A titanium-aluminum metal rotating target and its preparation method

Abstract

This invention discloses a titanium-aluminum metal rotating target and its preparation method, belonging to the field of target material technology. The preparation method includes the following steps: preparing a pure silver coating on the surface of a stainless steel backing tube using conventional cold spraying; depositing a titanium-aluminum deposition layer on the pure silver coating surface using vacuum cold spraying, and simultaneously subjecting the deposition layer to laser shock peening using a laser shock intensification process; repeating the above steps until the total thickness of the titanium-aluminum deposition layer reaches a preset thickness. This method is simple to operate, has high material utilization, and is not limited by target size, enabling the preparation of large rotating targets. The prepared target has high density, small grains, uniform structure, low gas content, and high bonding strength with the backing tube. The pure silver coating further enhances the conductivity and sputtering uniformity of the target.

Description

Technical Field

[0001] This invention relates to the field of target technology, and more specifically, to a titanium-aluminum metal rotating target and its preparation method. Background Technology

[0002] Titanium-aluminum targets are widely used in the preparation of reinforcing films for drill bits and cutting tools, which can effectively extend the service life of related components. However, the preparation of large-size, high-density titanium-aluminum alloy targets is difficult. According to the titanium-aluminum alloy phase diagram, titanium and aluminum can form various intermetallic compounds, resulting in the brittleness of titanium-aluminum alloys during processing. The processing of titanium-aluminum alloy targets is difficult, and the finished titanium-aluminum alloy targets are brittle and may fracture under pressure conditions, causing potential service risks. At the same time, the exothermic expansion during the alloying process of titanium and aluminum can easily generate bubbles and shrinkage cavities, which cannot meet the requirements for the preparation of high-density titanium-aluminum targets.

[0003] To improve sputtering efficiency and reduce costs, sputtering targets are being developed towards larger sizes, which also places higher demands on the grain size control of sputtering targets. However, conventional processes such as high current heating, hot isostatic pressing, and hot pressing sintering have the drawback of making it difficult to develop large-scale equipment for the preparation of large-size rotating tubular titanium-aluminum targets.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a titanium-aluminum metal rotating target and its preparation method, so as to solve or improve the above-mentioned technical problems.

[0006] This application can be implemented as follows:

[0007] In a first aspect, this application provides a method for preparing a titanium-aluminum metal rotating target, which includes the following steps:

[0008] S1: A pure silver coating is prepared on the surface of a stainless steel back tube using a conventional cold spraying method;

[0009] S2: A titanium-aluminum deposition layer is deposited on the surface of a pure silver coating using a vacuum cold spraying method. Simultaneously, the deposition layer is subjected to laser shock blasting using a laser shock strengthening process.

[0010] S3: Repeat S2 continuously until the total thickness of the titanium-aluminum deposited layer reaches the preset thickness.

[0011] In an optional implementation, prior to S1, the method further includes: performing controlled corrosion matrix roughening on the surface of the stainless steel back tube.

[0012] In an optional implementation, the diameter of the matrix micro-pits corresponding to the controllable corrosion matrix coarsening is 5 μm and the depth is 5-8 μm.

[0013] In an optional embodiment, in S1, the silver powder used to prepare the pure silver coating is micron-sized silver powder.

[0014] In an optional embodiment, the silver powder has a particle size of 1-5 μm.

[0015] In an optional implementation, the purity of the silver powder is not less than 99.99%.

[0016] In an optional implementation, in S1, conventional cold spraying includes at least one of the following features:

[0017] Feature 1: The working gas is nitrogen;

[0018] Feature 2: Spraying pressure is 3-6 MPa;

[0019] Feature 3: Spraying temperature is 800-1000℃;

[0020] Feature 4: Spraying distance is 30mm.

[0021] In an optional embodiment, before S2, the method further includes: laser cleaning of the oxide film on the surface of the pure silver coating.

[0022] In an optional embodiment, in S2, the titanium source and aluminum source for preparing the titanium-aluminum deposition layer are elemental titanium powder and elemental aluminum powder, respectively.

[0023] In an optional embodiment, the particle size of the titanium powder is 0.1-30 μm, and the particle size of the aluminum powder is 5-45 μm.

[0024] In an optional embodiment, the purity of the titanium powder is not less than 99.99%, and the purity of the aluminum powder is not less than 99.99%.

[0025] In an optional embodiment, the mass of elemental titanium powder accounts for 1-50% of the total mass of elemental titanium powder and elemental aluminum powder.

[0026] In an optional embodiment, in S2, vacuum cold spraying includes at least one of the following features:

[0027] Feature 1: The working gas is helium;

[0028] Feature 2: Spraying pressure is 2.5-3.5 MPa;

[0029] Feature 3: Spraying temperature is 400-600℃;

[0030] Feature 4: Spraying distance is 30mm;

[0031] Feature 5: Vacuum degree during spraying <1Kpa.

[0032] In an optional implementation, in S2, the laser shock peening process includes at least one of the following features:

[0033] Feature 1: The diameter of the light spot is 4-10mm;

[0034] Feature 2: The overlap rate of light spots is 1-25%;

[0035] Feature 3: Peak pressure is 1.5-4 GPa.

[0036] In an optional implementation, S3 is followed by:

[0037] S4: Deposit an additional 5-10mm of titanium-aluminum deposit at both ends of the stainless steel back tube.

[0038] Secondly, this application provides a titanium-aluminum metal rotating target, which is prepared by any of the preparation methods described in the foregoing embodiments.

[0039] In an optional embodiment, the titanium-aluminum metal rotating target includes at least one of the following features:

[0040] Feature 1: The titanium-aluminum metal rotating target is dumbbell-shaped;

[0041] Feature 2: The thickness of the pure silver coating is <5μm;

[0042] Feature 3: The total thickness of the titanium-aluminum deposited layer is 5-30 mm;

[0043] Feature 4: The thickness of a single layer of titanium-aluminum deposition layer is <1mm.

[0044] The beneficial effects of this application include:

[0045] The titanium-aluminum metal rotating target provided in this application is formed by first depositing a pure silver coating on the back tube surface using cold spraying technology, then depositing titanium and aluminum elemental powders onto the pure silver coating using vacuum cold spraying technology, and simultaneously performing laser shock strengthening process on the titanium-aluminum deposition layer during the deposition of the titanium-aluminum deposition layer. Through repeated deposition and shock strengthening, a large-size rotating titanium-aluminum metal target is formed layer by layer.

[0046] The above method effectively improves material utilization, prevents oxidation and decomposition, and allows the target material to retain its original components intact. The resulting rotating target material is dense, has small grains, uniform structure, low gas content, and high interfacial bonding strength, which significantly improves the target material's performance, while also allowing for unrestricted target size. Furthermore, the presence of a pure silver coating in the target material enhances conductivity and ensures more uniform sputtering. Attached Figure Description

[0047] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a schematic diagram illustrating the fabrication of the titanium-aluminum metal rotating target provided in this application;

[0049] Figure 2 A schematic diagram illustrating the laser shock peening principle during the fabrication of the titanium-aluminum metal rotating target provided in this application;

[0050] Figure 3 This is a cross-sectional view of the surface of the stainless steel back tube after step S1 in Embodiment 1 of this application;

[0051] Figure 4 This is a microstructure diagram of the titanium-aluminum deposited layer in Example 1 of this application, where the dark color represents titanium and the light color represents aluminum;

[0052] Figure 5 This is a schematic diagram of the structure of the dumbbell-shaped titanium-aluminum metal rotating target obtained in Example 1 of this application;

[0053] Figure 6 This is a physical image of the dumbbell-shaped titanium-aluminum metal rotating target prepared in Example 1 of this application. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0055] The titanium-aluminum metal rotating target and its preparation method provided in this application are described in detail below.

[0056] This application proposes a method for preparing a titanium-aluminum metal rotating target, the preparation schematic diagram of which is shown below. Figure 1 As shown, the process includes the following steps:

[0057] S1: A pure silver coating is prepared on the surface of a stainless steel back tube using a conventional cold spraying method;

[0058] S2: A titanium-aluminum deposition layer is deposited on the surface of a pure silver coating using a vacuum cold spraying method. Simultaneously, the deposition layer is subjected to laser shock blasting using a laser shock strengthening process.

[0059] S3: Repeat S2 continuously until the total thickness of the titanium-aluminum deposited layer reaches the preset thickness.

[0060] In the above preparation process, the stainless steel back tube is placed on a turntable and rotated at a speed of 200-400 rpm.

[0061] For reference, prior to S1, it also includes: controlled corrosion matrix roughening of the surface of the stainless steel back tube.

[0062] In some implementations, controlled corrosion matrix roughening can be achieved through steps such as grinding, coating, developing, and etching. By performing the above pretreatment on the surface of the stainless steel back tube, a matrix of micropits can be formed on the surface of the stainless steel back tube, which helps to increase the contact area between the pure silver coating and the substrate (stainless steel back tube) and improve the interfacial bonding strength.

[0063] The aforementioned pretreatment methods, such as polishing, coating, developing, and etching, can be referred to relevant existing technologies and will not be elaborated on here.

[0064] It should be noted that in other embodiments, the form of the micro-pits is not limited to a matrix, and can be set to any other shape and arrangement as needed.

[0065] For example, the diameter of the matrix micropits corresponding to the controllable corrosion matrix coarsening can be 5 μm and the depth can be 5-8 μm (such as 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm or 8 μm, etc.).

[0066] In this application, in S1, the silver powder used to prepare the pure silver coating is micron-sized silver powder.

[0067] For reference, the particle size of silver powder can be 1-5 μm, such as 1 μm, 2 μm, 3 μm, 4 μm, or 5 μm. The purity of the silver powder is not less than 99.99%.

[0068] If the particle size of the silver powder is less than 1μm, it is not conducive to stable powder output during spraying; if the particle size of the silver powder is greater than 5μm, it is not conducive to the preparation of thin silver coatings and the cost is high.

[0069] By placing a pure silver coating between the substrate and the titanium-aluminum deposition layer, the target material can be made more conductive and sputtered more uniformly.

[0070] For reference, in S1, the working gas for conventional cold spraying is nitrogen.

[0071] The spraying pressure is 3-6MPa, such as 3MPa, 3.5MPa, 4MPa, 4.5MPa, 5MPa, 5.5MPa or 6MPa, or any other value within the range of 3-6MPa.

[0072] If the spraying pressure is less than 3 MPa, it is not conducive to the preparation of a high-quality deposited layer; if the spraying pressure is greater than 6 MPa, it is easy to clog the spray gun and the gas cost is high.

[0073] The spraying temperature can be 800-1000℃, such as 800℃, 850℃, 900℃, 950℃ or 1000℃, or any other value within the range of 800-1000℃.

[0074] If the spraying temperature is below 800℃, it is not conducive to the preparation of a high-quality deposited layer; if the spraying temperature is above 1000℃, it is not conducive to stable spraying and the nozzle is prone to clogging.

[0075] The spraying distance is 30mm.

[0076] In some preferred embodiments, prior to step S2, laser cleaning of the oxide film on the surface of the pure silver coating is performed. Laser cleaning using a laser cleaning agent removes the oxide film from the surface of the pure silver coating.

[0077] For reference, in S2, the titanium source and aluminum source for preparing the titanium-aluminum deposition layer are elemental titanium powder and elemental aluminum powder, respectively.

[0078] The particle size of the titanium elemental powder can be 0.1-30μm, such as 0.1μm, 0.5μm, 1μm, 2μm, 5μm, 10μm, 15μm, 20μm, 25μm or 30μm, or any other value within the range of 0.1-30μm.

[0079] If the particle size of titanium powder is less than 0.1 μm, it is not conducive to titanium powder deposition; if the particle size of titanium powder is greater than 30 μm, it is not conducive to the preparation of uniform target material.

[0080] The particle size of aluminum elemental powder can be 5-45μm, such as 5μm, 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm or 45μm, or any other value within the range of 5-45μm.

[0081] If the particle size of the aluminum powder is less than 5 μm, it is not conducive to uniform powder feeding; if the particle size of the aluminum powder is greater than 45 μm, it is not conducive to the preparation of high-quality coatings.

[0082] The purity of the above-mentioned titanium powder and aluminum powder is preferably not less than 99.99%.

[0083] The mass of titanium powder can account for 1-50% of the total amount of titanium powder and aluminum powder, such as 1%, 2%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45% or 50%, or any other value within the range of 1-50%.

[0084] Before use, simply mechanically mix the titanium powder and aluminum powder according to the preset ratio until they are evenly combined.

[0085] In S2, the titanium-aluminum deposition layer is prepared by vacuum cold spraying, which can alleviate the oxidation phenomenon of titanium-aluminum materials during deposition.

[0086] The working gas for vacuum cold spraying is helium, and the helium circulation system helps to reduce costs.

[0087] The spraying pressure can be 2.5-3.5MPa, such as 2.5MPa, 2.8MPa, 3MPa, 3.2MPa or 3.5MPa, or any other value within the range of 2.5-3.5MPa.

[0088] If the spraying pressure is less than 2.5 MPa, it is not conducive to the preparation of high-quality deposits; if the spraying pressure is higher than 3.5 MPa, the cost will increase.

[0089] The spraying temperature can be 400-600℃, such as 400℃, 450℃, 500℃, 550℃ or 600℃, or any other value within the range of 400-600℃.

[0090] If the spraying temperature is below 400℃, it is not conducive to the preparation of high-quality deposits; if the spraying temperature is above 600℃, it is easy to clog the spray gun.

[0091] During spraying, the vacuum level should be controlled to be less than 1 kPa. If it is greater than 1 kPa, non-bonding defects are likely to appear at the particle interface of the deposit.

[0092] The spraying distance can be 30mm.

[0093] In S2, the laser spot diameter of the laser shock peening process can be 4-10mm, such as 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm, or any other value within the range of 4-10mm.

[0094] If the diameter of the light spot is less than 4 mm, it cannot cover the powder spots; if the diameter of the light spot is greater than 4 mm, the introduced energy is too high, which can easily lead to cracking of the deposit.

[0095] The laser spot overlap rate of the laser shock strengthening process can be 1-25%, such as 1%, 2%, 5%, 8%, 10%, 15%, 20% or 25%, or any other value within the range of 1-25%.

[0096] If the overlap rate of the light spot is less than 1%, it is easy to miss the impact area; if the overlap rate is greater than 25%, the impact efficiency is low.

[0097] The peak pressure of the laser shock peening process can be 1.5-4 GPa, such as 1.5 GPa, 2 GPa, 2.5 GPa, 3 GPa, 3.5 GPa or 4 GPa, or any other value within the range of 1.5-4 GPa.

[0098] If the peak pressure is less than 1.5 GPa, the efficiency is low; if the peak pressure is greater than 4 GPa, the energy is too high, which can easily lead to cracking of the sediment.

[0099] By performing laser shock (e.g.) simultaneously with the deposition of titanium-aluminum deposits Figure 2 As shown, this method can eliminate microscopic defects in titanium-aluminum deposits and further refine the grain size of the deposits.

[0100] In this application, step S3 can be understood as repeatedly depositing titanium-aluminum metal layers and laser shocking on the surface of the titanium-aluminum deposited layer after laser shock in step S2, thereby forming a titanium-aluminum deposited layer of a preset thickness layer by layer.

[0101] Furthermore, this application includes an S4 step after S3, which involves depositing an additional 5-10 mm of titanium-aluminum deposition layer at both ends of the stainless steel back tube. After this, the target material can be machined into a dumbbell shape.

[0102] The positions at both ends of the aforementioned stainless steel back tube can be understood as sputtering consumable areas. The length of each end of the stainless steel back tube corresponding to these sputtering consumable areas is approximately 10-30 cm. By depositing a certain thickness of titanium-aluminum deposition layer in these consumable areas, it is beneficial to improve the service life of the target material.

[0103] As mentioned above, the preparation method of titanium-aluminum metal rotating target provided in this application can effectively improve the material utilization rate. Based on the cold spraying technology, titanium-aluminum metal target material can be formed by using titanium-aluminum elemental materials in proportion. The target material size is not limited and large rotating targets can be prepared, such as target material size up to 4m. This can significantly improve the utilization efficiency of the target material while reducing raw material costs.

[0104] It should be noted that the devices involved in the traditional cold spraying process, vacuum cold spraying process and laser shock peening process in this application can refer to the relevant existing technologies, and will not be limited or elaborated here.

[0105] Accordingly, this application also provides a titanium-aluminum metal rotating target, which is prepared by the above-described preparation method.

[0106] For reference, the titanium-aluminum metal rotating target is dumbbell-shaped.

[0107] In this titanium-aluminum metal rotating target, the thickness of the pure silver coating can be <5μm, such as 4.8μm, 4.5μm, 4μm, 3.5μm, 3μm, 2.5μm, 2μm, 1.5μm, 1μm or 0.5μm, or other thicknesses within the range of <5μm.

[0108] It should be noted that if the thickness of the pure silver coating exceeds 5μm, it will not be conducive to cost savings.

[0109] In this titanium-aluminum metal rotating target, the total thickness of the titanium-aluminum deposited layer can be 5-30mm, such as 5mm, 8mm, 10mm, 15mm, 20mm, 25mm or 30mm, or other thicknesses within the range of 5-30mm.

[0110] The thickness of a single titanium-aluminum deposit is <1mm, such as 0.8mm, 0.6mm, 0.5mm, 0.4mm, 0.2mm or 0.1mm.

[0111] It should be noted that by controlling the thickness of a single layer of titanium-aluminum deposition to <1mm, laser shock peening technology can be used to laser shock the titanium-aluminum deposition layer, thereby eliminating microscopic defects in the titanium-aluminum deposition body and further refining the grains of the titanium-aluminum deposition body.

[0112] Furthermore, the titanium-aluminum metal rotating target prepared by the method provided in this application has high density, small grains, uniform structure, low gas content, and high bonding strength with the back tube.

[0113] The resulting titanium-aluminum metal rotating target can be applied in the fields of wear-resistant and wear-reducing equipment such as drill bits and cutting tools.

[0114] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0115] Example 1

[0116] This embodiment provides a titanium-aluminum metal rotating target, the preparation method of which includes the following steps:

[0117] S0: Grinding, applying adhesive, developing, and etching are performed on the surface of a 304 stainless steel back tube with a length of 3000 mm and a diameter of 132.5 mm to form a matrix of micro-pits with a diameter of approximately 5 μm and a depth of approximately 6 μm (e.g., ...). Figure 3 (As shown).

[0118] S1: A 4-micron-thick pure silver coating is deposited on the surface of a stainless steel back tube using cold spraying technology. In this process, the cold spraying gas source is high-purity (99.999%) nitrogen, the spraying pressure is 4 MPa, the temperature is 1000℃, and the spraying distance is 30 mm. The silver powder used for spraying has a particle size of 1-5 μm (average particle size 4 μm) and a purity of 99.99%.

[0119] After the coating is applied, a laser cleaning machine is used to remove the oxide film from the surface of the pure silver coating.

[0120] S2: The pure silver-coated base tube is placed in the vacuum spraying chamber. Vacuum cold spraying technology is used to deposit the mixed titanium and aluminum powders onto the base tube, with a single layer thickness of 0.8 mm. Simultaneously, laser shock peening is used to densify the titanium-aluminum deposit, layer by layer, until a thickness of 12 mm is achieved (see reference). Figure 4 ).

[0121] The purity of both titanium and aluminum powder used in the above-mentioned vacuum cold spraying is 99.9%. The particle size of titanium powder is 0.1-1.2μm (average particle size is 0.8μm), and the particle size of aluminum powder is 5-45μm (average particle size is 28μm). The titanium and aluminum powders are mechanically stirred and mixed for 30 minutes before spraying. The mass of titanium powder accounts for 45wt% of the total amount of titanium and aluminum powder.

[0122] The working gas used in the above-mentioned vacuum cold spraying is helium, the spraying pressure is 3MPa, the spraying temperature is 500℃, the spraying distance is 30mm, and the vacuum degree is controlled at <1Kpa.

[0123] The process conditions corresponding to the above laser shock peening process are as follows: the spot diameter is 5 mm, the spot overlap rate is 5%, and the peak pressure is 2 GPa.

[0124] S4: When the target blank thickness reaches 12mm through repeated layer-by-layer deposition, continue sputtering at the consumable areas 30cm from both ends of the target blank to prepare a 10mm thick titanium-aluminum composite deposition layer. Finally, machine the product to form a dumbbell-shaped target material (e.g., Figure 5 and Figure 6 (As shown).

[0125] During processes S1 to S4, the turntable holding the stainless steel back tube rotates at a speed of 300 rpm.

[0126] Example 2

[0127] This embodiment provides a titanium-aluminum metal rotating target, the preparation method of which includes the following steps:

[0128] S0: Grinding, applying adhesive, developing and etching are performed on the surface of a 304 stainless steel back tube with a length of 3000mm and a diameter of 132.5mm to form a matrix of micro-pits with a diameter of about 5μm and a depth of about 8μm on the surface of the stainless steel back tube.

[0129] S1: A 3μm thick pure silver coating is deposited on the surface of a stainless steel back tube using cold spraying technology. In this process, the cold spraying gas source is industrial high-purity nitrogen, the spraying pressure is 6MPa, the temperature is 1000℃, and the spraying distance is 30mm. The silver powder used for spraying has a particle size of 1-5μm (average particle size 4μm) and a purity of 99.99%.

[0130] After the coating is applied, a laser cleaning machine is used to remove the oxide film from the surface of the pure silver coating.

[0131] S2: Place the pure silver-coated base tube into the vacuum spraying chamber, and use vacuum cold spraying technology to deposit the mixed titanium and aluminum elemental powders onto the base tube with a single layer thickness of 0.8mm. At the same time, use laser shock strengthening process to densify the titanium-aluminum deposition layer, and deposit it layer by layer until it reaches 10mm.

[0132] The purity of both titanium and aluminum powder used in the above-mentioned vacuum cold spraying is 99.9%. The particle size of titanium powder is 0.1-1.2μm (average particle size is 0.8μm), and the particle size of aluminum powder is 5-45μm (average particle size is 25μm). The titanium and aluminum powders are mechanically stirred and mixed for 30 minutes before spraying. The mass of titanium powder accounts for 40wt% of the total mass of titanium and aluminum powders.

[0133] The working gas used in the above-mentioned vacuum cold spraying is helium, the spraying pressure is 3MPa, the spraying temperature is 500℃, and the spraying distance is 30mm.

[0134] The process conditions corresponding to the above laser shock peening process are as follows: the spot diameter is 5 mm, the spot overlap rate is 5%, and the peak pressure is 2 GPa.

[0135] S4: When the target blank thickness reaches 10mm through repeated layer-by-layer deposition, continue to sputter the consumable area 20cm at both ends of the target blank to prepare a titanium-aluminum composite deposition layer with a thickness of 5mm. Finally, the dumbbell-shaped target material is formed by machining.

[0136] During processes S1 to S4, the turntable holding the stainless steel back tube rotates at a speed of 300 rpm.

[0137] Example 3

[0138] This embodiment provides a titanium-aluminum metal rotating target, the preparation method of which includes the following steps:

[0139] S0: Grinding, applying adhesive, developing and etching are performed on the surface of a 304 stainless steel back tube with a length of 3000mm and a diameter of 132.5mm to form a matrix of micro-pits with a diameter of about 5μm and a depth of about 5μm on the surface of the stainless steel back tube.

[0140] S1: A 1μm thick pure silver coating is deposited on the surface of a stainless steel back tube using cold spraying technology. In this process, the cold spraying gas source is industrial high-purity nitrogen, the spraying pressure is 3MPa, the temperature is 800℃, and the spraying distance is 30mm. The silver powder used for spraying has a particle size of 1-5μm (average particle size 3μm) and a purity of 99.99%.

[0141] After the coating is applied, a laser cleaning machine is used to remove the oxide film from the surface of the pure silver coating.

[0142] S2: Place the pure silver-coated base tube into the vacuum spraying chamber, and use vacuum cold spraying technology to deposit the mixed titanium and aluminum elemental powders onto the base tube with a single layer thickness of 0.5mm. At the same time, use laser shock strengthening process to densify the titanium and aluminum deposition layer, and deposit it layer by layer until it reaches 5mm.

[0143] The purity of both titanium and aluminum powder used in the above-mentioned vacuum cold spraying is 99.9%. The particle size of titanium powder is 5-30 μm (average particle size is 10 μm), and the particle size of aluminum powder is 5-45 μm (average particle size is 25 μm). The titanium and aluminum powders are mechanically stirred and mixed for 30 min before spraying. The mass of titanium powder accounts for 40 wt% of the total amount of titanium and aluminum powder.

[0144] The working gas used in the above-mentioned vacuum cold spraying is helium, the spraying pressure is 2.5MPa, the spraying temperature is 400℃, and the spraying distance is 30mm.

[0145] The process conditions corresponding to the above laser shock peening process are as follows: the spot diameter is 4 mm, the spot overlap rate is 1%, and the peak pressure is 1.5 GPa.

[0146] S4: When the target blank thickness reaches 5mm through repeated layer-by-layer deposition, continue to sputter the consumable area 10cm at both ends of the target blank to prepare a titanium-aluminum composite deposition layer with a thickness of 10mm layer by layer. Finally, the dumbbell-shaped target material is formed by machining.

[0147] During processes S1 to S4, the turntable holding the stainless steel back tube rotates at a speed of 300 rpm.

[0148] Example 4

[0149] This embodiment provides a titanium-aluminum metal rotating target, the preparation method of which includes the following steps:

[0150] S0: Grinding, applying adhesive, developing and etching are performed on the surface of a 304 stainless steel back tube with a length of 3000mm and a diameter of 132.5mm to form a matrix of micro-pits with a diameter of about 5μm and a depth of about 7μm on the surface of the stainless steel back tube.

[0151] S1: A 4μm thick pure silver coating is deposited on the surface of a stainless steel back tube using cold spraying technology. In this process, the cold spraying gas source is conventional industrial high-purity nitrogen, the spraying pressure is 5MPa, the temperature is 900℃, and the spraying distance is 30mm. The silver powder used for spraying has a particle size of 1-5μm (average particle size 2μm) and a purity of 99.99%.

[0152] After the coating is applied, a laser cleaning machine is used to remove the oxide film from the surface of the pure silver coating.

[0153] S2: Place the pure silver-coated base tube into the vacuum spraying chamber, and use vacuum cold spraying technology to deposit the mixed titanium and aluminum elemental powders onto the base tube with a single layer thickness of 0.1mm. At the same time, use laser shock strengthening process to densify the titanium-aluminum deposition layer, and repeatedly deposit layer by layer until it reaches 30mm.

[0154] The purity of both titanium and aluminum powder used in the above-mentioned vacuum cold spraying is 99.9%. The particle size of titanium powder is 10-30 μm (average particle size is 20 μm), and the particle size of aluminum powder is 5-45 μm (average particle size is 30 μm). The titanium and aluminum powders are mechanically stirred and mixed for 30 min before spraying. The mass of titanium powder accounts for 40 wt% of the total amount of titanium and aluminum powder.

[0155] The working gas used in the above-mentioned vacuum cold spraying is helium, the spraying pressure is 3.5MPa, the spraying temperature is 600℃, and the spraying distance is 30mm.

[0156] The process conditions corresponding to the above laser shock peening process are as follows: the spot diameter is 10 mm, the spot overlap rate is 25%, and the peak pressure is 4 GPa.

[0157] S4: When the target blank thickness reaches 30mm through repeated deposition, continue to sputter the consumable area at 30cm at both ends of the target blank to prepare a titanium-aluminum composite deposition layer with a thickness of 8mm. Finally, the dumbbell-shaped target material is formed by machining.

[0158] During processes S1 to S4, the turntable holding the stainless steel back tube rotates at a speed of 300 rpm.

[0159] Comparative Example 1

[0160] The difference between this comparative example and Example 1 is that in S1, the surface of the stainless steel back tube is only subjected to conventional grinding and sandblasting roughening processes, and no matrix-like micro-pits are formed.

[0161] Comparative Example 2

[0162] The difference between this comparative example and Example 1 is that in S3, conventional cold spraying technology is used to deposit the mixed titanium and aluminum elemental powders onto the target back tube.

[0163] The spraying conditions involved in this process mainly include: a spraying pressure of 3MPa, a spraying temperature of 500℃, and a spraying distance of 30mm.

[0164] Comparative Example 3

[0165] The difference between this comparative example and Example 1 is that in S3, the laser shock strengthening process was not used to perform a laser shock process on the single-layer titanium-aluminum deposition layer.

[0166] Comparative Example 4

[0167] The difference between this comparative example and Example 1 is that in S3, the thickness of a single layer of titanium-aluminum deposition layer is 2 mm.

[0168] Comparative Example 5

[0169] The difference between this comparative example and Example 1 is that a thicker titanium-aluminum composite layer was not deposited in the consumable areas at both ends of the target blank, and the finished target material was not cylindrical or dumbbell-shaped; that is, step S4 was omitted.

[0170] Comparative Example 6

[0171] The difference between this comparative example and Example 1 is that the back tube surface was not coated with pure silver as a base; that is, there is no S1 step, and S2 is performed directly after S0.

[0172] Comparative Example 7

[0173] The difference between this comparative example and Example 1 is that in S1, the depth of the matrix-type micro-pits is 15 μm.

[0174] Comparative Example 8

[0175] The difference between this comparative example and Example 1 is that in S1, the depth of the matrix-type micro-pits is 2 μm.

[0176] Comparative Example 9

[0177] The difference between this comparative example and Example 1 is that in S2, the thickness of the pure silver coating is 10 μm.

[0178] Comparative Example 10

[0179] The difference between this comparative example and Example 1 is that in S2, the particle size of the silver powder is 0.5 μm.

[0180] Comparative Example 11

[0181] The difference between this comparative example and Example 1 is that in S2, the particle size of the silver powder is 10 μm.

[0182] Comparative Example 12

[0183] The difference between this comparative example and Example 1 is that in S2, the spraying pressure is 1 MPa.

[0184] Comparative Example 13

[0185] The difference between this comparative example and Example 1 is that in S2, the spraying pressure is 10 MPa.

[0186] Comparative Example 14

[0187] The difference between this comparative example and Example 1 is that in S2, the spraying temperature is 600°C.

[0188] Comparative Example 15

[0189] The difference between this comparative example and Example 1 is that in S2, the spraying temperature is 1200°C.

[0190] Comparative Example 16

[0191] The difference between this comparative example and Example 1 is that in S2, the spraying distance is 10mm.

[0192] Comparative Example 17

[0193] The difference between this comparative example and Example 1 is that in S2, the spraying distance is 100mm.

[0194] Comparative Example 18

[0195] The difference between this comparative example and Example 1 is that the oxide film on the surface of the pure silver coating was not laser-cleaned before S2.

[0196] Comparative Example 19

[0197] The difference between this comparative example and Example 1 is that in S3, the particle size of the titanium elemental powder is 50 μm.

[0198] Test case

[0199] The performance of the titanium-aluminum metal rotating targets obtained in Examples 1-4 and Comparative Examples 1-19 was compared, and the results are shown in Table 1. The test standard for bonding strength was based on GB / T 8642-2002.

[0200] Table 1 Performance of Titanium-Aluminum Metal Rotating Targets

[0201]

[0202]

[0203] As can be seen from Table 1, the titanium-aluminum alloy rotating target prepared by the method provided in this application is dense, with small grains, low oxygen content, high interfacial bonding strength, high overall target utilization rate, and low probability of local breakdown.

[0204] In summary, the titanium-aluminum metal rotating target provided in this application utilizes cold spraying technology to deposit a pure silver coating less than 5 μm thick on the surface of the back tube. Then, different proportions of elemental titanium and aluminum powders are deposited onto the back tube using vacuum cold spraying technology. Simultaneously, laser shock peening is applied to the titanium-aluminum deposition layer during deposition. Through repeated deposition and shock peening, a large-size rotating titanium-aluminum metal target is formed layer by layer. This method effectively improves material utilization, prevents oxidation and decomposition, and allows the target material to retain its original components completely. The resulting rotating target material is dense, has small grains, uniform structure, low gas content, and high interfacial bonding strength, significantly improving target performance. Furthermore, the target size is not limited; for example, a large rotating target with a size of 4 meters can be fabricated. In addition, the presence of the pure silver coating in the target material improves conductivity and sputtering uniformity. The dumbbell-shaped target design reduces raw material costs while significantly improving target utilization efficiency.

[0205] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a titanium-aluminum metal rotating target, characterized in that, Includes the following steps: S1: A pure silver coating is prepared on the surface of a stainless steel back tube using a conventional cold spraying method; The silver powder used to prepare the pure silver coating has a particle size of 1-5 μm; S2: A titanium-aluminum deposition layer is deposited on the surface of the pure silver coating using a vacuum cold spraying method. Simultaneously, the deposition layer is subjected to laser shock peening using a laser shock peening process. The titanium source and aluminum source for preparing the titanium-aluminum deposition layer are elemental titanium powder and elemental aluminum powder, respectively. The particle size of the elemental titanium powder is 0.1-30 μm, and the particle size of the elemental aluminum powder is 5-45 μm. The mass of the elemental titanium powder accounts for 1-50% of the total mass of the elemental titanium powder and the elemental aluminum powder. The working gas for vacuum cold spraying is helium; the spraying pressure is 2.5-3.5 MPa; the spraying temperature is 400-600℃; the spraying distance is 30 mm; and the vacuum degree during spraying is <1 kPa. S3: Repeat S2 until the total thickness of the titanium-aluminum deposited layer reaches the preset thickness; Before S1, the process also includes: performing controlled corrosion matrix roughening on the surface of the stainless steel back tube; the diameter of the matrix micro-pits corresponding to the controlled corrosion matrix roughening is 5μm and the depth is 5-8μm; S3 is followed by: S4: An additional 5-10 mm of titanium-aluminum deposition layer is deposited at both ends of the stainless steel back tube.

2. The preparation method according to claim 1, characterized in that, The purity of the silver powder is not less than 99.99%.

3. The preparation method according to claim 1, characterized in that, In S1, conventional cold spraying includes at least one of the following characteristics: Feature 1: The working gas is nitrogen; Feature 2: Spraying pressure is 3-6 MPa; Feature 3: Spraying temperature is 800-1000℃; Feature 4: Spraying distance is 30mm.

4. The preparation method according to claim 1, characterized in that, Before S2, the process also includes: laser cleaning of the oxide film on the surface of the pure silver coating.

5. The preparation method according to claim 1, characterized in that... The purity of the titanium powder is not less than 99.99%, and the purity of the aluminum powder is not less than 99.99%.

6. The preparation method according to claim 1, characterized in that, In S2, the laser shock peening process includes at least one of the following features: Feature 1: The diameter of the light spot is 4-10mm; Feature 2: The overlap rate of light spots is 1-25%; Feature 3: Peak pressure is 1.5-4 GPa.

7. A titanium-aluminum metal rotating target, characterized in that, It is prepared by the preparation method according to any one of claims 1-6.

8. The titanium-aluminum metal rotating target according to claim 7, characterized in that, The titanium-aluminum metal rotating target includes at least one of the following features: Feature 1: The titanium-aluminum metal rotating target is dumbbell-shaped; Feature 2: The thickness of the pure silver coating is <5μm; Feature 3: The total thickness of the titanium-aluminum deposited layer is 5-30 mm; Feature 4: The thickness of a single layer of the titanium-aluminum deposition layer is <1mm.

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