Welding method for nickel-aluminum alloy target material assembly

Abstract

The invention provides a welding method of a nickel-aluminum alloy target material assembly, which comprises the following steps: arranging a chromium-aluminum layer on the welding surface of a nickel-aluminum alloy target material, then assembling the nickel-aluminum alloy target material and a back plate, putting the nickel-aluminum alloy target material and the back plate into a sheath, and then sequentially carrying out degassing and hot isostatic pressing welding; and the molar ratio of the chromium element to the aluminum element in the chromium-aluminum layer is (0.4-0.6): 1. The specific plating layer is arranged on the welding surface of the nickel-aluminum alloy target material, and subsequent hot isostatic pressing welding is combined, so that the obtained nickel-aluminum alloy target material assembly does not have any deformation, and meanwhile, high-strength and high-binding-rate welding of the nickel-aluminum alloy target material and the back plate is realized. The welding method is simple in process, efficient and suitable for batch production.

Description

Technical Field

[0001] The invention belongs to the technical field of target assembly welding and relates to a welding method for a nickel-aluminum alloy target assembly. Background Art

[0002] Currently, metal sputtering targets are used as cathode materials in sputtering deposition technology. In the sputtering machine, positively charged cations strike the cathode, causing it to detach as molecules, atoms, or ions and redeposit on the anode surface. Because metal sputtering targets are often made of relatively expensive materials such as high-purity aluminum, copper, titanium, nickel, tantalum, and precious metals, more common materials are often used as backing plates in their manufacture. Backing plates provide support, cooling, and cost reduction for the target, and are commonly made of aluminum alloys or copper.

[0003] In the field of materials science, particularly in the application of high-strength alloys, nickel-aluminum alloys are widely used in a variety of demanding industrial environments due to their excellent mechanical properties and corrosion resistance. However, in the field of welding technology, how to effectively weld nickel-aluminum alloys to other materials to form a high-strength bond interface has long been a challenge for engineers.

[0004] While traditional welding methods, such as laser welding and electron beam welding, can achieve some success in welding nickel-aluminum alloys to other materials, these methods typically operate at high temperatures, which can easily lead to thermal damage at the weld interface, affecting performance and increasing production costs. Furthermore, existing welding techniques are unable to form a high-strength interface when welding nickel-aluminum alloys to other materials, further limiting the application of nickel-aluminum alloys.

[0005] In summary, developing a method that can achieve welding of nickel-aluminum alloys with other materials at a lower temperature and form a high-strength bonding interface is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a welding method for a nickel-aluminum alloy target assembly, by setting a specific coating on the welding surface of the nickel-aluminum alloy target and combining it with subsequent hot isostatic pressing welding to achieve high-strength and high-bonding rate welding between the nickel-aluminum alloy target and the back plate.

[0007] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0008] The present invention provides a welding method for a nickel-aluminum alloy target assembly, characterized in that the welding method comprises:

[0009] A chromium-aluminum layer is provided on the welding surface of the nickel-aluminum alloy target, and then the nickel-aluminum alloy target and the backing plate are assembled and placed in a sheath, followed by degassing and hot isostatic pressing welding;

[0010] The molar ratio of chromium element to aluminum element in the chromium-aluminum layer is (0.4-0.6):1, for example, it can be 0.42:1, 0.45:1, 0.46:1, 0.48:1, 0.5:1, 0.52:1, 0.55:1, 0.56:1 or 0.58:1, but is not limited to the listed values, and other values ​​within the numerical range are also applicable.

[0011] In the present invention, the mass percentage of aluminum element in the nickel-aluminum alloy target is 2%-3%, for example, it can be 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8% or 2.9%, etc., but is not limited to the listed values, and other values ​​within the numerical range are also applicable.

[0012] The welding method provided by the present invention achieves high-strength and high-bonding efficiency welding between the nickel-aluminum alloy target and the backing plate by applying a specific coating to the welding surface of the nickel-aluminum alloy target and subsequent hot isostatic pressing. This method is simple, efficient, and suitable for mass production, while maintaining the resulting nickel-aluminum alloy target assembly without any deformation.

[0013] It is worth noting that by specifically designing the composition of the coating, the contact diffusion between the nickel-aluminum alloy target and the backing plate is facilitated during the subsequent hot isostatic pressing welding process, and the difference in physical and chemical properties between the nickel-aluminum alloy target and the backing plate is reduced, thereby improving the welding strength and bonding rate.

[0014] As a preferred technical solution of the present invention, the nickel-aluminum alloy target is also cleaned and dried in sequence before the chromium-aluminum layer is provided.

[0015] As a preferred technical solution of the present invention, the chromium-aluminum layer is provided by PVD (physical vapor deposition).

[0016] In the present invention, the purity of the chromium-aluminum layer is ≥3N5.

[0017] Preferably, the thickness of the chromium-aluminum layer is 5-10 μm, for example, it can be 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm or 9.5 μm, etc., but is not limited to the listed values, and other values ​​within the numerical range are also applicable.

[0018] In the present invention, by controlling the thickness range of the chromium-aluminum layer on the target material welding surface, the stress distribution on the welding surface of the target material assembly after welding is uniform, and the diffusion performance and thermal conductivity between the target material and the back plate are also enhanced.

[0019] As a preferred technical solution of the present invention, the material of the back plate includes copper or aluminum alloy, preferably aluminum alloy.

[0020] Preferably, the back plate has a groove, and the bottom surface of the groove is the back plate welding surface.

[0021] In the present invention, the groove needs to be tested for assembly dimension tolerance. If the target material is cylindrical, the back plate groove also needs to be tested for roundness to ensure smooth subsequent assembly processing.

[0022] Preferably, the backboard is cleaned and dried in sequence before assembly.

[0023] In the present invention, cleaning is beneficial to improving welding quality; there is no specific limitation on the cleaning steps, as long as the stains and oil stains on the nickel-aluminum alloy target and the back plate can be effectively removed to ensure the cleanliness of the welding surface.

[0024] As a preferred technical solution of the present invention, the material of the sheath includes aluminum.

[0025] Preferably, the sheath is welded and vacuumed in sequence before degassing.

[0026] As a preferred technical solution of the present invention, the welding includes argon arc welding.

[0027] Preferably, the end point of the vacuuming is a vacuum degree ≤ 0.002 Pa.

[0028] As a preferred technical solution of the present invention, the degassing temperature is 300-400°C, for example, it can be 310°C, 320°C, 330°C, 340°C, 350°C, 360°C, 370°C, 380°C or 390°C, but is not limited to the listed values, and other values ​​within the numerical range are also applicable.

[0029] In the present invention, the sheath is degassed to remove air and other gases in the sheath to prevent oxidation during the subsequent hot isostatic pressing welding process.

[0030] Preferably, the degassing time is 2-4 hours, for example, it can be 2.2 hours, 2.5 hours, 2.6 hours, 2.8 hours, 3 hours, 3.2 hours, 3.5 hours, 3.6 hours or 3.8 hours, but is not limited to the listed values, and other values ​​within the numerical range are also applicable.

[0031] As a preferred technical solution of the present invention, the temperature of the hot isostatic pressing welding is 420-480°C, for example, it can be 425°C, 430°C, 435°C, 440°C, 445°C, 450°C, 455°C, 460°C, 465°C, 470°C or 475°C, but is not limited to the listed values, and other values ​​within the numerical range are also applicable.

[0032] Preferably, the pressure of the hot isostatic pressing welding is ≥105 MPa, for example, it can be 115 MPa, 120 MPa, 125 MPa, 130 MPa, 135 MPa, 140 MPa, 145 MPa, 150 MPa, 160 MPa or 170 MPa, but is not limited to the listed values. Other values ​​within the numerical range are also applicable, preferably 105-150 MPa.

[0033] As a preferred technical solution of the present invention, the heat preservation and pressure holding time of the hot isostatic pressing welding is 4-6h, for example, it can be 4.2h, 4.5h, 4.6h, 4.8h, 5h, 5.2h, 5.5h, 5.6h or 5.8h, but is not limited to the listed values, and other values ​​within the numerical range are also applicable.

[0034] In the present invention, by controlling the temperature, pressure and heat preservation and pressure holding time of hot isostatic pressing welding, it is ensured that a high-strength bonding interface is formed between the nickel-aluminum alloy target material and the back plate.

[0035] In the present invention, after the hot isostatic pressing welding is completed, the sheath is taken out from the hot isostatic pressing welding equipment and then air-cooled to room temperature.

[0036] As a preferred technical solution of the present invention, the welding method includes the following steps:

[0037] (1) a chromium-aluminum layer is provided on the welding surface of the nickel-aluminum alloy target, and then the nickel-aluminum alloy target and the backing plate are assembled and placed in a sheath;

[0038] The nickel-aluminum alloy target material is also cleaned and dried in sequence before the chromium-aluminum layer is provided;

[0039] The molar ratio of chromium to aluminum in the chromium-aluminum layer is (0.4-0.6):1; the chromium-aluminum layer is provided by PVD, and the thickness of the chromium-aluminum layer is 5-10 μm;

[0040] The back plate has a groove, the bottom surface of which is the welding surface of the back plate; the back plate is also cleaned and dried in sequence before assembly;

[0041] (2) welding, vacuuming, and degassing the package described in step (1) in sequence, and then hot isostatic pressing the degassed package;

[0042] The welding includes argon arc welding; the end point of the vacuuming is a vacuum degree of ≤0.002Pa; the temperature of the degassing is 300-400°C and the time is 2-4h;

[0043] The hot isostatic pressing welding temperature is 420-480° C., the pressure is ≥105 MPa, and the heat preservation and pressure holding time is 4-6 hours.

[0044] The numerical range described in the present invention includes not only the point values ​​listed above, but also any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The welding method provided by the present invention provides a specific coating on the welding surface of the nickel-aluminum alloy target material. By specifically designing the composition and thickness of the coating, the nickel-aluminum alloy target material and the back plate are facilitated to contact and diffuse with each other during the subsequent hot isostatic pressing welding process, and the difference in physical and chemical properties between the nickel-aluminum alloy target material and the back plate is reduced. Combined with the parameter range of the hot isostatic pressing welding, the obtained nickel-aluminum alloy target material assembly does not show any deformation, and high-strength and high-bonding rate welding of the nickel-aluminum alloy target material and the back plate is achieved at the same time, with a welding bonding rate of ≥99% and a welding strength of ≥60MPa. The welding method has a simple process, high efficiency, and is suitable for mass production. DETAILED DESCRIPTION

[0047] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0048] In the following examples and comparative examples, the mass percentage of aluminum in the nickel-aluminum alloy target material is 2.5%; the material of the aluminum alloy back plate is A6061 aluminum alloy.

[0049] Example 1

[0050] This embodiment provides a welding method for a nickel-aluminum alloy target assembly, the welding method comprising the following steps:

[0051] (1) a chromium-aluminum layer is provided on the welding surface of the nickel-aluminum alloy target, and then the nickel-aluminum alloy target and the aluminum alloy back plate are assembled and placed in an aluminum sheath;

[0052] The nickel-aluminum alloy target material is also cleaned and dried in sequence before the chromium-aluminum layer is provided;

[0053] The molar ratio of chromium to aluminum in the chromium-aluminum layer is 0.5:1; the purity of the chromium-aluminum layer is 3N5; the chromium-aluminum layer is formed by PVD, and the thickness of the chromium-aluminum layer is 8 μm;

[0054] The aluminum alloy back plate has a groove, and the bottom surface of the groove is the welding surface of the aluminum alloy back plate; the aluminum alloy back plate is also cleaned and dried in sequence before assembly;

[0055] (2) welding, vacuuming, and degassing the aluminum sheath described in step (1) in sequence, and then hot isostatic pressing the degassed aluminum sheath;

[0056] The welding includes argon arc welding; the end point of the vacuuming is a vacuum degree of 0.002 Pa; the degassing temperature is 350° C. and the time is 3 hours;

[0057] The hot isostatic pressing welding is performed at a temperature of 450° C., a pressure of 105 MPa, and a heat and pressure holding time of 5 hours.

[0058] Example 2

[0059] This embodiment provides a welding method for a nickel-aluminum alloy target assembly, the welding method comprising the following steps:

[0060] (1) a chromium-aluminum layer is provided on the welding surface of the nickel-aluminum alloy target, and then the nickel-aluminum alloy target and the aluminum alloy back plate are assembled and placed in an aluminum sheath;

[0061] The nickel-aluminum alloy target material is also cleaned and dried in sequence before the chromium-aluminum layer is provided;

[0062] The molar ratio of chromium to aluminum in the chromium-aluminum layer is 0.4:1; the purity of the chromium-aluminum layer is 3N5; the chromium-aluminum layer is formed by PVD, and the thickness of the chromium-aluminum layer is 10 μm;

[0063] The aluminum alloy back plate has a groove, and the bottom surface of the groove is the welding surface of the aluminum alloy back plate; the aluminum alloy back plate is also cleaned and dried in sequence before assembly;

[0064] (2) welding, vacuuming, and degassing the aluminum sheath described in step (1) in sequence, and then hot isostatic pressing the degassed aluminum sheath;

[0065] The welding includes argon arc welding; the end point of the vacuuming is a vacuum degree of 0.002 Pa; the degassing temperature is 300° C. and the time is 4 hours;

[0066] The hot isostatic pressing welding is performed at a temperature of 420° C., a pressure of 120 MPa, and a heat and pressure holding time of 6 hours.

[0067] Example 3

[0068] This embodiment provides a welding method for a nickel-aluminum alloy target assembly, the welding method comprising the following steps:

[0069] (1) a chromium-aluminum layer is provided on the welding surface of the nickel-aluminum alloy target, and then the nickel-aluminum alloy target and the aluminum alloy back plate are assembled and placed in an aluminum sheath;

[0070] The nickel-aluminum alloy target material is also cleaned and dried in sequence before the chromium-aluminum layer is provided;

[0071] The molar ratio of chromium to aluminum in the chromium-aluminum layer is 0.6:1; the purity of the chromium-aluminum layer is 3N5; the chromium-aluminum layer is formed by PVD, and the thickness of the chromium-aluminum layer is 5 μm;

[0072] The aluminum alloy back plate has a groove, and the bottom surface of the groove is the welding surface of the aluminum alloy back plate; the aluminum alloy back plate is also cleaned and dried in sequence before assembly;

[0073] (2) welding, vacuuming, and degassing the aluminum sheath described in step (1) in sequence, and then hot isostatic pressing the degassed aluminum sheath;

[0074] The welding includes argon arc welding; the end point of the vacuuming is a vacuum degree of 0.001 Pa; the degassing temperature is 400° C. and the time is 2 hours;

[0075] The hot isostatic pressing welding is performed at a temperature of 480° C., a pressure of 110 MPa, and a heat and pressure holding time of 4 hours.

[0076] Example 4

[0077] This embodiment provides a welding method for a nickel-aluminum alloy target assembly. Except that the thickness of the chromium-aluminum layer in step (1) is 2 μm, other conditions are the same as those in Example 1.

[0078] Example 5

[0079] This embodiment provides a welding method for a nickel-aluminum alloy target assembly. Except that the thickness of the chromium-aluminum layer in step (1) is 15 μm, other conditions are the same as those in Example 1.

[0080] Example 6

[0081] This embodiment provides a method for welding a nickel-aluminum alloy target assembly. Except that the temperature of the hot isostatic pressing welding in step (2) is 350° C., other conditions are the same as those in Example 1.

[0082] Example 7

[0083] This embodiment provides a method for welding a nickel-aluminum alloy target assembly. Except that the temperature of the hot isostatic pressing welding in step (2) is 600° C., other conditions are the same as those in Example 1.

[0084] Example 8

[0085] This embodiment provides a method for welding a nickel-aluminum alloy target assembly. Except that the pressure of the hot isostatic pressing welding in step (2) is 90 MPa, other conditions are the same as those in Example 1.

[0086] Comparative Example 1

[0087] This comparative example provides a welding method for a nickel-aluminum alloy target assembly. Except that the molar ratio of chromium to aluminum in the chromium-aluminum layer in step (1) is 1:0.5, other conditions are the same as those in Example 1.

[0088] Comparative Example 2

[0089] This comparative example provides a welding method for a nickel-aluminum alloy target assembly. Except that the molar ratio of chromium to aluminum in the chromium-aluminum layer in step (1) is 0.2:1, other conditions are the same as those in Example 1.

[0090] Comparative Example 3

[0091] This comparative example provides a method for welding a nickel-aluminum alloy target assembly. Except that the chromium-aluminum layer in step (1) is replaced by a chromium layer, other conditions are the same as those in Example 1.

[0092] Comparative Example 4

[0093] This comparative example provides a method for welding a nickel-aluminum alloy target assembly. Except that the chromium-aluminum layer in step (1) is replaced by an aluminum layer, other conditions are the same as those in Example 1.

[0094] Comparative Example 5

[0095] This comparative example provides a method for welding a nickel-aluminum alloy target assembly. Except that no chromium-aluminum layer is provided in step (1), other conditions are the same as those in Example 1.

[0096] The welding bonding rate and welding strength of the nickel-aluminum alloy target material assemblies obtained in the above embodiments and comparative examples were tested using a water immersion ultrasonic flaw detector and a tensile test. The results are shown in Table 1.

[0097] Table 1

[0098]

[0099]

[0100] From Table 1 we can see that:

[0101] (1) The welding method provided in Examples 1-3 of the present invention achieves high-strength and high-bonding rate welding between the nickel-aluminum alloy target and the back plate by providing a specific coating on the welding surface of the nickel-aluminum alloy target and combining it with subsequent hot isostatic pressing welding. The obtained nickel-aluminum alloy target assembly does not exhibit any deformation, and the welding rate of the obtained nickel-aluminum alloy target assembly is ≥99%, and the welding strength is ≥60 MPa.

[0102] (2) From the comparison between Example 1 and Examples 4-5, it can be seen that when the thickness of the chromium-aluminum layer is too thin, the thermal stress generated during the welding process cannot be effectively alleviated, thereby affecting the welding quality of the nickel-aluminum alloy target assembly; when the thickness of the chromium-aluminum layer is too thick, the heat conduction efficiency during the welding process is reduced, and the welding residual stress is easily increased, thereby affecting the welding strength and welding bonding rate;

[0103] (3) From the comparison between Example 1 and Examples 6-8, it can be seen that the temperature and pressure during hot isostatic pressing welding need to be controlled within an appropriate range to avoid adverse effects on the welding quality, so as to ensure the welding bonding rate and welding strength of the target assembly;

[0104] (4) From the comparison between Example 1 and Comparative Examples 1-2, it can be seen that when the proportion of chromium in the chromium-aluminum layer is not within the appropriate range, it is not conducive to better contact and diffusion between the nickel-aluminum alloy target and the backing plate, resulting in a decrease in the welding bonding rate and welding strength of the obtained nickel-aluminum alloy target assembly;

[0105] (5) From the comparison between Example 1 and Comparative Examples 3-4, it can be seen that, compared with the pure chromium layer or the pure aluminum layer, the chromium-aluminum transition layer is more conducive to the contact and diffusion between the nickel-aluminum alloy target and the backing plate, and can also effectively avoid the formation of hard and brittle intermetallic compounds, thereby improving the welding quality;

[0106] (6) From the comparison between Example 1 and Comparative Example 5, it can be seen that when the transition layer is not provided on the nickel-aluminum alloy target, the nickel-aluminum alloy target cannot form a high-strength bonding interface with the backing plate.

[0107] The applicant declares that the above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the scope of protection and disclosure of the present invention.

Claims

1. A welding method for a nickel-aluminum alloy target assembly, characterized in that: The welding method comprises: A chromium-aluminum layer is provided on the welding surface of the nickel-aluminum alloy target, and then the nickel-aluminum alloy target and the back plate are assembled and placed in a package, and then degassing and hot isostatic pressing welding are performed in sequence; The molar ratio of chromium element to aluminum element in the chromium-aluminum layer is (0.4-0.6):

1.

2. The welding method according to claim 1, characterized in that: The nickel-aluminum alloy target material is also cleaned and dried in sequence before the chromium-aluminum layer is provided.

3. The welding method according to claim 1 or 2, characterized in that: The chromium-aluminum layer is provided by PVD; Preferably, the chromium-aluminum layer has a thickness of 5-10 μm.

4. The welding method according to any one of claims 1 to 3, characterized in that: The material of the back plate includes copper or aluminum alloy; Preferably, the back plate has a groove, and the bottom surface of the groove is the back plate welding surface; Preferably, the back plate is cleaned and dried in sequence before being assembled.

5. The welding method according to any one of claims 1 to 4, characterized in that: The material of the package includes aluminum; Preferably, the package is welded and vacuumed in sequence before degassing.

6. The welding method according to claim 5, characterized in that: The welding comprises argon arc welding; Preferably, the end point of the vacuuming is a vacuum degree ≤ 0.002Pa.

7. The welding method according to any one of claims 1 to 6, characterized in that: The degassing temperature is 300-400°C; Preferably, the degassing time is 2-4 hours.

8. The welding method according to any one of claims 1 to 7, characterized in that: The temperature of the hot isostatic pressing welding is 420-480°C; Preferably, the hot isostatic pressing welding pressure is ≥105 MPa, preferably 105-150 MPa.

9. The welding method according to any one of claims 1 to 8, characterized in that: The heat preservation and pressure holding time of the hot isostatic pressing welding is 4-6 hours.

10. The welding method according to any one of claims 1 to 9, characterized in that: The welding method comprises the following steps: (1) a chromium-aluminum layer is provided on the welding surface of the nickel-aluminum alloy target, and then the nickel-aluminum alloy target and the back plate are assembled and placed in a sheath; The nickel-aluminum alloy target is also cleaned and dried in sequence before the chromium-aluminum layer is provided; The molar ratio of chromium to aluminum in the chromium-aluminum layer is (0.4-0.6):1; the chromium-aluminum layer is arranged in a manner including PVD, and the thickness of the chromium-aluminum layer is 5-10 μm; The back plate has a groove, and the bottom surface of the groove is the welding surface of the back plate; the back plate is also cleaned and dried in sequence before assembly; (2) welding, vacuuming and degassing the package described in step (1) in sequence, and then hot isostatic pressing the degassed package; The welding includes argon arc welding; the end point of the vacuuming is a vacuum degree of ≤0.002Pa; the degassing temperature is 300-400°C and the time is 2-4h; The hot isostatic pressing welding has a temperature of 420-480° C., a pressure of ≥105 MPa, and a heat preservation and pressure holding time of 4-6 hours.

Images