阅读说明：本技术 锂靶材组件的制造方法 (Method for manufacturing lithium target assembly ) 是由 齐大志 刘慧芳 程滋平 陈强 牟瀚波 杨诚 吴春敢 于 2019-01-08 设计创作，主要内容包括：本发明公开了一种锂靶材组件的制造方法,包括：提供锂靶坯,所述锂靶坯具有第一主表面和与第一主表面相反的第一背面；提供背板,所述背板具有第二主表面和与第二主表面相反的第二背面；对所述背板的第二主表面进行镀锂处理,形成镀锂层；将所述锂靶坯的第一主表面与所述背板的第二主表面上的镀锂层相对设置并贴合,形成初始组件；在真空环境中,向所述初始组件施加压力,使所述锂靶坯与所述镀锂层结合,完成锂靶坯与背板的绑定,从而形成锂靶材组件。本发明技术方案降低了锂靶坯与背板的绑定难度,提高了锂靶材组件生产制造的效率。(The invention discloses a manufacturing method of a lithium target assembly, which comprises the following steps: providing a lithium target blank having a first major surface and a first backside surface opposite the first major surface; providing a backing sheet having a second major surface and a second back surface opposite the second major surface; carrying out lithium plating treatment on the second main surface of the back plate to form a lithium plating layer; oppositely arranging and attaching the lithium plating layer on the first main surface of the lithium target blank and the second main surface of the back plate to form an initial assembly; and applying pressure to the initial assembly in a vacuum environment to combine the lithium target blank with the lithium plating layer to finish the binding of the lithium target blank and the back plate so as to form the lithium target assembly. The technical scheme of the invention reduces the binding difficulty of the lithium target blank and the back plate and improves the production and manufacturing efficiency of the lithium target assembly.)

1. A method of manufacturing a lithium target assembly, the method comprising:

providing a lithium target blank having a first major surface and a first backside surface opposite the first major surface;

providing a backing sheet having a second major surface and a second back surface opposite the second major surface;

carrying out lithium plating treatment on the second main surface of the back plate to form a lithium plating layer;

oppositely arranging and attaching the lithium plating layer on the first main surface of the lithium target blank and the second main surface of the back plate to form an initial assembly;

and applying pressure to the initial assembly in a vacuum environment to combine the lithium target blank with the lithium plating layer to finish the binding of the lithium target blank and the back plate so as to form the lithium target assembly.

2. The manufacturing method of claim 1, wherein the lithium plating process comprises one of evaporation, electrodeposition, and electroless plating; the thickness of the lithium plating layer is 100nm to 20 μm, preferably 1 μm to 10 μm.

3. The production method according to claim 1, wherein the lithium target blank is metallic lithium having a purity of 99.9% or more, or a lithium alloy having a mass percentage of metallic lithium of 60% or more; the back plate is made of metal or alloy, preferably copper, stainless steel, aluminum alloy, or a mixture thereof.

4. The method of manufacturing of claim 1, further comprising: heating one or more of the lithium target blank, the backing plate, or the entire initial assembly before, while, or after applying pressure to the initial assembly in a vacuum environment to complete the bonding of the lithium target blank to the backing plate.

5. The production method according to claim 4, wherein the heating temperature at which the lithium target blank is heated is 30 ℃ to 180 ℃, preferably 120 ℃ to 150 ℃; or, the heating temperature when heating the back plate is 30 ℃ to 180 ℃; preferably, the heating temperature is 120 ℃ to 150 ℃.

6. The method of manufacturing of claim 1, further comprising:

providing a mold having a cavity with both ends open, the cavity having the same cross-sectional shape as the lithium target blank,

placing the lithium target blank in the chamber prior to forming the initial assembly, or after forming the initial assembly but prior to applying pressure and/or heat, surrounding the lithium target blank with the mold.

7. The manufacturing method of claim 6, wherein the applying pressure to the initial assembly is performed while contacting the first back surface of the lithium target blank with a pressing block having the same cross-sectional shape as the cavity of the mold, so that the pressing block, the mold, and the back plate constitute an enclosed space enclosing the lithium target blank therein.

8. The manufacturing method according to claim 7, wherein at least the part of the pressuring block to be in contact with the lithium target material is made of or coated with a release material, or a layered release material is placed between the pressuring block and the lithium target blank, preferably the release material comprises polyamide 6(PA6), polyamide 66(PA66), Polyethylene (PE), Polyetheretherketone (PEEK), Polytetrafluoroethylene (PTFE), ceramics, oil or oiled film.

9. The manufacturing method according to claim 1, wherein the second main surface of the back sheet is subjected to a pretreatment comprising a cleaning and/or a surface roughening treatment, preferably the surface roughening treatment comprises forming convexo-concave different shapes on the surface by a physical or chemical method, before the lithium plating treatment is performed on the second main surface of the back sheet.

10. The method of manufacturing of claim 1, further comprising:

and after the binding of the lithium target blank and the back plate is finished, performing vacuum breaking operation, and taking out the lithium target assembly.

Technical Field

The invention relates to the technical field of metal targets, in particular to a manufacturing method of a lithium target assembly.

Background

Metallic lithium is a rare element with a density of 0.534g/cm³Being the lightest metal. Melting point 180.54 ℃ and boiling point 1317 ℃. The material has the characteristics of softness, high toughness, good ductility, good chemical activity, high negative potential, high specific energy, capability of reacting with a large amount of inorganic reagents and organic reagents and very violent reaction with water.

The metallic lithium target can be sputtered on glass to obtain electrochromic glass, is widely applied to the fields of buildings, airplanes, automobiles and the like, and is beneficial to energy conservation and environmental protection.

Because the melting point of the metal lithium is low, unstable and difficult to control, the target material cannot be prepared by the traditional methods such as powder metallurgy, spraying and the like. Chinese patent application No. 201510756173.0 discloses a method for casting lithium metal target, but the method is only suitable for casting rotary target. Currently, there is a need for industrially applicable techniques for manufacturing planar metallic lithium target assemblies.

Disclosure of Invention

The invention aims to provide a simple and efficient method for manufacturing a lithium target (especially a planar lithium target) suitable for industrial production.

The inventor finds that: the planar metal lithium target assembly can be relatively easily manufactured by the lithium target blank and the back plate through a vacuum welding technology, and the manufactured target assembly is not easy to generate air chambers, bulges and the like and has high strength. Furthermore, in order to reduce the binding difficulty between the lithium target blank and the back plate, the inventors have designed a technical scheme for forming a lithium plating layer on the back plate, thereby completing the present invention.

The purpose of the invention can be realized by the following technical scheme.

The invention provides a method for manufacturing a lithium target assembly, which comprises the following steps:

providing a lithium target blank having a first major surface and a first backside surface opposite the first major surface;

providing a backing sheet having a second major surface and a second back surface opposite the second major surface;

carrying out lithium plating treatment on the second main surface of the back plate to form a lithium plating layer;

oppositely arranging and attaching the lithium plating layer on the first main surface of the lithium target blank and the second main surface of the back plate to form an initial assembly;

and applying pressure to the initial assembly in a vacuum environment to combine the lithium target blank with the lithium plating layer to finish the binding of the lithium target blank and the back plate so as to form the lithium target assembly.

Optionally, the lithium plating process includes one of evaporation, electrodeposition, and electroless plating.

Alternatively, the thickness of the lithium-plated layer is 100nm to 20 μm, preferably 1 μm to 10 μm.

Optionally, the lithium target blank is metallic lithium with a purity equal to or greater than 99.9%, or the lithium target blank is a lithium alloy with a mass percentage of metallic lithium equal to or greater than 60%.

Optionally, the back plate is made of a metal or alloy, preferably copper, stainless steel, aluminum alloy, or a mixture thereof.

In certain embodiments, the above manufacturing method further comprises: heating one or more of the lithium target blank, the backing plate, the lithium plated layer on the backing plate, or the entire initial assembly, in a vacuum environment, before, simultaneously with, or after applying pressure to the initial assembly, to complete the bonding of the lithium target blank to the backing plate.

Optionally, the heating temperature when heating the lithium target blank is from 30 ℃ to 180 ℃, preferably from 120 ℃ to 150 ℃; or the heating temperature for heating the backboard or the lithium plating layer is 30-180 ℃, preferably 50-120 ℃.

In certain embodiments, the above manufacturing method further comprises:

providing a mold having a cavity with both ends open, the cavity having the same cross-sectional shape as the lithium target blank,

prior to forming the initial assembly, or after forming the initial assembly but prior to applying pressure and/or heat, placing a lithium target blank in the chamber, surrounding the lithium target blank with the mold.

Optionally, applying pressure to the initial assembly is performed with a pressure applicator block contacting a first back surface of a lithium target blank, the pressure applicator block having the same cross-sectional shape as the cavity of the mold, such that the pressure applicator block, the mold, and the backing plate constitute an enclosed space enclosing the lithium target blank therein.

Alternatively, at least the portion of the pressing block to be in contact with the lithium target material is made of or coated with a release material, or a layered release material is placed between the pressing block and the lithium target blank. Preferably, the release material comprises polyamide 6(PA6), polyamide 66(PA66), Polyethylene (PE), Polyetheretherketone (PEEK), Polytetrafluoroethylene (PTFE), ceramic, oil-containing or oiled film.

Optionally, at least the second main surface of the back sheet is subjected to a pretreatment comprising a cleaning and/or a surface roughening treatment, preferably the surface roughening treatment comprises forming a relief-varying shape on the surface by a physical or chemical method, prior to subjecting the second main surface of the back sheet to a lithium plating treatment.

In certain embodiments, the above manufacturing method further comprises:

and after the binding of the lithium target blank and the back plate is finished, performing vacuum breaking operation, and taking out the lithium target assembly.

The technical scheme of the invention has at least one of the following advantages:

1. the planar lithium target material component is manufactured by vacuum welding, the process is simple and easy to implement, and the investment cost is low;

2. the problems that a gas chamber and an air bag are easy to generate in the target material when the operation is carried out in a non-vacuum environment (a drying chamber and an argon glove box) are solved;

3. the production problem caused by the softness and viscosity of the metal lithium is solved, so that the production of the target assembly is simple and easy, and no raw material is wasted basically;

4. the manufactured lithium target material component has high strength, the tensile strength of the lithium target material component can reach more than 0.8Mpa, and the tensile strength is basically close to the tensile strength of the metal lithium.

5. The binding difficulty of the metal lithium target blank and the back plate is reduced, and the production efficiency of the metal lithium target material assembly is improved. Generally, the back plate and the lithium target blank are directly bound, and in order to achieve ideal binding strength, the binding time generally needs more than 3 hours; by the technical scheme of the invention, the required binding strength and binding effect can be achieved within 0.5 hour generally.

Drawings

FIG. 1 is a schematic flow diagram of one embodiment of the present invention.

Fig. 2 is a schematic structural view of the target blank in step S1 of the embodiment shown in fig. 1.

Fig. 3 is a schematic structural diagram of the back plate in step S1 in the embodiment shown in fig. 1.

Fig. 4 is a schematic structural diagram of the back plate after lithium plating in step S2 according to the embodiment shown in fig. 1.

Fig. 5 is a schematic structural diagram of the initial assembly in step S3 in the embodiment shown in fig. 1.

Fig. 6 is a schematic structural diagram of the embodiment shown in fig. 1 after the initial assembly is placed in step S4.

Fig. 7 is a schematic structural diagram of the target assembly in step S6 according to the embodiment shown in fig. 1.

FIG. 8 is a schematic structural view of the starting assembly in a comparative example (back sheet not lithium-plated).

FIG. 9 is a schematic view of the structure of the initial assembly after placement in a comparative example (back sheet not lithium-plated).

Fig. 10 is a schematic view of the structure of a target assembly produced in a comparative example (backing plate not lithium-plated).

Detailed Description

The following describes specific embodiments of the present invention. It is to be understood that other various embodiments can be devised and modified by those skilled in the art in light of the teachings of this disclosure without departing from the scope or spirit of the invention. The following detailed description is, therefore, not to be taken in a limiting sense.

In the description of the present invention, it is to be understood that the terms "first", "second", etc. are used only for convenience in describing the present invention and for simplicity in description, and thus, are not to be construed as limiting the present invention.

One aspect of the present invention provides a method of manufacturing a lithium target assembly, comprising: providing a lithium target blank having a first major surface and a first backside surface opposite the first major surface; providing a backing sheet having a second major surface and a second back surface opposite the second major surface; carrying out lithium plating treatment on the second main surface of the back plate to form a lithium plating layer; oppositely arranging and attaching the lithium plating layer on the first main surface of the lithium target blank and the second main surface of the back plate to form an initial assembly; and applying pressure to the initial assembly in a vacuum environment to combine the lithium target blank with the lithium plating layer to finish the binding of the lithium target blank and the back plate so as to form the lithium target assembly.

In the manufacturing method, the lithium target blank and the back plate are welded together by using the vacuum diffusion welding process and taking the first main surface of the lithium target blank as a first welding surface and the lithium-plated layer on the second main surface of the back plate as a second welding surface, so that the lithium target assembly is obtained.

The principle of diffusion welding is that atoms between two parts to be welded are diffused mutually at a certain temperature and under a certain pressure, and finally become a whole after a period of time, so that the binding is completed. Diffusion welding is easier to perform under vacuum conditions. The invention takes a vacuum environment as a specific environment for manufacturing the lithium target material assembly, and utilizes the vacuum diffusion welding process, so that the binding of the lithium target blank and the back plate can be promoted, and the gas inclusion between the target blank and the back plate can be prevented, thereby influencing the use effect. And moreover, the lithium plating layer is formed on the back plate, and the lithium target material assembly is formed by welding the lithium target blank and the lithium plating layer, so that the binding difficulty of the lithium target blank and the back plate is greatly reduced, and the production and manufacturing efficiency of the lithium target material assembly can be obviously improved.

The lithium target blank used in the present invention for manufacturing the target assembly may be a planar lithium target blank, typically having a thickness of 1-20mm, for example 2-10 mm. The material can be metal lithium with the purity of 99.9% or more, or lithium alloy with the mass percent of the metal lithium of 60% or more.

The backing plate is typically made of a metal or alloy, for example, copper (e.g., red copper), stainless steel, aluminum alloy, or a mixture thereof.

In the present invention, a lithium plating treatment is performed on the surface (second main surface) of the backing plate to be bonded to the lithium target blank to form a lithium plated layer. The thickness of the lithium-plated layer may be 100nm to 20 μm, preferably 1 μm to 10 μm, for example 5 μm to 10 μm.

The lithium plating process for forming the lithium plating layer may include a plating process such as evaporation, electrodeposition, electroless plating, and the like, and preferably, the surface plating is performed by a vacuum evaporation method.

As a substrate carrying the lithium target blank, the backing plate typically has a larger cross-sectional area than the lithium target blank. The shape of the target blank and backing plate may be determined according to the desired shape of the target assembly. For example, providing a backing plate and a target blank that are circular in cross-section and the diameter of the target blank is less than the diameter of the backing plate; and oppositely arranging the first welding surface of the target blank and the second welding surface of the back plate, and attaching the first welding surface and the second welding surface to form an initial assembly, preferably, the target blank protrudes out of the back plate. Or, providing that the cross sections of the back plate and the target blank are rectangular, and the length and the width of the target blank are not larger than the length and the width of the back plate; and oppositely arranging the first welding surface of the target blank and the second welding surface of the back plate, and attaching the first welding surface and the second welding surface to form an initial assembly, preferably, the target blank protrudes out of the back plate.

In the present invention, the backsheet, particularly the second main surface, may be degreased before the lithium-plated layer is formed. Degreasing can be performed by using an organic solvent, by using a machining method, by using an ultrasonic process, or by using a wire brush or the like.

In order to improve the binding strength of the lithium target blank and the backing plate, the second main surface of the backing plate may be subjected to surface roughening treatment. The surface roughening treatment refers to forming a rugged shape on the surface by a physical or chemical method. Physical methods of the surface roughening treatment may include roughening, sand blasting, and the like. The chemical process may include acid etching and water washing steps. In addition, the groove may also be formed on the second main surface by a mechanical method. The asperity shapes formed by the surface roughening treatment generally have a size of the order of micrometers, for example, several micrometers to several hundred micrometers.

The lithium metal is very soft, and even if the applied pressure is small, the lithium metal can be pressed to be very thin, and the lithium metal has strong viscosity and can be adhered to a processing tool frequently, so that the production and the product quality are affected. The invention designs special equipment for manufacturing a planar lithium target material assembly aiming at the characteristics of the lithium metal, and the special equipment comprises a mould and a pressing block matched with the mould.

Specifically, the manufacturing method of the target assembly of the invention adopts a special die which can be used for limiting the deformation of the lithium target and is provided with a cavity with two open ends, and the cross section shape of the cavity is the same as that of the lithium target blank, so that the die can surround the periphery of the lithium target blank when the lithium target blank is placed in the cavity of the die. The height of the mold cavity may be equal to or greater than the thickness of the lithium target blank to fully contain the target blank therein.

In accordance with the mold, the present invention also contemplates a press for applying pressure to the initial assembly, the press comprising a press block having the same cross-sectional shape as the cavity of the mold, such that when the press block is pressed against the first back surface of the lithium target blank, the press block, the mold and the backing plate form an enclosed space enclosing the target blank therein. The closed space completely covers the target blank, and ensures that the target blank does not deform or flow due to overlarge pressure when pressure is applied to the target blank and/or the target blank is heated.

In particular operations, the mold may be used to surround the periphery of the lithium target blank prior to forming the initial assembly, or after forming the initial assembly but prior to applying pressure and/or heat. Here, the step of forming the initial assembly may be performed in a non-vacuum environment, or the target blank and the backing plate may be separately placed in a vacuum environment or apparatus and then bonded to form the initial assembly.

Then, a vacuum diffusion welding step is performed, wherein the initial assembly is heated and applied with pressure (the sequence of heating and applying pressure can also be exchanged) in a vacuum environment, and the lithium target assembly is finally formed after a period of time. Here, the pressure may be applied by the pressure block, or the pressure may be applied to the rear plate while the pressure block is pressed against the first rear surface of the lithium target blank (forming the closed space). Because the target blank is limited in the closed space formed by the pressing block, the die and the back plate, the target blank can not deform or flow, so that higher pressure can be applied, the binding is firmer, and the material waste caused by the deformation of the target material is avoided.

In the present invention, the heating of the initial assembly may be heating of one or more of the lithium target blank, the backing plate, or the entire initial assembly. When the lithium target blank is heated, the heating temperature may be 30 ℃ to 180 ℃, preferably 120 ℃ to 150 ℃; the purpose of the heating is to increase the activity of the lithium atoms in the lithium target blank. When the back sheet (including the lithium-plated layer thereon) is heated, the heating temperature may be 30 to 180 ℃; preferably, the heating temperature is 120-150 ℃; the purpose of the heating is to increase the activity of the lithium atoms in the lithium-plated layer, but to avoid the coating from falling off or loosening.

The conditions when performing vacuum diffusion welding may include: the vacuum degree of the vacuum environment is 1x10^-3Pa to 100Pa, preferably 1X10^-3Pa to 1x10^-1Pa; the pressure applied to the lithium target blank and the back plate is 0.1MPa to 10 MPa; heating the initial assembly at a temperature of 30 ℃ to 180 ℃; the duration of the heating and pressurizing is 0.25 hour or more, preferably 0.5 hour or more.

In order to reduce or eliminate the problem that the production and the product quality are affected because the metal lithium is adhered to the processing tool, the invention can also arrange an anti-sticking material at the part of the pressing block and the mould, which is to be contacted with the lithium target blank. The release material may directly constitute the site where the pressing block and the mold are in contact with the lithium target blank, or may be present on the site in the form of a coating.

Since the problem of adhesion of the metallic lithium to the die can be solved by extruding the target material from the die by the pressing block, the anti-sticking material may be provided only on the pressing block.

As an alternative, a layered anti-sticking member may be separately provided, which is interposed between the pressing block and the lithium target blank while applying pressure and heat to the initial assembly.

The release material may be selected from polyamide 6(PA6), polyamide 66(PA66), Polyethylene (PE), Polyetheretherketone (PEEK), Polytetrafluoroethylene (PTFE), ceramics, oil-containing or oil-coated films, and the like.

After the welding is completed, the invention can also comprise a vacuum breaking operation for taking out the lithium target material assembly from the equipment. During vacuum breaking, dry air or argon can be adopted; preferably, argon is used for breaking the vacuum.

The invention may also include a post-weld cooling step.

Some embodiments and comparative examples of the present invention are described below with reference to the accompanying drawings.

Referring to fig. 1, fig. 1 is a schematic flow chart of an embodiment of a method for manufacturing a lithium target assembly according to the present invention, and the method for manufacturing a target assembly of the present embodiment includes the following basic steps:

step S1: providing a target blank and a back plate, wherein the surface to be welded of the target blank is a first welding surface, and the surface to be welded of the back plate is a second welding surface;

step S2: carrying out surface lithium plating treatment on the second welding surface of the back plate;

step S3: oppositely arranging and attaching the lithium plating layers of the first welding surface and the second welding surface to form an initial assembly;

step S4: placing the initial assembly in a vacuum environment or equipment, and coating the lithium target blank by using a closed space formed by a pressurizing block, a mould and a back plate;

step S5: vacuum is maintained, temperature is heated, pressure/pressure is applied for a certain time.

Step S6: and breaking vacuum, and taking out the target assembly.

Referring to fig. 1 to 3, step S1 is performed to provide a lithium target blank 10 (shown in fig. 2) and a backing plate 20 (shown in fig. 3), where the surface to be welded (first main surface) of the target blank 10 is a first welding surface 12, and the surface to be welded (first main surface) of the backing plate 20 is a second welding surface 21. The first back surface 11 is opposite to the first bonding surface 12 of the target blank 10, and the second back surface 22 is opposite to the second bonding surface 21 of the backing plate 20.

In the embodiment, the size of the lithium target blank 10 is phi 70mm, the thickness is 6mm, and the purity is more than 99.9 percent; the back plate 20 is made of red copper with the size of phi 75mm and the thickness of 5 mm.

Referring to fig. 1 to 4, step S2 is performed to perform surface lithium plating on the second soldering surface of the back plate. And (3) drying the back plate in a vacuum oven, and plating a layer of metal lithium on the second welding surface of the back plate in a film plating machine or other film plating equipment, wherein the thickness of the plating layer is controlled to be 5-10 mu m.

Referring to fig. 2, 4 and 5, step S3 is performed to dispose and attach the first bonding surface 12 of the target blank 10 opposite to the lithium-plated layer 23 on the second bonding surface 21 of the backing plate 20 to form the initial assembly 30.

Referring to fig. 1, 5 and 6, steps S4, S5 are performed to place the formed preliminary assembly 30 into a vacuum apparatus; surrounding the lithium target blank 10 by using a mold 40, starting a vacuum-pumping operation, and reducing the vacuum degree to 1x10^-1When Pa is lower, the pressing block 50 presses the first back surface 11 of the target blank 10 downward from above the mold 40, so that the target blank 10 is located in the closed space formed by the mold 40, the pressing block 50, and the backing plate 20. The first welding surface 12 of the target blank 10 is tightly attached to the lithium-plated layer 23 on the second welding surface 21 of the backing plate 20; the initial assembly 30 is heated to a temperature of 120 to 150 deg.C, which is about 120 deg.C in this embodiment. Maintaining the evacuation, pressurization and heating operations and associated vacuum, pressure and temperature values; the holding time in this example was 0.5 hour.

Referring to fig. 1 to 7, in step S6, the vacuum breaking operation is performed on the vacuum equipment to return to the normal pressure. The temperature is reduced and the pressure is removed and the target assembly 40 is removed (fig. 7).

Comparative example: and directly binding the lithium target blank and the back plate without performing lithium plating operation on the back plate.

Referring to fig. 8, 9 and 10 (the reference numerals in fig. 8-10 have the same meanings as those in fig. 5-7 except that the lithium plating layer 23 is not provided in fig. 8-10), the initial assembly 30 is constructed by disposing and attaching the first bonding surface 12 of the lithium target blank 10 opposite to the second bonding surface 21 of the backing plate 20; placing the initial assembly 30 into a vacuum apparatus; surrounding the target blank 10 by using the mold 40, starting the vacuum-pumping operation until the vacuum degree is reduced to 1x10^-1When Pa is less than or equal to Pa, the pressurizing block 50 applies a downward pressure to the first back surface 11 of the target blank 10 from above the mold 40 so that the target blank 10 is positioned between the mold 40 and the mold,The pressuring block 50 and the back plate 20 are formed in a closed space. The first welding surface 12 of the target blank 10 is tightly attached to the second welding surface 21 of the backing plate 20; the initial assembly 30 is heated to a temperature controlled at about 170 c. The evacuation, pressurization and heating operations and the associated vacuum, pressure and temperature values are maintained for a period of time. After the preset time is reached, vacuum breaking and other operations are carried out, and the target assembly 40 is taken out.

The processing results of the present example embodiment and the comparative example embodiment were compared by a plurality of tests, wherein the binding results (binding strength) of the lithium target blank to the back sheet are shown in the following table:

through the comparison, the embodiment of the invention can obviously shorten the time required by binding while reducing the heating temperature. When the binding strength is greater than 0.7MPa, the embodiment only needs 0.5h, while the comparative example needs more than 2h to achieve the binding strength of more than 0.7 MPa.

Although the present invention has been disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.