A method of welding a WTi target assembly

Abstract

The present application relates to a kind of welding methods of WTi target assembly, the welding method includes: WTi target material, aluminum back plate and cover plate are assembled, then are placed into package and are sequentially degassed and welded;Wherein, the welding surface of the WTi target material is provided with groove;The welding surface of the aluminum back plate is treated with alkali;The assembly is aluminum back plate and cover plate with WTi target material as center symmetric assembly.The welding method provided by the present application, by setting groove in the welding surface of target material, treating the welding surface of back plate with alkali and specific assembly mode, the effective welding of WTi target material and aluminum back plate is realized, the generation of internal stress is also significantly reduced, no crack is generated, the sputtering effect is strengthened, and the service life is long.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of target material welding, in particular to a WTi target assembly welding method. BACKGROUND

[0002] The WTi target material is made by powder metallurgy sintering, and the hardness after sintering is relatively high, and the product is relatively brittle. It is not easy to diffuse weld with aluminum alloy or copper alloy back plate material, and it is easy to crack or even crack under a large stress.

[0003] CN103834923A discloses a method for manufacturing a tungsten-titanium target material. In the method, the tungsten-titanium alloy powder is first compacted in the edge area of the vacuum hot-pressing sintering mold, and then the entire tungsten-titanium alloy powder is compacted again. After the first and second compactions, the tungsten-titanium alloy powder completely fills all areas of the vacuum hot-pressing sintering mold, so that the tungsten-titanium target blank obtained after vacuum hot-pressing sintering does not have defects such as insufficient density and pores in the edge portion.

[0004] CN104213083A discloses a method for manufacturing a tungsten-titanium target material. The method includes mechanically crushing a waste target material to form particles, providing a powder raw material for manufacturing the target material, mixing the particles and the powder raw material, and then placing them in a mold for hot-pressing sintering to form a target material. The method can greatly improve the utilization rate of the target material, thereby avoiding waste of the target material and saving costs. In addition, compared with the process of directly hot-pressing sintering the waste target material with the powder raw material, the hot-pressing sintering process temperature and pressure are low when recycling the waste target material, thereby further saving process costs.

[0005] When welding, the temperature and pressure are generally increased to the required temperature and pressure, and then the temperature and pressure are maintained. During the temperature and pressure maintaining process, the target material and the back plate are fully diffused. After the temperature and pressure maintaining process is completed, the temperature and pressure need to be reduced. During the cooling process, the product will shrink. Because the materials of the target material and the back plate are different, the thermal expansion coefficients are also different, which causes a large deformation of the target material and the back plate during the cooling process. The thermal expansion coefficients of the WTi target material and the aluminum alloy material differ by several times, and a large deformation of the two materials occurs after diffusion welding. During the deformation process, the WTi target material bears a large stress, and after being taken out of the furnace, the stress is released, and the WTi target material is prone to cracking, has a short service life, and has an unsatisfactory sputtering effect. SUMMARY

[0006] In view of the problems in the prior art, the purpose of the present application is to provide a welding method of WTi target assembly, by which effective welding of WTi target and aluminum back plate can be realized, and the generation of internal stress is significantly reduced, no cracks are generated, the sputtering effect is strengthened, and the service life is long.

[0007] To achieve this purpose, the present application adopts the following technical solutions:

[0008] The present application provides a welding method of WTi target assembly, which comprises: assembling WTi target, aluminum back plate and cover plate, and then placing them in a package for degassing treatment and welding in sequence.

[0009] Among them, the welding surface of the WTi target is provided with a groove; the welding surface of the aluminum back plate is treated with alkali; and the assembly is symmetrically assembled with the WTi target as the center.

[0010] The welding method provided by the present application realizes effective welding of WTi target and aluminum back plate by setting a groove on the welding surface of the target, treating the welding surface of the back plate with alkali and using a specific assembly method, significantly reduces the generation of internal stress, generates no cracks, strengthens the sputtering effect and has a long service life.

[0011] As a preferred technical solution of the present application, the width of the groove is 2-4mm, for example, it can be 2mm, 2.2mm, 2.4mm, 2.6mm, 2.8mm, 3mm, 3.2mm, 3.4mm, 3.6mm, 3.8mm or 4mm, etc., but is not limited to the listed values, and other unlisted values within this range are also applicable.

[0012] Preferably, the vertical depth of the groove is 0.5-1.5mm, for example, it can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm or 1.5mm, etc., but is not limited to the listed values, and other unlisted values within this range are also applicable.

[0013] Preferably, the pitch of the groove is 3-5mm, for example, it can be 3mm, 3.2mm, 3.4mm, 3.6mm, 3.8mm, 4mm, 4.2mm, 4.4mm, 4.6mm, 4.8mm or 5mm, etc., but is not limited to the listed values, and other unlisted values within this range are also applicable.

[0014] In the present application, the groove can be a rectangular groove, an inverted triangular groove or an inverted trapezoidal groove, etc., and other shapes are also possible.

[0015] As a preferred technical solution of the present application, the alkali treatment is to treat the welding surface of the aluminum back plate with an alkali solution.

[0016] Preferably, the alkali solution comprises a sodium hydroxide solution and / or a potassium hydroxide solution.

[0017] Preferably, the concentration of the alkali solution is 6-12 mol / L, for example, it can be 6 mol / L, 7 mol / L, 8 mol / L, 9 mol / L, 10 mol / L, 11 mol / L, or 12 mol / L, etc., but is not limited to the listed values, and other values not listed in this range are also applicable.

[0018] Preferably, the time of the alkali treatment is 10-25 min, for example, it can be 10 min, 12 min, 14 min, 16 min, 18 min, 20 min, 22 min, 24 min, or 25 min, etc., but is not limited to the listed values, and other values not listed in this range are also applicable.

[0019] As a preferred technical solution of the present application, the temperature of the degassing treatment is 300-500℃, for example, it can be 300℃, 350℃, 400℃, 450℃, or 500℃, etc., but is not limited to the listed values, and other values not listed in this range are also applicable.

[0020] Preferably, the holding time of the degassing treatment is ≥2h, for example, it can be 2h, 2.5h, 3h, 3.5h, 4h, or 4.5h, etc., but is not limited to the listed values, and other values not listed in this range are also applicable.

[0021] As a preferred technical solution of the present application, the end-point vacuum degree of the degassing treatment is ≤5×10 -3 Pa, for example, it can be 5×10 -3 Pa, 4×10 -3 Pa, 3×10 -3 Pa, 2×10 -3 Pa, or 1×10 -3 Pa, etc., but is not limited to the listed values, and other values not listed in this range are also applicable.

[0022] As a preferred technical solution of the present application, the welding is diffusion welding.

[0023] As a preferred technical solution of the present application, the temperature of the welding is 350-550℃, for example, it can be 350℃, 400℃, 450℃, 500℃, or 550℃, etc., but is not limited to the listed values, and other values not listed in this range are also applicable.

[0024] As a preferred technical scheme of the present application, the welding pressure is ≥ 80 MPa, for example, it can be 80 MPa, 85 MPa, 90 MPa, 95 MPa, 100 MPa or 105 MPa, etc., but is not limited to the listed values, and other unlisted values within the range are also applicable.

[0025] As a preferred technical scheme of the present application, the welding holding time is ≥ 2 h, for example, it can be 2 h, 2.5 h, 3 h, 3.5 h, 4 h or 4.5 h, etc., but is not limited to the listed values, and other unlisted values within the range are also applicable.

[0026] As a preferred technical scheme of the present application, the welding method comprises assembling the WTi target material, the aluminum back plate and the cover plate, and then placing them in a package for degassing treatment and welding in sequence.

[0027] The welding surface of the WTi target material is provided with a groove; the welding surface of the aluminum back plate is subjected to alkali treatment; the assembly is a symmetrical assembly of the aluminum back plate and the cover plate with the WTi target material as the center; the width of the groove is 2-4 mm; the vertical depth of the groove is 0.5-1.5 mm; the spacing of the groove is 3-5 mm; the alkali treatment is a treatment of the welding surface of the aluminum back plate with an alkali solution; the concentration of the alkali solution is 6-12 mol / L; and the time of the alkali treatment is 10-25 min.

[0028] The welding surface in the present application refers to the surface where the target material and the back plate are in contact; a gasket such as a stainless steel skin or a graphite paper is provided between the cover plate and the target material to prevent them from being welded together.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] (1) In the present application, the alkali treatment of the welding surface of the back plate forms a meta-aluminate layer, and the coupling effect between the groove provided on the welding surface of the target material and the specific assembly mode reduces the generation of internal stress and does not form cracks, thereby strengthening the sputtering effect.

[0031] (2) The meta-aluminate layer formed after the alkali treatment of the welding surface of the back plate in the present application can strengthen the welding effect of the WTi target material and the aluminum back plate, and significantly enhance the welding strength of the WTi target material and the aluminum back plate. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a schematic diagram of the assembly mode of the WTi target material and the aluminum back plate in Example 1 of the present application.

[0033] In the figure: 1-cover plate, 2-target material, 3-aluminum back plate.

[0034] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0035] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0036] Example 1

[0037] This embodiment provides a welding method for WTi target assembly. The welding method includes: assembling the WTi target 2, aluminum backplate 3 and cover plate 1, and then placing them into a sleeve for degassing and welding in sequence.

[0038] The WTi target 2 has a groove on its welding surface; the aluminum backplate 3 undergoes alkali treatment on its welding surface; the assembly consists of the aluminum backplate 3 and the cover plate 1 symmetrically assembled around the WTi target 2. Figure 1 As shown; the width of the groove is 3mm; the vertical depth of the groove is 1mm; the spacing between the grooves is 4mm; the groove is a rectangular groove; the alkaline treatment involves treating the welding surface of the aluminum backplate with an alkaline solution; the alkaline solution is a sodium hydroxide solution; the concentration of the alkaline solution is 10mol / L; the alkaline treatment time is 15min; the degassing treatment temperature is 400℃; the holding time of the degassing treatment is 2h; the final vacuum degree of the degassing treatment is 5×10⁻⁶. -3 Pa; the welding is diffusion welding; the welding temperature is 457℃; the welding pressure is 80MPa; the welding holding time is 2h.

[0039] The resulting WTi target assembly is free from cracks and deformation, exhibits excellent welding bonding, and has a long service life.

[0040] Example 2

[0041] This embodiment provides a welding method for WTi target assembly. The welding method includes: assembling the WTi target, aluminum backplate and cover plate, and then placing them into a sleeve for degassing and welding in sequence.

[0042] The welding surface of the WTi target material is provided with a groove; the welding surface of the aluminum back plate is subjected to alkali treatment; the assembly is symmetrical assembly of the aluminum back plate and the cover plate with the WTi target material as the center; the width of the groove is 2mm; the vertical depth of the groove is 1.5mm; the spacing of the groove is 5mm; the groove is an inverted triangular groove; the alkali treatment is treatment of the welding surface of the aluminum back plate with an alkali solution; the alkali solution is a potassium hydroxide solution; the concentration of the alkali solution is 6mol / L; the time of the alkali treatment is 25min; the temperature of the degassing treatment is 310℃; the holding time of the degassing treatment is 3h; the terminal vacuum degree of the degassing treatment is 4x10 -3 Pa; the welding is diffusion welding; the temperature of the welding is 357℃; the pressure of the welding is 90MPa; and the holding time of the welding is 2.7h.

[0043] The obtained WTi target assembly is free of cracks and deformation, has good welding combination, and has a long service life.

[0044] Embodiment 3

[0045] The embodiment provides a welding method of a WTi target assembly, and the welding method comprises the following steps: assembling a WTi target material, an aluminum back plate and a cover plate, and then sequentially performing degassing treatment and welding in a package.

[0046] The welding surface of the WTi target material is provided with a groove; the welding surface of the aluminum back plate is subjected to alkali treatment; the assembly is symmetrical assembly of the aluminum back plate and the cover plate with the WTi target material as the center; the width of the groove is 4mm; the vertical depth of the groove is 0.5mm; the spacing of the groove is 3mm; the groove is an inverted trapezoidal groove; the alkali treatment is treatment of the welding surface of the aluminum back plate with an alkali solution; the alkali solution is a sodium hydroxide solution; the concentration of the alkali solution is 12mol / L; the time of the alkali treatment is 10min; the temperature of the degassing treatment is 477℃; the holding time of the degassing treatment is 2.5h; the terminal vacuum degree of the degassing treatment is 3x10 -3 Pa; the welding is diffusion welding; the temperature of the welding is 547℃; the pressure of the welding is 97MPa; and the holding time of the welding is 3.8h.

[0047] The obtained WTi target assembly is free of cracks and deformation, has good welding combination, and has a long service life.

[0048] Embodiment 4

[0049] The embodiment provides a welding method of a WTi target assembly, and the welding method comprises the following steps: assembling a WTi target material, an aluminum back plate and a cover plate, and then sequentially performing degassing treatment and welding in a package.

[0050] The welding surface of the WTi target material is provided with a groove; the welding surface of the aluminum back plate is subjected to alkali treatment; the assembly is symmetrically assembled with the WTi target material as the center; the width of the groove is 2.7 mm; the vertical depth of the groove is 1.17 mm; the spacing of the groove is 3.4 mm; the groove is a rectangular groove; the alkali treatment is to treat the welding surface of the aluminum back plate with an alkali solution; the alkali solution is a sodium hydroxide solution; the concentration of the alkali solution is 9.7 mol / L; the time of the alkali treatment is 17 min; the degassing treatment temperature is 467℃; the holding time of the degassing treatment is 2.3 h; the terminal vacuum degree of the degassing treatment is 3.2*10 -3 Pa; the welding is diffusion welding; the welding temperature is 517℃; the welding pressure is 87 MPa; and the holding time of the welding is 3.1 h.

[0051] The obtained WTi target material assembly is free of cracks and deformation, has good welding combination, and has a long service life.

[0052] Comparative Example 1

[0053] The difference from Example 1 is only that the welding surface of the target material is not provided with a groove, and the obtained WTi target material assembly has large internal stress, forms cracks and deforms.

[0054] Comparative Example 2

[0055] The difference from Example 1 is only that the welding surface of the aluminum back plate is not subjected to alkali treatment, and the obtained WTi target material assembly has not eliminated internal stress, forms cracks, and has poor target sputtering effect.

[0056] Comparative Example 3

[0057] The difference from Example 1 is only that the alkali treatment of the welding surface of the aluminum back plate is replaced by acid treatment, and the obtained WTi target material assembly has not eliminated internal stress, forms cracks, and has poor target sputtering effect.

[0058] Comparative Example 4

[0059] The difference from Example 1 is only that the vertical depth of the groove is 0.2 mm, and the obtained WTi target material assembly has not completely eliminated internal stress, forms cracks, and has poor target sputtering effect.

[0060] Comparative Example 5

[0061] The difference from Example 1 is only that the vertical depth of the groove is 2 mm, and the obtained WTi target material assembly is not firmly welded, and has poor target sputtering effect. Although the internal stress is effectively eliminated, the welding is not firm.

[0062] Comparative Example 6

[0063] The difference from the example 1 is that the width of the groove is 1mm, the WTi target assembly is not welded firmly, the sputtering effect of the target is poor, and cracks are formed due to the incomplete elimination of internal stress.

[0064] Comparative example 7

[0065] The difference from the example 1 is that the width of the groove is 6mm, the WTi target assembly is not welded firmly, the sputtering effect of the target is poor.

[0066] Comparative example 8

[0067] The difference from the example 1 is that the cover plate is not arranged, the WTi target assembly is not welded firmly, the sputtering effect of the target is poor, and cracks are formed due to the incomplete elimination of internal stress.

[0068] It can be seen from the results of the above examples and comparative examples that, in the present application, the generation of internal stress is reduced by the coupling effect between the aluminate layer formed on the welding surface of the back plate after alkali treatment and the groove arranged on the welding surface of the target, and the specific assembly mode, cracks are not formed, and the sputtering effect is strengthened. The aluminate layer formed on the welding surface of the back plate after alkali treatment in the present application can strengthen the welding effect of the WTi target and the aluminum back plate, and significantly enhance the welding strength of the WTi target and the aluminum back plate.

[0069] The applicant declares that the present application is illustrated by the above examples to explain the detailed structural features of the present application, but the present application is not limited to the above detailed structural features, that is, it does not mean that the present application must rely on the above detailed structural features to be implemented. It should be understood by those skilled in the art that any improvement of the present application, equivalent replacement of the components selected by the present application, addition of auxiliary components, selection of specific modes, etc. fall within the protection scope and disclosure scope of the present application.

[0070] The preferred embodiments of the present application are described in detail above, but the present application is not limited to the specific details in the above embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application.

[0071] In addition, it should be noted that each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction, and in order to avoid unnecessary repetition, the present application will not further describe various possible combination manners.

[0072] In addition, various different embodiments of the present application can also be combined in any manner, as long as it does not deviate from the idea of the present application, and it should also be considered as disclosed by the present application.

Claims

1. A method of welding a WTi target assembly, characterized by, The welding method comprises assembling a WTi target material, an aluminum back plate and a cover plate, and then placing them into a package for degassing treatment and welding in sequence. The welding surface of the WTi target material is provided with a groove; the welding surface of the aluminum back plate is subjected to alkali treatment; the assembly is symmetrical assembly of the aluminum back plate and the cover plate with the WTi target material as the center; the vertical depth of the groove is 0.5-1.5 mm; and the width of the groove is 2-4 mm. The alkali treatment is treatment of the welding surface of the aluminum back plate with an alkali solution. The concentration of the alkali solution is 6-12 mol / L. The time of the alkali treatment is 10-25 min.

2. The welding method of claim 1, wherein, The spacing of the grooves is 3-5 mm.

3. The welding method of claim 1, wherein, The alkali solution comprises a sodium hydroxide solution and / or a potassium hydroxide solution.

4. The welding method of claim 1, wherein, The temperature of the degassing treatment is 300-500℃.

5. The welding method of claim 1, wherein, The holding time of the degassing treatment is ≥2 h.

6. The welding method of claim 1, wherein, The end vacuum of the degassing treatment is ≤ 5 x 10 - 3 Pa.

7. The welding method of claim 1, wherein, The welding is diffusion welding.

8. The welding method of claim 1, wherein, The temperature of the welding is 350-550℃.

9. The welding method of claim 1, wherein, The pressure of the welding is ≥80 MPa.

10. The welding method of claim 1, wherein, The holding time of the welding is ≥2 h.

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