Cold bonding method of ferromagnetic target material and device for method

Abstract

The invention relates to the technical field of target material production, in particular to a cold bonding method of a ferromagnetic target material and a device for the method. The method comprises the following steps: firstly, producing a blank plate and a finished target blank, coating indium on the blank plate and the finished target blank, enabling the surfaces, with indium layers, of the blank plate and the finished target blank to be opposite to obtain a combined target piece, placing the combined target piece in a vacuum environment, applying pressure to enable the indium layers on the combined target piece to be combined together to obtain a semi-finished target material, and processing the semi-finished target material to obtain the finished target material. The device for the cold bonding method of the ferromagnetic target material can generate a vacuum environment and press a combined target piece. According to the method disclosed by the invention, heating is not needed, so that the target material is basically not bent in the pressing process.

Description

Technical Field

[0001] The invention relates to the technical field of target material production, and in particular to a cold bonding method of a ferromagnetic target material and a device used for the method. Background Art

[0002] Since ferromagnetic target materials have a shielding effect on magnetic fields, it is not easy for the magnetic field to pass through the ferromagnetic target blank. Therefore, the target blank needs to be made thinner, while the back plate needs to be made thicker. Figure 5 As shown in the figure, a commonly used ferromagnetic target material includes a back plate 4 and a target blank 5. In the prior art, the two are brazed together by indium. The material of the back plate 4 is generally a copper alloy, such as a copper-zirconium alloy, etc., and the target blank 5 is a nickel-iron alloy or other ferromagnetic materials. When brazing, the temperature of the two needs to be heated to above the melting point of indium. Since the thermal expansion coefficient of the copper alloy is much greater than that of nickel-iron, the ferromagnetic target material will bend greatly after the brazing is completed and cooled. To solve this problem, the patent with application number 201911395580.8 discloses a method for preparing a high-performance ferromagnetic target material. First, the target blank and the back plate are prepared, and the target blank is processed to the finished product thickness size, and then the temperature difference method is used for welding to ensure the flatness of the target material. The internal stress of the welding is eliminated by vibration aging. Finally, the target material is prepared by processing the back plate. The finished product is prepared. This method is suitable for preparing a large-area target blank with a diameter of Φ300-450mm. The large-area high-purity ferromagnetic metal target prepared by this method has good thickness uniformity and low welding stress. The invention provides a method for combining a back plate and a target material together without heating, thereby avoiding the problem of bending of the target material after brazing in the prior art. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a cold bonding method for ferromagnetic target materials in view of the above-mentioned technical deficiencies.

[0004] A cold bonding method for a ferromagnetic target material comprises the following steps:

[0005] S1. Firstly, a blank plate and a finished target blank are produced. The diameter of the blank plate is not less than the diameter of the finished back plate. The thickness of the blank plate is more than one millimeter greater than the thickness of the finished back plate. A second concave platform is provided on the top surface of the blank plate. The diameter of the second concave platform is equal to the diameter of the finished target blank. The thickness of the portion of the blank plate where the second concave platform is provided is not less than the thickness of the finished target blank.

[0006] S2, heating the blank, then coating the bottom surface of the second concave platform with indium, then cooling the blank to room temperature, and then processing the indium layer in the second concave platform to make its thickness equal to 0.2-0.4 mm;

[0007] S3, heating the finished target blank, then coating one of the top surface or the bottom surface of the finished target blank with indium, then cooling the finished target blank to room temperature, and then processing the indium layer on the finished target blank to make its thickness equal to 0.2-0.4 mm;

[0008] S4, placing the indium layer of the finished target blank obtained in step S3 into the blank plate obtained in step S2 and placing it into the second concave platform to obtain a combined target, then placing the combined target in a vacuum environment and applying pressure to the blank plate and the finished target blank in the axial direction of the finished target blank, so that the indium layers on the two are combined together to obtain a semi-finished target material;

[0009] S5. Process the semi-finished target material obtained in step S4 to obtain a finished target material.

[0010] The device for the cold bonding method of ferromagnetic target materials comprises a base tube and a pressing piece, wherein the interior of the base tube is a cavity and the top is an opening, the top surface of the base tube wall is provided with a groove, a sealing ring is provided in the groove, an exhaust pipe connected to the internal cavity of the base tube is provided on one side of the lower part of the base tube, a plurality of support blocks are provided on the outside of the base tube, threaded holes are provided on the support blocks, bolts are threadedly connected to the threaded holes, and the heads of the bolts are located above the support blocks, the pressing piece comprises a guide part for inserting into the base tube and slidingly connected thereto, a pressure head is provided at the lower end of the guide part, a disk body is provided at the upper end of the guide part, and a sealing pressure ring is provided on the bottom surface of the disk body for inserting into the groove and contacting with the top surface of the sealing ring to perform a sealing effect.

[0011] To further optimize the technical solution, the thickness of the sealing pressure ring is smaller than the width of the groove.

[0012] To further optimize the technical solution, the number of the support blocks is three, and the three support blocks are symmetrically distributed about the axis of the base tube.

[0013] To further optimize the technical solution, the outer edge of the lower end of the guide portion is provided with a chamfer.

[0014] To further optimize the technical solution, a first concave platform is provided on the bottom surface of the inner cavity of the base tube, and the diameter of the first concave platform is equal to the diameter of the blank plate.

[0015] To further optimize the technical solution, the bottom surface of the internal cavity of the base tube is provided with depressions on both sides of the first concave platform.

[0016] To further optimize the technical solution, the upper opening of the first concave platform is provided with a chamfer.

[0017] Compared with the prior art, the present invention has the following advantages: 1. No heating is required, and the target material will basically not bend during the pressing process; 2. The device used for the cold bonding method of ferromagnetic target materials can provide a vacuum environment, and the vacuum environment in the base tube causes the pressed parts to be subjected to downward atmospheric pressure, and combined with the weight of the pressed parts themselves, the pressed parts can provide downward pressure, so that no additional pressure equipment is required. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the base tube.

[0019] Figure 2 It is a structural schematic diagram of the pressed parts.

[0020] Figure 3 The diagram is a schematic structural diagram of the device for the cold bonding method of ferromagnetic target materials when in use.

[0021] Figure 4 Schematic diagram of the structure of the blank.

[0022] Figure 5 Schematic diagram of the structure of ferromagnetic target.

[0023] In the figure: 1. base tube; 11. support block; 12. depression; 13. first concave platform; 14. groove; 15. exhaust pipe; 16. sealing ring; 17. bolt; 2. pressing part; 21. disk body; 22. guide part; 23. pressure head; 24. sealing pressure ring; 3. blank plate; 31. second concave platform; 4. back plate; 5. target blank. DETAILED DESCRIPTION

[0024] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0025] Example 1

[0026] A cold bonding method for a ferromagnetic target material comprises the following steps:

[0027] S1. Combination Figure 4 and 5As shown, a blank plate 3 and a finished target blank 5 are first produced, the material of the blank plate 3 is copper alloy or titanium, the material of the target blank 5 is ferromagnetic material such as nickel-iron alloy, the diameter of the blank plate 3 is not less than the diameter of the finished back plate 4, the thickness of the blank plate 3 is more than one millimeter thicker than the thickness of the finished back plate 4, when the thickness of the target blank 5 is three millimeters, the blank plate 3 is preferably two millimeters thicker than the finished back plate 4 (the blank plate 3 is too thick and wastes material), the top surface of the blank plate 3 is provided with a second concave platform 31, the diameter of the second concave platform 31 is equal to the diameter of the finished target blank 5, and the thickness of the portion of the blank plate 3 provided with the second concave platform 31 is not less than the thickness of the finished target blank 5;

[0028] S2, heating the blank 3, and then coating the bottom surface of the second concave platform 31 with indium. When coating the indium, the temperature of the blank 3 is kept at about 180°C. An ultrasonic indium coating machine can be used to completely wet the molten indium with the bottom surface of the second concave platform 31, and the depth of the indium melt in the second concave platform 31 is greater than 0.5 mm. Then the blank 3 is cooled to room temperature, the indium melt solidifies, and then the indium layer in the second concave platform 31 is processed to make its thickness equal to 0.2-0.4 mm. The higher the surface finish of the processed indium layer, the better, preferably not less than Ra0.8. The surface of the processed indium layer needs to be kept clean and used as soon as possible after processing;

[0029] S3, heating the finished target blank 5, and then coating one of the top surface or the bottom surface of the finished target blank 5 with indium. When coating with indium, the temperature of the finished target blank 5 is maintained at about 180°C. An ultrasonic indium coating machine can be used to completely infiltrate the molten indium with the bottom surface or the top surface of the finished target blank 5, and then the finished target blank 5 is cooled to room temperature, and the indium melt solidifies. Then, the indium layer on the finished target blank 5 is processed to make its thickness equal to 0.2-0.4 mm. The higher the surface finish of the processed indium layer, the better, preferably not less than Ra0.8. The surface of the processed indium layer needs to be kept clean and used as soon as possible after processing; in order to reduce waiting time, step S2 and step S3 can be performed simultaneously;

[0030] S4, placing the indium layer of the finished target blank 5 obtained in step S3 toward the blank plate 3 obtained in step S2 and placing it in the second concave platform 31 to obtain a combined target, then placing the combined target in a vacuum environment and applying pressure to the blank plate 3 and the finished target blank 5 in the axial direction of the finished target blank 5. Since indium is very soft, softer than lead, and easy to deform, when most of the air originally existing between the two is eliminated, the indium layer deforms under a certain pressure so that the area of ​​atomic-level contact between the two is larger. The pressure is preferably 1-4 kilograms per square centimeter (1 kilogram is equivalent to 9.8 Newtons), so that the indium layers on the two are combined together to obtain a semi-finished target material; since there is no heating, the semi-finished target material will basically not bend;

[0031] S5, processing the semi-finished target material obtained in step S4, that is, processing according to the drawing of the finished target material to obtain the finished target material. The processing mainly removes the part around the second concave platform 31 on the top surface of the blank plate 3.

[0032] Example 2

[0033] Combination Figure 1-4 As shown, a device for the cold bonding method of the ferromagnetic target material in Example 1 can generate a vacuum environment and press the combined target. It includes a base tube 1 and a pressing piece 2. The base tube 1 is hollow inside and open at the top. A groove 14 is provided on the top surface of the wall of the base tube 1. A sealing ring 16 is provided in the groove 14. An exhaust pipe 15 connected to the internal cavity of the base tube 1 is provided on one side of the lower part of the base tube 1. When in use, the exhaust pipe 15 is connected to a vacuum pump that needs to be prepared separately through a pipeline. A plurality of support blocks 11 are provided on the outside of the base tube 1. A threaded hole is provided on the support block 11. The threaded hole is threadedly connected to a bolt 17. The head of the bolt 17 is located at the bottom of the base tube 1. Above the support block 11, the pressing part 2 includes a guide part 22 for inserting into the base tube 1 and slidingly connected thereto, a pressure head 23 is arranged at the lower end of the guide part 22, and the diameter of the pressure head 23 is not less than the diameter of the finished target blank 5, and a disk body 21 is arranged at the upper end of the guide part 22, and a sealing pressure ring 24 is arranged on the bottom surface of the disk body 21 for inserting into the groove 14 and contacting with the top surface of the sealing ring 16 to play a sealing role. The groove 14 should be as deep as possible, and the height of the sealing ring 16 should be as high as possible so that it can withstand a larger deformation. When in use, combined with Figure 3As shown, first place the combined target on the bottom surface of the inner cavity of the base tube 1, with the side where the target blank 5 is located facing upwards, and then insert the guide part on the pressing piece 2 into the base tube 1 (for lubrication, vacuum silicone grease can be applied to the inner wall of the base tube 1). Under the action of gravity, the pressing piece 2 slides down, and the height of the top of the bolt 17 should be adjusted so that after the bottom surface of the sealing pressure ring 24 has been in contact with the top surface of the sealing ring 16 with a certain pressure (the effect of the gravity of the pressing piece 2) and plays a sealing role and before the bottom surface of the pressure head 23 contacts the top surface of the target blank 5 (at this time, the indium layer will not be combined with a large area, and the air between the two indium layers can be fully extracted by the vacuum pump, and it is not easy to have gas residue. At this time, the disk body 21 is not in contact with the top of the base tube 1, and there is still sufficient distance between the two so that the disk body 21 can be lowered later; and the pressure head 23 and the target blank 5 are spaced apart. The distance between them should be as small as possible so that the subsequent deformation of the sealing ring 16 will not be too large), the top surface of the bolt 17 supports the disk 21, so that the pressing part 2 cannot continue to descend, and then the vacuum pump is turned on to evacuate. When the vacuum degree reaches the requirement (preferably about 0.001Pa), the bolt 17 is turned to make it descend and no longer contact with the disk 21, so that the pressure head 23 is pressed on the top surface of the target blank 5. Under the action of atmospheric pressure and the gravity of the pressing part 2, the pressure head 23 produces the required pressure on the target blank 5, so that the target blank 5 can apply the required pressure to the indium layer. This state is maintained for at least 3 hours, and the pressing is completed. At this time, most of the contact surfaces between the two layers of indium are combined together, so that the target blank 5 and the blank plate 3 are combined together by indium. After that, the vacuum in the base tube 1 can be destroyed, the pressing part 2 can be lifted or hoisted, and then the semi-finished target material obtained can be taken out. Since both indium layers are located in the second concave platform 31 and the diameter of the second concave platform 31 is equal to the diameter of the finished target blank 5, the indium at the edge of the indium layer is not easy to be squeezed out from the edge of the second concave platform 31, which plays a certain sealing role, so that the amount of indium between the target blank 5 and the blank plate 3 will not be reduced, and there is no need to worry about no indium or too little indium between the target blank 5 and the blank plate 3 after the pressing is completed. In order to enhance the sealing and lubricity, vacuum silicone grease can be applied to the outer surface of the sealing ring 16 so that the sealing ring 16 is not easily damaged when deformed (pressed down).

[0034] Furthermore, the thickness of the sealing ring 24 ( Figure 3 The left and right directions in the figure are slightly smaller than the width of the groove 14 ( Figure 3 In the left and right direction, the sealing ring 24 can be easily inserted into the groove 14, and the processing accuracy of the sealing ring 24 does not need to be very high, thereby reducing the cost.

[0035] Furthermore, the number of the support blocks 11 is three, and the three support blocks 11 are symmetrically distributed about the axis of the base tube 1 .

[0036] Furthermore, the outer edge of the lower end of the guide portion 22 is provided with a chamfer, so that it is easy to insert it into the base tube 1.

[0037] Furthermore, a first concave platform 13 is provided on the bottom surface of the inner cavity of the base tube 1 , and the diameter of the first concave platform 13 is equal to the diameter of the blank 3 . The first concave platform 13 can play a role in positioning the combined target.

[0038] Furthermore, the bottom surface of the internal cavity of the base tube 1 is provided with recesses 12 on both sides of the first recess 13, and the recess 12 extends into a part below the first recess 13. When the semi-finished target material obtained by pressing is taken out from the base tube 1, the fingers can be extended through the recess 12 to the bottom of the edge of the blank 3, so that the semi-finished target material can be easily taken out.

[0039] Furthermore, the upper opening of the first concave platform 13 is provided with a chamfer, so that the assembled target is easily placed in the first concave platform 13 .

[0040] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A cold bonding method for ferromagnetic target materials, Features The following steps are involved: S1. First, a blank plate (3) and a finished target blank (5) are produced, wherein the diameter of the blank plate (3) is not less than the diameter of the finished back plate (4), the thickness of the blank plate (3) is greater than the thickness of the finished back plate (4) by more than one millimeter, the top surface of the blank plate (3) is provided with a second concave platform (31), the diameter of the second concave platform (31) is equal to the diameter of the finished target blank (5), and the thickness of the portion of the blank plate (3) provided with the second concave platform (31) is not less than the thickness of the finished target blank (5); S2, heating the blank (3), then coating the bottom surface of the second concave platform (31) with indium, then cooling the blank (3) to room temperature, and then processing the indium layer in the second concave platform (31) to a thickness of 0.2-0.4 mm; S3, heating the finished target blank (5), then coating one of the top surface or the bottom surface of the finished target blank (5) with indium, then cooling the finished target blank (5) to room temperature, and then processing the indium layer on the finished target blank (5) to make its thickness equal to 0.2-0.4 mm; S4, placing the indium layer of the finished target blank (5) obtained in step S3 toward the blank plate (3) obtained in step S2 into the second concave platform (31) to obtain a combined target, then placing the combined target in a vacuum environment and applying pressure to the blank plate (3) and the finished target blank (5) in the axial direction of the finished target blank (5), so that the indium layers on the two are combined together to obtain a semi-finished target material; S5. Process the semi-finished target material obtained in step S4 to obtain a finished target material.

2. A device for the cold bonding method of a ferromagnetic target material according to claim 1, Features: The invention comprises a base tube (1) and a pressing piece (2), wherein the base tube (1) is hollow inside and has an opening at the top, a groove (14) is provided on the top surface of the wall of the base tube (1), a sealing ring (16) is provided in the groove (14), an exhaust pipe (15) connected to the internal cavity of the base tube (1) is provided on one side of the lower part of the base tube (1), and a plurality of support blocks (11) are provided on the outside of the base tube (1), and threaded holes are provided on the threaded holes to which bolts are threadedly connected. (17), the head of the bolt (17) is located above the support block (11), the pressing part (2) includes a guide part (22) for inserting into the base tube (1) and slidably connected thereto, a pressure head (23) is provided at the lower end of the guide part (22), a disk body (21) is provided at the upper end of the guide part (22), and a sealing pressure ring (24) is provided on the bottom surface of the disk body (21) for inserting into the groove (14) and contacting with the top surface of the sealing ring (16) to perform a sealing effect.

3. The device for the cold bonding method of ferromagnetic target material according to claim 2, Features: The thickness of the sealing pressure ring (24) is smaller than the width of the groove (14).

4. The device for the cold bonding method of ferromagnetic target material according to claim 2, Features: The number of the support blocks (11) is three, and the three support blocks (11) are symmetrically distributed about the axis of the base tube (1).

5. The device for the cold bonding method of ferromagnetic target material according to claim 2, Features: The outer edge of the lower end of the guide portion (22) is provided with a chamfer.

6. The device for cold bonding of ferromagnetic target materials according to any one of claims 2 to 5, Features: A first concave platform (13) is provided on the bottom surface of the internal cavity of the base tube (1), and the diameter of the first concave platform (13) is equal to the diameter of the blank plate (3).

7. The device for the cold bonding method of ferromagnetic target material according to claim 6, Features: The bottom surface of the internal cavity of the base tube (1) is provided with recesses (12) on both sides of the first recessed platform (13).

8. The device for the cold bonding method of ferromagnetic target material according to claim 6, Features: The upper opening of the first concave platform (13) is provided with a chamfer.

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