Preparation method of reinforced high-entropy alloy laser cladding coating based on carbide and rare earth oxide

Abstract

The invention discloses a preparation method of an enhanced high-entropy alloy laser cladding coating based on carbide and rare earth oxide. The preparation method is specifically implemented according to the following steps: step 1, designing a laser cladding scheme; step 2, determining laser process parameters; step 3, preparing a cladding layer; and 4, testing the performance of the cladding layer. The mechanical property and the tribological property of the cladding layer are improved, the service life of the gear is prolonged, and the reliability and the safety of equipment are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of gear repair, and in particular relates to a method for preparing a laser cladding coating based on carbide and rare earth oxide reinforced high entropy alloy. Background Art

[0002] The rocker arm of a coal mining machine is a core component of coal mining machinery. The rocker arm gear transmission system is characterized by heavy loads and difficult lubrication. Its reliability has a significant impact on the safety and economic benefits of underground coal mining. Due to complex and changing operating conditions and harsh environments, rocker arm failures are frequent in underground coal mining machines. Statistics on the failure rate of rocker arm gearboxes for imported coal mining machines in the Shendong mining area in recent years show that rocker arm gearboxes account for an average of 34.2% of the failure rate, with a trend of increasing year by year. Extensive research has shown that rocker arm gearbox failure modes include micropitting, rolling fatigue, and wear. Tooth surfaces are subject to excessive contact shear stress under alternating loads and excessive stress cycles, which can lead to damage such as bonding, spalling, and surface pitting. As core equipment components, transmission gears are expensive to manufacture and have long production cycles. Severe gear damage can result in significant economic losses.

[0003] Due to the complex and harsh operating environment of rocker gears, their gear transmission systems are prone to tooth breakage, seriously impacting the continuity and safety of underground operations. Traditional gear repair methods, such as welding and brazing, often fail to effectively address the strength, wear resistance, and friction performance issues associated with broken gear repair.

[0004] At present, the repair methods for worn gears mainly include surfacing, spraying, laser cladding, etc. As an advanced surface repair technology, laser cladding technology uses high-energy-density laser beam irradiation to rapidly heat the powder and substrate surface, causing the powder and substrate surface to melt and then rapidly solidify, thereby forming a high-performance laser cladding layer on the substrate surface, significantly improving the wear resistance and corrosion resistance of the part surface, and achieving the purpose of restoring size. The advantages of strong bonding between the cladding layer and the substrate and excellent cladding layer performance can effectively repair the wear problem of the gear tooth surface. However, the existing laser cladding process still faces some technical challenges when repairing gears, such as the optimization of the microstructure and properties of the cladding layer, the control of crack sensitivity, and the reasonable addition of high-entropy alloy reinforcement phases. Therefore, how to improve the comprehensive performance of high-entropy alloys by selecting laser cladding process parameters and adding reinforcement phases, and improve the mechanical properties and tribological properties of the cladding layer, has become a key technology for solving the problem of repairing rocker arm gears of underground coal mining machines. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for preparing a high-entropy alloy laser cladding coating based on carbides and rare earth oxides, thereby improving the mechanical and tribological properties of the cladding layer, increasing the service life of the gears, and enhancing the reliability and safety of the equipment.

[0006] The technical solution adopted by the present invention is a method for preparing a carbide and rare earth oxide reinforced high entropy alloy laser cladding coating, which is specifically implemented according to the following steps: Step 1: Laser cladding scheme design; Step 2: Determine laser process parameters; Step 3, preparing the cladding layer; Step 4: Testing the performance of the cladding layer.

[0007] The present invention is also characterized in that: Step 1 is implemented as follows: Step 1.1: Select steel plate as the substrate material, and the cladding powder is a high-entropy alloy powder FeCoNiCrMo with an equimolar mass ratio, with a ceramic hard phase TiC as the reinforcement phase to increase the hardness and wear resistance of the composite coating; rare earth oxide Y2O3 is added at a mass fraction of 1-3% to improve the ductility and toughness of the cladding layer and reduce defects; Step 1.2: Set the range of laser power P, scanning speed V, and powder feeding rate C, with the cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance as the research objectives; Step 1.3: Grind the substrate to remove the surface impact layer, use anhydrous ethanol as a solvent, and perform ultrasonic cleaning to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate. Step 1.4: Weigh the cladding powder in step 1 and mix it in a planetary ball mill. Use ceramic balls as the ball milling medium for ball milling. After the ball milling is completed, place it in a vacuum drying oven for heating to obtain a composite powder.

[0008] In step 1.1, the mass fraction of the high entropy alloy powder FeCoNiCrMo is 82%-94%; the mass fraction of the ceramic hard phase TiC is 5%-15%; and the mass fraction of the rare earth oxide Y2O3 is 1-3%.

[0009] In step 1.2, the laser power P = 1500 W -2100 W, the scanning speed V = 15 mm / s -21 mm / s, and the powder feeding rate C = 16 g / min -24 g / min.

[0010] The ultrasonic cleaning time in step 1.3 is 10 min ~15 min.

[0011] In step 1.4, the ball-to-material ratio is 3-5:1, the ball mill speed is 300 r / min-400 r / min, the ball milling time is 3 h-4 h, the vacuum heating temperature is 80-85°C, and the vacuum heating time is 6-8 h.

[0012] Step 2 is implemented as follows: Step 2.1, perform a single-pass cladding experiment on the pretreated substrate on the steel substrate according to the different laser process parameters selected in step 1.2, with the interval between each two passes being 5-10 mm; Step 2.2: Cut the single-coat coating specimen prepared in step 2.1 on a cross section perpendicular to the cladding direction. Mount the specimen using a metallographic mounting machine equipped with a hot mounting resin, grind and polish it, and ultrasonically clean it in anhydrous ethanol for 10 to 15 minutes. Perform a microhardness test on the polished cross section. Finally, etch the cross section with aqua regia for 15 to 20 seconds, rinse it with anhydrous ethanol, dry it in a vacuum desiccator, and observe the microstructure. Step 2.3. Establish a mapping relationship between laser process parameters and cladding layer quality. Comprehensively analyze the hardness, dilution rate, height, width of the cladding layer under different process parameters, as well as the cross-sectional microstructure after corrosion in step 2.2. Determine the reasonable range of laser power, scanning speed, and powder feeding rate as constraints through single-factor experiments to select process parameters.

[0013] The process parameters selected in step 2.3 are as follows: The height of the cladding layer is 0.3mm~0.8mm, the width of the cladding layer is 1mm~1.5mm, and the low dilution rate is 10%~25%.

[0014] Step 3 is implemented as follows: Step 3.1: Perform a laser cladding experiment using the laser process parameters of step 2.3 and the composite powder prepared in step 1.4. Select an overlap ratio of 40% to 60% to prepare a cladding layer. Select the number of cladding layers based on the coating thickness requirement of 0.1 to 10 mm. Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer into discs with a diameter of 20 mm to 30 mm, grind and polish them, etch the cross section with aqua regia for 15 s to 20 s, rinse with anhydrous ethanol, and dry in a vacuum dryer to obtain the prepared cladding layer.

[0015] The beneficial effect of the present invention is that, based on the preparation method of carbide and rare earth oxide reinforced high-entropy alloy laser cladding coating, by introducing high-hardness carbides and rare earth oxides as reinforcing phases, the microhardness of the cladding layer reaches 850-1050HV, which is approximately 30-40% higher than that of traditional high-entropy alloy coatings and more than twice that of the base material. The dispersed distribution of the reinforcing phase forms a "soft-hard" synergistic structure with the high-entropy alloy substrate, while maintaining high hardness while avoiding the brittle failure problem of traditional hard coatings. In terms of friction and wear performance, the coating exhibits excellent wear resistance, with a volume wear rate as low as 6.78×10 -6mm 3 / N·m, a decrease of over 50% compared to the substrate. The coating is particularly suitable for extremely high-wear conditions, such as wear-resistant liners in mining machinery, hydraulic plungers in construction machinery, and rollers in metallurgical equipment. It can significantly extend the service life of key components and significantly reduce equipment maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the laser cladding principle in the method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides of the present invention; Figure 2 This is a SEM schematic diagram of the composite powder after uniform mixing and drying in the method for preparing the carbide and rare earth oxide reinforced high entropy alloy laser cladding coating of the present invention; Figure 3 It is a schematic diagram of the cross section of a single coating in the method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides of the present invention; Figure 4 It is a schematic diagram of the microstructure morphology of the cladding layer in the method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides of the present invention; Figure 5 Schematic diagram of the surface hardness of the 82% FeNiCoCrMo+15% TiC+3% Y2O3 composite coating and the substrate material in the preparation method of the carbide and rare earth oxide reinforced high entropy alloy laser cladding coating of the present invention; Figure 6 This is a schematic diagram of the surface friction coefficient of the 82% FeNiCoCrMo+15% TiC+3% Y2O3 composite coating and the substrate material in the preparation method of the carbide and rare earth oxide reinforced high entropy alloy laser cladding coating of the present invention; Figure 7 The wear scar depth and width of the 82% FeNiCoCrMo+15% TiC+3% Y2O3 composite coating and the substrate surface after wear resistance testing in the preparation method of the carbide and rare earth oxide reinforced high entropy alloy laser cladding coating of the present invention; Figure 8 This is a graph showing the lubrication performance of a coating in a method for preparing a high-entropy alloy laser cladding coating based on carbides and rare earth oxides; Figure 9 This is a wear scar profile curve diagram in the method for preparing a high entropy alloy laser cladding coating reinforced with carbides and rare earth oxides according to the present invention; Figure 10 It is a schematic diagram of the volume wear rate in the method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides of the present invention. DETAILED DESCRIPTION

[0017] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] The present invention is based on a method for preparing a carbide and rare earth oxide reinforced high entropy alloy laser cladding coating, which is specifically implemented according to the following steps: Step 1: Laser cladding scheme design; Step 1 is implemented as follows: Step 1.1. Select steel plate as the substrate material, and the cladding powder is a high-entropy alloy powder FeCoNiCrMo with an equimolar mass ratio, with a mass fraction of 82%-94%. The ceramic hard phase TiC is used as the reinforcement phase, with a mass fraction of 5%-15% to increase the hardness and wear resistance of the composite coating. The rare earth oxide Y2O3 is added with a mass fraction of 1-3% to improve the ductility and toughness of the cladding layer and reduce defects. Step 1.2: Set the laser power P, scanning speed V, and powder feeding rate C ranges, with the cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance as research targets, where P = 1500-2100 W, V = 15-21 mm / s, and C = 16 g-24 g / min. Step 1.3: Use metallographic sandpaper to coarsely grind the substrate to remove the surface impact layer. Use anhydrous ethanol as solvent to ultrasonically clean the substrate in an ultrasonic cleaning machine for 10 to 15 minutes to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate. Step 1.4: Weigh the cladding powder in step 1 and mix it in a planetary ball mill. Use ceramic balls as the ball milling medium and control the ball-to-material ratio to 3-5:1. Then, ball mill at a speed of 300-400 r / min for 3-4 hours. After ball milling, place it in a vacuum drying oven, heat it to 80-85°C, and dry it for 6-8 hours to obtain a composite powder. Figure 2 Its SEM schematic diagram.

[0019] Step 2: Determine laser process parameters; Step 2 is implemented as follows: Step 2.1, place the pretreated substrate on the workbench of the laser cladding equipment and perform a single-pass cladding layer experiment on the steel substrate according to the different laser process parameters selected in step 1.2, with the interval between each two passes being 5-10 mm; Step 2.2: Cut the single-coat sample prepared in step 2.1 on a cross section perpendicular to the cladding direction. Mount the sample using a metallographic mounting machine equipped with a hot mounting resin. Grind it with #320-#2000 metallographic sandpaper, polish it using a polishing grinder, and ultrasonically clean it in anhydrous ethanol for 10-15 minutes. Perform a microhardness test on the polished section. Finally, etch the section with aqua regia for 15-20 seconds, rinse it with anhydrous ethanol, dry it in a vacuum desiccator, and observe the microstructure. Step 2.3: Establish a mapping relationship between laser process parameters and cladding layer quality, and conduct a comprehensive analysis of the hardness, dilution rate, height, width of the cladding layer under different process parameters, as well as the cross-sectional microstructure after etching in step 2.2; Figure 3 The cross-sectional diagram is shown. Single-factor experiments were conducted to determine the optimal process parameters by using the appropriate ranges of laser power, scanning speed, and powder feed rate as constraints. Excessively low power results in insufficient powder melting, resulting in unmelted particles in the cladding layer and poor bonding. Excessively high power overheats the molten pool, significantly increasing the substrate dilution rate, contaminating the coating with matrix elements, and reducing hardness. Excessively low scanning speeds result in excessive heat input, leading to an imbalanced aspect ratio of the cladding layer and the potential for collapse or porosity. Excessively high speeds reduce the cladding layer height, resulting in insufficient powder fusion and reduced density. Excessively low powder feed rates result in insufficient cladding layer thickness and low coverage. Excessively high powder feed rates result in incomplete powder accumulation, increased surface roughness, and uneven hardness. The optimal process parameters were selected to achieve a high microhardness (above 800 HV), a dense microstructure, an appropriate cladding layer height of 0.3 mm to 0.8 mm, a width of 1 mm to 1.5 mm, and a low dilution rate of 10% to 25%.

[0020] Step 3, preparing the cladding layer; Step 3 is implemented as follows: Step 3.1: Use the optimized laser process parameters of step 2.3 and the composite powder prepared in step 1.4 to conduct a laser cladding experiment. Select an overlap rate of 40%-60% to prepare the cladding layer. Select the number of cladding layers according to the coating thickness requirement of 0.1-10 mm. Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer into discs with a diameter of 20-30 mm, grind and polish them with sandpaper with a grit size of 320-2000, etch the cross section with aqua regia (HNO3:HCl=1:3~4) for 15-20 seconds, rinse with anhydrous ethanol, and dry in a vacuum dryer to obtain the prepared cladding layer, which has the advantages of high hardness, dense microstructure, strong wear resistance, and certain lubricity compared to the substrate.

[0021] Cladding layer performance test: Please follow the steps below to implement it: Scanning electron microscope (SEM) was used to observe the microstructure of the cladding layer. The cross-sectional hardness of the cladding layer was measured using a microhardness tester to analyze the mechanical properties of the cladding layer. The tribological performance of composite coatings with different cladding material combinations was tested. Friction coefficient, wear depth and other indicators were tested using a friction and wear tester. The tribological performance of the cladding layer when grinding against different materials was studied through dry friction experiments. The wear mechanism of the cladding layer is revealed based on the friction coefficient, wear scar profile and volume wear rate.

[0022] like Figure 1 As shown: A high-energy laser beam acts as a heat source, focused on the workpiece surface, rapidly heating and melting the base material and powder. Metal powder is fed into the molten pool synchronously with the laser beam through a coaxial nozzle, ensuring even distribution of the powder within the laser's active area. Once in the molten pool, the powder is melted by the laser beam and mixes with the molten metal on the base material surface, forming a metallurgical bond. After the laser beam is removed, the molten pool rapidly cools and solidifies, forming a dense cladding layer that is firmly bonded to the base material. This process is repeated, layer by layer, to create the desired cladding thickness.

[0023] Figure 4 The microstructure of the cladding layer is 82%FeNiCoCrMo+15%TiC+3%Y2O3 composite coating. Figure 4 The cladding layer is composed of dendrites with disordered arrangement, which can increase the resistance to dislocation movement, enhance the material's ability to resist plastic deformation, and improve the hardness of the cladding layer.

[0024] Figure 5 The following is a comparison chart of the surface hardness of 82%FeNiCoCrMo+15%TiC+3%Y2O3 composite coating and substrate material. Figure 5 (Comparison of the curves in the figure) The hardness of the 45 steel substrate is in the range of 200-300HV, while the hardness of the cladding layer is around 1000HV, which is about 4 times that of the substrate, a significant improvement.

[0025] Example 1 A laser cladding repair process for rocker gears of underground coal mining machines is based on carbides and rare earth oxides to enhance the performance of high-entropy alloys. The following is the laser cladding scheme design and cladding layer preparation process.

[0026] Step 1: Laser Cladding Solution Step 1 is as follows: Step 1.1 Select 45 steel plate as the substrate material with a thickness of 10 mm. The cladding powder is a FeNiCoCrMo high-entropy alloy powder with an approximately equimolar mass ratio. The ceramic hard phase TiC is used as the reinforcement phase to increase the hardness and wear resistance of the composite coating. The rare earth oxide Y2O3 is added to improve the ductility and toughness of the cladding layer and reduce defects.

[0027] Step 1.2: Select appropriate laser power P, scanning speed V, and powder feed rate C. The cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance are the research objectives. For example, P = 1800W, V = 18mm / s, and C = 20g / min.

[0028] Step 1.3: Use grit #320 metallographic sandpaper to coarsely grind the substrate to remove the surface impact layer. Use anhydrous ethanol as solvent to clean it in an ultrasonic cleaner for 15 minutes to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate.

[0029] Step 1.4: Mix 82% FeNiCoCrMo high-entropy alloy powder, 15% ceramic carbide TiC powder, and 3% rare earth oxide Y2O3 in a planetary ball mill using ceramic balls as the milling media, maintaining a ball-to-powder ratio of 3:1. Mill the mixture at 300 rpm for 4 hours. After milling, heat the mixture to 85°C in a vacuum drying oven and dry it for 6 hours to obtain a composite powder.

[0030] Step 2: Determine laser process parameters Step 2 is as follows: Step 2.1: Place the pretreated substrate 45 steel on the workbench of the laser cladding equipment and perform a single-pass cladding layer experiment on the steel substrate according to the laser process parameters.

[0031] Step 2.2: Cut the single-coat coating specimen prepared in Step 2.1 in a cross-section perpendicular to the cladding direction. Mount the specimen using a metallographic mounting machine equipped with a hot-mounting resin. Grind with #320 to #2000 metallographic sandpaper, polish with a polishing grinder, and ultrasonically clean in anhydrous ethanol for 15 minutes. Microhardness testing was performed on the polished cross-section, and the average hardness of the cladding cross-section was 991 Hv. Finally, the cross-section was etched with aqua regia for 15 seconds, rinsed with anhydrous ethanol, and dried in a vacuum desiccator. Microstructural observation was performed.

[0032] Step 3: Preparation of cladding layer Step 3 is as follows Step 3.1: Perform laser cladding using the same laser process parameters as in step 2 and the composite powder (82% FeNiCoCrMo, 15% TiC, 3% Y2O3) prepared in step 1.4. A cladding layer with an overlap ratio of 40% was prepared. The coating thickness was 0.5 mm, and the number of cladding layers was one.

[0033] Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer sample into a disc with a diameter of 30 mm, grind it with sandpaper with a grit size of 320-2000, and polish and etch it.

[0034] Step 4: Test the performance of the cladding layer, as follows Step 4.1: Study the wear resistance of the composite coating on a Tribo-lab standard friction tester. The relative motion between the ball and the disc is rotational.

[0035] The lower specimen consisted of an 82% FeNiCoCrMo + 15% TiC + 3% Y2O3 composite coating on a 45 steel substrate, while the upper specimen was a 9.5 mm φ Si3N4 ceramic ball. Dry friction was used for lubrication, and all tests were conducted at a temperature of 25.0°C and a relative humidity of 40%–45%. Before the experiments began, the specimen and fixture were ultrasonically cleaned in anhydrous ethanol for 10 minutes and then dried with a hair dryer. Experimental parameters included a load of 10 N, a motor speed of 1000 rpm, a friction circle radius of 7.5 mm, and a test duration of 30 minutes per set.

[0036] Figure 6 The friction coefficient between the 82% FeNiCoCrMo+15% TiC+3% Y2O3 composite coating and the 45 steel substrate is shown in Figure 2. It can be seen that the friction coefficient of the 45 steel substrate fluctuates around 0.8 after 300 seconds, while the friction coefficient of the composite coating stabilizes at 0.49 after 100 seconds.

[0037] The composite coating has the effect of significantly reducing the friction coefficient compared to the substrate surface.

[0038] Figure 7 The wear scar profiles of the 82% FeNiCoCrMo+15% TiC+3% Y2O3 composite coating and the 45 steel substrate are shown in Figure 2. It can be seen that the wear scar width and width of the composite coating are smaller than those of the substrate, which significantly improves the wear resistance.

[0039] Example 2 A laser cladding repair process for rocker gears of underground coal mining machines is based on carbides and rare earth oxides to enhance the performance of high-entropy alloys. The following is the laser cladding scheme design and cladding layer preparation process.

[0040] Step 1: Laser Cladding Solution Step 1 is as follows: Step 1.1: Select 45 steel plate as the substrate material with a thickness of 10 mm. The cladding powder is FeNiCoCrMo high-entropy alloy powder with an approximately equimolar mass ratio. The ceramic hard phase TiC is used as the reinforcement phase to increase the hardness and wear resistance of the composite coating. The rare earth oxide Y2O3 is added to improve the ductility and toughness of the cladding layer and reduce defects.

[0041] Step 1.2: Select a reasonable range of laser power P, scanning speed V, and powder feed rate C, with the cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance as the research objectives. P = 1500W, 1800W, 2100W; V = 15 mm / s, 18 mm / s, 21 mm / s; C = 16 g / min, 20 g / min, 24 g / min.

[0042] Step 1.3: Use grit #320 metallographic sandpaper to coarsely grind the substrate to remove the surface impact layer. Use anhydrous ethanol as solvent to clean it in an ultrasonic cleaner for 15 minutes to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate.

[0043] Step 1.4: Mix 82% (by mass) of high-entropy alloy FeNiCoCrMo powder, 18% (by mass) of ceramic carbide TiC powder, and 3% (by mass) of rare earth oxide Y2O3 in a planetary ball mill. Use ceramic balls as the milling medium, maintaining a ball-to-powder ratio of 3:1. Mill the mixture at 300 rpm for 4 hours. After milling, heat the mixture to 85°C in a vacuum drying oven and dry it for 6 hours to obtain a composite powder.

[0044] Step 2: Determine laser process parameters Step 2 is as follows: Step 2.1: Place the pretreated 45 steel substrate on the workbench of the laser cladding equipment and perform a single-pass cladding layer experiment on the steel substrate according to the laser process parameters, with a spacing of 5 mm between each two passes.

[0045] Step 2.2: Cut the single-coat specimen prepared in Step 2.1 in a cross-section perpendicular to the cladding direction. Mount the specimen using a metallographic mounting machine equipped with a hot-mounting resin. Grind with #320 to #2000 metallographic sandpaper, polish with a polishing grinder, and ultrasonically clean in anhydrous ethanol for 15 minutes. Perform a microhardness test on the polished section. Finally, etch the section with aqua regia for 15 seconds, rinse with anhydrous ethanol, dry in a vacuum desiccator, and observe the microstructure.

[0046] Step 2.3. Establish a mapping relationship between laser process parameters and cladding layer quality. Comprehensively analyze the hardness, dilution rate, height, width of the cladding layer under different process parameters, as well as the cross-sectional microstructure after corrosion in step 2.2. Through single-factor experiments, determine the reasonable range of laser power, scanning speed, and powder feeding rate as constraints, and select the optimal process parameters.

[0047] Step 3: Preparation of cladding layer Step 3 is as follows Step 3.1: Use the optimized laser process parameters of step 2.3 and the 82% FeNiCoCrMo+15% TiC+3% Y2O3 composite powder prepared in step 1.4 to carry out laser cladding experiments, and select an overlap rate of 60% to prepare the cladding layer.

[0048] Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer sample into a disc with a diameter of 30 mm, grind it with sandpaper with a grit size of #320-#2000, and polish it.

[0049] Step 4: Cladding layer performance test Step 4 is as follows Step 4.1: Use a microhardness tester to measure the cross-sectional hardness of the cladding layer and analyze its mechanical properties. The average cross-sectional hardness of the cladding layer is 1028.46 HV, which is approximately 3.88 times higher than that of the substrate.

[0050] Step 4.2: The composite coating was tribologically tested. Friction coefficient, wear depth, and other indicators were measured using a friction and wear tester. Dry friction experiments were conducted to investigate the tribological properties of the cladding layer when worn against different materials. The average friction coefficient of the coating was 0.46, significantly lower than the substrate's 0.79. This indicates that the coating exhibits excellent lubricity.

[0051] Step 4.3: Based on the friction coefficient, wear scar profile, and volume wear rate, the wear mechanism of the cladding layer was revealed. The test revealed that the wear scar width and depth of the 45 steel substrate were approximately 1.78 mm and 7.68 μm, respectively, and the volume wear rate was 22.29×10 -6 mm 3 / N·m; the wear scar width and depth of the coating are approximately 0.92 mm and 5.13 μm, respectively, and the volume wear rate is 6.78×10 -6 mm 3 / N·m, which is about 69.58% lower than that of the matrix.

[0052] Example 3 A laser cladding repair process for rocker gears of underground coal mining machines based on the properties of high-entropy alloys enhanced by carbides and rare earth oxides. The following is the laser cladding scheme design and cladding layer preparation process.

[0053] Step 1: Laser Cladding Solution Step 1 is as follows: Step 1.1 Select 45 steel plate as the substrate material with a thickness of 10 mm. The cladding powder is a FeNiCoCrMo high-entropy alloy powder with an approximately equimolar mass ratio. The ceramic hard phase TiC is used as the reinforcement phase to increase the hardness and wear resistance of the composite coating. The rare earth oxide Y2O3 is added to improve the ductility and toughness of the cladding layer and reduce defects.

[0054] Step 1.2: Select appropriate laser power P, scanning speed V, and powder feed rate C. The cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance are the research objectives. For example, P = 1800W, V = 18mm / s, and C = 20g / min.

[0055] Step 1.3: Use grit #320 metallographic sandpaper to coarsely grind the substrate to remove the surface impact layer. Use anhydrous ethanol as solvent to clean it in an ultrasonic cleaner for 15 minutes to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate.

[0056] In step 1.4, 92% FeNiCoCrMo + 5% TiC + 3% Y2O3, 87% FeNiCoCrMo + 10% TiC + 3% Y2O3, and 82% FeNiCoCrMo + 15% TiC + 3% Y2O3 were mixed in a planetary ball mill using ceramic balls at a ball-to-material ratio of 3:1. The mixture was then ball-milled at 300 r / min for 4 h. After milling, the mixture was dried in a vacuum drying oven at 85°C for 6 h to obtain a composite powder.

[0057] Step 2: Determine laser process parameters Step 2 is as follows: Step 2.1: Place the pretreated substrate 45 steel on the workbench of the laser cladding equipment and perform a single-pass cladding layer experiment on the steel substrate according to the laser process parameters.

[0058] Step 2.2: Cut the single-coat specimen prepared in Step 2.1 in a cross-section perpendicular to the cladding direction. Mount the specimen using a metallographic mounting machine equipped with a hot-mounting resin. Grind with #320 to #2000 metallographic sandpaper, polish with a polishing grinder, and ultrasonically clean in anhydrous ethanol for 15 minutes. Perform a microhardness test on the polished section. Finally, etch the section with aqua regia for 15 seconds, rinse with anhydrous ethanol, dry in a vacuum desiccator, and observe the microstructure.

[0059] Step 2.3. Establish a mapping relationship between laser process parameters and cladding layer quality. Comprehensively analyze the hardness, dilution rate, height, width of the cladding layer under different process parameters, as well as the cross-sectional microstructure after corrosion in step 2.2. Through single-factor experiments, determine the reasonable range of laser power, scanning speed, and powder feeding rate as constraints, and select the optimal process parameters.

[0060] Step 3: Preparation of cladding layer Step 3 is as follows Step 3.1: Use the optimized laser process parameters of step 2.3 and the three composite powders prepared in step 1.4 to carry out laser cladding experiments, and select an overlap rate of 60% to prepare the cladding layer.

[0061] Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer sample into a disc with a diameter of 30 mm, grind it with sandpaper with a grit size of #320-#2000, and polish and etch it.

[0062] Step 4: Test the performance of the cladding layer, as follows Step 4.1: Use a microhardness tester to measure the cross-sectional hardness of the cladding layer and analyze the mechanical properties of the cladding layer.

[0063] Step 4.2: Use a microhardness tester to measure the cross-sectional hardness of the cladding layer and analyze its mechanical properties. The average hardness of the cladding layer with 5% TiC is 876.94 HV, 10% TiC is 943.45 HV, and 15% TiC is 1028.46 HV. The TiC content significantly improves the coating hardness.

[0064] Step 4.3: Test the tribological properties of the composite coating. A friction and wear tester was used to measure the friction coefficient, wear depth, and other indicators. Dry friction experiments were conducted to investigate the tribological properties of the cladding layer when worn against different materials. The average friction coefficients of the cladding layers containing 5%, 10%, and 15% TiC were 0.55, 0.51, and 0.46, respectively. This indicates that increasing the TiC content can reduce the friction coefficient and improve the coating's lubricity.

[0065] Step 4.4: Based on the friction coefficient, wear scar profile, and volume wear rate, reveal the wear mechanism of the cladding layer. The wear scar width and depth of the 5% TiC cladding layer are approximately 1.31 mm and 7.26 μm, respectively, and the volume wear rate is 11.35×10 -6 mm 3 / N·m. The wear scar width and depth of the 10% TiC cladding layer are approximately 1.18 mm and 6.35 μm, respectively, and the volume wear rate is 8.49×10 -6 mm 3 / N·m. The wear scar width and depth of the 15% TiC cladding layer are approximately 0.92 mm and 5.13 μm, respectively, and the volume wear rate is 6.78×10 -6 mm 3 / N·m. The higher the TiC content, the smaller the volume wear rate and the stronger the wear resistance of the coating.

[0066] Example 4 A laser cladding repair process for rocker gears of underground coal mining machines based on the properties of high-entropy alloys enhanced by carbides and rare earth oxides. The following is the laser cladding scheme design and cladding layer preparation process.

[0067] Step 1: Laser Cladding Solution Step 1 is as follows: Step 1.1 Select 45 steel plate as the substrate material with a thickness of 10 mm. The cladding powder is a FeNiCoCrMo high-entropy alloy powder with an approximately equimolar mass ratio. The ceramic hard phase TiC is used as the reinforcement phase to increase the hardness and wear resistance of the composite coating. The rare earth oxide Y2O3 is added to improve the ductility and toughness of the cladding layer and reduce defects.

[0068] Step 1.2: Select appropriate laser power P, scanning speed V, and powder feed rate C. The cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance are the research objectives. For example, P = 1800W, V = 18mm / s, and C = 20g / min.

[0069] Step 1.3: Use grit #320 metallographic sandpaper to coarsely grind the substrate to remove the surface impact layer. Use anhydrous ethanol as solvent to clean it in an ultrasonic cleaner for 15 minutes to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate.

[0070] In step 1.4, 84% FeNiCoCrMo + 15% TiC + 1% Y2O3, 83% FeNiCoCrMo + 15% TiC + 2% Y2O3, and 82% FeNiCoCrMo + 15% TiC + 3% Y2O3 were mixed in a planetary ball mill using ceramic balls at a ball-to-batch ratio of 3:1. The mixture was then ball-milled at 300 r / min for 4 h. After milling, the mixture was dried in a vacuum drying oven at 85°C for 6 h to obtain a composite powder.

[0071] Step 2: Determine laser process parameters Step 2 is as follows: Step 2.1: Place the pretreated substrate 45 steel on the workbench of the laser cladding equipment and perform a single-pass cladding layer experiment on the steel substrate according to the laser process parameters.

[0072] Step 2.2: Cut the single-coat specimen prepared in Step 2.1 in a cross-section perpendicular to the cladding direction. Mount the specimen using a metallographic mounting machine equipped with a hot-mounting resin. Grind with #320 to #2000 metallographic sandpaper, polish with a polishing grinder, and ultrasonically clean in anhydrous ethanol for 15 minutes. Perform a microhardness test on the polished section. Finally, etch the section with aqua regia for 15 seconds, rinse with anhydrous ethanol, dry in a vacuum desiccator, and observe the microstructure.

[0073] Step 2.3. Establish a mapping relationship between laser process parameters and cladding layer quality. Comprehensively analyze the hardness, dilution rate, height, width of the cladding layer under different process parameters, as well as the cross-sectional microstructure after corrosion in step 2.2. Through single-factor experiments, determine the reasonable range of laser power, scanning speed, and powder feeding rate as constraints, and select the optimal process parameters.

[0074] Step 3: Preparation of cladding layer Step 3 is as follows Step 3.1: Use the optimized laser process parameters of step 2.3 and the three composite powders prepared in step 1.4 to carry out laser cladding experiments, and select an overlap rate of 60% to prepare the cladding layer.

[0075] Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer sample into a disc with a diameter of 30 mm, grind it with sandpaper with a grit size of #320-#2000, and polish and etch it.

[0076] Step 4: Test the performance of the cladding layer, as follows Step 4.1: Use a microhardness tester to measure the cross-sectional hardness of the cladding layer and analyze its mechanical properties. The average hardness of the cladding layer with 1% Y2O3 is 948.26 HV, 2% Y2O3 is 974.95 HV, and 3% Y2O3 is 1028.46 HV. The Y2O3 content has a certain effect on the hardness of the coating.

[0077] Step 4.2: Test the tribological properties of the composite coating. A friction and wear tester was used to test the friction coefficient, wear depth and other indicators. Dry friction experiments were conducted to study the tribological properties of the cladding layer when it was worn against different materials. The average friction coefficients of the cladding layers with 1%, 2%, and 3% Y2O3 were 0.51, 0.48, and 0.46, respectively. This shows that increasing the Y2O3 content can reduce the friction coefficient and improve the lubrication performance of the coating. Figure 8 shown.

[0078] Step 4.3: Based on the friction coefficient, wear scar profile, and volume wear rate, the wear mechanism of the cladding layer was revealed. The wear scar width and depth of the 1% Y2O3 cladding layer were approximately 1.12 mm and 6.57 μm, respectively, and the volume wear rate was 9.68×10 -6 mm 3 / N·m. The wear scar width and depth of the 2% Y2O3 cladding layer are approximately 0.98 mm and 6.18 μm, respectively, and the volume wear rate is 7.92×10 -6 mm 3 / N·m. The wear scar width and depth of the 3% Y2O3 cladding layer are approximately 0.92 mm and 5.13 μm, respectively, and the volume wear rate is 6.78×10 -6 mm 3 / N·m. The higher the Y2O3 content, the smaller the volume wear rate and the stronger the wear resistance of the coating. Figure 9 and Figure 10 As shown, Figure 9 is the wear scar profile, Figure 10 is the volume wear rate.

[0079] Example 5 A laser cladding repair process for rocker gears of underground coal mining machines based on the properties of high-entropy alloys enhanced by carbides and rare earth oxides. The following is the laser cladding scheme design and cladding layer preparation process.

[0080] Step 1: Laser Cladding Solution Step 1 is as follows: Step 1.1 Select 45 steel plate as the substrate material with a thickness of 10 mm. The cladding powder is a FeNiCoCrMo high-entropy alloy powder with an approximately equimolar mass ratio. The ceramic hard phase TiC is used as the reinforcement phase to increase the hardness and wear resistance of the composite coating. The rare earth oxide Y2O3 is added to improve the ductility and toughness of the cladding layer and reduce defects.

[0081] Step 1.2: Select appropriate laser power P, scanning speed V, and powder feed rate C. The cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance are the research objectives. For example, P = 1500W, V = 15mm / s, and C = 16g / min.

[0082] Step 1.3: Use grit #320 metallographic sandpaper to coarsely grind the substrate to remove the surface impact layer. Use anhydrous ethanol as solvent to clean it in an ultrasonic cleaner for 15 minutes to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate.

[0083] In step 1.4, mix 82% FeNiCoCrMo, 15% TiC, and 3% Y2O3 in a planetary ball mill using ceramic balls at a ball-to-material ratio of 3:1. Mill the mixture at 300 rpm for 4 hours. After milling, heat the mixture to 85°C in a vacuum drying oven and dry it for 6 hours to obtain a composite powder.

[0084] Step 2: Determine laser process parameters Step 2 is as follows: Step 2.1: Place the pretreated substrate 45 steel on the workbench of the laser cladding equipment and perform a single-pass cladding layer experiment on the steel substrate according to the laser process parameters.

[0085] Step 2.2: Cut the single-coat specimen prepared in Step 2.1 in a cross-section perpendicular to the cladding direction. Mount the specimen using a metallographic mounting machine equipped with a hot-mounting resin. Grind with #320 to #2000 metallographic sandpaper, polish with a polishing grinder, and ultrasonically clean in anhydrous ethanol for 15 minutes. Perform a microhardness test on the polished section. Finally, etch the section with aqua regia for 15 seconds, rinse with anhydrous ethanol, dry in a vacuum desiccator, and observe the microstructure.

[0086] Step 2.3. Establish a mapping relationship between laser process parameters and cladding layer quality. Comprehensively analyze the hardness, dilution rate, height, width of the cladding layer under different process parameters, as well as the cross-sectional microstructure after corrosion in step 2.2. Through single-factor experiments, determine the reasonable range of laser power, scanning speed, and powder feeding rate as constraints, and select the optimal process parameters.

[0087] Step 3: Preparation of cladding layer Step 3 is as follows Step 3.1: Use the optimized laser process parameters of step 2.3 and the three composite powders prepared in step 1.4 to carry out laser cladding experiments, and select an overlap rate of 60% to prepare the cladding layer.

[0088] Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer sample into a disc with a diameter of 30 mm, grind it with sandpaper with a grit size of #320-#2000, and polish and etch it.

[0089] Step 4: Test the performance of the cladding layer, as follows Step 4.1: Use a microhardness tester to measure the cross-sectional hardness of the cladding layer and analyze its mechanical properties. The average hardness of the cladding layer (82% FeNiCoCrMo + 15% TiC + 3% Y2O3) is 780.69 HV, approximately 2.95 times the hardness of the substrate.

[0090] Step 4.2: Test the tribological properties of the composite coating. A friction and wear tester was used to measure the friction coefficient, wear depth, and other indicators. Dry friction experiments were conducted to investigate the tribological properties of the cladding layer when worn against different materials. The average friction coefficient of the cladding layer (82% FeNiCoCrMo + 15% TiC + 3% Y2O3) was 0.58, indicating a reduction in friction compared to the substrate.

[0091] Step 4.3: Based on the friction coefficient, wear scar profile and volume wear rate, the wear mechanism of the cladding layer is revealed. The volume wear rate is 12.58×10 -6 mm 3 / N·m. The wear resistance of the coating is significantly enhanced compared with that of the substrate.

[0092] Example 6 A laser cladding repair process for rocker gears of underground coal mining machines based on the properties of high-entropy alloys enhanced by carbides and rare earth oxides. The following is the laser cladding scheme design and cladding layer preparation process.

[0093] Step 1: Laser Cladding Solution Step 1 is as follows: Step 1.1 Select 45 steel plate as the substrate material with a thickness of 10 mm. The cladding powder is a FeNiCoCrMo high-entropy alloy powder with an approximately equimolar mass ratio. The ceramic hard phase TiC is used as the reinforcement phase to increase the hardness and wear resistance of the composite coating. The rare earth oxide Y2O3 is added to improve the ductility and toughness of the cladding layer and reduce defects.

[0094] Step 1.2: Select appropriate laser power P, scanning speed V, and powder feed rate C. The cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance are the research objectives. For example, P = 2100W, V = 21mm / s, and C = 24g / min.

[0095] Step 1.3: Use grit #320 metallographic sandpaper to coarsely grind the substrate to remove the surface impact layer. Use anhydrous ethanol as solvent to clean it in an ultrasonic cleaner for 15 minutes to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate.

[0096] In step 1.4, mix 82% FeNiCoCrMo, 15% TiC, and 3% Y2O3 in a planetary ball mill using ceramic balls at a ball-to-material ratio of 3:1. Mill the mixture at 300 rpm for 4 hours. After milling, heat the mixture to 85°C in a vacuum drying oven and dry it for 6 hours to obtain a composite powder.

[0097] Step 2: Determine laser process parameters Step 2 is as follows: Step 2.1: Place the pretreated substrate 45 steel on the workbench of the laser cladding equipment and perform a single-pass cladding layer experiment on the steel substrate according to the laser process parameters.

[0098] Step 2.2: Cut the single-coat specimen prepared in Step 2.1 in a cross-section perpendicular to the cladding direction. Mount the specimen using a metallographic mounting machine equipped with a hot-mounting resin. Grind with #320 to #2000 metallographic sandpaper, polish with a polishing grinder, and ultrasonically clean in anhydrous ethanol for 15 minutes. Perform a microhardness test on the polished section. Finally, etch the section with aqua regia for 15 seconds, rinse with anhydrous ethanol, dry in a vacuum desiccator, and observe the microstructure.

[0099] Step 2.3. Establish a mapping relationship between laser process parameters and cladding layer quality. Comprehensively analyze the hardness, dilution rate, height, width of the cladding layer under different process parameters, as well as the cross-sectional microstructure after corrosion in step 2.2. Through single-factor experiments, determine the reasonable range of laser power, scanning speed, and powder feeding rate as constraints, and select the optimal process parameters.

[0100] Step 3: Preparation of cladding layer Step 3 is as follows Step 3.1: Use the optimized laser process parameters of step 2.3 and the three composite powders prepared in step 1.4 to conduct laser cladding experiments, and select an overlap rate of 60% to prepare the cladding layer.

[0101] Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer sample into a disc with a diameter of 30 mm, grind it with sandpaper with a grit size of #320-#2000, and polish and etch it.

[0102] Step 4: Test the performance of the cladding layer, as follows Step 4.1: Use a microhardness tester to measure the cross-sectional hardness of the cladding layer and analyze its mechanical properties. The average hardness of the cladding layer (82% FeNiCoCrMo + 15% TiC + 3% Y2O3) is 735.36 HV, approximately 2.77 times the hardness of the substrate.

[0103] Step 4.2: Test the tribological properties of the composite coating. A friction and wear tester was used to measure the friction coefficient, wear depth, and other indicators. Dry friction experiments were conducted to investigate the tribological properties of the cladding layer when worn against different materials. The average friction coefficient of the cladding layer (82% FeNiCoCrMo + 15% TiC + 3% Y2O3) was 0.61, indicating a reduction in friction compared to the substrate.

[0104] Step 4.3: Based on the friction coefficient, wear scar profile and volume wear rate, the wear mechanism of the cladding layer is revealed. The volume wear rate is 14.16×10 -6 mm 3 / N·m. The wear resistance of the coating is significantly enhanced compared with that of the substrate.

Claims

1. A method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides, characterized in that: Please follow the steps below to implement it: Step 1: Laser cladding scheme design; Step 2: Determine laser process parameters; Step 3: Preparation of cladding layer; Step 4: Testing the performance of the cladding layer.

2. The method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides according to claim 1, characterized in that: The step 1 is specifically implemented according to the following steps: Step 1.1: Select steel plate as the substrate material, and the cladding powder is a high-entropy alloy powder FeCoNiCrMo with an equimolar mass ratio, with a ceramic hard phase TiC as the reinforcement phase to increase the hardness and wear resistance of the composite coating; rare earth oxide Y2O3 is added at a mass fraction of 1-3% to improve the ductility and toughness of the cladding layer and reduce defects; Step 1.2: Set the range of laser power P, scanning speed V, and powder feeding rate C, with the cladding layer aspect ratio, dilution rate, heat-affected zone depth, and cladding layer performance as the research objectives; Step 1.3: Grind the substrate to remove the surface impact layer, use anhydrous ethanol as a solvent, and perform ultrasonic cleaning to remove surface organic matter. Finally, sandblast the substrate surface to improve the bonding strength between the coating and the substrate. Step 1.4: Weigh the cladding powder in step 1 and mix it in a planetary ball mill. Use ceramic balls as the ball milling medium for ball milling. After the ball milling is completed, place it in a vacuum drying oven for heating to obtain a composite powder.

3. The method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides according to claim 2, characterized in that: In the step 1.1, the mass fraction of the high entropy alloy powder FeCoNiCrMo is 82%-94%; the mass fraction of the ceramic hard phase TiC is 5%-15%; and the mass fraction of the rare earth oxide Y2O3 is 1-3%.

4. The method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides according to claim 2, characterized in that: In step 1.2, the laser power P = 1500 W - 2100 W, the scanning speed V = 15 mm / s - 21 mm / s, and the powder feeding rate C = 16 g / min - 24 g / min.

5. The method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides according to claim 2, characterized in that: The ultrasonic cleaning time in step 1.3 is 10 min to 15 min.

6. The method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides according to claim 2, characterized in that: In step 1.4, the ball-to-material ratio is 3-5:1, the ball milling speed is 300 r / min-400 r / min, the ball milling time is 3 h-4 h, the vacuum heating temperature is 80-85° C., and the vacuum heating time is 6-8 h.

7. The method for preparing a high entropy alloy laser cladding coating based on carbides and rare earth oxides according to claim 2, characterized in that: The step 2 is specifically implemented according to the following steps: Step 2.1, perform a single-pass cladding experiment on the pretreated substrate on the steel substrate according to the different laser process parameters selected in step 1.2, with the interval between each two passes being 5-10 mm; Step 2.2: Cut the single-coat coating specimen prepared in step 2.1 on a cross section perpendicular to the cladding direction. Mount the specimen using a metallographic mounting machine equipped with a hot mounting resin, grind and polish it, and ultrasonically clean it in anhydrous ethanol for 10 to 15 minutes. Perform a microhardness test on the polished cross section. Finally, etch the cross section with aqua regia for 15 to 20 seconds, rinse it with anhydrous ethanol, dry it in a vacuum desiccator, and observe the microstructure. Step 2.

3. Establish a mapping relationship between laser process parameters and cladding layer quality. Comprehensively analyze the hardness, dilution rate, height, width of the cladding layer under different process parameters, as well as the cross-sectional microstructure after corrosion in step 2.

2. Determine the reasonable range of laser power, scanning speed, and powder feeding rate as constraints through single-factor experiments to select process parameters.

8. The method for preparing a carbide and rare earth oxide reinforced high entropy alloy laser cladding coating according to claim 7, characterized in that: The process parameters selected in step 2.3 are as follows: The height of the cladding layer is 0.3mm~0.8mm, the width of the cladding layer is 1mm~1.5mm, and the low dilution rate is 10%~25%.

9. The method for preparing a carbide and rare earth oxide reinforced high entropy alloy laser cladding coating according to claim 7, characterized in that: The step 3 is specifically implemented according to the following steps: Step 3.1: Perform a laser cladding experiment using the laser process parameters of step 2.3 and the composite powder prepared in step 1.

4. Select an overlap ratio of 40% to 60% to prepare a cladding layer. Select the number of cladding layers based on the coating thickness requirement of 0.1 to 10 mm. Step 3.2: Allow the sample to cool naturally after cladding to avoid rapid cooling that may cause excessive thermal stress inside the cladding layer, thereby affecting the quality and stability of the cladding layer. Step 3.3: Cut the cladding layer into discs with a diameter of 20 mm to 30 mm, grind and polish them, etch the cross section with aqua regia for 15 s to 20 s, rinse with anhydrous ethanol, and dry in a vacuum dryer to obtain the prepared cladding layer.

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