A method for preparing a copper-zinc alloy back plate, a copper-zinc alloy back plate and applications thereof

Abstract

The present invention provides a method for preparing a copper-zinc alloy back plate, a copper-zinc alloy back plate and an application thereof, wherein the preparation method comprises: (I) providing a copper-zinc alloy blank; (II) subjecting the blank to at least one hot forging treatment to obtain an intermediate ingot; and (III) subjecting the intermediate ingot to a first-stage heat treatment, a rolling treatment and a second-stage heat treatment in sequence to obtain a rough alloy back plate. The present invention has a simple process, low requirements on equipment during the production process, and the internal structure of the manufactured back plate is uniform and fine.

Description

Technical Field

[0001] The invention belongs to the technical field of manufacturing back plates for sputtering target materials, and relates to a preparation method of a copper-zinc alloy back plate, a copper-zinc alloy back plate and applications thereof. Background Art

[0002] In the production of semiconductor chips, high-purity titanium sputtering target is an extremely important material, generally composed of titanium target blank and back plate. The titanium target blank is directly involved in the sputtering coating, and the back plate plays the role of support, installation, cooling, etc. in the sputtering coating process. It is made of copper alloy to save manufacturing costs. The titanium target blank has a large rebound ability during processing and welding, and is not easy to weld. Therefore, in order to improve the welding pass rate of titanium sputtering target, the copper alloy back plate is required to have moderate hardness and uniform internal structure. Copper-zinc alloy is generally used to process the high-purity titanium sputtering target back plate.

[0003] CN113106362A provides a method for manufacturing a target back plate with a concave surface, wherein the method comprises annealing a flat blank in a vacuum environment or an inert gas environment at an annealing temperature of 380°C to 860°C and an annealing time of 0.4h to 4.1h to form an annealed flat blank, and then forging a concave blank multiple times using a forging die with a protrusion under the same temperature conditions, and then annealing the concave blank in a vacuum environment or an inert gas environment to finally form a target back plate with a concave surface. However, the annealing in a vacuum environment or an inert gas environment has relatively high requirements on the processing equipment, and the blank after annealing is directly die-forged, and the internal structure uniformity is poor.

[0004] CN102534518A provides a method for making a back plate, which includes placing a metal material into a vacuum melting furnace for melting and casting, performing five-stage forging on the casting to form a back plate blank, and then performing a low-temperature solid solution aging treatment on the back plate blank to form a back plate, thereby obtaining a back plate with a refined and uniform internal structure. However, the use of a vacuum melting furnace to melt the casting also places high demands on the production equipment, and the casting must be forged in five stages subsequently, so the process is relatively complicated.

[0005] Therefore, it is very important to provide a method for manufacturing a back plate that is simple in process and suitable for high-purity titanium sputtering target materials. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for preparing a copper-zinc alloy backplane, a copper-zinc alloy backplane and applications thereof, which have simple processes and low requirements on equipment during the production process, and at the same time, the internal structure of the manufactured backplane is uniform and fine.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for preparing a copper-zinc alloy back plate, the preparation method comprising:

[0009] (I) Providing copper-zinc alloy billets;

[0010] (II) subjecting the blank to at least one hot forging treatment to obtain an intermediate ingot;

[0011] (III) The intermediate ingot is subjected to a first-stage heat treatment, a rolling treatment and a second-stage heat treatment in sequence to obtain a rough alloy back plate.

[0012] The present invention manufactures the alloy back plate by sequentially performing hot forging, first-stage heat treatment, rolling and second-stage heat treatment on the blank, which has low equipment requirements and simple process. The internal structure of the back plate finally produced is uniform and fine, meeting the use requirements of high-purity titanium sputtering targets.

[0013] As a preferred technical solution of the present invention, in step (I), the components of the copper-zinc alloy blank include: 59-62wt% copper, 0.5-1.0wt% tin, and the balance zinc.

[0014] The mass ratio of copper can be, for example, 59wt%, 59.5wt%, 60wt%, 60.5wt%, 60.8wt%, 61wt%, 61.5wt%, 61.8wt% or 62wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0015] The mass ratio of tin may be, for example, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt% or 1.0wt%, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0016] Preferably, the method for making the blank comprises:

[0017] After being mixed according to the mass percentage of the metal components, the materials are placed in a continuous casting furnace and smelted by medium frequency induction. After the metal is fully melted, it is continuously cast into a rod-shaped billet.

[0018] Preferably, the aspect ratio of the rod-shaped blank is 1:(0.8-1.5), for example, it can be 1:0.8, 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4 or 1:1.5, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0019] As a preferred technical solution of the present invention, in step (II), the hot forging treatment includes: performing a preheating treatment and at least one continuous forging treatment on the blank in sequence.

[0020] Preferably, the temperature of the preheat treatment is 700-850°C, for example, it can be 700°C, 720°C, 730°C, 750°C, 760°C, 780°C, 800°C, 810°C, 820°C, 830°C, 840°C or 850°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0021] The present invention can reduce the forging force required in the continuous forging process through preheating treatment, so that the force applied by forging can be greatly reduced, and the plasticity of the material can be improved to prevent deformation or cracking during the forging process.

[0022] Preferably, the blank is placed in a resistance furnace for preheating treatment.

[0023] Preferably, the blank is continuously forged using an air hammer.

[0024] As a preferred technical solution of the present invention, the continuous forging process is carried out in the following manner:

[0025] The blank is stretched to 130-160% of the initial length, and then roughened to the initial length.

[0026] The blank may be stretched to 130%, 135%, 140%, 145%, 150%, 155% or 160% of the initial length, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0027] Preferably, the continuous forging process is repeated at least three times, for example, four times, five times, six times, seven times, eight times, nine times or ten times, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0028] Preferably, the length of the drawing in two adjacent continuous forging processes decreases in sequence. That is, the length of the drawing in each continuous forging process is greater than the length of the drawing in the next continuous forging process. For example, when the continuous forging process is repeated three times, the blank is drawn to 160% of the initial length for the first time, and then roughened to the initial length; the blank is drawn to 150% of the initial length for the second time, and then roughened to the initial length; the blank is drawn to 130% of the initial length for the third time, and then roughened to the initial length. In the present invention, the drawing length in the repeated continuous forging process gradually decreases, so that the deformation of the blank in the previous forging is greater than the deformation in the next forging, which is more conducive to uniform crushing of the internal structure of the blank.

[0029] It should be noted that the stretching in the present invention refers to a forging process in which the cross-sectional area of ​​the blank is reduced and the length is increased by forging with an air hammer. The roughening refers to a forging process in which the thickness of the blank is reduced and the cross-sectional area is increased by forging with an air hammer. The continuous forging process of the present invention is conducive to refining the grains of the blank, and makes the grains tightly compacted together, making the internal structure more compact.

[0030] Preferably, the thickness of the intermediate ingot is 1 / 2 to 2 / 3 of the initial thickness of the blank, for example, 1 / 2, 3 / 5 or 2 / 3, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0031] Preferably, the preparation method further comprises: after the hot forging treatment, performing a first cooling treatment on the intermediate ingot.

[0032] Preferably, the first cooling process comprises air cooling.

[0033] As a preferred technical solution of the present invention, in step (III), the temperature of the heat treatment is 300-500°C, for example, it can be 300°C, 320°C, 350°C, 380°C, 400°C, 430°C, 450°C, 480°C or 500°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0034] Preferably, the heat treatment time is 3 to 6 hours, for example, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours or 6 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0035] Preferably, the preparation method further comprises: performing a second cooling treatment after the first stage heat treatment.

[0036] Preferably, the second cooling process comprises water cooling.

[0037] The present invention can release the stress between the grains inside the intermediate ingot, reduce its hardness and brittleness, and reduce the risk of deformation in subsequent processing by performing a heat treatment on the intermediate ingot.

[0038] As a preferred technical solution of the present invention, the calendering rate of the calendering treatment is 10-20%, for example, it can be 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0039] It should be noted that the calendering in the present invention refers to passing the intermediate ingot after a period of heat treatment through a series of horizontal roller gaps rotating in opposite directions, so that the intermediate ingot is subjected to extrusion and extension to become a thin sheet product with a certain thickness, width and smooth surface. The present invention does not specifically limit the calendering process, and any calendering process known to those skilled in the art can be used.

[0040] The rolling ratio (%) in the present invention = (the thickness of the dough strip before the rolling treatment - the thickness of the dough strip after the rolling treatment) / the thickness of the dough strip before the rolling treatment.

[0041] As a preferred technical solution of the present invention, the temperature of the second stage heat treatment is 300-350°C, for example, it can be 300°C, 305°C, 310°C, 315°C, 320°C, 330°C, 340°C, 345°C or 350°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0042] Preferably, the time of the second stage heat treatment is 15 to 30 minutes, for example, it can be 15 minutes, 18 minutes, 20 minutes, 22 minutes, 25 minutes, 28 minutes or 30 minutes, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0043] Preferably, the preparation method further comprises: performing a third cooling treatment after the second stage heat treatment.

[0044] Preferably, the third cooling treatment includes water cooling.

[0045] The present invention can further release the stress between the grains inside the intermediate ingot and reduce the risk of deformation by performing two-stage heat treatment on the intermediate ingot.

[0046] As a preferred technical solution of the present invention, the preparation method also includes: leveling and machining the rough alloy back plate in sequence so that the flatness of the rough alloy back plate is ≤0.2μm and the roughness is 0.5-1.0μm, thereby obtaining a copper-zinc alloy back plate.

[0047] The roughness may be, for example, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm or 1.0 μm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0048] The machining includes a turning process to form grooves on the welding surface of the copper-zinc alloy back plate so as to be welded with the titanium sputtering target.

[0049] In order to help those skilled in the art better understand the overall technical solution and working process of the present invention, the present invention exemplarily provides the following specific steps for preparing a copper-zinc alloy backplane:

[0050] (1) mixing the metal components according to the mass percentage of 59-62wt% copper, 0.5-1.0wt% tin, and the balance zinc, placing the metal in a continuous casting furnace, using medium frequency induction melting, and continuously casting the metal into a rod-shaped billet after the metal is fully melted;

[0051] (2) placing a rod-shaped blank with an aspect ratio of 1:(0.8-1.5) in a box-type resistance furnace for preheating treatment at a temperature of 700-850° C. After reaching the preheating temperature, the rod-shaped blank is continuously forged with an air hammer, first stretched to 130-160% of the initial length, and then roughened to the initial length, and repeated at least three times, and the stretched lengths in two adjacent continuous forging treatments are successively reduced to obtain an intermediate ingot with a thickness of 1 / 2-2 / 3 of the initial thickness of the rod-shaped blank, and then subjected to a first cooling treatment;

[0052] (3) subjecting the intermediate ingot to a heat treatment at a temperature of 300 to 500° C. for a holding time of 3 to 6 hours, followed by a second cooling treatment;

[0053] (4) rolling the intermediate ingot, with a rolling rate of 10 to 20%;

[0054] (5) performing a second heat treatment on the intermediate ingot after the rolling treatment at a temperature of 300 to 350° C. for a holding time of 15 to 30 minutes, and then performing a third cooling treatment to obtain a rough alloy back plate;

[0055] (6) The rough alloy back plate is leveled and turned in sequence, so that the flatness of the rough alloy back plate is ≤0.2 μm and the roughness is 0.5-1.0 μm, thereby obtaining a copper-zinc alloy back plate.

[0056] In a second aspect, the present invention provides a copper-zinc alloy back plate, and the copper-zinc alloy back plate is prepared by the preparation method described in the first aspect.

[0057] In a third aspect, the present invention provides an application of the copper-zinc alloy back plate described in the second aspect, wherein the copper-zinc alloy back plate is used for titanium sputtering targets.

[0058] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes 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.

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] The present invention provides a method for preparing a copper-zinc alloy back plate, a copper-zinc alloy back plate and applications thereof. The alloy back plate is manufactured by sequentially subjecting a blank to hot forging treatment, a first-stage heat treatment, a rolling treatment and a second-stage heat treatment. The equipment requirements are low, and the internal structure of the back plate finally produced is uniform and fine, which meets the requirements for the use of high-purity titanium sputtering targets. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 A cross-sectional view of a copper-zinc alloy back plate provided in one embodiment of the present invention;

[0062] Figure 2 A top view of a copper-zinc alloy back plate provided for one specific embodiment of the present invention.

[0063] Among them, 1-copper-zinc alloy back plate; 2-welding surface; 3-groove. DETAILED DESCRIPTION

[0064] It should be understood that, in the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0065] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0066] In a specific embodiment, the present invention provides a method for preparing a copper-zinc alloy back plate, the preparation method comprising:

[0067] (1) mixing the metal components according to the mass percentage of 59-62wt% copper, 0.5-1.0wt% tin, and the balance zinc, placing the metal in a continuous casting furnace, using medium frequency induction melting, and continuously casting the metal into a rod-shaped billet after the metal is fully melted;

[0068] (2) placing a rod-shaped blank with an aspect ratio of 1:(0.8-1.5) in a box-type resistance furnace for preheating treatment at a temperature of 700-850° C. After reaching the preheating temperature, the rod-shaped blank is continuously forged with an air hammer, first stretched to 130-160% of the initial length, and then roughened to the initial length, and repeated at least three times, and the stretched lengths in two adjacent continuous forging treatments are successively reduced to obtain an intermediate ingot with a thickness of 1 / 2-2 / 3 of the initial thickness of the rod-shaped blank, and then subjected to a first cooling treatment;

[0069] (3) subjecting the intermediate ingot to a heat treatment at a temperature of 300 to 500° C. for a holding time of 3 to 6 hours, followed by a second cooling treatment;

[0070] (4) rolling the intermediate ingot, with a rolling rate of 10 to 20%;

[0071] (5) performing a second heat treatment on the intermediate ingot after the rolling treatment at a temperature of 300 to 350° C. for a holding time of 15 to 30 minutes, and then performing a third cooling treatment to obtain a rough alloy back plate;

[0072] (6) The rough alloy back plate is leveled and turned in sequence, so that the flatness of the rough alloy back plate is ≤0.2 μm and the roughness is 0.5-1.0 μm, thereby obtaining a copper-zinc alloy back plate 1.

[0073] In another specific embodiment, the present invention provides a copper-zinc alloy back plate 1, and the copper-zinc alloy back plate 1 is prepared by a preparation method provided in a specific embodiment. Figure 1 and Figure 2 As shown, the welding surface 2 of the copper-zinc alloy back plate 1 forms a groove 3 so as to be welded with the titanium sputtering target.

[0074] Example 1

[0075] This embodiment provides a method for preparing a copper-zinc alloy backplane, comprising the following steps:

[0076] (1) The materials are prepared according to the mass percentage of the metal components of 60wt% copper, 0.8wt% tin, and the balance zinc, and are placed in a continuous casting furnace, and medium frequency induction melting is adopted. After the metal is fully melted, it is continuously cast into a rod-shaped billet;

[0077] (2) placing a rod-shaped billet with an aspect ratio of 1:1 in a box-type resistance furnace for preheating treatment at a temperature of 780° C. After reaching the preheating temperature, the rod-shaped billet is subjected to three consecutive forging treatments using an air hammer. The first time, the rod-shaped billet is stretched to 160% of the initial length and then roughened to the initial length. The second time, the rod-shaped billet is stretched to 140% of the initial length and then roughened to the initial length. The third time, the rod-shaped billet is stretched to 135% of the initial length and then roughened to the initial length to obtain an intermediate ingot having a thickness of 1 / 2 of the initial thickness of the rod-shaped billet, which is then air-cooled.

[0078] (3) The intermediate ingot is subjected to a heat treatment at 400°C for 5 hours, followed by water cooling;

[0079] (4) The intermediate ingot is subjected to a calendering treatment, and the calendering rate is 15%;

[0080] (5) performing a second-stage heat treatment on the intermediate ingot after the rolling treatment at a temperature of 320° C. for a holding time of 25 min, followed by water cooling to obtain a rough alloy back plate;

[0081] (6) The rough alloy back plate is leveled and turned in sequence, so that the flatness of the rough alloy back plate is ≤0.2 μm, the surface roughness is 0.8 μm, and a groove 3 is formed on its welding surface 2 to obtain a copper-zinc alloy back plate 1.

[0082] The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment both have a uniform organizational structure.

[0083] Example 2

[0084] This embodiment provides a method for preparing a copper-zinc alloy backplane, comprising the following steps:

[0085] (1) The materials are prepared according to the mass percentage of the metal components of 59wt% copper, 1.0wt% tin, and the balance of zinc, and are placed in a continuous casting furnace, and medium frequency induction melting is adopted. After the metal is fully melted, it is continuously cast into a rod-shaped billet;

[0086] (2) placing a rod-shaped blank with an aspect ratio of 1:0.8 in a box-type resistance furnace for preheating treatment at a temperature of 700° C. After reaching the preheating temperature, the rod-shaped blank is subjected to three consecutive forging treatments using an air hammer. The first time, the rod-shaped blank is stretched to 160% of the initial length and then roughened to the initial length. The second time, the rod-shaped blank is stretched to 150% of the initial length and then roughened to the initial length. The third time, the rod-shaped blank is stretched to 130% of the initial length and then roughened to the initial length to obtain an intermediate ingot having a thickness of 2 / 3 of the initial thickness of the rod-shaped blank, which is then air-cooled.

[0087] (3) The intermediate ingot is subjected to a heat treatment at 300°C for 6 hours, followed by water cooling;

[0088] (4) rolling the intermediate ingot with a rolling rate of 20%;

[0089] (5) performing a second-stage heat treatment on the intermediate ingot after the rolling treatment at a temperature of 300° C. for a holding time of 20 min, followed by water cooling to obtain a rough alloy back plate;

[0090] (6) The rough alloy back plate is leveled and turned in sequence, so that the flatness of the rough alloy back plate is ≤0.2 μm, the surface roughness is 0.7 μm, and a groove 3 is formed on its welding surface 2 to obtain a copper-zinc alloy back plate 1.

[0091] The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment both have a uniform organizational structure.

[0092] Example 3

[0093] This embodiment provides a method for preparing a copper-zinc alloy backplane, comprising the following steps:

[0094] (1) The materials are prepared according to the mass percentage of the metal components of 61wt% copper, 0.9wt% tin, and the balance zinc, and are placed in a continuous casting furnace, and medium frequency induction melting is adopted. After the metal is fully melted, it is continuously cast into a rod-shaped billet;

[0095] (2) placing a rod-shaped billet with an aspect ratio of 1:1.2 in a box-type resistance furnace for preheating treatment at a temperature of 800° C. After reaching the preheating temperature, the rod-shaped billet is subjected to three consecutive forging treatments using an air hammer. The first time, the rod-shaped billet is stretched to 150% of the initial length and then roughened to the initial length. The second time, the rod-shaped billet is stretched to 140% of the initial length and then roughened to the initial length. The third time, the rod-shaped billet is stretched to 130% of the initial length and then roughened to the initial length to obtain an intermediate ingot having a thickness of 3 / 5 of the initial thickness of the rod-shaped billet, which is then air-cooled.

[0096] (3) The intermediate ingot is subjected to a heat treatment at 450°C for 3.5 h and a holding time of 28 min, followed by water cooling;

[0097] (4) The intermediate ingot is subjected to a calendering treatment, and the calendering rate is 18%;

[0098] (5) performing a second-stage heat treatment on the intermediate ingot after the rolling treatment at a temperature of 350° C., and then water cooling to obtain a rough alloy back plate;

[0099] (6) The rough alloy back plate is leveled and turned in sequence, so that the flatness of the rough alloy back plate is ≤0.2 μm, the surface roughness is 0.6 μm, and a groove 3 is formed on its welding surface 2 to obtain a copper-zinc alloy back plate 1.

[0100] The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment both have a uniform organizational structure.

[0101] Example 4

[0102] This embodiment provides a method for preparing a copper-zinc alloy backplane, comprising the following steps:

[0103] (1) The materials are prepared according to the mass percentage of the metal components of 62wt% copper, 1.0wt% tin, and the balance of zinc, and are placed in a continuous casting furnace, and medium frequency induction melting is adopted. After the metal is fully melted, it is continuously cast into a rod-shaped billet;

[0104] (2) placing a rod-shaped billet with an aspect ratio of 1:1.5 in a box-type resistance furnace for preheating treatment at a temperature of 800° C. After reaching the preheating temperature, the rod-shaped billet is subjected to three consecutive forging treatments using an air hammer. The first time, the rod-shaped billet is stretched to 160% of the initial length and then roughened to the initial length. The second time, the rod-shaped billet is stretched to 150% of the initial length and then roughened to the initial length. The third time, the rod-shaped billet is stretched to 140% of the initial length and then roughened to the initial length to obtain an intermediate ingot having a thickness of 3 / 5 of the initial thickness of the rod-shaped billet, which is then air-cooled.

[0105] (3) The intermediate ingot is subjected to a heat treatment at 450°C for 4 h and a holding time of 18 min, followed by water cooling;

[0106] (4) The intermediate ingot is subjected to a calendering treatment, and the calendering rate is 15%;

[0107] (5) performing a second-stage heat treatment on the intermediate ingot after the rolling treatment at a temperature of 330° C., and then water cooling to obtain a rough alloy back plate;

[0108] (6) The rough alloy back plate is leveled and turned in sequence, so that the flatness of the rough alloy back plate is ≤0.2 μm, the surface roughness is 0.7 μm, and a groove 3 is formed on its welding surface 2 to obtain a copper-zinc alloy back plate 1.

[0109] The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment both have a uniform organizational structure.

[0110] Example 5

[0111] This embodiment provides a method for preparing a copper-zinc alloy backplane, comprising the following steps:

[0112] (1) The materials are prepared according to the mass percentage of the metal components of 62wt% copper, 1.0wt% tin, and the balance of zinc, and are placed in a continuous casting furnace, and medium frequency induction melting is adopted. After the metal is fully melted, it is continuously cast into a rod-shaped billet;

[0113] (2) placing a rod-shaped billet with an aspect ratio of 1:1 in a box-type resistance furnace for preheating treatment at a temperature of 850° C. After reaching the preheating temperature, the rod-shaped billet is subjected to three consecutive forging treatments using an air hammer. The first time, the rod-shaped billet is stretched to 160% of the initial length and then roughened to the initial length. The second time, the rod-shaped billet is stretched to 150% of the initial length and then roughened to the initial length. The third time, the rod-shaped billet is stretched to 140% of the initial length and then roughened to the initial length to obtain an intermediate ingot having a thickness of 3 / 5 of the initial thickness of the rod-shaped billet, which is then air-cooled.

[0114] (3) The intermediate ingot is subjected to a heat treatment at 500°C for 3 hours, followed by water cooling;

[0115] (4) The intermediate ingot is subjected to a calendering treatment, and the calendering rate is 15%;

[0116] (5) performing a second-stage heat treatment on the intermediate ingot after the rolling treatment at a temperature of 350° C. with a holding time of 15 min, and then water cooling to obtain a rough alloy back plate;

[0117] (6) The rough alloy back plate is leveled and turned in sequence, so that the flatness of the rough alloy back plate is ≤0.2 μm, the surface roughness is 0.6 μm, and a groove 3 is formed on its welding surface 2 to obtain a copper-zinc alloy back plate 1.

[0118] The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment both have a uniform organizational structure.

[0119] Example 6

[0120] This embodiment provides a method for preparing a copper-zinc alloy back plate, which differs from Embodiment 1 in that: in step (1), the metal components are prepared according to the mass percentage of 70wt% copper, 1.0wt% tin, and the remainder zinc, and the other process parameters are the same as those of Embodiment 1. The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment have a uniform organizational structure.

[0121] Example 7

[0122] This embodiment provides a method for preparing a copper-zinc alloy back plate, which differs from Embodiment 1 in that: in step (1), the metal components are prepared according to the mass percentage of 50wt% copper, 1.0wt% tin, and the remainder zinc, and the other process parameters are the same as those of Embodiment 1. The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment have a uniform organizational structure.

[0123] Example 8

[0124] This embodiment provides a method for preparing a copper-zinc alloy back plate, which differs from Embodiment 1 in that: in step (2), during the three-repeated continuous forging process, the length of each stretching is the same, and the stretching is to 160% of the initial length, and the other process parameters are the same as those of Embodiment 1. The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment have a uniform organizational structure.

[0125] Example 9

[0126] This embodiment provides a method for preparing a copper-zinc alloy back plate, which is different from Embodiment 1 in that: in step (2), during the three-repeated continuous forging process, the rod-shaped blank is stretched to 130% of the initial length for the first time and then roughened to the initial length, the rod-shaped blank is stretched to 120% of the initial length for the second time and then roughened to the initial length, and the rod-shaped blank is stretched to 110% of the initial length for the third time and then roughened to the initial length, and the other process parameters are the same as those of Embodiment 1. The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment have a uniform organizational structure.

[0127] Example 10

[0128] This embodiment provides a method for preparing a copper-zinc alloy back plate, which is different from Embodiment 1 in that: in step (2), during the three-repeated continuous forging process, the rod-shaped blank is stretched to 200% of the initial length for the first time and then roughened to the initial length, the rod-shaped blank is stretched to 180% of the initial length for the second time and then roughened to the initial length, and the rod-shaped blank is stretched to 170% of the initial length for the third time and then roughened to the initial length, and the other process parameters are the same as those of Embodiment 1. The outer surface of the copper-zinc alloy back plate 1 and the cross section of the groove 3 obtained in this embodiment have a uniform organizational structure.

[0129] (1) The copper-zinc alloy back plate 1 obtained in Examples 1 to 10 was subjected to performance tests, and its hardness (GB / T7997-2014), electrical conductivity (GB / T35392-2017) and average grain size (GB / T6394-2017) were respectively tested. The results are shown in Table 1.

[0130] (2) In the present invention, the copper-zinc alloy back plate 1 obtained in Examples 1 to 10 and the high-purity titanium target blank are cleaned and assembled respectively, and then welded by hot isostatic pressing, and the welding bonding rate is tested. The results are shown in Table 1.

[0131] Table 1

[0132]

[0133]

[0134] As can be seen from Table 1, the copper-zinc alloy back plate 1 obtained in Examples 1 to 10 of the present application has a relatively low average grain size and a high welding bonding rate, which meets the use requirements of high-purity titanium sputtering targets. Comparing Example 1 with Example 6, it is not difficult to see that the welding bonding rate of Example 6 is reduced, mainly because the copper component content in the blank is too high and the zinc component content is reduced, which makes the hardness of the back plate insufficient, resulting in deformation during the welding process, reducing the welding pass rate. As can be seen from Example 1 and Example 7, the welding bonding rate of Example 7 is reduced, mainly because the copper component content in the blank is too low, which makes the hardness of the back plate too large, increasing the difficulty of welding.

[0135] It is not difficult to see from Table 1 that the average grain size of the copper-zinc alloy back plate 1 obtained in Example 1 is lower than that in Example 8. This is mainly because the length of each elongation of the billet of Example 1 is different during the three-time continuous forging process, showing a decreasing change. The deformation amount of the previous forging is greater than the deformation amount of the next forging, which makes the internal combination of the billet evenly broken, which is beneficial to reducing the grain size.

[0136] Compared with Example 1, the hardness and conductivity of the copper-zinc alloy back plate 1 obtained in Example 9 are reduced. This is mainly because the billet of Example 9 is stretched to a greater length than that of Example 1 during three repeated continuous forging processes, resulting in excessive deformation of the billet and reduced physical properties.

[0137] Compared with Example 1, the hardness and conductivity of the copper-zinc alloy back plate 1 obtained in Example 10 are all reduced, but the average grain size and the like are improved. This is mainly because the drawing length of the billet of Example 10 is smaller than that of Example 1 during the three-time continuous forging treatment, resulting in insufficient forging deformation of the billet and inability to completely crush the internal structure of the billet, causing the internal structure to be too large, affecting its performance.

[0138] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope 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 shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a copper-zinc alloy back plate for a titanium sputtering target, characterized in that: The preparation method comprises: (I) Providing copper-zinc alloy billets; (II) subjecting the blank to at least one hot forging treatment to obtain an intermediate ingot; The hot forging treatment comprises: sequentially performing a preheating treatment and at least one continuous forging treatment on the blank; The continuous forging process is carried out in the following manner: the blank is stretched to 130-160% of the initial length, and then roughened to the initial length; The continuous forging process is repeated at least three times, and the lengths of the elongation in two adjacent continuous forging processes decrease successively; (III) sequentially subjecting the intermediate ingot to a first-stage heat treatment, a rolling treatment, and a second-stage heat treatment to obtain a rough alloy back plate; The copper-zinc alloy blank comprises components of: 59-62wt% copper, 0.5-1.0wt% tin, and the balance is zinc.

2. The preparation method according to claim 1, characterized in that: In step (I), the method for preparing the blank comprises: After being mixed according to the mass percentage of the metal components, the materials are placed in a continuous casting furnace and smelted by medium frequency induction. After the metal is fully melted, it is continuously cast into a rod-shaped billet.

3. The preparation method according to claim 2, characterized in that: The aspect ratio of the rod-shaped blank is 1:(0.8-1.5).

4. The preparation method according to claim 1, characterized in that: The temperature of the preheating treatment is 700-850°C.

5. The preparation method according to claim 1, characterized in that: The blank is placed in a resistance furnace for preheating.

6. The preparation method according to claim 1, characterized in that: The blank is continuously forged by using an air hammer.

7. The preparation method according to claim 1, characterized in that: The thickness of the intermediate ingot is 1 / 2 to 2 / 3 of the initial thickness of the blank.

8. The preparation method according to claim 1, characterized in that: The preparation method further includes: after the hot forging treatment, performing a first cooling treatment on the intermediate ingot.

9. The preparation method according to claim 8, characterized in that: The first cooling process includes air cooling.

10. The preparation method according to claim 1, characterized in that: In step (III), the temperature of the heat treatment is 300-500°C.

11. The preparation method according to claim 1, characterized in that: The heat treatment time is 3 to 6 hours.

12. The preparation method according to claim 1, characterized in that: The preparation method further comprises: performing a second cooling treatment after the first stage of heat treatment.

13. The preparation method according to claim 12, characterized in that: The second cooling process includes water cooling.

14. The preparation method according to claim 1, characterized in that: The calendering rate of the calendering treatment is 10 to 20%.

15. The preparation method according to claim 1, characterized in that: The temperature of the second stage heat treatment is 300-350°C.

16. The preparation method according to claim 1, characterized in that: The time of the second stage heat treatment is 15 to 30 minutes.

17. The preparation method according to claim 1, characterized in that: The preparation method further comprises: performing a third cooling treatment after the second stage heat treatment.

18. The preparation method according to claim 17, characterized in that: The third cooling process includes water cooling.

19. The preparation method according to claim 1, characterized in that: The preparation method further comprises: leveling and machining the rough alloy back plate in sequence, so that the flatness of the rough alloy back plate is ≤0.2 μm and the roughness is 0.5-1.0 μm, to obtain a copper-zinc alloy back plate.

20. A copper-zinc alloy back plate, characterized in that: The copper-zinc alloy back plate is prepared by the preparation method described in any one of claims 1-19.

21. An application of the copper-zinc alloy back plate according to claim 20, characterized in that: The copper-zinc alloy back plate is used for titanium sputtering target material.

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