected to centrifugal atomization treatment under argon protection to form pre-alloyed powder; The pre-alloyed powder is dry-mixed with 0.8-1.5 parts by weight of aluminum-magnesium alloy powder, 0.2-0.4 parts by weight of magnesium-calcium alloy, 0.5-0.8 parts by weight of metallic silicon powder, and 0.1-0.3 parts by weight of titanium hydride powder by ball milling to obtain a mixed powder; The mixed powder is placed in a soft-pack mold and subjected to hot isostatic pressing to obtain a green body; sintering and hot extruding the green body to obtain a rod; The rod is subjected to drawing and annealing treatments to obtain welding wire.

6. The method according to claim 5, characterized in that The green body is sintered using a two-stage sintering process of low temperature stage and high temperature stage. in, Low temperature section: 800-850℃ for 1 hour; High temperature section: 1250-1300℃ for 2 hours, hydrogen partial pressure 0.05-0.1MPa; The temperature of hot extrusion of the green body is 1100-1150° C., the extrusion ratio is 12:1, and during the hot extrusion process, a nano-graphite lubricant with a thickness of 2-5 μm is sprayed on the surface of the rod.

7. The method according to claim 5, characterized in that Four drawing passes are used, with a diameter reduction rate of ≤20% in each pass and a drawing speed of 8-12m / min. The diameter reduction rate of the last pass is ≤8% and the drawing speed is reduced to 4-6m / min. After every two drawing passes, annealing is carried out in a hydrogen protection annealing furnace.

8. The method according to claim 5, characterized in that The particle size of the pre-alloyed powder is 50-150 μm; and / or, The diameter of the rod is 7-9 mm; and / or, The diameter of the welding wire is 1-1.3 mm.

9. The method according to any one of claims 5 to 8, characterized in that: After the rod is subjected to drawing and annealing to obtain the welding wire, the method further comprises: Electroplating a dense copper layer with a thickness of 0.5-1 μm on the surface of the welding wire to obtain a copper-plated welding wire; The copper-plated welding wire is placed in a nitrogen atmosphere and kept warm at 450-500° C. for 8-12 minutes, so that an Al 2 O 3 -MgO passivation film is formed on the surface of the copper-plated welding wire.

10. The method according to claim 9, characterized in that After the copper-plated welding wire is subjected to heat preservation treatment, the method further comprises: A molybdenum disulfide layer with a thickness of 0.1-0.2 μm is deposited on the surface of the passivation film of the copper-plated welding wire by a magnetron sputtering method.

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