A method and device for preparing ceramic particle reinforced wear-resistant coating by electron beam surface cladding

Abstract

The present invention belongs to the technical field of high temperature resistant materials, and specifically relates to a method and device for preparing ceramic particle reinforced wear-resistant coating by electron beam surface cladding. Under static magnetic field conditions, the present invention uses ceramic particle reinforced high temperature alloy powder as raw material to perform electron beam surface cladding on the substrate to obtain more excellent corrosion resistance and wear resistance; the present invention can optimize the distribution uniformity and even concentration gradient of carbide ceramics in different depth directions inside the high temperature alloy coating by applying a static magnetic field during the electron beam cladding process, and further improve the interface bonding between the high temperature alloy and the carbide ceramic, reduce the sensitivity to crack generation, and realize the regulation of the microstructure and macrostructure of the high hardness ceramic particle reinforced high temperature alloy coating, thereby improving the comprehensive performance of the material; at the same time, the external static magnetic field can effectively improve the internal organizational morphology of the high temperature alloy, refine the grains, reduce residual stress and pores, and obtain higher mechanical properties.

Description

Technical Field

[0001] The invention belongs to the technical field of high temperature resistant materials, and in particular relates to a method and a device for preparing a ceramic particle reinforced wear-resistant coating by electron beam surface cladding. Background Art

[0002] The iron and steel metallurgical industry has harsh working conditions, such as high temperature and high wear, which puts higher requirements on the surface protection of key mechanical components, such as the high-temperature spiral blades in the environmentally friendly rotary hearth furnace.

[0003] As a new type of material surface modification technology, electron beam surface cladding technology combines the high plasticity and toughness of the base material with the high wear resistance and corrosion resistance of the surface modification layer, thereby greatly improving the overall performance of the material. Compared with other surface modification processes, electron beam surface cladding technology has the advantages of high energy density, fast heating and cooling rates, small base deformation, fine coating grains, and high bonding strength between coating and base, and has good development and application prospects.

[0004] Taking high-hardness ceramic materials such as tungsten carbide (WC) as an example, adding a certain amount of WC powder during the electron beam surface cladding process can significantly improve the hardness and wear resistance of the coating. However, WC has a low formation energy and high thermal conductivity, and is very prone to burnout during the electron beam surface cladding process. Therefore, the WC content in the cladding powder is generally increased to ensure that the target content of WC is retained in the coating. However, WC is highly brittle and has poor wettability. As its content increases, the crack rate of the coating increases, and WC particles are more likely to aggregate, which will reduce the quality of the coating and affect the practical application of the coating.

[0005] Therefore, how to ensure that high-hardness ceramic particles are evenly distributed and free of cracks during the electron beam surface cladding process of the wear-resistant coating of the high-temperature spiral blades of the environmentally friendly rotary hearth furnace is a problem faced by technical personnel in this field. Summary of the invention

[0006] The purpose of the present invention is to provide a method and device for preparing a ceramic particle reinforced wear-resistant coating by electron beam surface cladding. The method for preparing a ceramic particle reinforced wear-resistant coating by electron beam surface cladding provided by the present invention obtains a wear-resistant coating with uniformly distributed high-hardness ceramic particles and no cracks.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention provides a method for preparing a ceramic particle reinforced wear-resistant coating by electron beam surface cladding, comprising the following steps:

[0009] (1) mixing high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0010] The chemical composition of the high temperature alloy powder includes Ni, Cr, Fe, Mo, Nb, Ta and Co;

[0011] The ceramic particles include one or more of tungsten carbide, titanium carbide and titanium nitride;

[0012] (2) Under static magnetic field conditions, the ceramic particle reinforced high temperature alloy powder is used as a raw material to perform electron beam surface cladding on a substrate, thereby obtaining a ceramic particle reinforced wear-resistant coating on the surface of the substrate.

[0013] Preferably, the electron beam surface cladding comprises the following steps: under a static magnetic field condition, adjusting the electron gun and the substrate so that the electron beam of the electron gun is focused on the surface of the substrate, turning on the electron gun to feed the ceramic particle reinforced high temperature alloy powder for electron beam scanning;

[0014] The molten pool obtained by melting the substrate is located at the maximum magnetic field intensity of the static magnetic field.

[0015] Preferably, the static magnetic field is a steady magnetic field; the intensity of the static magnetic field is 0.1-3 T; the direction of the static magnetic field is parallel to the cladding deposition direction of the electron beam surface cladding.

[0016] Preferably, the conditions for the electron beam surface cladding include: the electron beam scanning speed is 3-9 mm / s, the power of the electron gun is 1000-1800 W, the powder feeding gas flow rate is 7-10 L / min, and the electron beam surface cladding is performed under vacuum conditions.

[0017] Preferably, the high-temperature alloy powder and the ceramic particles are independently spherical or nearly spherical; the particle size of the high-temperature alloy powder is 50 to 150 μm; and the particle size of the ceramic particles is 10 to 150 μm.

[0018] Preferably, the static magnetic field condition is provided by a magnet, and the magnet surrounds the electron beam melting head of the electron gun.

[0019] Preferably, the substrate is a high-temperature spiral blade or steel plate of an environmentally friendly rotary hearth furnace.

[0020] The present invention also provides a device for preparing a ceramic particle reinforced wear-resistant coating by electron beam surface cladding, comprising an electron gun, wherein the electron gun comprises an electron beam melting head;

[0021] and a magnet surrounding the electron beam melting head.

[0022] Preferably, the magnet is a spiral magnet; the spiral magnet is an electromagnet.

[0023] Preferably, the electron gun is an axial gun, a non-self-accelerating annular gun, a self-accelerating annular gun or a transverse gun.

[0024] The present invention provides a method for electron beam surface cladding using the device described in the above scheme. The present invention studies the material damage mechanism and failure mode, carries out rational design of high temperature resistant and wear resistant surface coating materials and coating structures, develops high performance electron beam cladding surface coating technology, and controls the coating structure and performance by composite electromagnetic field, overcomes the key technology for preparing long life functional coatings suitable for such vulnerable metallurgical machinery parts, and realizes the long life of the surface of vulnerable metallurgical machinery parts.

[0025] The present invention uses ceramic particle reinforced high temperature alloy powder as raw material to perform electron beam surface cladding on the substrate (such as the high temperature spiral blade of the environmentally friendly rotary furnace, etc.) under static magnetic field conditions to obtain more excellent corrosion resistance and wear resistance; the present invention can optimize the distribution uniformity and even concentration gradient of carbide ceramics in different depth directions inside the high temperature alloy coating by applying a static magnetic field during the electron beam cladding process, gradually make the coating achieve the effects of grain refinement and residual stress suppression, optimize the microstructure and comprehensive performance of the functional gradient coating, and further improve the interface bonding between the high temperature alloy and the carbide ceramic, reduce the sensitivity of crack generation, realize the regulation of the microstructure and macrostructure of the high hardness ceramic particle reinforced high temperature alloy coating, and improve the comprehensive performance of the material; at the same time, the external static magnetic field can effectively improve the internal organizational morphology of the high temperature alloy, refine the grains, reduce residual stress and pores, and obtain higher mechanical properties. In addition, the present invention can effectively deepen the depth of the molten pool and strengthen the bonding strength between the substrate and the reinforcement phase by applying a static magnetic field, thereby realizing the long-term use of the material.

[0026] The present invention also provides a device for preparing a ceramic particle-reinforced wear-resistant coating by electron beam surface cladding, comprising an electron gun and a magnet surrounding the electron beam melting head of the electron gun. The device provided by the present invention can regulate the alloy melt in the electron beam surface cladding by arranging magnets around the electron beam melting head to generate a static magnetic field, thereby avoiding the Marangoni thermal convection effect (the effect of the melt in the molten pool flowing from the high-temperature part to the low-temperature part, that is, the phenomenon of flowing from the center of the molten pool to the surroundings), and micro-regulating the melt flow, thereby achieving the regulation of the microstructure and macro-organization of the ceramic-reinforced high-temperature alloy coating, improving its comprehensive performance, and thus obtaining a wear-resistant coating with uniform distribution of high-hardness ceramic particles and no cracks. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 A schematic diagram of the structure of the device for preparing a ceramic particle-reinforced wear-resistant coating by electron beam surface cladding provided by the present invention; wherein 1 is an electron beam cladding head, 2 is a clamping plate, 3 is an electromagnet, and 4 is a substrate;

[0029] Figure 2 It is a high-temperature spiral blade of the environmentally friendly rotary hearth furnace used in the present invention; wherein 5 is a spiral blade and 6 is a rotating shaft;

[0030] Figure 3 The morphology observation diagram of the ceramic particle reinforced wear-resistant coating prepared in Examples 2 to 16 of the present invention;

[0031] Figure 4 The steel material coated with ceramic particle reinforced wear-resistant coating prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0032] The present invention provides a method for preparing a ceramic particle reinforced wear-resistant coating by electron beam surface cladding, comprising the following steps:

[0033] (1) mixing high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0034] The chemical composition of the high temperature alloy powder includes Ni, Cr, Fe, Mo, Nb, Ta and Co;

[0035] The ceramic particles include one or more of tungsten carbide, titanium carbide and titanium nitride;

[0036] (2) Under static magnetic field conditions, the ceramic particle reinforced high temperature alloy powder is used as a raw material to perform electron beam surface cladding on a substrate, thereby obtaining a ceramic particle reinforced wear-resistant coating on the surface of the substrate.

[0037] The present invention mixes high-temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high-temperature alloy powder. In the present invention, the high-temperature alloy is preferably spherical or nearly spherical; the chemical composition of the high-temperature alloy powder includes Ni, Cr, Fe, Mo, Nb, Ta and Co; in terms of atomic percentage, the chemical composition of the high-temperature alloy powder preferably includes Cr20-23%, more preferably 21-22%, and further preferably 21.5%; in terms of atomic percentage, the chemical composition of the high-temperature alloy powder preferably includes Fe not higher than 5%, more preferably 1-4%, and further preferably 2-3%; in terms of atomic percentage, the chemical composition of the high-temperature alloy powder preferably includes Mo8-10%, and more preferably 8.5-9.5 %, and more preferably 9%; in terms of atomic percentage, the chemical composition of the high-temperature alloy powder preferably includes Nb3.15-4.15%, more preferably 3.3-4%, and more preferably 3.5-3.8%; in terms of atomic percentage, the chemical composition of the high-temperature alloy powder preferably includes Ta not higher than 0.4%, and more preferably 0.1-0.3%; in terms of atomic percentage, the chemical composition of the high-temperature alloy powder preferably includes Co0.8-1.2%, and more preferably 0.9-1.1%, and more preferably 1%; in terms of atomic percentage, the chemical composition of the high-temperature alloy powder preferably includes Ni balance.

[0038] In the present invention, the particle size of the high temperature alloy powder is preferably 50 to 150 μm, more preferably 70 to 120 μm, and further preferably 90 to 100 μm; the D 50 The particle size is preferably 80-100 μm, more preferably 90 μm. In a specific embodiment of the present invention, the high temperature alloy is preferably Inconel 625 alloy.

[0039] In the present invention, the ceramic particles are preferably spherical or nearly spherical; the ceramic particles preferably include one or more of tungsten carbide, titanium carbide and titanium nitride; the particle size of the ceramic particles is preferably 10 to 150 μm, more preferably 30 to 120 μm, and further preferably 60 to 90 μm; the mass ratio of the high-temperature alloy powder and the ceramic particles is preferably 6.0 to 9.5:0.5 to 4.0, and more preferably 8.5 to 9.0:1.0 to 1.5.

[0040] In the present invention, the ceramic particle reinforced high-temperature alloy powder is preferably dried before the electron beam surface cladding; the drying equipment is preferably a vacuum oven; the drying temperature is preferably 40-50°C, more preferably 43-48°C, and the holding time is preferably 290-310min, more preferably 295-300min.

[0041] After obtaining the ceramic particle reinforced high temperature alloy powder, the present invention uses the ceramic particle reinforced high temperature alloy powder as a raw material to perform electron beam surface cladding on the substrate under static magnetic field conditions, and obtains a ceramic particle reinforced wear-resistant coating on the substrate surface. In the present invention, the static magnetic field is preferably a steady magnetic field; the intensity of the static magnetic field is preferably 0.1 to 3T, more preferably 0.5 to 2.5T, and further preferably 1 to 2T; the direction of the static magnetic field is preferably parallel to the cladding deposition direction of the electron beam surface cladding.

[0042] In the present invention, the electron beam surface cladding preferably includes the following steps: under static magnetic field conditions, adjusting the electron gun and the substrate so that the electron beam of the electron gun is focused on the surface of the substrate, turning on the electron gun to feed the ceramic particle reinforced high-temperature alloy powder for electron beam scanning; the molten pool obtained by melting the substrate is located at the maximum magnetic field intensity of the static magnetic field; the substrate is preferably a high-temperature spiral blade or steel plate of an environmentally friendly rotary hearth furnace; the steel plate is preferably a 316L steel plate; the size of the steel plate is preferably 35mm×100mm; before the electron beam surface cladding, the substrate is preferably sandblasted and cleaned in sequence; the cleaning agent is preferably ethanol; the powder feeding rate is preferably 2-5g / min, more preferably 3-4g / min; the powder feeding method is preferably coaxial powder feeding; when the substrate is a high-temperature spiral blade, the electron beam surface cladding is preferably carried out on the spiral surface and the material-facing surface of the high-temperature spiral blade, and the structure of the high-temperature spiral blade is as follows Figure 2 As shown; the plasma energy received by the ceramic particle reinforced high-temperature alloy powder during the electron beam surface cladding process is preferably 90-110J, more preferably 95-105J; the conditions for the electron beam surface cladding preferably include: the electron beam scanning speed is preferably 3-9mm / s, more preferably 5-7mm / s, the power of the electron gun is preferably 1000-1800W, more preferably 1200-1500W, the powder feeding gas flow rate is preferably 7-10L / min, more preferably 8-9L / min, and the electron beam surface cladding is preferably carried out under vacuum conditions; the static magnetic field conditions are preferably provided by a magnet, and the magnet is preferably surrounded by the electron beam melting head of the electron gun.

[0043] In the present invention, the electron beam scanning preferably includes the following steps: (1) moving the electron gun along a set path to obtain a first cladding layer; (2) lifting the electron beam of the electron gun and moving it along a set path to obtain a second cladding layer; (3) repeating the step (2) to obtain a ceramic particle reinforced wear-resistant coating; the lifting amount of the electron beam is preferably 0.75 to 1.25 mm, more preferably 1 mm; the number of repetitions of the step (2) is preferably 1 to 4 times, more preferably 2 to 3 times. In the electron beam surface cladding process of the present invention, part of the ceramic particle reinforced high-temperature alloy powder will melt above the electron beam focusing position to form metal droplets that fall into the molten pool, which does not affect the forming process.

[0044] The present invention also provides a device for preparing a ceramic particle reinforced wear-resistant coating by electron beam surface cladding, comprising an electron gun, wherein the electron gun comprises an electron beam melting head;

[0045] and a magnet surrounding the electron beam melting head.

[0046] In the present invention, the magnet is preferably a spiral magnet; the spiral magnet is preferably an electromagnet; the spiral magnet is preferably a spiral coil; the electron gun is preferably an axial gun, a non-self-accelerating annular gun, a self-accelerating annular gun or a transverse gun, and the specific structure is as follows: Figure 1 shown.

[0047] In order to further illustrate the present invention, the scheme of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments, but they should not be understood as limiting the protection scope of the present invention.

[0048] Example 1

[0049] (1) The high temperature alloy is Inconel625 alloy. The atomic percentage of the alloy powder is: 58% Ni, 20% Cr, 5% Fe, 8% Mo, 4% Nb, 0.4% Ta, 1% Co, and the balance is inevitable impurities. The particle size distribution range of the alloy powder is 50-150 μm. 50 90μm; ceramic particles are WC, with a particle size of 10-150μm;

[0050] Mixing the high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0051] The ceramic particle reinforced high temperature alloy powder is placed in a vacuum oven and baked at 45° C. for 5 hours to obtain a dry ceramic particle reinforced high temperature alloy powder;

[0052] (2) A 316L steel plate of 35 mm × 100 mm was selected, the steel plate was sandblasted and then cleaned with ethanol to obtain a 316L steel plate substrate with a smooth and clean surface;

[0053] (3) Place the dried ceramic particle reinforced high-temperature alloy powder into the powder bin and then into the powder feeding module, adjust the powder feeding rate to 3 g / min, adjust the relative position of the electron gun and the substrate so that the electron beam is focused on the surface of the substrate, surround the energized spiral coil around the electron gun and adjust its height, and the magnetic field strength is 0.5 T; set the electron beam scanning speed to 3 mm / s, the electron gun power to 800 W, the powder feeding gas flow rate to 6 L / min, and the electron gun lift to 1 mm;

[0054] (4) Turn on the electron gun, and the electron beam melts the substrate to form a molten pool of a certain size, so that the molten pool is located at the maximum magnetic field intensity, and at the same time, the Inconel625 alloy and WC ceramic particle reinforced high-temperature alloy powder are transported into the molten pool by a coaxial powder feeding method, and the electron gun moves according to the set scanning path to form the first layer of cladding layer;

[0055] (5) immediately starting a second cladding process after raising the electron beam of the electron gun by 1 mm, wherein the parameters of the second cladding process are consistent with those of step (4);

[0056] (6) Repeat step (5) 3 times to obtain a ceramic particle reinforced wear-resistant coating on the substrate surface, the appearance of which is as follows: Figure 3 shown.

[0057] Example 2

[0058] (1) The high temperature alloy is Inconel625 alloy. The atomic percentage of the alloy powder is: 58% Ni, 20% Cr, 5% Fe, 8% Mo, 4% Nb, 0.4% Ta, 1% Co, and the balance is inevitable impurities. The particle size distribution range of the alloy powder is 50-150 μm. 50 90μm; ceramic particles are WC, with a particle size of 10-150μm;

[0059] Mixing the high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0060] The ceramic particle reinforced high temperature alloy powder is placed in a vacuum oven and baked at 45° C. for 5 hours to obtain a dry ceramic particle reinforced high temperature alloy powder;

[0061] (2) A 316L steel plate of 35 mm × 100 mm was selected, the steel plate was sandblasted and then cleaned with ethanol to obtain a 316L steel plate substrate with a smooth and clean surface;

[0062] (3) Place the dried ceramic particle reinforced high-temperature alloy powder into the powder bin and then into the powder feeding module, adjust the powder feeding rate to 3 g / min, adjust the relative position of the electron gun and the substrate so that the electron beam is focused on the surface of the substrate, surround the energized spiral coil around the electron gun and adjust its height, and the magnetic field strength is 0.3 T; set the electron beam scanning speed to 3 mm / s, the electron gun power to 1000 W, the powder feeding gas flow rate to 6 L / min, and the electron gun lift to 1 mm;

[0063] (4) Turn on the electron gun, and the electron beam melts the substrate to form a molten pool of a certain size, so that the molten pool is located at the maximum magnetic field intensity, and at the same time, the Inconel625 alloy and WC ceramic particle reinforced high-temperature alloy powder are transported into the molten pool by a coaxial powder feeding method, and the electron gun moves according to the set scanning path to form the first layer of cladding layer;

[0064] (5) immediately starting a second cladding process after raising the electron beam of the electron gun by 1 mm, wherein the parameters of the second cladding process are consistent with those of step (4);

[0065] (6) Repeat step (5) three times to obtain a ceramic particle reinforced wear-resistant coating on the substrate surface.

[0066] Example 3

[0067] (1) The high temperature alloy is Inconel625 alloy. The atomic percentage of the alloy powder is: 58% Ni, 20% Cr, 5% Fe, 8% Mo, 4% Nb, 0.4% Ta, 1% Co, and the balance is inevitable impurities. The particle size distribution range of the alloy powder is 50-150 μm. 50 90μm; ceramic particles are WC, with a particle size of 10-150μm;

[0068] Mixing the high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0069] The ceramic particle reinforced high temperature alloy powder is placed in a vacuum oven and baked at 45° C. for 5 hours to obtain a dry ceramic particle reinforced high temperature alloy powder;

[0070] (2) A 316L steel plate of 35 mm × 100 mm was selected, the steel plate was sandblasted and then cleaned with ethanol to obtain a 316L steel plate substrate with a smooth and clean surface;

[0071] (3) Place the dried ceramic particle reinforced high-temperature alloy powder into the powder bin and then into the powder feeding module, adjust the powder feeding rate to 3 g / min, adjust the relative position of the electron gun and the substrate so that the electron beam is focused on the surface of the substrate, surround the energized spiral coil around the electron gun and adjust its height, and the magnetic field strength is 0.3 T; set the electron beam scanning speed to 3 mm / s, the electron gun power to 1200 W, the powder feeding gas flow rate to 6 L / min, and the electron gun lift to 1 mm;

[0072] (4) Turn on the electron gun, and the electron beam melts the substrate to form a molten pool of a certain size, so that the molten pool is located at the maximum magnetic field intensity, and at the same time, the Inconel625 alloy and WC ceramic particle reinforced high-temperature alloy powder are transported into the molten pool by a coaxial powder feeding method, and the electron gun moves according to the set scanning path to form the first layer of cladding layer;

[0073] (5) immediately starting a second cladding process after raising the electron beam of the electron gun by 1 mm, wherein the parameters of the second cladding process are consistent with those of step (4);

[0074] (6) Repeat step (5) three times to obtain a ceramic particle reinforced wear-resistant coating on the substrate surface.

[0075] Example 4

[0076] (1) The high temperature alloy is Inconel625 alloy. The atomic percentage of the alloy powder is: 58% Ni, 20% Cr, 5% Fe, 8% Mo, 4% Nb, 0.4% Ta, 1% Co, and the balance is inevitable impurities. The particle size distribution range of the alloy powder is 50-150 μm. 50 90μm; ceramic particles are WC, with a particle size of 10-150μm;

[0077] Mixing the high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0078] The ceramic particle reinforced high temperature alloy powder is placed in a vacuum oven and baked at 45° C. for 5 hours to obtain a dry ceramic particle reinforced high temperature alloy powder;

[0079] (2) A 316L steel plate of 35 mm × 100 mm was selected, the steel plate was sandblasted and then cleaned with ethanol to obtain a 316L steel plate substrate with a smooth and clean surface;

[0080] (3) Place the dried ceramic particle reinforced high-temperature alloy powder into the powder bin and then into the powder feeding module, adjust the powder feeding rate to 3 g / min, adjust the relative position of the electron gun and the substrate so that the electron beam is focused on the surface of the substrate, surround the energized spiral coil around the electron gun and adjust its height, and the magnetic field strength is 0.3 T; set the electron beam scanning speed to 3 mm / s, the electron gun power to 1400 W, the powder feeding gas flow rate to 6 L / min, and the electron gun lift to 1 mm;

[0081] (4) Turn on the electron gun, and the electron beam melts the substrate to form a molten pool of a certain size, so that the molten pool is located at the maximum magnetic field intensity, and at the same time, the Inconel625 alloy and WC ceramic particle reinforced high-temperature alloy powder are transported into the molten pool by a coaxial powder feeding method, and the electron gun moves according to the set scanning path to form the first layer of cladding layer;

[0082] (5) immediately starting a second cladding process after raising the electron beam of the electron gun by 1 mm, wherein the parameters of the second cladding process are consistent with those of step (4);

[0083] (6) Repeat step (5) three times to obtain a ceramic particle reinforced wear-resistant coating on the substrate surface.

[0084] Embodiments 5 to 16

[0085] The preparation methods of Examples 5 to 16 are the same as those of Example 1, except that the differences are shown in Table 1:

[0086] Table 1 Electron gun power and powder feeding rate of Examples 5 to 16

[0087]

[0088]

[0089] Comparative Example 1

[0090] (1) The high temperature alloy is Inconel625 alloy. The atomic percentage of the alloy powder is: 58% Ni, 20% Cr, 5% Fe, 8% Mo, 4% Nb, 0.4% Ta, 1% Co, and the balance is inevitable impurities. The particle size distribution range of the alloy powder is 50-150 μm. 50 90μm; ceramic particles are WC, with a particle size of 10-150μm;

[0091] Mixing the high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0092] The ceramic particle reinforced high temperature alloy powder is placed in a vacuum oven and baked at 45° C. for 5 hours to obtain a dry ceramic particle reinforced high temperature alloy powder;

[0093] (2) A 316L steel plate of 35 mm × 100 mm was selected, the steel plate was sandblasted and then cleaned with ethanol to obtain a 316L steel plate substrate with a smooth and clean surface;

[0094] (3) Place the dried ceramic particle reinforced high-temperature alloy powder into the powder bin and then into the powder feeding module, adjust the powder feeding rate to 3 g / min, adjust the relative position of the electron gun and the substrate so that the electron beam is focused on the surface of the substrate, surround the energized spiral coil around the electron gun and adjust its height, and the magnetic field strength is 0 T; set the electron beam scanning speed to 3 mm / s, the electron gun power to 1000 W, the powder feeding gas flow rate to 6 L / min, and the electron gun lift to 1 mm;

[0095] (4) Turn on the electron gun, and the electron beam melts the substrate to form a molten pool of a certain size, so that the molten pool is located at the maximum magnetic field intensity, and at the same time, the Inconel625 alloy and WC ceramic particle reinforced high-temperature alloy powder are transported into the molten pool by a coaxial powder feeding method, and the electron gun moves according to the set scanning path to form the first layer of cladding layer;

[0096] (5) immediately starting a second cladding process after raising the electron beam of the electron gun by 1 mm, wherein the parameters of the second cladding process are consistent with those of step (4);

[0097] (6) Repeat step (5) three times to obtain a ceramic particle reinforced wear-resistant coating on the substrate surface.

[0098] Comparative Example 2

[0099] (1) The high temperature alloy is Inconel625 alloy. The atomic percentage of the alloy powder is: 58% Ni, 20% Cr, 5% Fe, 8% Mo, 4% Nb, 0.4% Ta, 1% Co, and the balance is inevitable impurities. The particle size distribution range of the alloy powder is 50-150 μm. 50 90μm; ceramic particles are WC, with a particle size of 10-150μm;

[0100] Mixing the high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0101] The ceramic particle reinforced high temperature alloy powder is placed in a vacuum oven and baked at 45° C. for 5 hours to obtain a dry ceramic particle reinforced high temperature alloy powder;

[0102] (2) A 316L steel plate of 35 mm × 100 mm was selected, the steel plate was sandblasted and then cleaned with ethanol to obtain a 316L steel plate substrate with a smooth and clean surface;

[0103] (3) Place the dried ceramic particle reinforced high-temperature alloy powder into the powder bin and then into the powder feeding module, adjust the powder feeding rate to 3 g / min, adjust the relative position of the electron gun and the substrate so that the electron beam is focused on the surface of the substrate, surround the energized spiral coil around the electron gun and adjust its height, and the magnetic field strength is 0 T; set the electron beam scanning speed to 3 mm / s, the electron gun power to 1200 W, the powder feeding gas flow rate to 6 L / min, and the electron gun lift amount to 1 mm;

[0104] (4) Turn on the electron gun, and the electron beam melts the substrate to form a molten pool of a certain size, so that the molten pool is located at the maximum magnetic field intensity, and at the same time, the Inconel625 alloy and WC ceramic particle reinforced high-temperature alloy powder are transported into the molten pool by a coaxial powder feeding method, and the electron gun moves according to the set scanning path to form the first layer of cladding layer;

[0105] (5) immediately starting a second cladding process after raising the electron beam of the electron gun by 1 mm, wherein the parameters of the second cladding process are consistent with those of step (4);

[0106] (6) Repeat step (5) three times to obtain a ceramic particle reinforced wear-resistant coating on the substrate surface.

[0107] Comparative Example 3

[0108] (1) The high temperature alloy is Inconel625 alloy. The atomic percentage of the alloy powder is: 58% Ni, 20% Cr, 5% Fe, 8% Mo, 4% Nb, 0.4% Ta, 1% Co, and the balance is inevitable impurities. The particle size distribution range of the alloy powder is 50-150 μm. 50 90μm; ceramic particles are WC, with a particle size of 10-150μm;

[0109] Mixing the high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder;

[0110] The ceramic particle reinforced high temperature alloy powder is placed in a vacuum oven and baked at 45° C. for 5 hours to obtain a dry ceramic particle reinforced high temperature alloy powder;

[0111] (2) A 316L steel plate of 35 mm × 100 mm was selected, the steel plate was sandblasted and then cleaned with ethanol to obtain a 316L steel plate substrate with a smooth and clean surface;

[0112] (3) Place the dried ceramic particle reinforced high-temperature alloy powder into the powder bin and then into the powder feeding module, adjust the powder feeding rate to 3 g / min, adjust the relative position of the electron gun and the substrate so that the electron beam is focused on the surface of the substrate, surround the energized spiral coil around the electron gun and adjust its height, and the magnetic field strength is 0 T; set the electron beam scanning speed to 3 mm / s, the electron gun power to 1400 W, the powder feeding gas flow rate to 6 L / min, and the electron gun lift to 1 mm;

[0113] (4) Turn on the electron gun, and the electron beam melts the substrate to form a molten pool of a certain size, so that the molten pool is located at the maximum magnetic field intensity, and at the same time, the Inconel625 alloy and WC ceramic particle reinforced high-temperature alloy powder are transported into the molten pool by a coaxial powder feeding method, and the electron gun moves according to the set scanning path to form the first layer of cladding layer;

[0114] (5) immediately starting a second cladding process after raising the electron beam of the electron gun by 1 mm, wherein the parameters of the second cladding process are consistent with those of step (4);

[0115] (6) Repeat step (5) three times to obtain a ceramic particle reinforced wear-resistant coating on the substrate surface.

[0116] The density of the ceramic particle reinforced wear-resistant coatings prepared in Examples 2 to 4 of the present invention and Comparative Examples 1 to 3 was statistically analyzed. The sum of the porosity and the density was equal to 1. The results are shown in Table 2.

[0117] Table 2 Density of ceramic particle reinforced wear-resistant coating under different power and magnetic field

[0118]

[0119] According to Table 2, under the same electron gun power, the ceramic particle reinforced wear-resistant coating prepared by the embodiment of the present invention has a high density, which is above 97%, and can even reach 99.1288%. This is because the external magnetic field of the present invention assists in changing the stress state, thereby reducing the porosity of the coating and increasing the density of the coating; for the same powder feeding rate, the high porosity caused by the higher feeding rate can be reduced by increasing the laser power. It can be seen that the ceramic particle reinforced wear-resistant coating prepared by the present invention has good density, which is conducive to better protection of the substrate components;

[0120] In the embodiment of the present invention, the ceramic particle reinforced wear-resistant coating is prepared. The greater the laser power of the electron gun, the greater the WC particle content. However, too high a laser power may cause the WC particles to partially dissolve in the molten pool.

[0121] Under the same electron gun laser power, the microhardness of the ceramic particle reinforced wear-resistant coating prepared by applying a magnetic field in the embodiment of the present invention is significantly higher than that of the ceramic particle reinforced wear-resistant coating prepared without applying a magnetic field.

[0122] The morphology of the ceramic particle reinforced wear-resistant coatings prepared in Examples 2 to 16 of the present invention was observed using a scanning electron microscope. The results are as follows: Figure 4 As shown. Figure 4 It can be seen that the ceramic particle reinforced wear-resistant coating prepared in the embodiment of the present invention has uniform high-hardness ceramic particles, a complete structure, and a coating without cracks and obvious defects.

[0123] It can be seen from the above embodiments that the ceramic particle reinforced wear-resistant coating prepared by the method provided by the present invention has uniform distribution of high-hardness ceramic particles, no cracks in the coating, high hardness, good wear resistance and dense structure.

[0124] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preparing a ceramic particle reinforced wear-resistant coating by electron beam surface cladding, comprising the following steps: (1) mixing high temperature alloy powder and ceramic particles to obtain ceramic particle reinforced high temperature alloy powder; The chemical composition of the high temperature alloy powder includes Ni, Cr, Fe, Mo, Nb, Ta and Co; The ceramic particles include one or more of tungsten carbide, titanium carbide and titanium nitride; (2) Under static magnetic field conditions, the ceramic particle reinforced high temperature alloy powder is used as a raw material to perform electron beam surface cladding on a substrate, thereby obtaining a ceramic particle reinforced wear-resistant coating on the surface of the substrate; The electron beam surface cladding comprises the following steps: under a static magnetic field condition, adjusting an electron gun and a substrate so that the electron beam of the electron gun is focused on the surface of the substrate, turning on the electron gun to feed the ceramic particle reinforced high temperature alloy powder for electron beam scanning; The molten pool obtained by melting the substrate is located at the maximum magnetic field intensity of the static magnetic field; The direction of the static magnetic field is parallel to the cladding deposition direction of the electron beam surface cladding; The electron beam surface cladding is performed under vacuum conditions; The static magnetic field condition is provided by a magnet, and the magnet surrounds the electron beam melting head of the electron gun; The chemical composition of the high temperature alloy powder includes, in terms of atomic percentage, Cr 20-23%, Fe not higher than 5%, Mo 8-10%, Nb 3.15-4.15%, Ta not higher than 0.4%, Co 0.8-1.2%, and Ni balance; The mass ratio of the high temperature alloy powder to the ceramic particles is 6.0-9.5:0.5-4.

0.

2. The method according to claim 1, characterized in that The static magnetic field is a steady magnetic field; the intensity of the static magnetic field is 0.1~3 T.

3. The method according to claim 1, characterized in that The conditions for the electron beam surface cladding include: the electron beam scanning speed is 3-9 mm / s, the electron gun power is 1000-1800 W, and the powder feeding gas flow rate is 7-10 L / min.

4. The method according to claim 1, characterized in that: The high-temperature alloy powder and the ceramic particles are independently spherical or nearly spherical; the particle size of the high-temperature alloy powder is 50-150 μm; and the particle size of the ceramic particles is 10-150 μm.

5. The method according to claim 1, characterized in that The substrate is a high-temperature spiral blade or steel plate of an environmentally friendly rotary hearth furnace.

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