A method for repairing a metal target

Abstract

A metal target repair method is used to repair a molybdenum-tungsten alloy target, including: cleaning and grinding of the metal target, initialization of the laser cladding equipment and the powder feeding device; laser cladding in a progressive layer-by-layer manner based on a preset cross-scanning path; grinding the surface of the cladding layer after cooling, thus completing the repair of the metal target. The present invention forms a smaller molten pool by setting a cross-scanning path to perform laser cladding in a progressive layer-by-layer manner, effectively restricting the flow of the molybdenum-tungsten alloy, reducing the heat-affected zone, avoiding target performance degradation, thermal stress and deformation, and reducing the risk of local cracking.

Description

Technical Field

[0001] The invention relates to the field of metal target materials, and in particular to a method for repairing a metal target material. Background Art

[0002] With the rapid development of science and technology, molybdenum-tungsten alloys are widely used in high-tech fields such as semiconductor manufacturing, optoelectronic devices, solar cells, etc. due to their excellent physical and chemical properties. These fields have strict requirements on the high strength, high melting point and good conductivity of materials. Molybdenum-tungsten alloy targets have become ideal materials for manufacturing high-performance films and coatings due to their high melting point (the melting point of tungsten is 3422℃) and excellent mechanical properties. However, during long-term use, the surface of the target will be damaged and worn, affecting its performance and service life.

[0003] In current technology, the main technical methods for repairing molybdenum-tungsten alloy targets include laser cladding, cold spraying, brush plating, etc. Taking laser cladding as an example, it is a method of using a high-energy laser beam to form a molten pool on the surface of the substrate, and at the same time spraying molybdenum-tungsten alloy powder into the molten pool through a powder feeding system to melt it and combine it with the substrate, and then form a dense repair layer after cooling.

[0004] Molybdenum (Mo) is a metal with many excellent properties and is widely used in the manufacture of metal targets. In many high-tech fields, molybdenum targets are widely used due to their unique properties and advantages, such as in the manufacture of optical thin films and reflector coatings, interconnect layer materials in integrated circuits and large-scale integrated circuits (VLSI), and back electrode materials in thin-film solar cells, such as copper indium gallium selenide (CIGS) and copper zinc tin sulfur (CZTS) solar cells.

[0005] In the application scenario of the present invention, in order to improve the strength and stability of molybdenum in high temperature environment and prevent deformation caused by thermal stress; at the same time, to reduce the thermal expansion coefficient of molybdenum so that it can better match other layer materials of solar cells (such as copper indium gallium selenide and copper zinc tin sulfur thin film solar cells) to reduce interface stress, a small amount of tungsten is usually added to molybdenum. Molybdenum and tungsten both belong to the 6th group transition metals and have similar chemical properties. Among them, the melting point of molybdenum is 2623℃, while tungsten has the highest melting point of all metals at 3422℃.

[0006] In some embodiments, especially when producing CIGS (copper indium gallium selenide) solar cells, in order to increase the corrosion resistance and oxidation resistance of the film, while reducing the resistance inside the film and improving the conductivity of the film, the proportion of tungsten doping is usually between 5% and 10%.

[0007] However, there are two problems with the above method. First, due to the high melting point of tungsten, the heat affected zone expands, causing the performance of the target material to deteriorate (such as a decrease in hardness and strength), which in turn leads to thermal stress and deformation, and may even cause local cracking of the target material. Secondly, due to the large difference in the melting points of the alloys, the molybdenum-tungsten powder will be unevenly distributed in the cladding layer during the high-temperature cladding process, thus affecting the consistency of the material. Summary of the invention

[0008] Based on this, it is necessary to propose a method for repairing metal targets in response to the above technical problems.

[0009] The present invention adopts the following technical solution.

[0010] The first aspect of the present invention discloses a method for repairing a metal target material, which is used for repairing a molybdenum-tungsten alloy target material, and is characterized in that the method comprises steps S1 to S3;

[0011] Step S1, cleaning and grinding of the metal target, and initialization of the laser cladding equipment and the powder feeding device;

[0012] Step S2, performing laser cladding in a progressive layer-by-layer manner based on a preset cross scanning path;

[0013] The cross scanning path is the scanning path of the laser cladding equipment, covering the entire area to be repaired, including the first path and the second path. The first path and the second path present a cross path structure. The width of the path is shown in the following formula:

[0014] ,

[0015] in, is the width of the path, is the spot diameter of the laser cladding equipment, is the correction factor, is the scanning rate, is the overlap ratio of the cross-scan paths;

[0016] Step S3, grinding the surface of the cladding layer after cooling, thus completing the repair of the metal target.

[0017] Furthermore, step S1 specifically includes: using an organic solvent to clean the surface of the molybdenum-tungsten alloy target to remove grease, dust and other contaminants; using fine sandpaper to polish the surface of the target to remove the oxide layer and loose particles; the laser cladding equipment is set to a fiber laser or a carbon dioxide laser, the power range is set to 1kw-2kw, the scanning speed is set to 5-20mm / s, and the spot diameter is set to 1.5-2mm; the particle size of the molybdenum-tungsten alloy powder is 25-35 microns, the purity is greater than 99.9%, and the rate is set to 5-20g / min; the protective gas is selected as argon, which is mixed in the molybdenum-tungsten alloy powder to prevent the molybdenum-tungsten alloy powder from oxidizing during the cladding process, and its flow rate is set to 10-20 L / min.

[0018] Furthermore, laser cladding specifically forms a molten pool on the surface of the target material through a high-energy laser beam, and at the same time, molybdenum-tungsten alloy powder is fed into the molten pool through a powder feeding device to melt it and combine with the target material to form a dense coating, thereby achieving the purpose of repairing the target material.

[0019] Further, the cross scanning path preset in step S2 is set based on steps S21 to S24;

[0020] Step S21, setting a preliminary scanning trajectory;

[0021] Step S22, determining a 3D model of the area to be repaired, and using it to calculate the depth of each location in the area to be repaired;

[0022] Step S23, determining the scanning rate and the width of the path at each location in the area to be repaired based on the depth of each location in the area to be repaired;

[0023] Step S24, determining a preset cross scanning path based on the scanning rate and the width of the path at each location in the area to be repaired.

[0024] Furthermore, step S22 specifically includes: first, cleaning the area to be repaired to ensure that there is no oil, dust and other pollutants; second, applying the filling material evenly to the area to be repaired to ensure that all recessed and uneven areas are filled, and allowing the filling material to fully solidify according to the characteristics of the filling material. After taking out the filling material, finally determine the 3D model of the area to be repaired according to the 3D scanner, and use it to calculate the depth of each point in the area to be repaired.

[0025] Further, in step S23, the scanning rate of each location in the area to be repaired is As shown below:

[0026] ,

[0027] in, is the two-dimensional position of the area to be repaired, In the area to be repaired The depth of the location and the area to be repaired The depth at the location, is the laser power, express The average depth at the location, is a fixed constant.

[0028] Further, step S23 specifically includes step S231 to step S233;

[0029] Step S231, determining a plurality of equipotential lines in the area to be repaired based on the depth of each location in the area to be repaired;

[0030] Step S232, based on the equipotential lines, calculating the average depth of each location in each area to be repaired;

[0031] Step S233, based on the average depth of each location in the area to be repaired, determine the scanning rate and the width of the path at each location in the area to be repaired.

[0032] Furthermore, in each area to be repaired Average depth at location As shown below:

[0033] ,

[0034] in, Indicates The depth of the equipotential lines, express With The vertical distance between the equipotential lines.

[0035] The present invention has the following advantages:

[0036] The present invention sets a cross scanning path and performs laser cladding in a progressive layer-by-layer manner to form a smaller molten pool, which effectively limits the flow of molybdenum-tungsten alloy, reduces the heat-affected zone, avoids target material performance degradation, thermal stress and deformation, and reduces the risk of local cracking. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 The present invention is a flow chart of a method for repairing a metal target.

[0039] Figure 2 is a top view of a cross-scan path according to an embodiment of the present invention.

[0040] Figure 3 yes Figure 2 A side perspective view of the associated multi-layer intersecting scan paths.

[0041] Figure 4 It is a top view of the cross scanning path in the prior art.

[0042] Figure 5 Schematic diagram of equipotential lines according to an embodiment of the present invention.

[0043] Figure 6 Schematic diagram of a cross scan path according to an embodiment of the present invention.

[0044] Figure 7 Schematic diagram of the Raman spectrum of the area to be repaired according to an embodiment of the present invention.

[0045] Figure 8 It is a schematic diagram of the Raman spectrum of the area to be repaired in the prior art. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] Based on this, the present invention discloses a metal target repair method for repairing a molybdenum-tungsten alloy target, such as Figure 1 The repair method may include steps S1 to S3.

[0048] Step S1, cleaning and grinding of the metal target, and initialization of the laser cladding equipment and the powder feeding device.

[0049] In some embodiments, the surface of the molybdenum-tungsten alloy target can be thoroughly cleaned with an organic solvent (such as isopropyl alcohol or ethanol) to remove grease, dust and other contaminants. A clean dust-free cloth or wipe paper should be used during the cleaning process to ensure that the surface is clean and free of residue.

[0050] Use fine sandpaper to gently sand the target surface to remove the oxide layer and loose particles. The sanding process should be even and do not use excessive force to avoid damaging the substrate. After sanding, purge the surface with compressed air or argon to ensure that no residual particles are left.

[0051] Laser cladding equipment can choose fiber laser or carbon dioxide laser, and the power range can be set to 1kw-2kw. The scanning speed of laser cladding equipment can be set to 5-20mm / s. The spot diameter can be set to 1.5-2mm.

[0052] In the powder feeding device, the particle size of the molybdenum-tungsten alloy powder is 25-35 microns to ensure good fluidity and cladding effect. Its purity should be greater than 99.9%. Its rate can be set to 5-20 g / min. The powder feeding speed should match the laser power and scanning speed to ensure that the molybdenum-tungsten alloy powder is fully melted and evenly distributed in the cladding layer; the protective gas usually chooses argon, which is mixed in the molybdenum-tungsten alloy powder to provide protection to prevent the molybdenum-tungsten alloy powder from oxidizing during the cladding process. Its flow rate can be set to 10-20 L / min.

[0053] Step S2, performing laser cladding in a progressive layer-by-layer manner based on a preset cross-scanning path.

[0054] Laser cladding is specifically to form a molten pool on the surface of the target material through a high-energy laser beam, and at the same time, the molybdenum-tungsten alloy powder is fed into the molten pool through a powder feeding device to melt it and combine with the target material to form a dense coating to achieve the purpose of repairing the target material.

[0055] In some embodiments, the cross scan path includes at least a first path (corresponding to Figure 2 The dashed path in the figure) and the second path (corresponding to Figure 2 The first path and the second path present a cross-path structure. The specific structure is shown in the following formula:

[0056] ,

[0057] in, is the width of the path, is the spot diameter of the laser cladding equipment, is the scanning rate, is a correction factor, which depends on the cladding process parameters, such as the power of the laser cladding equipment, the material properties of the metal target, etc. That is to say, while ensuring that the cross-scanning path can cover the entire area to be repaired, it should be ensured that there is an appropriate overlap between the cross-scanning paths, which is usually set to 50% of the spot diameter. is the overlap ratio of the cross scan paths.

[0058] In an embodiment of the present invention, The value is 2s / mm. The value is 0.5.

[0059] It should be understood that the cross scanning path is the scanning path of the laser cladding equipment, which should be able to cover the entire area to be repaired, and the path width inside any path in the cross scanning path (for example: the first path or the second path) should be greater than or equal to the preset threshold value, so as to achieve the cross effect. It is not difficult to infer from the above formula that the preset threshold value is The internal path width refers to the distance between adjacent curves in any path.

[0060] The first path and the second path are laser clad in a layer-by-layer progressive manner. More specifically, Figure 2 Observe the direction of the arrow. Figure 3 The schematic diagram of multi-layer cladding is shown, which can be: first path 11, second path 21, first path 12, second path 22 and first path 13, and so on until the area to be repaired is filled. It can be understood that Figure 3 and Figure 2 The A, B, C and D marked in the figure are used to distinguish the relative positions of the two.

[0061] Considering that the bottom of the area to be repaired may not be flat, in some embodiments, the cross scanning path preset in step S2 may be set based on steps S21 to S24.

[0062] Step S21, setting a preliminary scanning trajectory.

[0063] It can be understood that the preliminary scanning trajectory differs from the cross scanning path only in that the scanning rate and the width of the path are uncertain.

[0064] Step S22, determining a 3D model of the area to be repaired, and using it to calculate the depth of each location in the area to be repaired.

[0065] In some embodiments, a filling material can be used to determine a 3D model of the area to be repaired. More specifically, first clean the area to be repaired to ensure that there is no oil, dust, and other contaminants. Secondly, apply the filling material evenly to the area to be repaired to ensure that all recessed and uneven areas are filled, and allow it to fully solidify according to the characteristics of the filling material. The curing time depends on the filling material, generally ranging from a few hours to a day. After taking out the filling material, finally determine the 3D model of the area to be repaired based on the 3D scanner, and use it to calculate the depth of each point in the area to be repaired. Among them, the filling material can be selected from polymer materials, such as silicone or epoxy resin.

[0066] Step S23, based on the depth of each location in the area to be repaired, determining the scanning rate and the width of the path at each location in the area to be repaired.

[0067] Step S24, determining a preset cross scanning path based on the scanning rate and the width of the path at each location in the area to be repaired.

[0068] In step S23, the scanning rate of each location in the area to be repaired is It can be shown as follows:

[0069] ,

[0070] in, is the two-dimensional position of the area to be repaired, In the area to be repaired The depth of the location and the area to be repaired The depth at the location, express The average depth at the location, is the laser power, is a fixed constant, which depends on the specific heat capacity and material density of the molybdenum-tungsten alloy target. In the embodiment of the present invention, The value is 2 .

[0071] In the above paragraph, a more specific approach may be: substitute the 3D model in step S22 into MATLAB, and MATLAB can obtain any position in the area to be repaired Next, MATLAB can perform a "rough" path planning based on the shape of the area to be repaired. If the area to be repaired is a rectangle, then the following can be used: Figure 2 In the manner shown, the first path and the second path are determined respectively in an alternating spiral manner; if the area to be repaired is elliptical, the first path and the second path can also be determined respectively in an alternating spiral manner.

[0072] The “rough” path planning area can be Figure 6 This section combines Figure 6 The following is a detailed description of how to obtain the scanning rate, path width, and cross-scan path based on the "rough" path planning area. First, determine multiple tracks in the rough range (for example: Figure 6 Then, according to equations (1), (2) and (3), a path point is selected from each track ( Figure 6 Finally, straight lines connect these path points to form a cross-scan path (for example: Figure 6 L1 and L2 in ).

[0073] The track should be perpendicular to the outline of the approximate area, and the width of the approximate area, that is, the length of the track, should be greater than or equal to the spot diameter of the laser cladding equipment. It is understandable that the wider the width, the more complex the calculation and the longer it takes. The selection of tracks should be as dense as possible. It is understandable that the denser the selection of tracks, the smoother the final cross-scanning path.

[0074] According to equations (1), (2) and (3), a path point is selected from each track, specifically including: firstly, calculating each point in each track The actual path width (the distance to the nearest cross path or the distance to the outer contour of the area to be repaired); then substitute into equation (2) and equation (3) to calculate its scanning rate However, since the scanning rate slows down, the width of the path will increase. Therefore, it is necessary to substitute the scanning rate into formula (1) again to recalculate a new path width. It is understandable that in the entire orbit, there must be a point that satisfies , and regard the point as a path point. For MATLAB software, it is only necessary to draw the function curve of the actual path width of each point and the function curve of the calculated new path width, and then take the intersection of the two as the path point. It should be noted that in order to simplify the description, when selecting each point in each track (for example: Figure 6 When the point G in the The direction of has been assumed to be the tangent direction of the current cross scan path. Correspondingly, the ordinate direction is ,like Figure 6 shown.

[0075] In fact, the area to be repaired can basically be regarded as an area with uniform and symmetrical depth gradient distribution. That is to say, assuming that the area to be repaired is a rectangle or ellipse, the equipotential lines inside the area to be repaired should also be approximately rectangular or elliptical. It can be understood that equipotential lines are lines with equal depth.

[0076] In some embodiments, step S23 may specifically include steps S231 to S233.

[0077] Step S231, determining a plurality of equipotential lines in the area to be repaired based on the depth of each location in the area to be repaired.

[0078] It can be understood that the distance between two adjacent equipotential lines is much smaller than the spot diameter of the laser cladding equipment, and is usually at least smaller than one tenth of the spot diameter of the laser cladding equipment.

[0079] Step S232: Calculate the average depth of each location in each area to be repaired based on the equipotential lines.

[0080] Step S233, based on the average depth of each location in the area to be repaired, determine the scanning rate and the width of the path at each location in the area to be repaired.

[0081] Understandably, in each area to be repaired Average depth at location As shown below:

[0082] ,

[0083] in, Indicates The depth of the equipotential lines, express With The vertical distance between the equipotential lines.

[0084] It should be understood that although the laser cladding equipment first scans the first path and then scans the second path; however, in step S23 and step S24, the order of determining the cross scanning paths can only be from the outside to the inside. Figure 3 As an illustration, in step S23 and step S24, the order of determining the cross-scanning paths should be: the second path 21 at D, the first path 11 at D, the second path 21 at C, the first path 11 at C, the second path 21 at B, the first path 11 at B, the second path 21 at A, the first path 11 at A, the second path 22 at D, and so on. Since the area to be repaired is usually a uniform and symmetrical figure, the use of equipotential lines can greatly reduce the calculation process and does not need to be substituted into MATLAB, but the result may not be accurate. That is to say, in step S233, it is only necessary to replace (4) Considered Substitute them into equation (2) and equation (1) respectively, and then obtain the scanning rate and the path width respectively. Correspondingly, the cross scanning path may include a first path, a second path, a third path and a fourth path, for example, they may be Figure 5 It should be understood that when the laser cladding equipment is scanning, it still follows the Figure 3 The logic shown is scanned, that is, the order is: C1, C3, C2, C4, C1, C3, C2, C4, etc. cross scanning.

[0085] Step S3, grinding the surface of the cladding layer after cooling, thereby completing the repair of the metal target.

[0086] Specifically, after laser cladding is completed, the area to be repaired is allowed to cool to room temperature, and the surface of the cladding layer is processed with fine sandpaper or polishing tools to ensure that the surface is smooth and free of defects. Furthermore, mechanical polishing or chemical polishing can be used to further improve the surface quality.

[0087] Correspondingly, the present invention also discloses a metal target repair system, comprising: laser cladding equipment, molybdenum-tungsten alloy powder, a powder feeding device and a cleaning and polishing tool.

[0088] After the laser cladding equipment is initialized, it is used to perform laser cladding in a progressive layer-by-layer manner based on a preset cross-scanning path;

[0089] Molybdenum-tungsten alloy powder is placed inside the powder feeding device. During laser cladding, the powder feeding device feeds the molybdenum-tungsten alloy powder into the molten pool to melt it and combine it with the target material to form a dense coating to repair the target material.

[0090] The cleaning and grinding tools are used to clean and grind the metal target, and grind the surface of the cladding layer after cooling, thereby completing the repair of the metal target.

[0091] In order to illustrate the technical effect of the present invention, the present invention selects a simple case where the area to be repaired is a square for verification. Figure 2 As shown. The laser cladding equipment is selected as a fiber laser, the power range is 2kw, the scanning speed is 10mm / s, and the spot diameter is set to 2mm. In the powder feeding device, the particle size of the molybdenum-tungsten alloy powder is set to 25 microns and the rate is 10g / min. In the cross scanning path, the first path and the second path can be as follows Figure 2 As shown, when Take 2, When 0.5 is taken, the width of the path is calculated as 0.2 mm according to formula (1), and the scanning rate can be further calculated according to formula (2) and formula (3). After the scanning is completed, the Raman spectrometer is used to select the six repaired areas for testing. The results are as follows: Figure 7 shown. Figure 7 The results show that the laser cladding technology of the present invention forms a uniform Raman spectrum in 6 areas: the tungsten content ranges from 4.92%, 4.93%, 4.97%, 5.04%, 5.07% and 5.12% in the different areas selected for testing. This shows that the composition and structure of the repair layer are uniform. In addition, the half-height width of the Raman peak is small, indicating that the chemical bond state of the repair layer is good, with fewer defects and stress.

[0092] For comparison, the present invention also adopts a spiral scanning cladding method for the prior art, such as Figure 4As shown in the figure, while ensuring that all parameters remain unchanged, after the scanning is completed, the Raman spectrometer is also used to select the 6 repaired areas for testing. The results are as follows Figure 8 shown. Figure 8 The results show that the Raman spectra of different areas of the spiral scanning cladding method have obvious differences: the tungsten content ranges from 1.3%, 2.3%, 3.6%, 4.8%, 5.3%, and 7.6% in the different areas selected for the test. This indicates that the uniformity of the repair layer is poor. In addition, Figure 8 The half-width of the middle Raman peak is large, indicating that there are more chemical bond state changes and stress concentration in the repair layer, which may lead to a decrease in the mechanical strength and durability of the material.

[0093] The parameters of the Raman spectrometer are as follows: excitation wavelength: 532nm; laser power: 10mW; spot diameter: 1um; integration time: 10s; spectral range: 200-1300cm -1 .

[0094] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0095] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for repairing a metal target material, used for repairing a molybdenum-tungsten alloy target material, characterized in that: The method comprises steps S1 to S3; Step S1, cleaning and grinding of the metal target, and initialization of the laser cladding equipment and the powder feeding device; Step S2, performing laser cladding in a progressive layer-by-layer manner based on a preset cross scanning path; The cross scanning path is the scanning path of the laser cladding equipment, covering the entire area to be repaired, including the first path and the second path. The first path and the second path present a cross path structure. The width of the path is shown in the following formula: ； in, is the width of the path, is the spot diameter of the laser cladding equipment, is the correction factor, is the scanning rate, is the overlap ratio of the cross-scan paths; Step S3, grinding the surface of the cladding layer after cooling, thus completing the repair of the metal target; The cross scanning path preset in step S2 is set based on steps S21 to S24; Step S21, setting a preliminary scanning trajectory; Step S22, determining a 3D model of the area to be repaired, and using it to calculate the depth of each location in the area to be repaired; Step S23, determining the scanning rate and the width of the path at each location in the area to be repaired based on the depth of each location in the area to be repaired; Step S24, determining a preset cross scanning path based on the scanning rate and the width of the path at each location in the area to be repaired; Scan rate at each location in the area to be repaired As shown below: ； ； in, is the two-dimensional position of the area to be repaired, In the area to be repaired The depth of the location and the area to be repaired The depth at the location, is the laser power, express The average depth at the location, is a fixed constant; Step S23 specifically includes steps S231 to S233; Step S231, determining a plurality of equipotential lines in the area to be repaired based on the depth of each location in the area to be repaired; Step S232, based on the equipotential lines, calculating the average depth of each location in each area to be repaired; Step S233, determining the scanning rate and the width of the path at each location in the area to be repaired based on the average depth of each location in the area to be repaired; In each area to be repaired Average depth at location As shown below: ； in, Indicates The depth of the equipotential lines, express With The vertical distance between the equipotential lines.

2. A method for repairing a metal target according to claim 1, characterized in that: Step S1 specifically includes: using an organic solvent to clean the surface of the molybdenum-tungsten alloy target to remove grease, dust and other contaminants; using fine sandpaper to polish the surface of the target to remove the oxide layer and loose particles; the laser cladding equipment is set to a fiber laser or a carbon dioxide laser, the power range is set to 1kw-2kw, the scanning speed is set to 5-20mm / s, and the spot diameter is set to 1.5-2mm; the particle size of the molybdenum-tungsten alloy powder is 25-35 microns, the purity is greater than 99.9%, and the rate is set to 5-20 g / min; the protective gas is selected as argon, which is mixed in the molybdenum-tungsten alloy powder to prevent the molybdenum-tungsten alloy powder from oxidizing during the cladding process, and its flow rate is set to 10-20 L / min.

3. A method for repairing a metal target according to claim 1, characterized in that: Laser cladding is specifically to form a molten pool on the surface of the target material through a high-energy laser beam, and at the same time, the molybdenum-tungsten alloy powder is fed into the molten pool through a powder feeding device to melt it and combine with the target material to form a dense coating to achieve the purpose of repairing the target material.

4. A method for repairing a metal target according to claim 1, characterized in that: Step S22 specifically includes: first, cleaning the area to be repaired to ensure that there is no oil, dust and other pollutants; second, applying the filling material evenly to the area to be repaired to ensure that all recessed and uneven areas are filled, and allowing the filling material to fully solidify according to its characteristics. After removing the filling material, finally determine the 3D model of the area to be repaired based on the 3D scanner, and use it to calculate the depth of each point in the area to be repaired.

Images