Composite carbide reinforced single-tooth roller surface high-temperature wear-resistant flux-cored wire

Abstract

The invention relates to the technical field of welding materials, in particular to a composite carbide reinforced single-tooth roller surface high-temperature wear-resistant flux-cored wire. According to the specific technical scheme, the flux core is prepared from, by mass, 5%-10% of graphite, 20%-50% of high-carbon ferrochrome, 2%-5% of silicon carbide, 2%-6% of tungsten carbide, 1%-4% of electrolytic manganese, 10%-20% of ferrocolumbium, 3%-7% of ferrovanadium, 15%-25% of ferromolybdenum and the balance Fe powder. According to the flux-cored wire prepared through the flux core, the surfacing alloy obtained through electric arc surfacing is good in surfacing manufacturability, attractive in weld joint forming and small in surface air hole number, and the flux-cored wire has high hardness and high-temperature abrasion resistance.

Description

Technical Field

[0001] The invention relates to the technical field of welding materials, in particular to a high-temperature wear-resistant flux-cored welding wire with a composite carbide-reinforced single-tooth roller surface. Background Art

[0002] As a key piece of equipment in the modern steel industry's sintering process, the single-tooth roller crusher primarily crushes high-temperature sintering materials (typically operating at 800-900°C). Under extreme operating conditions of sustained high temperatures and high wear, the equipment's core components often suffer from severe high-temperature wear, significantly shortening their service life. To effectively address this issue, advanced surface treatment technologies are employed to repair and strengthen vulnerable components. This not only significantly extends the equipment's service life but also prevents premature machine failure, significantly reducing production and maintenance costs.

[0003] High-chromium iron-based cemented carbide (Cr: 12-30wt.%, C: 2.0-4.0wt.%) is widely used due to its excellent cost-effectiveness and wear resistance. In this alloy system, martensite and retained austenite together form a matrix structure with both strength and toughness, while M7C3 carbides (M=Cr, Fe) generated by the reaction of elements such as Cr and Fe with C provide critical hardness and wear resistance. However, for the complex working conditions of single-tooth roller components, traditional Fe-Cr-C alloys have obvious limitations: the coarse primary M7C3 carbides have a weak bond with the matrix interface, which can easily cause cracking and spalling of the weld overlay, seriously affecting the service life of the components.

[0004] To this end, the present invention has developed a multi-element alloyed carbide-reinforced iron-chromium alloy. High-melting-point elements such as Nb, W, and Mo are added to the flux-cored welding wire to form a multi-component carbide hard phase, which can, on the one hand, enhance the wear resistance of the alloy, and on the other hand, refine the M7C3, thereby improving the surfacing formability and interface bonding strength. The carbides formed by Nb and C can refine the grains and improve the high-temperature stability and wear resistance of the alloy; W can maintain good strength and hardness and is not prone to deformation and wear; Mo has good high-temperature strength and creep resistance and can form a dense oxide film at high temperatures. This oxide film can prevent further oxidation and wear, thereby improving the material's resistance to high-temperature wear; and V is a strong carbide-forming element that can form carbides. This type of carbide has a small particle size and is dispersed in the alloy, which plays a role in fine grain strengthening and dispersion strengthening. This alloy system significantly improves the service life of single-tooth rollers under high-temperature wear conditions. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention provides a high-temperature wear-resistant flux-cored welding wire with a composite carbide reinforced single-tooth roller surface. The surfacing alloy obtained by arc surfacing with the provided flux-cored welding wire not only has good surfacing processability, beautiful weld formation, and a small number of surface pores, but also has high hardness and high-temperature wear resistance.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0007] The present invention discloses a drug core, which comprises the following components in percentage by mass:

[0008] Graphite 5-10%, high carbon ferrochrome 20-50%, silicon carbide 2-5%, tungsten carbide 2-6%, electrolytic manganese 1-4%, ferroniobium 10-20%, ferrovanadium 3-7%, ferromolybdenum 15-25%, and the rest is Fe powder.

[0009] Preferably, the following components are included in percentage by mass: 6-9% graphite, 25-46% high carbon ferrochrome, 3-4% silicon carbide, 3-5% tungsten carbide, 2-4% electrolytic manganese, 10-19% ferroniobium, 4-6% ferrovanadium, 15-20% ferromolybdenum, and the rest is Fe powder.

[0010] Preferably, the mass fraction of chromium in the high-carbon ferrochrome is 68%, and the mass fraction of carbon is 8%; the mass fraction of silicon in the silicon carbide is 70%, and the mass fraction of carbon is 30%; the mass fraction of tungsten in the tungsten carbide is 94%, and the mass fraction of carbon is 6%; the mass fraction of niobium in the ferroniobium is 65%; the mass fraction of vanadium in the ferrovanadium is 50%; the mass fraction of molybdenum in the ferromolybdenum is 60%; the mass fraction of manganese in the electrolytic manganese is greater than 90%; and the mass fraction of carbon in the graphite is greater than 99.5%.

[0011] Preferably, the particle size of the high carbon ferrochrome is 30-50 mesh; the particle sizes of the tungsten carbide, ferroniobium, ferromolybdenum and ferrovanadium are all 80-100 mesh; the particle size of the electrolytic manganese is 60-80 mesh; the particle size of the silicon carbide is 70-90 mesh; the particle size of the graphite is 40-60 mesh; and the particle size of the Fe powder is 100-150 mesh.

[0012] Correspondingly, a composite carbide reinforced single tooth roller surface high temperature wear-resistant flux-cored welding wire, the raw material of the flux-cored welding wire includes the flux core.

[0013] Preferably, the filling rate of the flux core in the flux-cored welding wire is 40-60%.

[0014] Accordingly, a method for preparing a high-temperature wear-resistant flux-cored welding wire with a composite carbide-reinforced single-tooth roller surface comprises wrapping the flux core described in the above scheme with a metal shell.

[0015] Correspondingly, a welding method using a composite carbide reinforced single tooth roller surface high temperature wear-resistant flux-cored welding wire is provided, wherein welding is performed using the composite carbide reinforced single tooth roller surface high temperature wear-resistant flux-cored welding wire prepared by the preparation method, and the welding process is an arc surfacing process.

[0016] Preferably, the arc surfacing process parameters are: voltage: 25-30V, current: 380-480A, wire feeding speed: 1000mm / min, length of the welding wire extending from the conductive nozzle: 15-25mm.

[0017] Preferably, after welding is completed, the mass percentage of alloying elements in the obtained surfacing alloy is within the following ranges: C: 3-6%; Cr: 15-30%; Si: 0.5-2%; W: 1-3%; Mn: 0.5-3%; Nb: 2-8%; V: 1.0-3.0%; Mo: 4-6%; Fe and unavoidable impurities: balance.

[0018] The present invention has the following beneficial effects:

[0019] The alloy produced by arc hardfacing with the high-temperature, wear-resistant flux-cored wire of the present invention on the surface of a single-tooth roller consists of martensite, retained austenite, and carbides (M7C3, NbC, etc.). The M7C3 carbide is the primary wear-resistant phase in the alloy, effectively improving the wear resistance of the hardfacing alloy. NbC acts as a heterogeneous nucleation site for the M7C3 carbide, refining the M7C3. This significantly improves the high-temperature wear resistance of the hardfacing alloy and extends the service life of the single-tooth roller. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the surface morphology of the surfacing alloy prepared in Example 5;

[0021] Figure 2 This is the wear depth diagram of the surfacing alloy prepared in Example 5. DETAILED DESCRIPTION

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0024] 1. The present invention discloses a drug core comprising the following components in percentage by mass:

[0025] Graphite 5-10%, high carbon ferrochrome 20-50%, silicon carbide 2-5%, tungsten carbide 2-6%, electrolytic manganese 1-4%, ferroniobium 10-20%, ferrovanadium 3-7%, ferromolybdenum 15-25%, and the rest is Fe powder.

[0026] Furthermore, the core disclosed in the present invention comprises the following components, calculated by mass percentage: 6-9% graphite, 25-46% high carbon ferrochromium, 3-4% silicon carbide, 3-5% tungsten carbide, 2-4% electrolytic manganese, 10-19% ferroniobium, 4-6% ferrovanadium, 15-20% ferromolybdenum, and the remainder is Fe powder.

[0027] Furthermore, the mass fraction of chromium in the high-carbon ferrochrome is 68%, and the mass fraction of carbon is 8%; the mass fraction of silicon in the silicon carbide is 70%, and the mass fraction of carbon is 30%; the mass fraction of tungsten in the tungsten carbide is 94%, and the mass fraction of carbon is 6%; the mass fraction of niobium in the ferroniobium is 65%; the mass fraction of vanadium in the ferrovanadium is 50%; the mass fraction of molybdenum in the ferromolybdenum is 60%; the mass fraction of manganese in the electrolytic manganese is greater than 90%; and the mass fraction of carbon in the graphite is greater than 99.5%.

[0028] Furthermore, the particle size of the high carbon ferrochrome is 30-50 mesh; the particle sizes of the tungsten carbide, ferroniobium, ferromolybdenum and ferrovanadium are all 80-100 mesh; the particle size of the electrolytic manganese is 60-80 mesh; the particle size of the silicon carbide is 70-90 mesh; the particle size of the graphite is 40-60 mesh; and the particle size of the Fe powder is 100-150 mesh.

[0029] 2. The present invention provides a high-temperature, wear-resistant, flux-cored welding wire with a composite carbide-reinforced single-tooth roller surface. The raw materials for the flux-cored welding wire include the aforementioned flux core. The flux core fill factor in the flux-cored welding wire (i.e., the percentage of the area occupied by the flux core to the total cross-sectional area of ​​the wire) is 40-60%, preferably 40-50%, and more preferably 45-50%. The manufacturing process comprises: encasing the flux core described in the aforementioned embodiment with a metal shell.

[0030] The specific preparation process is:

[0031] (1) Powder selection and drying: Select alloy powder according to the 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.

[0032] (2) Powder screening: In order to ensure the consistency of the particle size of the same powder, each powder needs to be screened through a sieve according to the mesh size disclosed above.

[0033] (3) Powder preparation and mixing: Powder preparation is carried out based on the kilograms of each flux-cored welding wire, the filling rate, and the mass percentage of each powder. After powder preparation, the different powders need to be evenly mixed to ensure uniformity of the components in the flux-cored welding wire.

[0034] (4) Belt selection: Select stainless steel belt as the metal shell. The thickness of the steel belt is 0.3mm and the width is 12mm.

[0035] (5) Drawing: The steel strip passes through the forming rollers and changes from a flat surface to a U-shape. At this time, the pre-prepared core powder is fed into the U-shaped steel strip through a conveyor belt. After the U-shaped steel strip carrying the powder passes through the closing rollers continuously, the steel strip changes from a U-shape to an O-shape, and the steel strip closes, tightly wrapping the core powder.

[0036] (6) Reduction and packaging: The drawn flux-cored wire is passed through a drawing die of a certain diameter to achieve the required diameter of the finished product. The reduced flux-cored wire is loaded into an I-shaped wheel and sealed for storage before use.

[0037] 3. A welding method using a composite carbide reinforced single-tooth roller surface high-temperature wear-resistant flux-cored welding wire, wherein welding is performed using the composite carbide reinforced single-tooth roller surface high-temperature wear-resistant flux-cored welding wire prepared by the preparation method, and the welding process is an arc surfacing process.

[0038] The arc surfacing process parameters are: voltage: 25-30V, current: 380-480A, wire feeding speed: 1000mm / min, and length of the welding wire extending from the conductive nozzle: 15-25mm.

[0039] Furthermore, after welding is completed, the mass percentage of alloying elements in the obtained surfacing alloy is within the following ranges: C: 3-6%; Cr: 15-30%; Si: 0.5-2%; W: 1-3%; Mn: 0.5-3%; Nb: 2-8%; V: 1.0-3.0%; Mo: 4-6%; Fe and unavoidable impurities: balance.

[0040] In the present invention, the various elements function as follows:

[0041] C: Carbon is a crucial element in wear-resistant iron-based alloys. Small amounts of carbon can dissolve in the iron matrix, causing lattice distortion and thereby increasing the alloy's strength and hardness. When the carbon content is high enough, carbon reacts with elements like chromium and iron to form large quantities of carbides. These hard carbides significantly enhance the alloy's wear resistance and strength. Carbides can also pin dislocations at high temperatures, enhancing the alloy's high-temperature strength.

[0042] Cr: Cr combines with C to form high-hardness carbides, among which Cr7C3 has extremely high hardness, which can significantly improve the alloy's resistance to abrasive wear. At high Cr content, carbides are distributed in isolated blocks or chrysanthemum shapes, reducing the splitting effect on the matrix and improving the toughness of the alloy. In addition, Cr dissolves in the ferrite or martensite matrix, which can increase the hardness and strength of the matrix. When the Cr content is ≥12%, a dense Cr2O3 passivation film can be formed on the alloy surface to resist corrosion by corrosive media (such as acid and salt water). The Cr2O3 film can remain stable at high temperatures (<900°C), slowing down the oxidation and thermal fatigue of the alloy.

[0043] Nb: Niobium is a strong carbide-forming element that significantly improves the alloy's wear resistance by refining the microstructure, forming high-hardness carbides, and improving high-temperature stability. It performs particularly well under high-temperature, high-stress wear conditions. Nb and C form high-hardness, highly stable NbC carbides, which are much harder than Fe3C and Cr7C3, significantly improving the alloy's resistance to abrasive wear. NbC precipitates at the nanoscale in the matrix, hindering dislocation movement and enhancing matrix strength. It also promotes the growth of Cr7C3 phase and austenite grains, making the microstructure finer and more uniform, and improving impact toughness. NbC remains stable above 1000°C and is more resistant to high-temperature wear than the Cr7C3 phase. Furthermore, Nb can immobilize C, reducing the precipitation of Cr carbides, preventing intergranular corrosion, and improving the alloy's corrosion resistance.

[0044] W: Tungsten is a high-melting-point, strong carbide-forming element. In wear-resistant iron-based alloys, it significantly improves alloy performance by forming superhard carbides, increasing red hardness, and enhancing high-temperature wear resistance. WC's hardness is also much higher than that of Fe3C and Cr7C3, significantly enhancing the alloy's resistance to abrasive wear. Furthermore, W forms carbides such as (W,Cr)7C3 and (W,V)C with Cr, V, and Mo, enhancing carbide stability. W carbides can pin grain boundaries, refine the alloy structure, and improve the material's impact toughness.

[0045] Mo: Molybdenum forms Mo2C with carbon, which has a hardness between Cr7C3 and Fe3C, enhancing resistance to abrasive wear. Mo forms (Mo,Cr)7C3 and (Mo,V)C with Cr, V, and other materials, improving the thermal stability of carbides. Mo dissolves in the matrix, slowing high-temperature softening and enabling the alloy to maintain high strength at temperatures between 600 and 800°C. Furthermore, molybdenum promotes the formation of a dense oxide film at high temperatures, reducing surface degradation caused by high-temperature oxidation. NbC and Mo2C work synergistically to enhance the alloy's high-temperature wear resistance.

[0046] V: V is also a strong carbide-forming element, forming carbides that improve the alloy's wear resistance. These carbides, primarily precipitating at the nanoscale, can pin dislocations and grain boundaries, strengthening the matrix. V's solid solution in austenite increases the tendency for supercooled austenite to transform into martensite, promoting martensite formation. V's carbide, VC, can pin dislocations and grain boundaries at high temperatures, enhancing the alloy's high-temperature strength and impact toughness.

[0047] Mn, Si: Use manganese and silicon to jointly deoxidize and increase the element transition coefficient.

[0048] Fe: Fill the margin.

[0049] In order to better understand the present invention, the present invention will be further described below in conjunction with specific embodiments, but the content of the present invention is not limited to the following embodiments. The same parts in each embodiment are as follows:

[0050] In the following examples, all the raw materials used can be obtained from commercial sources.

[0051] In the following embodiments, the outer sheath of the flux-cored welding wire is made of stainless steel strip with a thickness of 0.3 mm and a width of 12 mm. The core composition of the flux-cored welding wire is specifically described in the embodiments. The steel strip is rolled into a U-shape after passing through rollers. The various powders in the formula are weighed in advance according to the designed ratio, dried, and mixed evenly before being mechanically added to the steel strip. The U-shaped steel strip is closed 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 welding wire with a diameter of 2.8 mm. A high-temperature, wear-resistant flux-cored welding wire with a single-tooth roller surface is obtained.

[0052] In the flux core, the particle size of the high carbon ferrochrome is 30-50 mesh; the particle sizes of the tungsten carbide, ferroniobium, ferromolybdenum and ferrovanadium are all 80-100 mesh; the particle size of the manganese is 60-80 mesh; the particle size of the silicon carbide is 70-90 mesh; the particle size of the graphite is 40-60 mesh; and the particle size of the Fe powder is 100-150 mesh.

[0053] The mass fraction of chromium in the high-carbon ferrochrome is 68%, and the mass fraction of carbon is 8%; the mass fraction of silicon in the silicon carbide is 70%, and the mass fraction of carbon is 30%; the mass fraction of tungsten in the tungsten carbide powder is 94%, and the mass fraction of carbon is 6%; the mass fraction of niobium in the ferroniobium is 65%; the mass fraction of vanadium in the ferrovanadium powder is 50%; the mass fraction of molybdenum in the ferromolybdenum is 60%; the mass fraction of manganese in the electrolytic manganese is greater than 90%; and the mass fraction of carbon in the graphite is greater than 99.5%.

[0054] During the welding process, arc surfacing process is used to prepare the surfacing alloy, and the welding process parameters are: voltage: 25-30V, current: 380-480A, wire feeding speed: 1000mm / min, and the length of the welding wire extending from the conductive nozzle: 15-25mm.

[0055] Hardness tests, abrasive wear tests, and friction wear tests were performed on the surfacing alloys prepared in the following examples. At the same time, to simulate the actual high-temperature working conditions of a single-toothed roller, the surfacing alloys were heat treated at 900°C for 2 hours and then cooled with the furnace. The heat-treated surfacing alloys were then subjected to hardness tests, abrasive wear tests, and friction wear tests. The specific test steps are as follows:

[0056] (1) The Rockwell hardness of the cladding alloy was tested using an HR-150A electric Brinell hardness tester. The 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 cladding alloy was the average of the data from the 10 test points.

[0057] (2) Abrasive wear tests were conducted using an MLS-225 wet sand rubber wheel abrasive wear tester. The wear specimen size was 57 mm × 25 mm × 10 mm. The main test parameters included: rubber wheel diameter of 176 mm, rubber wheel speed of 240 rpm, rubber wheel hardness of 60 Shore hardness, quartz sand of 40-70 mesh selected as abrasive, loading load of 100 N, 1000 g of water and 1500 g of quartz sand added during the test. Before each test, a pre-grinding at 2000 rpm was performed to prevent the surface roughness of the specimen from affecting the wear results. After pre-grinding, the specimen was weighed as the weight before wear; the specimen was immersed in an ethanol solution at 8000 rpm, ultrasonically cleaned, and then dried with a hair dryer. The specimen was weighed using a Beijing Sartorius precision balance with an accuracy of 0.0001 g. Three tests were conducted on each specimen, and the average value of the specimen loss weight was taken as the reference standard for wear resistance.

[0058] (3) High-temperature friction and wear tests were conducted using an MS-HT1000 high-temperature friction and wear testing machine. The wear specimen size was 20 mm × 20 mm × 7 mm. The test parameters were: φ4 silicon carbide, load 2000 g, friction radius 6 mm, rotation speed 300 r / min, test temperature at room temperature and 600 °C, and time 60 min. To reduce experimental error, three tests were conducted on each specimen. After the test, the OLMPUS-4100 laser confocal scanning microscope was used to obtain the three-dimensional morphology of the specimen wear scar and calculate the wear volume of the specimen. The wear scar morphology was observed using a field emission scanning electron microscope.

[0059] Example 1

[0060] The flux core is weighed according to the following percentages: graphite 7%, high carbon ferrochrome 25%, silicon carbide 4%, tungsten carbide 3.0%, electrolytic manganese 3.0%, ferroniobium 10%, ferrovanadium 4%, ferromolybdenum 15.0%, and the rest is Fe powder.

[0061] A surfacing alloy is prepared according to the surfacing process disclosed above in the present invention. The mass percentage of alloying elements in the obtained surfacing alloy is C: 4%; Cr: 17%; Si: 1.2%; W: 1%; Mn: 0.8%; Nb: 2.8%; V: 1.3%; Mo: 4.0%; and Fe as the balance.

[0062] The Rockwell hardness of the surfacing alloy is 52HRC, and in the abrasive wear test, the wear loss weight is 1.7710g; the Rockwell hardness after heat treatment is 45HRC, and the wear loss weight is 2.8266g; the friction depths at room temperature and 600℃ are 9μm and 16.4μm, respectively.

[0063] Example 2

[0064] The flux core is weighed according to the following percentages: graphite 8%, high carbon ferrochrome 25%, silicon carbide 3%, tungsten carbide 4.5%, electrolytic manganese 3.0%, ferroniobium 10%, ferrovanadium 5%, ferromolybdenum 18%, and the rest is Fe powder.

[0065] According to the surfacing process disclosed above, a surfacing alloy is prepared. The mass percentage of alloying elements in the obtained surfacing alloy is C: 4.9%; Cr: 18%; Si: 1.2%; W: 2%; Mn: 1.0%; Nb: 3.0%; V: 1.3%; Mo: 5.0%; and Fe as the balance.

[0066] The Rockwell hardness of the surfacing alloy is 55.5HRC, and the wear loss weight in the abrasive wear test is 1.0181g; the Rockwell hardness after heat treatment is 50HRC, and the wear weight loss is 1.7411g; in the friction and wear test, the wear depths at room temperature and 600℃ are 7.1μm and 13.2μm, respectively.

[0067] Example 3

[0068] The flux core is weighed according to the following percentages: graphite 8%, high carbon ferrochrome 28%, silicon carbide 3%, tungsten carbide 4.5%, electrolytic manganese 3.0%, ferroniobium 11.5%, ferrovanadium 5%, ferromolybdenum 18%, and the rest is Fe powder.

[0069] According to the surfacing process disclosed above, a surfacing alloy is prepared. The mass percentage of alloying elements in the obtained surfacing alloy is C: 5%; Cr: 20%; Si: 1.2%; W: 2.2%; Mn: 1.1%; Nb: 3.5%; V: 1.3%; Mo: 5.0%; and Fe as the balance.

[0070] The Rockwell hardness of the surfacing alloy is 62HRC, and the wear loss weight in the abrasive wear test is 0.7431g; the Rockwell hardness after heat treatment is 58HRC, and the wear weight loss is 1.0291g; in the friction and wear test, the wear depths at room temperature and 600℃ are 5.7μm and 11.2μm, respectively.

[0071] Example 4

[0072] The flux core is weighed according to the following percentages: graphite 8%, high carbon ferrochrome 37%, silicon carbide 3%, tungsten carbide 4.5%, electrolytic manganese 3.0%, ferroniobium 18%, ferrovanadium 5%, ferromolybdenum 18%, and the rest is Fe powder.

[0073] According to the surfacing process disclosed above, a surfacing alloy is prepared. The mass percentage of alloying elements in the obtained surfacing alloy is C: 5.3%; Cr: 21%; Si: 1.2%; W: 2.2%; Mn: 1.1%; Nb: 5.4%; V: 1.3%; Mo: 5.0%; and Fe as the balance.

[0074] The surfacing process produces less spatter, and the surface of the surfacing alloy is bright, flat, and has tiny cracks. The Rockwell hardness of the surfacing alloy is 65HRC, and in the abrasive wear test, the wear loss weight is 0.5917g. After heat treatment, the Rockwell hardness is 61HRC, and the wear weight loss is 0.6273g. In the friction and wear test, the wear depths at room temperature and 600°C are 4.5μm and 9μm, respectively.

[0075] Example 5

[0076] The flux core is weighed according to the following percentages: graphite 8%, high carbon ferrochrome 46%, silicon carbide 3%, tungsten carbide 5%, electrolytic manganese 3.0%, ferroniobium 18%, ferrovanadium 5%, ferromolybdenum 18%, and the rest is Fe powder.

[0077] According to the surfacing process disclosed above, a surfacing alloy is prepared. The mass percentage of alloying elements in the obtained surfacing alloy is C: 5.5%; Cr: 24%; Si: 1.2%; W: 2.5%; Mn: 1%; Nb: 5.4%; V: 1.3%; Mo: 5.0%; and Fe as the balance.

[0078] The amount of spatter in the surfacing process is small, the weld is beautiful, the surface of the surfacing alloy is bright, without obvious pores, high flatness and no cracks (such as Figure 1 The Rockwell hardness of the surfacing alloy is 67.5HRC, and the wear loss in the abrasive wear test is 0.3242g; the Rockwell hardness after heat treatment is 62.2HRC, and the wear loss is 0.3613g; in the friction and wear test, the wear depths at room temperature and 600℃ are 4.1μm and 8.2μm respectively (as shown in Figure 2). Figure 2 shown).

[0079] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A drug core, characterized in that: In terms of mass percentage, it includes the following components: Graphite 5-10%, high carbon ferrochrome 20-50%, silicon carbide 2-5%, tungsten carbide 2-6%, electrolytic manganese 1-4%, ferroniobium 10-20%, ferrovanadium 3-7%, ferromolybdenum 15-25%, and the rest is Fe powder.

2. The drug core according to claim 1, characterized in that: Calculated by mass percentage, the invention comprises the following components: 6-9% graphite, 25-46% high carbon ferrochrome, 3-4% silicon carbide, 3-5% tungsten carbide, 2-4% electrolytic manganese, 10-19% ferroniobium, 4-6% ferrovanadium, 15-20% ferromolybdenum, and the rest is Fe powder.

3. A drug core according to claim 1 or 2, characterized in that: The mass fraction of chromium in the high-carbon ferrochrome is 68%, and the mass fraction of carbon is 8%; the mass fraction of silicon in the silicon carbide is 70%, and the mass fraction of carbon is 30%; the mass fraction of tungsten in the tungsten carbide is 94%, and the mass fraction of carbon is 6%; the mass fraction of niobium in the ferroniobium is 65%; the mass fraction of vanadium in the ferrovanadium is 50%; the mass fraction of molybdenum in the ferromolybdenum is 60%; the mass fraction of manganese in the electrolytic manganese is greater than 90%; and the mass fraction of carbon in the graphite is greater than 99.5%.

4. A drug core according to claim 1 or 2, characterized in that: The particle size of the high carbon ferrochrome is 30-50 mesh; the particle sizes of the tungsten carbide, ferroniobium, ferromolybdenum and ferrovanadium are all 80-100 mesh; the particle size of the electrolytic manganese is 60-80 mesh; the particle size of the silicon carbide is 70-90 mesh; the particle size of the graphite is 40-60 mesh; and the particle size of the Fe powder is 100-150 mesh.

5. A high-temperature wear-resistant flux-cored welding wire with a composite carbide-reinforced single-tooth roller surface, characterized by: The raw material of the flux-cored welding wire includes the flux core according to any one of claims 1 to 4.

6. The high-temperature wear-resistant flux-cored welding wire with a composite carbide reinforced single tooth roller surface according to claim 5, characterized in that: The filling rate of the flux core in the flux cored welding wire is 40-60%.

7. A method for preparing the high-temperature wear-resistant flux-cored welding wire with a composite carbide reinforced single tooth roller surface according to claim 5 or 6, characterized in that: The drug core is wrapped with a metal shell.

8. A welding method using a high-temperature wear-resistant flux-cored wire reinforced with a composite carbide on the surface of a single tooth roller, characterized in that: The high-temperature wear-resistant flux-cored welding wire on the surface of the composite carbide-reinforced single-tooth roller prepared by the preparation method according to claim 7 is used for welding, and the welding process is an arc surfacing process.

9. The welding method according to claim 8, wherein: The arc surfacing process parameters are: voltage: 25-30V, current: 380-480A, wire feeding speed: 1000mm / min, length of welding wire extending from the conductive nozzle: 15-25mm.

10. The welding method according to claim 8 or 9, characterized in that: After welding is completed, the mass percentage of alloy elements in the obtained cladding alloy is within the following ranges: C: 3-6%; Cr: 15-30%; Si: 0.5-2%; W: 1-3%; Mn: 0.5-3%; Nb: 2-8%; V: 1.0-3.0%; Mo: 4-6%; Fe and inevitable impurities: balance.

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