A method of manufacturing a ring-shaped brass backplate

Abstract

The present application relates to alloy back plate preparation technical field, specifically relates to a kind of preparation method of annular brass back plate, comprising the following steps: S1, hot extrusion;S2, first heat forging;S3, first heat treatment;S4, second heat forging and roll ring;S5, second heat treatment;The preparation method of the present application is hot extruded before blank forging, can improve the surface quality of raw material, prevent crack in the forging process;Multiple upsetting and drawing are carried out in the forging process, which can reduce internal coarse grains and unevenness;Under the shaping process of second forging and roll ring, it can guarantee smaller machining allowance, improve material utilization.

Description

Technical Field

[0001] This invention relates to the field of alloy backplate preparation technology, specifically to a method for preparing an annular brass backplate. Background Technology

[0002] The target backplate is a crucial component of sputtering targets, primarily used to fix the sputtered target material and ensure its stability during sputtering. The target backplate needs to provide the necessary electrical and thermal conductivity to ensure target stability and uniform film deposition during sputtering. During sputtering, high-energy ions continuously bombard the target surface, generating a significant amount of heat. The backplate enhances heat conduction, preventing overheating and maintaining target temperature stability. In magnetron sputtering deposition, the target must simultaneously withstand the cooling water pressure on the back side and the vacuum negative pressure on the front side; therefore, the target backplate is particularly important.

[0003] CN110871234A provides a method for processing and forming an annular backplate. The method includes: heating a cylindrical ingot and then performing a blanking process, followed by punching and ring rolling to form an annular backplate. However, the target backplate mentioned in this invention is made of aluminum alloy, and the large deformation ring rolling process can easily lead to grain anisotropy, which may result in uneven internal structure of the brass ring and dezincification. Therefore, this method is not suitable for the preparation of brass annular backplates.

[0004] The common manufacturing process for copper alloy ring back plates is "hot forging - heat treatment - machining". Hot forging can either forge a solid billet and then bore it, or forge it into a hollow cylinder and then turn it. However, both processes currently suffer from large machining allowances and low material utilization.

[0005] In conclusion, for the preparation of annular brass backplates, it is necessary to select appropriate process methods that can save materials and obtain backplates with uniform structure and high purity. Summary of the Invention

[0006] To address the above problems, the present invention provides a method for preparing an annular brass back plate.

[0007] A method for preparing an annular brass back plate includes the following steps:

[0008] S1. Hot extrusion:

[0009] The brass alloy ingot is heated to 830-870℃ within 80-100 minutes and held for 30-80 minutes. It is then hot-extruded with a deformation amount of 35-45%. The hot-extruded ingot is then immersed in water at a temperature of 25-40℃ for online solution treatment for 5-10 minutes to obtain the hot-extruded billet.

[0010] S2, One-time hot forging:

[0011] The hot extruded billet obtained in S1 is heated to 790-830℃ within 60-80 minutes and held at that temperature for 30-60 minutes. Then, a 1-ton air hammer is used to perform a first upsetting, drawing, second upsetting, punching, reaming, and flattening process on the hot extruded billet. The forging ratio of the first upsetting and second upsetting is 1.4-1.6:1, and the drawing forging ratio is 1.1-1.3:1, to obtain a ring.

[0012] S3, First heat treatment:

[0013] The ring obtained in S2 is subjected to a heat treatment.

[0014] S4, Secondary Hot Forging and Ring Rolling:

[0015] The ring obtained after the first heat treatment of S3 is heated to 790-830℃ within 60-80 minutes and held for 30-60 minutes. Then, a 1-ton air hammer is used to perform plane-hole-plane-plane-after-planarization. After completion, the ring is rolled to the required size, and the ring temperature is kept at 700-750℃ during rolling.

[0016] S5, Secondary heat treatment:

[0017] Finally, the ring obtained by S4 ring rolling is subjected to secondary heat treatment and machining to complete the preparation.

[0018] Furthermore, the composition of the brass alloy ingot, by mass percentage, includes: Cu: 62-64%; Pb ≤ 0.08%; Fe ≤ 0.05%; Ni ≤ 0.01%; Zn: balance.

[0019] Note: The brass alloys with the above composition have good mechanical properties, excellent processing performance, good electrical and thermal conductivity, as well as corrosion resistance and oxidation resistance.

[0020] Furthermore, in S3, the heating time for the first heat treatment is 25-35 minutes, the heating temperature is 240-300°C, and the holding time is 60-80 minutes.

[0021] Note: The above heat treatment parameters can effectively reduce residual stress in materials and prevent cracks from forming.

[0022] Furthermore, in S4, the heating time for the secondary heat treatment is 25-35 minutes, the heating temperature is 240-300°C, and the holding time is 60-80 minutes.

[0023] Note: The above heat treatment parameters can effectively reduce residual stress in materials and prevent cracks from forming.

[0024] Furthermore, the machining process includes rough turning and finish turning.

[0025] Note: Roughing and finishing can work together to improve machining efficiency, save costs, improve machining quality, and reduce error accumulation.

[0026] Furthermore, after the ring is rolled out and before the secondary heat treatment, the inner ring surface of the ring is first toughened. The toughening treatment method is as follows:

[0027] The entire surface of the ring is covered with a mask, and the inner ring surface of the ring is divided into an upper part, a middle part, and a lower part from top to bottom. The upper part occupies 1 / 5 to 3 / 5 of the height of the ring, and the lower part occupies 1 / 10 to 1 / 5 of the height of the ring.

[0028] The mask located on the inner ring surface has multiple holes with a diameter of 0.1 to 0.5 mm. The total surface area of ​​the multiple holes accounts for 70 to 90% of the surface area of ​​the inner ring surface. The hole density in the upper part is 40 to 50% of the total hole density, and the hole density in the lower part is 30 to 40% of the total hole density.

[0029] The ring is then immersed in an etching solution at a temperature of 35–55°C for 5–10 minutes. After etching, the etching solution is washed away and the ring is dried. Then, the inner ring surface is shot-peened with shot with a diameter of 1–3 mm. The ultrasonic shot-peening device has a vibration frequency of 50–60 Hz, an amplitude of 25–30 μm, a shot-peening time of 3–5 minutes, and a shot-peening distance of 15–20 mm. The toughening treatment is then complete.

[0030] Explanation: By etching with holes of varying densities on the inner surface of the ring, more etching holes at the upper end effectively disperse the residual stress after punching. Simultaneously, they rapidly absorb and dissipate energy under initial stress, improving the ring's impact resistance. Fewer etching holes in the middle section ensure the ring's strength and rigidity to some extent, preventing excessive strength loss due to excessive etching, thus playing a crucial role in bridging the upper and lower sections. Adding more etching holes at the lower end further disperses stress at the bottom of the ring and works better with the compressive stress generated by shot peening, improving the overall toughness and fatigue resistance of the ring. Shot peening further improves surface quality; the impact of the shot causes a certain degree of plastic deformation on the inner ring surface, forming residual compressive stress. For the brass target material, this residual compressive stress helps improve the target material's fatigue resistance and deformation resistance during use.

[0031] Furthermore, the etching solution comprises, by mass, 10-15 parts of ferric chloride solution with a mass concentration of 35-38% and 1-2 parts of tetraethylammonium chloride solution with a purity of 80-85%.

[0032] Note: The ferric chloride solution and tetraethylammonium chloride solution in the etching solution will chemically react with the brass alloy, removing some impurities and defects on the surface, making the surface purer, and forming a microstructure that is conducive to electron transport and has a positive effect on electrical conductivity.

[0033] Compared with existing methods for preparing annular brass back plates, the advantages of this invention are:

[0034] (1) The preparation method of the present invention performs hot extrusion on the billet before forging, which can improve the surface quality of the raw material and prevent cracks from appearing during the forging process; multiple upsetting and drawing are performed during the forging process, which can reduce the internal coarse grains and inhomogeneity; under the shaping process of secondary forging and ring rolling, a small machining allowance can be guaranteed and the material utilization rate can be improved.

[0035] (2) The preparation method of this invention involves etching with holes of different densities on the inner surface of the ring. More etching holes at the upper end effectively disperse the residual stress after punching, and simultaneously absorb and dissipate energy quickly under initial stress, improving the ring's impact resistance. Fewer etching holes in the middle section ensure the ring's strength and rigidity to a certain extent, preventing excessive strength loss due to excessive etching holes, thus playing a crucial role. An additional number of etching holes at the lower end further disperses stress at the bottom of the ring and works better with the compressive stress generated by shot peening, improving the overall toughness and fatigue resistance of the ring. Shot peening further improves surface quality; the impact of the shot causes a certain degree of plastic deformation on the inner surface, forming residual compressive stress. For the brass target material, this residual compressive stress helps improve the target material's fatigue resistance and deformation resistance during use. Attached Figure Description

[0036] Figure 1 This is a comparison chart of the results of Experiment Example 1 of this invention;

[0037] Figure 2 This is a comparison chart of the results of Experiment Example 2 of this invention. Detailed Implementation

[0038] To further illustrate the methods and effects of this invention, the technical solution of this invention will be clearly and completely described below in conjunction with experiments.

[0039] Example 1: A method for preparing an annular brass back plate, comprising the following steps:

[0040] S1. Hot extrusion:

[0041] The brass alloy ingot is heated to 850℃ within 90 minutes and held at that temperature for 55 minutes. It is then hot-extruded with a deformation rate of 40%. The hot-extruded ingot is then immersed in water at 30℃ for online solution treatment for 8 minutes to obtain a hot-extruded billet with a diameter of Ф120mm. The composition of the brass alloy ingot, by mass percentage, includes: Cu: 63%; Pb: 0.08%; Fe: 0.05%; Ni: 0.01%; Zn: balance.

[0042] S2, One-time hot forging:

[0043] The hot extruded billet with diameter Ф120*260mm obtained in S1 was heated to 810℃ within 70 minutes and held at that temperature for 45 minutes. Then, a 1-ton air hammer was used to perform a first upsetting, drawing, second upsetting, punching, reaming, and flattening process on the hot extruded billet. The forging ratio of the first upsetting and second upsetting was 1.5:1, and the drawing forging ratio was 1.2:1, resulting in a ring with diameter Ф259×Ф175×95mm.

[0044] S3, First heat treatment:

[0045] The ring obtained in S2 is subjected to a heat treatment for 30 minutes, at a temperature of 260°C, and for 70 minutes.

[0046] S4, Secondary Hot Forging and Ring Rolling:

[0047] The ring obtained after the first heat treatment of S3 was heated to 810℃ within 70 minutes and held for 45 minutes. Then, a 1-ton air hammer was used to perform a planarization-hole reaming-planarization process to obtain a ring with a diameter of Ф459×Ф410×82mm. After completion, the ring was rolled to a diameter of Ф465×Ф415×79mm, and the ring temperature was kept at 730℃ during the rolling process.

[0048] S5, Secondary heat treatment:

[0049] Finally, the ring obtained by S4 rolling is subjected to secondary heat treatment and machining. The secondary heat treatment is carried out for 30 minutes at a temperature of 260°C and held for 70 minutes. The machining is rough turning and finish turning. The preparation is then completed.

[0050] Example 2: The difference between this example and Example 1 is that the brass alloy ingot is heated to 830°C for 80 minutes, held for 30 minutes, and then hot-extruded with a deformation amount of 35%. The hot-extruded ingot is then immersed in water at a temperature of 25°C for online solution treatment for 5 minutes.

[0051] Example 3: The difference between this example and Example 1 is that the brass alloy ingot is heated to 870°C for 100 minutes, held for 80 minutes, and then hot-extruded with a deformation amount of 45%. The hot-extruded ingot is then immersed in water at 40°C for online solution treatment for 10 minutes.

[0052] Example 4: This example differs from Example 1 in that the composition of the brass alloy ingot is Cu: 62%.

[0053] Example 5: This example differs from Example 1 in that the composition of the brass alloy ingot is Cu: 64%.

[0054] Example 6: The difference between this example and Example 1 is that the hot extruded billet obtained in S1 is heated to 790°C within 60 minutes and held for 30 minutes.

[0055] Example 7: The difference between this example and Example 1 is that the hot extruded billet obtained in S1 is heated to 830°C within 80 minutes and held at that temperature for 60 minutes.

[0056] Example 8: The difference between this example and Example 1 is that the forging ratio of the first upsetting and the second upsetting is 1.4:1, and the drawing forging ratio is 1.1:1.

[0057] Example 9: The difference between this example and Example 1 is that the forging ratio of the first upsetting and the second upsetting is 1.6:1, and the drawing forging ratio is 1.3:1.

[0058] Example 10: The difference between this example and Example 1 is that the heating time for one heat treatment is 25 minutes, the heating temperature is 240°C, and the holding time is 60 minutes.

[0059] Example 11: The difference between this example and Example 1 is that the heating time for one heat treatment is 35 minutes, the heating temperature is 300°C, and the holding time is 80 minutes.

[0060] Example 12: The difference between this example and Example 1 is that the ring obtained after the first heat treatment of S3 is heated to 790°C within 60 minutes and held at that temperature for 30 minutes.

[0061] Example 13: The difference between this example and Example 1 is that the ring obtained after the first heat treatment of S3 is heated to 830°C within 80 minutes and held at that temperature for 60 minutes.

[0062] Example 14: The difference between this example and Example 1 is that the ring temperature is maintained at 700°C during the ring rolling process.

[0063] Example 15: The difference between this example and Example 1 is that the ring temperature is maintained at 750°C during the ring rolling process.

[0064] Example 16: The difference between this example and Example 1 is that the heating time for the secondary heat treatment is 25 minutes, the heating temperature is 240°C, and the holding time is 60 minutes.

[0065] Example 17: The difference between this example and Example 1 is that the heating time for the secondary heat treatment is 35 minutes, the heating temperature is 300°C, and the holding time is 80 minutes.

[0066] Example 18: This example differs from Example 1 in that, after the ring is rolled and before the secondary heat treatment, the inner ring surface of the ring is first toughened. The toughening method is as follows:

[0067] The entire surface of the ring is covered with a mask, and the inner ring surface of the ring is divided into an upper part, a middle part, and a lower part from top to bottom. The upper part occupies 1 / 4 of the height of the ring, and the lower part occupies 1 / 6 of the height of the ring.

[0068] The mask located on the inner ring surface has multiple holes with a diameter of 0.3 mm. The total surface area of ​​the multiple holes accounts for 80% of the surface area of ​​the inner ring surface. The hole density in the upper part is 45% of the total hole density, and the hole density in the lower part is 35% of the total hole density.

[0069] The ring is then completely immersed in an etching solution, which, by mass, comprises 12.5 parts of a 36% ferric chloride solution and 1.5 parts of a 83% tetraethylammonium chloride solution. The etching temperature is 42°C, and the etching time is 8 minutes. After etching, the etching solution is washed away and the ring is dried. Then, the inner ring surface is shot-peened with steel shot of 2 mm diameter. The vibration frequency of the shot-peening device is 55 Hz, the amplitude is 28 μm, the shot-peening time is 4 minutes, and the shot-peening distance is 18 mm. The toughening treatment is then completed.

[0070] Example 19: This example differs from Example 18 in that the upper part occupies 1 / 5 of the height of the ring, the lower part occupies 1 / 5 of the height of the ring, the diameter of the hole is 0.1mm, the total surface area of ​​the multiple holes accounts for 70% of the surface area of ​​the inner ring, the hole density in the upper part is 40% of the total hole density, and the hole density in the lower part is 30% of the total hole density.

[0071] Example 20: This example differs from Example 18 in that the upper part occupies 1 / 3 of the ring height, the lower part occupies 1 / 7 of the ring height, the diameter of the hole is 0.5mm, the total surface area of ​​the multiple holes accounts for 90% of the inner ring surface area, the hole density in the upper part is 50% of the total hole density, and the hole density in the lower part is 40% of the total hole density.

[0072] Example 21: This example differs from Example 18 in that the etching solution, by mass, includes 10 parts of ferric chloride solution with a mass concentration of 35% and 2 parts of tetraethylammonium chloride solution with a purity of 85%.

[0073] Example 22: This example differs from Example 18 in that the etching solution, by mass, includes 15 parts of ferric chloride solution with a mass concentration of 38% and 1 part of tetraethylammonium chloride solution with a purity of 80%.

[0074] Example 23: This example differs from Example 18 in that the etching temperature is 35°C and the etching time is 5 minutes.

[0075] Example 24: This example differs from Example 18 in that the etching temperature is 55°C and the etching time is 10 min.

[0076] Example 25: The difference between this example and Example 18 is that steel shot with a diameter of 1 mm is used to perform surface shot peening on the inner ring surface. The vibration frequency of the shot peening device is 50 Hz, the amplitude is 25 μm, the shot peening time is 3 min, and the shot peening distance is 15 mm.

[0077] Example 26: The difference between this example and Example 18 is that steel shot with a diameter of 3mm is used to perform surface shot peening on the inner ring surface. The vibration frequency of the shot peening device is 60Hz, the amplitude is 30μm, the shot peening time is 5min, and the shot peening distance is 20mm.

[0078] Experimental Example: The description of this experimental example is based on the scheme described in Example 1, and aims to illustrate the practical application effect of the present invention.

[0079] The electrical conductivity of the brass alloy backplates prepared in each embodiment of this application was investigated. The average value of five results for each embodiment was taken as the final test result.

[0080] 1. Investigate the influence of brass backing plate preparation parameters on the electrical conductivity of brass alloy backing plate.

[0081] Depend on Figure 1The results show that in Examples 1 to 17, excessively small or large hot extrusion parameters, excessively small or large copper content in the brass backing plate, excessively small or large heating parameters in the first hot forging, excessively small or large deformation parameters in the first hot forging, excessively small parameters in the first heat treatment, excessively small or large heating parameters in the second hot forging, excessively small or large rolling temperature, and excessively small parameters in the second heat treatment all reduce the electrical conductivity of the brass alloy backing plate. Examples 11 and 12 have higher heating temperatures and longer holding times in the heat treatment, which improves the electrical conductivity of the brass alloy backing plate to a certain extent compared with Example 1, but the improvement is relatively small compared with the improvement of the heat treatment parameters. Therefore, from an economic point of view, the parameter effect of Example 1 is relatively better.

[0082] 2. To investigate the effect of toughening treatment on the inner ring surface of the ring before secondary heat treatment on the fatigue resistance of the brass alloy back plate compared with Example 1.

[0083] The difference between Comparative Example 1 and Example 18 is that the pore density is the same in all parts of the inner ring surface of the ring member;

[0084] Depend on Figure 2 The results show that the electrical conductivity of Examples 18-26 and Comparative Example 1 is increased compared to that of Example 1. This indicates that the toughening treatment of this application improves the performance of Example 1. However, Comparative Example 1 lacks differentiation of the pore density of different parts of the ring, and the improvement is reduced compared to Examples 18-26. Therefore, distributing the pore density according to different parts of the inner ring surface is beneficial.

[0085] Furthermore, comparing Examples 18 to 26, it can be seen that if the hole density in the upper part is too small or too large, the proportion of tetraethylammonium chloride solution in the etching solution is too small or too large, the etching parameters are too small or too large, and the shot peening parameters are too small or too large, the improvement in the electrical conductivity of the brass backplate will be reduced. Therefore, in summary, the parameter effect of Example 18 is relatively better.

Claims

1. A method for preparing an annular brass back plate, characterized in that, Includes the following steps: S1. Hot extrusion: The brass alloy ingot is heated to 830-870℃ within 80-100 minutes and held for 30-80 minutes. It is then hot-extruded with a deformation amount of 35-45%. The hot-extruded ingot is then immersed in water at a temperature of 25-40℃ for online solution treatment for 5-10 minutes to obtain the hot-extruded billet. S2, One-time hot forging: The hot extruded billet obtained in S1 is heated to 790-830℃ within 60-80 minutes and held at that temperature for 30-60 minutes. Then, a 1-ton air hammer is used to perform a first upsetting, drawing, second upsetting, punching, reaming, and flattening process on the hot extruded billet. The forging ratio of the first upsetting and second upsetting is 1.4-1.6:1, and the drawing forging ratio is 1.1-1.3:1, to obtain the ring part. S3, First heat treatment: The ring obtained in S2 is subjected to a heat treatment. S4, Secondary Hot Forging and Ring Rolling: Heat the ring obtained after the first heat treatment of S3 to 790-830℃ within 60-80 minutes, hold for 30-60 minutes, and then use a 1-ton air hammer to perform plane-hole-plane-plane; after completion, roll the ring to the required size, keeping the ring temperature at 700-750℃ during rolling. S5, Secondary heat treatment: First, the inner ring surface of the ring component is toughened. The toughening method is as follows: The entire surface of the ring is covered with a mask, and the inner ring surface of the ring is divided into an upper part, a middle part, and a lower part from top to bottom. The upper part occupies 1 / 5 to 1 / 3 of the height of the ring, and the lower part occupies 1 / 7 to 1 / 5 of the height of the ring. The mask located on the inner annular surface has multiple holes with a diameter of 0.1~0.5mm. The total surface area of ​​the multiple holes accounts for 70~90% of the surface area of ​​the inner annular surface. The hole density in the upper part is 40~50% of the total hole density, and the hole density in the lower part is 30~40% of the total hole density. The ring is then immersed in the etching solution at a temperature of 35-55°C for 5-10 minutes. After etching, the etching solution is washed away and the ring is dried. The inner ring surface is then shot-peened with a vibration frequency of 50-60 Hz, an amplitude of 25-30 μm, a shot-peening time of 3-5 minutes, and a shot-peening distance of 15-20 mm. The toughening treatment is then completed. The etching solution, by mass, includes 10-15 parts of ferric chloride solution with a mass concentration of 35-38% and 1-2 parts of tetraethylammonium chloride solution with a purity of 80-85%. The toughened ring is then subjected to a second heat treatment and machining to complete the preparation.

2. The method for preparing an annular brass back plate as described in claim 1, characterized in that, The composition of the brass alloy ingot, by mass percentage, includes: Cu: 62~64%; Pb≤0.08%; Fe≤0.05%; Ni≤0.01%; Zn: balance.

3. The method for preparing an annular brass back plate as described in claim 1, characterized in that, In S3, the heating time for the first heat treatment is 25~35 min, the heating temperature is 240~300℃, and the holding time is 60~80 min.

4. The method for preparing an annular brass back plate as described in claim 1, characterized in that, In S5, the heating time for the secondary heat treatment is 25-35 minutes, the heating temperature is 240-300°C, and the holding time is 60-80 minutes.

5. The method for preparing an annular brass back plate as described in claim 1, characterized in that, The machining process includes rough turning and finish turning.

6. The method for preparing an annular brass back plate as described in claim 1, characterized in that, The surface shot peening uses steel shot with a diameter of 1-3 mm.

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