A method for manufacturing a silver alloy tube target

Abstract

The invention discloses a method for manufacturing a silver alloy tube target. The manufacturing method is specifically as follows: first, 90 parts of silver ingots and 10 parts of low-melting-point pure metal ingots are placed in an induction melting furnace for primary melting to obtain a silver alloy ingot A; wherein the low-melting-point pure metal ingot is an indium ingot, a tin ingot or a gallium ingot; then, the silver ingot and the silver alloy ingot A are weighed according to a mass ratio of (9-20):1, and placed in an induction melting furnace for secondary melting to obtain a silver alloy ingot B; the silver alloy ingot B is trimmed and hot-forged into a cylindrical ingot blank of a certain size; then, the cylindrical ingot blank is subjected to oblique rolling and perforation operations to obtain a silver alloy rough tube; then, the silver alloy rough tube is subjected to fine rolling, shaping, annealing and straightening operations to obtain a silver alloy tube blank; finally, the silver alloy tube blank is subjected to grinding machine processing to obtain a silver alloy tube target. The process steps are simple and the production efficiency is high. The purity, relative density and grain size of the prepared silver alloy tube target material all meet the use requirements of AMOLED display.

Description

Technical Field

[0001] The invention relates to the field of metal tube targets, in particular to a method for manufacturing a silver alloy tube target. Background Art

[0002] Metallic silver has the characteristics of high conductivity, high reflectivity to visible light, and good chemical stability, and can be used in AMOLED display panels as a reflective anode layer. However, pure silver has shortcomings such as poor Ag ion migration and corrosion resistance when used as a film layer. The use of pure silver materials will cause the performance of AMOLED devices to decay at a faster rate. In order to improve the shortcomings of pure Ag film layers, it is necessary to develop silver alloy materials that meet the requirements. Silver alloy target is the key material for making silver alloy film layers, and a magnetron sputtering process is used to prepare silver alloy metal film layers of appropriate thickness.

[0003] Currently, the widely used silver alloy targets are mainly planar targets. However, the magnetic field distribution of the planar target magnetron sputtering equipment is uneven, and the sputtering rates of different areas of the target are different during the sputtering process, resulting in a low material utilization rate of the planar target, with an average utilization rate of less than 35%. In addition, the silver alloy material is expensive, resulting in a high actual use cost of the silver alloy target. In contrast, the tubular target rotates at a constant speed during the sputtering process, and the surface of the target is evenly sputtered, so the actual utilization rate of the material can reach more than 80%, which has obvious advantages over the planar target.

[0004] The currently reported preparation methods of silver tube targets or silver alloy tube targets mainly include casting method, spraying method, etc. However, the density of silver tube targets prepared by these methods is low, and the grain size is difficult to control, which makes it difficult to meet the use requirements of high-end AMOLED display technology. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the present invention provides a method for manufacturing a silver alloy tube target. The process steps are simple and the production efficiency is high. The purity, relative density and grain size of the prepared silver alloy tube target material meet the use requirements of AMOLED display.

[0006] In order to achieve the above object, the specific scheme adopted by the present invention is:

[0007] A method for manufacturing a silver alloy tube target mainly comprises the following steps:

[0008] Step 1: Place 90 parts of silver ingots and 10 parts of low-melting-point pure metal ingots in an induction melting furnace for one smelting to obtain silver alloy ingot A; wherein the low-melting-point pure metal ingot is an indium ingot, a tin ingot or a gallium ingot;

[0009] Step 2, weighing the silver ingot and the silver alloy ingot A obtained in step 1 according to a mass ratio of (9-20):1, placing them in an induction melting furnace for secondary melting to obtain a silver alloy ingot B;

[0010] Step 3: shaping the silver alloy ingot B obtained in step 2, and then hot forging it into a cylindrical ingot of a certain size;

[0011] Step 4: performing oblique rolling and punching operations on the cylindrical ingot obtained in step 3 to obtain a silver alloy rough tube;

[0012] Step 5, performing finish rolling, shaping, annealing and straightening operations on the silver alloy rough tube obtained in step 4 to obtain a silver alloy tube blank;

[0013] Step 6: Grinding the silver alloy tube blank to obtain the final silver alloy tube target.

[0014] Furthermore, in step 1, the purity of the silver ingot and the low-melting-point pure metal ingot are both 4N.

[0015] Furthermore, in step 1 or step 2, the crucible used for induction melting is a graphite crucible, a magnesium oxide crucible or a high-purity corundum crucible, and before melting, the induction melting furnace is pre-evacuated to a pressure less than 1 Pa, and then argon gas is passed as a protective atmosphere.

[0016] Furthermore, the primary smelting temperature is 1100-1300°C.

[0017] Furthermore, the temperature of the secondary smelting is 1100-1300°C.

[0018] Furthermore, in step three, the silver alloy ingot B is first heated to 400-800° C., and then the silver alloy ingot B is die-forged into a cylindrical ingot with an outer diameter of 120 mm-150 mm by a hydraulic forging machine, and then cooled naturally.

[0019] Furthermore, in step four, the cylindrical ingot is first heated to 400~800℃ and then taken out, and then the cylindrical ingot is perforated with a perforating plug on a two-roll oblique rolling Mannheim perforating equipment to obtain a silver alloy rough tube; the outer diameter of the silver alloy rough tube is 140mm~180mm, and the inner diameter is 110mm~150mm.

[0020] Furthermore, the perforating plug material used is pure molybdenum, TZM molybdenum alloy or nickel-based high-temperature alloy.

[0021] Furthermore, in step five, finish rolling and shaping are performed on a tube rolling device at room temperature, and the outer diameter of the silver alloy tube blank after finish rolling is 130-170 mm, and the inner diameter is 110-140 mm.

[0022] Furthermore, in step five, the annealing temperature is 400-800° C., the holding time is 0.5-2 h, and then straightening is performed on a dedicated tube target straightening device.

[0023] Beneficial effects:

[0024] 1) The present invention improves the performance of silver alloy targets by alloying low-melting-point pure metals (indium or tin or gallium) to solve the problem of long-term performance degradation of pure silver targets. Due to the large differences in physical properties such as melting point and density between low-melting-point pure metals and silver metals, it is difficult to obtain uniform alloys using conventional smelting methods. The present invention adopts a method of first smelting and alloying, and then a second smelting, which can effectively avoid the problem of silver alloy components being difficult to uniformly dissolve. The prepared silver alloy tube target has good component uniformity and can meet the use requirements of high-performance AMOLED display devices.

[0025] 2) The present invention adopts the forming method of "forging + oblique rolling piercing + rolling", which has simple process steps and can directly make a tube of suitable thickness from a solid rod billet, with a high production yield. The forming process has a large deformation amount, and the prepared silver alloy tube target has fine grains and high density. Compared with the casting, spraying and other processes used in the prior art, the performance is significantly improved.

[0026] 3) Compared with the traditional extrusion perforation, the present invention adopts two-roller Mann oblique rolling perforation forming, which has good centering, uniform tube wall thickness, uniform organizational structure, and is conducive to improving the performance of silver alloy tube targets. At the same time, the production efficiency is significantly improved, which is more convenient for mass production. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] The present invention provides a method for manufacturing a silver alloy tube target, which mainly comprises the following steps:

[0029] Step 1: Select 90 parts of silver ingots with a purity of 4N and 10 parts of low-melting-point pure metal ingots with a purity of 4N, place them in a small medium-frequency induction heating melting furnace, first pre-evacuate to a pressure of less than 1Pa, then pass argon gas as a protective atmosphere, heat to 1100-1300°C for a smelting, and obtain a silver alloy ingot A; wherein the low-melting-point pure metal ingot is an indium ingot, a tin ingot or a gallium ingot;

[0030] Step 2: Place the silver alloy ingot A obtained in step 1 and the silver ingot with a weight of 9 to 20 times the weight in a large medium frequency induction heating melting furnace again, first pre-evacuate to a pressure of less than 1 Pa, then pass argon as a protective atmosphere, heat to 1100 to 1300° C. for secondary melting, and obtain silver alloy ingot B;

[0031] Step 3, shaping the silver alloy ingot B obtained in step 2, then heating the silver alloy ingot B to 400-800° C., and then forging it into a cylindrical ingot with an outer diameter of 120 mm-150 mm using a hydraulic forging machine, and cooling it naturally;

[0032] Step 4: first heat the cylindrical silver alloy ingot to 400-800°C and then take it out, and perforate it with a perforating plug on a two-roller oblique rolling Mannheim perforating device to obtain a silver alloy rough tube, the outer diameter of the rough tube blank is 140mm-180mm, and the inner diameter is 110mm-150mm;

[0033] Step 5: The silver alloy rough tube obtained in step 4 is finely rolled and shaped on a tube rolling device at room temperature. The outer diameter of the finely rolled silver alloy tube blank is 130-170 mm and the inner diameter is 110-140 mm. Then, annealing is performed at a temperature of 400-800°C, and then straightening is performed on a dedicated tube target straightening device to obtain a silver alloy tube blank;

[0034] Step 6: Perform further grinding processing according to the final drawing size to obtain the final silver alloy tube target.

[0035] In detail, in step 1 and step 2, the crucible used for medium frequency induction melting is a graphite crucible, magnesium oxide or high-purity corundum crucible.

[0036] In step 4, the material of the punching head used is pure molybdenum, TZM molybdenum alloy or nickel-based high-temperature alloy.

[0037] The technical solution of the present invention is described in detail below in conjunction with specific embodiments.

[0038] Example 1

[0039] This embodiment discloses a method for manufacturing a silver alloy tube target, which mainly includes the following steps:

[0040] Step 1: Take 9 parts of 4N purity silver ingots and 1 part of 4N purity indium ingot, place them in a small high-purity graphite crucible with a capacity of 5L, pre-evacuate to a pressure less than 1Pa, then pass argon as a protective atmosphere, heat to 1100°C for a smelting, and obtain silver alloy ingot A;

[0041] Step 2: Place the silver alloy ingot A obtained in step 1 and the silver ingot of 9 times the weight in step 1 in a large high-purity graphite crucible with a capacity of 50 L, pre-evacuate to a pressure of less than 1 Pa, then pass argon as a protective atmosphere, heat to 1100° C. for secondary smelting to obtain silver alloy ingot B;

[0042] Step 3: Heat the silver alloy ingot B to 700° C., forge it into a cylindrical ingot with an outer diameter of 140 mm using a hydraulic forging machine, and cool it naturally;

[0043] Step 4: first heat the cylindrical ingot obtained in step 3 to 700° C. and take it out, and perforate it with a nickel-based high-temperature alloy perforating plug on a two-roller oblique rolling Mannheim perforating device to obtain a silver alloy rough tube with an outer diameter of 160 mm and an inner diameter of 130 mm;

[0044] Step 5: The silver alloy rough tube obtained in step 4 is finely rolled and shaped at room temperature on a tube rolling device, and then annealed at 600° C. and kept warm for 1 hour; thereafter, it is straightened on a dedicated tube target straightening device to obtain a silver alloy tube blank with an outer diameter of 150 mm and an inner diameter of 125 mm;

[0045] Step 6: The silver alloy tube blank obtained in step 5 is further processed by a grinding machine to obtain a silver alloy tube target of a target size.

[0046] The silver alloy tube target prepared in this embodiment was sampled at both ends for density, metallographic, and ICP composition testing. The relative density was ≥99.5%, the average grain size was 45-50 μm, and the In content was 1.0±0.05wt%.

[0047] Example 2

[0048] This embodiment discloses a method for manufacturing a silver alloy tube target, which mainly includes the following steps:

[0049] Step 1: Take 9 parts of 4N purity silver ingots and 1 part of 4N purity gallium ingot, place them in a small high-purity graphite crucible with a capacity of 5L, pre-evacuate to a pressure less than 1Pa, then pass argon as a protective atmosphere, heat to 1150°C for a smelting, and obtain silver alloy ingot A;

[0050] Step 2: Place the silver alloy ingot A obtained in step 1 and the silver ingot 16 times its weight in a large high-purity graphite crucible with a capacity of 50 L again, pre-evacuate to a pressure of less than 1 Pa, then pass argon as a protective atmosphere, heat to 1150° C. for secondary smelting to obtain a silver alloy ingot B;

[0051] Step 3: Heat the silver alloy ingot B to 600° C., forge it into a cylindrical ingot with an outer diameter of 135 mm using a hydraulic forging machine, and cool it naturally;

[0052] Step 4: first heat the cylindrical ingot obtained in step 3 to 600°C and take it out, then perforate it with a nickel-based high-temperature alloy perforating plug on a two-roller oblique rolling Mannheim perforating device to obtain a silver alloy rough tube with an outer diameter of 155 mm and an inner diameter of 125 mm;

[0053] Step 5: The silver alloy rough tube of step 4 is finely rolled and shaped at room temperature on a tube rolling device, and then annealed at 500° C. and kept warm for 1 hour; thereafter, it is straightened on a dedicated tube target straightening device to obtain a silver alloy tube blank with an outer diameter of 148 mm and an inner diameter of 120 mm;

[0054] Step 6: The silver alloy tube blank of step 5 is further processed by a grinding machine to obtain a silver alloy tube target of a target size.

[0055] Samples were taken from both ends of the silver alloy tube target prepared in this embodiment for density, metallographic, and ICP composition testing. The relative density was ≥99.5%, the average grain size was 40-45 μm, and the Ga content was 0.63±0.05 wt%.

[0056] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Any equivalent changes or modifications made according to the essence of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a silver alloy tube target, characterized in that: The main steps are as follows: Step 1: Place 90 parts of silver ingots and 10 parts of low-melting-point pure metal ingots in an induction melting furnace for primary melting at a temperature of 1100-1300° C. to obtain silver alloy ingot A; wherein the low-melting-point pure metal ingot is an indium ingot, a tin ingot or a gallium ingot; Step 2, weighing the silver ingot and the silver alloy ingot A obtained in step 1 according to a mass ratio of (9-20):1, placing them in an induction melting furnace for secondary melting at a temperature of 1100-1300° C., and obtaining a silver alloy ingot B; Step 3: shaping the silver alloy ingot B obtained in step 2, and then hot forging it into a cylindrical ingot of a certain size; Step 4: performing oblique rolling and punching operations on the cylindrical ingot obtained in step 3 to obtain a silver alloy rough tube; Step 5, performing finish rolling, shaping, annealing and straightening operations on the silver alloy rough tube obtained in step 4 to obtain a silver alloy tube blank; Step 6: Grinding the silver alloy tube blank to obtain the final silver alloy tube target.

2. The method for manufacturing a silver alloy tube target according to claim 1, characterized in that: In step 1, the purity of the silver ingot and the low melting point pure metal ingot are both 4N.

3. The method for manufacturing a silver alloy tube target according to claim 1, characterized in that: In step 1 or step 2, the crucible used for induction melting is a graphite crucible, a magnesium oxide crucible or a high-purity corundum crucible. Before melting, the induction melting furnace is pre-evacuated to a pressure less than 1 Pa, and then argon gas is passed as a protective atmosphere.

4. The method for manufacturing a silver alloy tube target according to claim 1, characterized in that: In step three, the silver alloy ingot B is first heated to 400-800° C., and then the silver alloy ingot B is die-forged into a cylindrical ingot with an outer diameter of 120 mm-150 mm by a hydraulic forging machine, and then cooled naturally.

5. The method for manufacturing a silver alloy tube target according to claim 4, characterized in that: In step 4, the cylindrical ingot is first heated to 400-800°C and then taken out, and then the cylindrical ingot is perforated with a perforating head on a two-roll oblique rolling Mannheim perforating device to obtain a silver alloy rough tube; the outer diameter of the silver alloy rough tube is 140mm-180mm, and the inner diameter is 110mm-150mm.

6. The method for manufacturing a silver alloy tube target according to claim 5, characterized in that: The material of the piercing plug used is pure molybdenum, TZM molybdenum alloy or nickel-based high-temperature alloy.

7. The method for manufacturing a silver alloy tube target according to claim 5, characterized in that: In step 5, the finish rolling and shaping is carried out on the tube rolling equipment at room temperature. After the finish rolling, the outer diameter of the silver alloy tube blank is 130-170 mm, and the inner diameter is 110-140 mm.

8. The method for manufacturing a silver alloy tube target according to claim 1, characterized in that: In step five, the annealing temperature is 400-800°C, the holding time is 0.5-2h, and then the target is straightened on a tube straightening device.