A flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant overlay welding of conveyor roller surface

Abstract

This invention relates to the field of welding materials technology, specifically to a flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing of conveyor rollers. The specific technical solution is as follows: a flux core, by mass percentage, comprises the following components: 10-20% graphite, 25-35% ferrotitanium, 2-6% ferrovanadium, 3-8% electrolytic manganese, 2-10% ferromolybdenum, 5-15% ferrosilicon, 2% aluminum-magnesium alloy, and the remainder being Fe powder. The flux-cored welding wire prepared by this invention, when used for arc surfacing, produces a welding alloy with excellent welding processability, aesthetically pleasing weld formation, and low surface porosity, as well as high hardness, high-temperature wear resistance, and corrosion resistance.

Description

Technical Field

[0001] This invention relates to the field of welding materials technology, and specifically to a flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant overlay welding of conveyor roller surfaces. Background Technology

[0002] In the entire steel production process, the conveyor roller system, as a key material handling device, undertakes the task of transporting materials from raw materials (including ore, sinter, and pellets) to semi-finished products (steel billets) and final products (various types of steel). By achieving continuous and stable material transfer between different production processes and equipment, this system not only ensures the continuity of the production process but also significantly improves overall production efficiency. Especially in hot strip rolling mills, the conveyor rollers, as core supporting equipment components, directly affect the operational efficiency of the production system. Therefore, optimizing the reliability of the conveyor roller system has significant engineering practical value for achieving efficient and high-quality production in steel enterprises.

[0003] In hot strip rolling production, the temperature of the strip material is typically maintained at around 600℃ after rolling. When the high-temperature strip passes through the conveyor rolls, forced water cooling is required to control its temperature. This results in the conveyor roll surface continuously enduring severe thermal cycling loads and oxidation corrosion reactions in a high-temperature, humid environment. Simultaneously, relative movement and contact pressure between the hot-rolled strip and the roll surface cause the outer diameter of the conveyor roll surface to continuously decrease. Therefore, these synergistic effects lead to surface cracking and reduced dimensional accuracy of the conveyor rolls, resulting in a high annual scrap rate, severely impacting production continuity and causing significant economic losses. Engineering practice shows that using surfacing welding technology to strengthen key parts of the conveyor rolls can significantly improve their high-temperature wear and corrosion resistance. By selecting appropriate surfacing materials and optimizing process parameters, the service life of the conveyor rolls can be significantly extended, resulting in good economic benefits.

[0004] Hardfacing, as an advanced surface repair and strengthening technology, plays a vital role in the remanufacturing of mechanical components. This technology not only precisely restores the geometry of worn parts, ensuring equipment operational accuracy, but also significantly improves the wear and corrosion resistance of component surfaces by selecting high-performance hardfacing materials, thereby extending equipment lifespan and reducing unplanned downtime losses due to premature failure. Currently, the mainstream wear-resistant hardfacing materials used in industrial applications can be divided into three main categories: cobalt-based, nickel-based, and iron-based, each with unique performance characteristics and application limitations. Cobalt-based hardfacing alloys exhibit excellent wear resistance and thermal stability at high temperatures, but they are expensive, prone to recrystallization cracks, and have complex welding processes. Nickel-based hardfacing alloys offer the best resistance to intermetallic friction and wear, and possess high high-temperature oxidation resistance, but they are costly and require extremely strict control of welding parameters. Iron-based hardfacing alloys are the most widely used type of hardfacing material; their hardfacing metals not only have excellent wear resistance but also offer good economic benefits. The microstructure of the iron-based weld overlay alloy is characterized by a high volume fraction of primary M7C3 carbide phases. The precipitation of these hard phases can significantly improve the hardness of the alloy, effectively resisting abrasive cutting and plastic deformation wear. At the same time, the hard phase network can significantly improve the material strength. However, due to the presence of large-sized primary M7C3 carbide phases, the fracture toughness of this material system is insufficient, and it is prone to crack initiation under high contact stress conditions. Furthermore, its corrosion resistance is poor.

[0005] The carbide-reinforced iron-chromium surfacing alloy provided by this invention is a novel wear-resistant surfacing material. It precipitates fine hard carbide phases (including TiC, NbC, MoC, VC, WC, etc.) on a martensitic matrix. Among these, TiC, due to its high hardness, excellent wear resistance, corrosion resistance, and thermal stability, is the most commonly used reinforcing phase in iron-based, titanium-based, and cobalt-based alloys. These dispersed TiC hard phases can significantly improve the alloy's hardness and wear resistance, extending the service life of the conveyor rollers. Simultaneously, the fine carbide particles increase the number of grain boundaries, making the Cr element distribution more uniform and promoting the formation of a continuous and dense Cr2O3 passivation film, thereby improving the alloy's corrosion resistance. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing welding of conveyor rollers. The surfacing alloy obtained by arc welding using the flux-cored welding wire provided by this invention not only has good surfacing processability, beautiful weld formation, and few surface pores, but also possesses high hardness, high-temperature wear resistance, and corrosion resistance.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] This invention discloses a core containing the following components by weight percentage:

[0009] Graphite 10-20%, ferrotitanium 25-35%, ferrovanadium 2-6%, electrolytic manganese 3-8%, ferromolybdenum 2-10%, ferrosilicon 5-15%, aluminum-magnesium alloy 2%, the remainder being Fe powder.

[0010] Preferably, by mass percentage, it comprises the following components: 15-20% graphite, 30-35% ferrotitanium, 2-5% ferrovanadium, 5-8% electrolytic manganese, 4-9% ferromolybdenum, 8-15% ferrosilicon, 2% aluminum-magnesium alloy powder, and the remainder being Fe powder.

[0011] Preferably, the titanium in the ferrotitanium is 70% by mass; the vanadium in the ferrovanadium is 50% by mass; the molybdenum in the ferromolybdenum is 60% by mass; the silicon in the ferrosilicon is 75% by mass; the manganese in the electrolytic manganese metal is greater than 90% by mass; the carbon in the graphite is greater than 99.5% by mass; and the aluminum-magnesium alloy has an aluminum content of 53%, a manganese content of 4%-7%, and the remainder is magnesium.

[0012] Preferably, the ferrotitanium has a particle size of 30-50 mesh; the ferromolybdenum and ferrovanadium both have a particle size of 80-100 mesh; the electrolytic manganese metal has a particle size of 60-80 mesh; the ferrosilicon has a particle size of 70-90 mesh; the graphite has a particle size of 40-60 mesh; the aluminum-magnesium alloy has a particle size of 60 mesh; and the Fe powder has a particle size of 100-150 mesh.

[0013] Accordingly, a flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant overlay welding of conveyor roller surface is provided, wherein the raw material of the flux-cored welding wire includes the flux core.

[0014] Preferably, the flux-cored wire has a flux-cored powder filling rate of 20-30%.

[0015] Correspondingly, a method for preparing a titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant flux-cored welding wire for overlay welding on the surface of a conveyor roller involves encasing the flux core in a metal shell.

[0016] Accordingly, a welding method for reducing welding porosity when using a titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing flux-cored wire for surfacing the surface of a conveyor roller is provided. The welding is performed using the titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing flux-cored wire for surfacing the surface of the conveyor roller prepared by the aforementioned preparation method; the welding process is an arc surfacing process.

[0017] Preferably, the arc welding process parameters are: voltage 20-30V; current 250-380A; wire feeding speed 7-8m / min; atmosphere: 80%Ar+20%CO2 mixture, gas flow rate: 10-20L / min, and the length of the welding wire extending out of the contact tip is 15-25mm.

[0018] Preferably, after welding, the mass percentage of alloying elements in the obtained weld overlay alloy is within the following range: C: 3-10%; Cr: 5-20%; Ti: 2-15%; V: 0.5-3%; Al: 0.5-1%; Mn: 0.5-5%; Si: 1-5%; Mo: 0.5-5%; Fe: balance.

[0019] The present invention has the following beneficial effects:

[0020] The present invention provides a flux-cored welding wire for titanium carbide reinforced iron-based wear-resistant and corrosion-resistant surfacing welding of conveyor rollers, which meets the performance requirements of new high-temperature wear-resistant and corrosion-resistant materials, satisfying high hardness and excellent high-temperature wear resistance while also possessing good corrosion resistance. Attached Figure Description

[0021] Figure 1 SEM image of the microstructure of the weld overlay alloy in Example 5;

[0022] Figure 2 This is a high-temperature friction and wear morphology image of the weld overlay alloy in Example 5;

[0023] Figure 3 The surface morphology of the weld overlay alloy in Example 5 at 600°C under friction and wear conditions. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Unless otherwise specified, the technical means used in the implementation examples are conventional means well known to those skilled in the art.

[0026] 1. This invention discloses a core containing the following components by weight percentage:

[0027] Graphite 10-20%, ferrotitanium 25-35%, ferrovanadium 2-6%, electrolytic manganese 3-8%, ferromolybdenum 2-10%, ferrosilicon 5-15%, aluminum-magnesium alloy 2%, the remainder being Fe powder.

[0028] Furthermore, by mass percentage, it includes the following components: 12-20% graphite, 28-35% ferrotitanium, 2-5.5% ferrovanadium, 4-8% electrolytic manganese, 3-9% ferromolybdenum, 7-15% ferrosilicon, 2% aluminum-magnesium alloy, and the remainder being Fe powder.

[0029] Furthermore, the titanium in the ferrotitanium is 70% by mass; the vanadium in the ferrovanadium is 50% by mass; the molybdenum in the ferromolybdenum is 60% by mass; the silicon in the ferrosilicon is 75% by mass; the manganese in the electrolytic manganese metal is greater than 90% by mass; the carbon in the graphite is greater than 99.5% by mass; and the aluminum-magnesium alloy has an aluminum content of 53%, a manganese content of 4%-7%, and the remainder is magnesium.

[0030] Furthermore, the particle size of the ferrotitanium is 30-50 mesh; the particle size of the ferromolybdenum and ferrovanadium is 80-100 mesh; the particle size of the electrolytic manganese is 60-80 mesh; the particle size of the ferrosilicon is 70-90 mesh; the particle size of the graphite is 40-60 mesh; the particle size of the aluminum-magnesium alloy is 60 mesh; and the particle size of the Fe powder is 100-150 mesh.

[0031] 2. This invention discloses a flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing of conveyor rollers. The raw material of the flux-cored welding wire includes the aforementioned flux core. The filling rate of the flux core powder in the flux-cored welding wire is 20-30%, that is, the percentage of the area occupied by the flux core to the total cross-sectional area of ​​the welding wire, preferably 24-30%, more preferably 24-26%.

[0032] 3. This invention discloses a method for preparing a titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant flux-cored welding wire for overlay welding on the surface of a conveyor roller, wherein the flux core is encased in a metal shell.

[0033] Specifically, the following steps are included:

[0034] (1) Powder selection and drying: Select alloy powders according to the above-mentioned core composition, and dry each powder in advance. The drying equipment is a vacuum drying oven, the drying temperature is 150℃, and the drying time is 2 hours.

[0035] (2) Sieving: In order to ensure the consistency of particle size of the same powder, each powder needs to be sieved through a sieve.

[0036] (3) Powder preparation and mixing: Powder preparation is carried out according to the number of kilograms, filling rate and mass percentage of each type of flux-cored wire. After preparation, the different powders need to be mixed evenly to ensure that the components in the flux-cored wire are uniform.

[0037] (4) Selecting the strip: Select stainless steel strip as the metal shell. The thickness of the strip is 0.3mm and the width is 12mm.

[0038] (5) Drawing: The steel strip passes through the forming rollers and changes from a plane to a U-shape. At this time, the pre-prepared core powder is fed into the U-shaped steel strip through the conveyor belt. After the U-shaped steel strip carrying the powder passes through the closing rollers, the steel strip changes from a U-shape to an O-shape, and the steel strip closes, tightly wrapping the core powder.

[0039] (6) Diameter reduction and packaging: The drawn flux-cored wire is passed through a drawing die of a certain diameter to finally achieve the diameter required for the finished product. The reduced-diameter flux-cored wire is then loaded into an I-beam and sealed for storage until use.

[0040] 4. This invention discloses a welding method for reducing welding porosity when using a titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing flux-cored wire for surfacing the surface of a conveyor roller. The welding is performed using the titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing flux-cored wire prepared by the aforementioned method. The welding process is an arc surfacing process. The arc surfacing process parameters are: voltage 20-30V; current 250-380A; wire feed speed 7-8m / min; atmosphere: 80%Ar + 20%CO2 mixture, gas flow rate: 10-20L / min; wire extension length from the contact tip 15-25mm.

[0041] Furthermore, after welding, the mass percentage of alloying elements in the obtained weld overlay alloy is within the following range: C: 3-10%; Cr: 5-20%; Ti: 2-15%; V: 0.5-3%; Al: 0.5-1%; Mn: 0.5-5%; Si: 1-5%; Mo: 0.5-5%; Fe: balance.

[0042] In this invention, the various elements function as follows:

[0043] Ti: Exhibits excellent corrosion resistance, forming a robust and stable titanium oxide film on its surface. It exhibits good corrosion resistance in many corrosive media, particularly excelling in high-temperature, high-pressure, and highly corrosive environments. Simultaneously, Ti refines the grain size of the weld metal, improving weld strength and toughness, and enhancing the performance of the welded joint. Ti has a strong affinity for elements such as carbon in steel, forming stable carbides. These compounds act as heterogeneous nucleation sites during the solidification of molten steel, increasing the nucleation rate and refining the grain size. This refined grain size improves the overall mechanical properties of the material, including strength, toughness, and plasticity.

[0044] C: Carbon and chromium are alloying elements that significantly affect the microstructure of high-chromium cast iron. As the mass fraction of carbon and chromium increases, the microstructure of high-chromium cast iron transforms from hypoeutectic to hypereutectic, and the primary phase changes from austenite to M7C3 carbides. These hard phases have high hardness and can significantly improve the wear resistance of the weld overlay.

[0045] Cr: Chromium plays a decisive role in the type of carbide, mainly M3C, M7C3, and M. 23C6 carbides and M7C3 carbides are ideal carbides. Cr is a solid solution strengthening element and a strong carbide-forming element. Chromium reacts with carbon to form M7C3 carbides, which have extremely high hardness and are uniformly distributed in the matrix, significantly improving the material's hardness and wear resistance. Simultaneously, they can form a dense oxide film on the metal surface, which prevents further contact between the metal and external corrosive media, thereby improving corrosion resistance.

[0046] Mo: Molybdenum can not only improve the hardenability of alloys and promote the formation of ferrite and martensite, but also play a role in solid solution strengthening, improving the hardness and wear resistance of alloys.

[0047] Vanadium is a strong carbide-forming element, capable of forming carbides. These carbides have small particle sizes and are dispersed in the alloy, playing a role in grain refinement and dispersion strengthening. Vanadium's solid solution in austenite increases the tendency of supercooled austenite to transform into martensite, promoting martensite formation.

[0048] Mn and Si: The elemental transition coefficient is improved by using manganese-silicon combined deoxidation.

[0049] Fe: Filling the gap.

[0050] To better understand the present invention, the present invention will be further described below with reference to specific embodiments, but the content of the present invention is not limited to the following embodiments.

[0051] The common parts in each embodiment are as follows:

[0052] In the following embodiments, all raw materials used are commercially available.

[0053] In the following embodiments, the outer sheath of the flux-cored wire is made of stainless steel strip with a thickness of 0.3 mm and a width of 12 mm. The flux composition of the flux-cored wire is specifically described in the embodiments. After passing through the rollers, the steel strip is rolled into a U-shape. The various powders in the formula are weighed in advance according to the designed proportions, dried, and mixed evenly before being mechanically added to the steel strip. The U-shaped steel strip closes after passing through subsequent rollers. The closed steel strip is repeatedly drawn and reduced in diameter using a drawing die to produce a flux-cored wire with a diameter of 1.6 mm, which is the flux-cored wire for the conveyor roller.

[0054] In the core powder, the ferrotitanium has a particle size of 30-50 mesh; the ferromolybdenum and ferrovanadium both have a particle size of 80-100 mesh; the manganese has a particle size of 60-80 mesh; the ferrosilicon has a particle size of 70-90 mesh; the graphite has a particle size of 40-60 mesh; and the Fe powder has a particle size of 100-150 mesh.

[0055] The titanium-iron powder contains 70% titanium by mass; the molybdenum-iron powder contains 60% molybdenum by mass; the silicon-iron powder contains 75% silicon by mass; the vanadium-iron powder contains 50% vanadium by mass; the electrolytic manganese metal contains more than 90% manganese by mass; and the graphite contains more than 99.5% carbon by mass.

[0056] The surfacing alloy was prepared by arc welding with 80% Ar + 20% CO2 mixed gas shielding. The welding process parameters were as follows: voltage: 20-30V; current: 250-380A; wire feed speed: 7-8m / min; atmosphere: 80% Ar + 20% CO2 mixed gas; gas flow rate: 10-20L / min; and the length of the welding wire extending out of the contact tip: 15-25mm.

[0057] The hardness, friction and wear, and electrochemical corrosion tests were conducted on the weld overlay alloys prepared in the following embodiments to simulate the actual working conditions of the conveyor rollers. The specific test steps are as follows:

[0058] (1) The Rockwell hardness of the weld overlay alloy was tested using an HR-150A electric Brinell hardness tester. The hardness tester indenter was a diamond cone indenter, with a load of 150 kg, a loading time of 5 s, and a recovery time of 3 s. The distance between two adjacent test points was 5 mm, and the number of test points was 10. The final hardness of the weld overlay alloy was taken as the average value of the data from the 10 test points.

[0059] (2) High-temperature friction and wear tests were conducted using an MS-HT1000 high-temperature friction and wear testing machine. The wear specimen size was 20mm×20mm×7mm. The test parameters were: φ4 silicon carbide, load 2000g, friction radius 6mm, rotation speed 300r / min, test temperature 600℃, and test time 60min. To reduce experimental error, each specimen was tested three times. After the test, the cross-sectional area of ​​the wear track was measured using a Hömmel T8000 profilometer to characterize the excellent wear resistance.

[0060] (3) Electrochemical tests were conducted using a PMCCHS08A electrochemical workstation in a three-electrode system. The working electrode was a weld overlay alloy, the reference electrode was a saturated calomel solution, and the auxiliary electrode was a platinum sheet electrode. For the actual operating conditions of the conveyor roller, a 1M H₂SO₄ solution was selected as the corrosion medium to simulate its corrosion behavior under service conditions. The testing process began by stabilizing the working electrode at the open circuit potential (OCP) for 300 seconds to ensure electrode stability. Subsequently, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PVP) tests were performed. In the EIS test, the frequency range was set to 10... -2 Up to 10 5The electrochemical behavior of the electrode at different frequencies was evaluated using an AC perturbation voltage of 10 mV at a frequency of -0.3 to 2 V. The potentiodynamic polarization test was performed from cathode to anode at a scan rate of 1 mV / s. To ensure the reliability of the test data, each test was performed in at least three parallel experiments. These electrochemical tests provide a comprehensive evaluation of the electrochemical performance of the weld overlay alloy.

[0061] Example 1

[0062] Weigh the core according to the following percentages: 20% graphite, 28% ferrotitanium, 4% ferrovanadium, 4% electrolytic manganese, 3% ferromolybdenum, 7% ferrosilicon, 2% aluminum-magnesium alloy powder, and the remainder is Fe powder.

[0063] The welding alloy was prepared according to the above welding process. The mass percentage of alloying elements in the obtained welding alloy was C: 5.3%; Cr: 14.4%; Ti: 4%; V: 0.5%; Al: 0.7%; Mn: 1%; Si: 1.2%; Mo: 0.5%; Fe and unavoidable impurities: balance.

[0064] The Rockwell hardness of the weld overlay alloy is 51 HRC; the cross-sectional area of ​​the wear track at 600℃ is 0.1513 mm. 2 Electrochemical corrosion is quite severe, with a corrosion potential of -612.21 mV and a corrosion current density of 2.58 × 10⁻⁶ mV. -4 μA / cm 2 .

[0065] Example 2

[0066] Weigh the core according to the following percentages: 20% graphite, 30% ferrotitanium, 4% ferrovanadium, 6% electrolytic manganese, 5% ferromolybdenum, 10% ferrosilicon, 2% aluminum-magnesium alloy powder, and the remainder is Fe powder.

[0067] The welding alloy prepared according to the welding process disclosed above in this invention has the following mass percentage content of alloying elements: C: 5.3%; Cr: 14.4%; Ti: 4.8%; V: 0.5%; Al: 0.7%; Mn: 1.5%; Si: 1.8%; Mo: 0.8%; Fe and unavoidable impurities: balance.

[0068] The Rockwell hardness of the weld overlay alloy is 54.3 HRC; the cross-sectional area of ​​the wear track at 600℃ is 0.1174 mm. 2 Electrochemical corrosion is quite severe, with a corrosion potential of -481.01 mV and a corrosion current density of 1.11 × 10⁻⁶ mV. -4 μA / cm 2 .

[0069] Example 3

[0070] Weigh the core according to the following percentages: 20% graphite, 30% ferrotitanium, 5% ferrovanadium, 6% electrolytic manganese, 6.5% ferromolybdenum, 12% ferrosilicon, 2% aluminum-magnesium alloy powder, and the remainder is Fe powder.

[0071] The welding alloy prepared according to the welding process disclosed above in this invention has the following mass percentage content of alloying elements: C: 5.3%; Cr: 14.4%; Ti: 4.8%; V: 1.0%; Al: 0.7%; Mn: 2.8%; Si: 2.3%; Mo: 1.0%; Fe and unavoidable impurities: balance.

[0072] The Rockwell hardness of the weld overlay alloy is 57.0 HRC; the cross-sectional area of ​​the wear track at 600℃ is 0.0762 mm. 2 Electrochemical corrosion is quite severe, with a corrosion potential of -265.42 mV and a corrosion current density of 5.90 × 10⁻⁶ mV. -5 μA / cm 2 .

[0073] Example 4

[0074] Weigh the core according to the following percentages: 20% graphite, 35% ferrotitanium, 5% ferrovanadium, 6.5% electrolytic manganese, 8% ferromolybdenum, 15% ferrosilicon, 2% aluminum-magnesium alloy powder, and the remainder is Fe powder.

[0075] The welding alloy prepared according to the welding process disclosed above in this invention has the following mass percentage content of alloying elements: C: 5.3%; Cr: 14.4%; Ti: 6.1%; V: 1.0%; Al: 0.7%; Mn: 2.8%; Si: 3%; Mo: 1.2%; Fe and unavoidable impurities: balance.

[0076] The welding process produces almost no spatter, and the weld alloy surface exhibits high smoothness and minimal micro-cracks. The Rockwell hardness of the weld alloy is 60.2 HRC; the cross-sectional area of ​​the wear track at 600℃ is 0.0495 mm². 2 Electrochemical corrosion is quite severe, with a corrosion potential of -87.11 mV and a corrosion current density of 1.38 × 10⁻⁶ mV. -6 μA / cm 2 .

[0077] Example 5

[0078] Weigh the core according to the following percentages: 18% graphite, 35% ferrotitanium, 5.5% ferrovanadium, 8% electrolytic manganese, 9% ferromolybdenum, 15% ferrosilicon, 2% aluminum-magnesium alloy powder, and the remainder is Fe powder.

[0079] The welding alloy prepared according to the welding process disclosed above in this invention has the following mass percentage content of alloying elements: C: 4.6%; Cr: 14.5%; Ti: 7.0%; V: 0.8%; Al: 0.8%; Mn: 2.1%; Si: 2.6%; Mo: 1.5%; Fe and unavoidable impurities: balance.

[0080] The welding process produces minimal spatter, and the weld alloy surface is free of porosity, exhibiting high flatness and no cracks (e.g.) Figure 1 As shown), the microstructure of the weld overlay alloy consists of martensite, austenite, and carbide TiC (as shown). Figure 2 (As shown).

[0081] The Rockwell hardness of the weld overlay alloy is 61.6 HRC; the cross-sectional area of ​​the wear track at 600℃ is 0.0474 mm. 2 (like Figure 3 (As shown); the electrochemical corrosion is relatively mild, with a corrosion potential of -0.76mV and a corrosion current density of 8.24×10⁻⁶. -6 μA / cm 2 .

[0082] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant overlay welding on the surface of a conveyor roller, characterized in that: The drug core is encased in a metal shell, with stainless steel strip selected as the metal shell. The drug core comprises the following components by weight percentage: Graphite 10-20%, ferrotitanium 25-35%, ferrovanadium 2-6%, electrolytic manganese 3-8%, ferromolybdenum 2-10%, ferrosilicon 5-15%, aluminum-magnesium alloy 2%, the remainder being Fe powder; The titanium-iron alloy contains 70% titanium by mass; the vanadium-iron alloy contains 50% vanadium by mass; the molybdenum-iron alloy contains 60% molybdenum by mass; the silicon-iron alloy contains 75% silicon by mass; the electrolytic manganese metal contains more than 90% manganese by mass; the graphite contains more than 99.5% carbon by mass; the aluminum-magnesium alloy contains 53% aluminum by mass, 4%-7% manganese, and the remainder is magnesium. The ferrotitanium has a particle size of 30-50 mesh; the ferromolybdenum and ferrovanadium both have a particle size of 80-100 mesh; the electrolytic manganese metal has a particle size of 60-80 mesh; the ferrosilicon has a particle size of 70-90 mesh; the graphite has a particle size of 40-60 mesh; the aluminum-magnesium alloy has a particle size of 60 mesh; and the Fe powder has a particle size of 100-150 mesh.

2. The flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant overlay welding of conveyor rollers according to claim 1, characterized in that: The core comprises, by weight percentage, the following components: 15-20% graphite, 30-35% ferrotitanium, 2-5% ferrovanadium, 5-8% electrolytic manganese, 4-9% ferromolybdenum, 8-15% ferrosilicon, 2% aluminum-magnesium alloy powder, and the remainder being Fe powder.

3. The flux-cored welding wire for titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant overlay welding of conveyor rollers according to claim 1 or 2, characterized in that: The raw material of the flux-cored welding wire includes the flux core, and the flux core powder filling rate in the flux-cored welding wire is 20-30%.

4. A welding method for reducing weld porosity when using titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing wire on the surface of a conveyor roller, characterized in that: The welding is performed using the titanium carbide-reinforced iron-based wear-resistant and corrosion-resistant surfacing welding wire as described in any one of claims 1-3; the welding process is an electric arc welding process; the electric arc welding process parameters are: voltage 20-30V. Current 250-380A; wire feeding speed 7-8m / min; Atmosphere: 80% Ar + 20% CO2 mixture, gas flow rate: 10-20 L / min, welding wire extension length from the contact tip: 15-25 mm; After welding, the mass percentage of alloying elements in the obtained weld overlay alloy is within the following range: C: 3-10%; Cr: 5-20%; Ti: 2-15%; V: 0.5-3%; Al: 0.5-1%; Mn: 0.5-5%; Si: 1-5%; Mo: 0.5-5%; Fe: balance.

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