Preparation method and device of Al-Sc alloy plane target material with high Sc content

Abstract

The invention provides a preparation method of an Al-Sc alloy plane target material with high Sc content, which comprises the following steps: S1, for an alloy AlScX0 with a target component of AlScX0, adding raw materials Sc and Al into a water-cooled copper crucible according to the total Sc amount required by the AlScX0 alloy and the Al amount required by the component AlScX1; wherein X < 0 > is equal to 0.1-0.7, and X < 1 > gt; x0; s2, after Sc and Al in the water-cooled copper crucible are melted, Al is added into the water-cooled copper crucible, and alloy AlScX0 with the target component being AlScX0 is formed through smelting; and S3, after the smelting process is finished, alloy liquid in the water-cooled copper crucible is poured into a mold, when the molten liquid is in a semi-solidified state, an extrusion device is started to extrude materials in the semi-solidified state, and the Al-Sc alloy plane target material is formed. The invention provides two processes of firstly smelting the high-melting-point Sc-Al alloy and then adding Al into the high-melting-point Sc-Al alloy, so that a technical guarantee is provided for obtaining the Al-Sc alloy with accurate and uniform components; the extrusion casting technology enables the alloy in a semi-liquid state to be rapidly solidified under pressure, metallurgical defects of segregation, pores, cracks and the like in a blank are eliminated, and a structure with fine crystal grains can be formed.

Description

Technical Field

[0001] The invention belongs to the technical field of material preparation, and in particular relates to a method and a device for preparing an Al-Sc alloy planar target material with a high Sc content. Background Art

[0002] Al-Sc alloy with high Sc content is a newly developed high-end target alloy. In application technology, the so-called Al-Sc alloy with high Sc content refers to Al-Sc alloy with Sc content higher than 10at.% (equivalent to 15wt.%). High-end target materials have strict requirements on material purity, uniformity and grain size. Sc, as a rare earth element, has high activity. When Al-Sc alloy is melted by medium frequency induction melting technology, Sc will react strongly with the crucible material to increase the impurity content. For Al-Sc alloy with high Sc content, this problem is more serious. Therefore, suspension melting is an effective means to melt Al-Sc alloy with high Sc content.

[0003] However, the Al-Sc alloy cannot be successfully smelted by suspension melting using ordinary processes. This is related to the fact that the melting point of Al is 660°C, while the melting point of Sc is 1541°C, and the melting point difference between the two is very large. If the raw materials Al and Sc are mixed in a crucible according to the proportion of the alloy components for melting, Al will melt first to form a molten pool, and the high-melting-point Sc bubbles will hardly melt in the low-temperature molten pool; and suspension melting has a characteristic that once the material melts, it is difficult to increase the temperature again. Even if the power is greatly increased, the superheat is only more than 100 degrees. How to use suspension melting technology to obtain Al-Sc alloys with components that meet the requirements is an important technical problem to be solved by the present invention.

[0004] Alloy targets are mostly made from alloy ingots by hot working into target blanks that meet the requirements. However, Al-Sc alloys with high Sc content are very brittle and cannot be hot worked. Although the alloy liquid can be cast into target blanks according to the size requirements after smelting, the cast materials generally have defects such as component segregation, pores, cracks, etc., and the coarse grains do not meet the target material requirements for grain size. How to obtain a target blank that meets the requirements in shape, size and material after completing the smelting process is also an important technical problem to be solved by the present invention. Summary of the invention

[0005] In order to solve the problems mentioned in the background technology, the present invention aims at the difficulty that there is a large melting point difference between Al and Sc, and the high melting point Sc cannot be melted in the low temperature Al molten pool after the low melting point Al is melted. Two processes of first melting the high melting point Sc-Al alloy and then adding Al to the alloy are proposed, which provide technical guarantee for obtaining Al-Sc alloy with accurate and uniform composition. After pouring the alloy liquid in the crucible into the mold, the extrusion device installed on the equipment is used to apply pressure to the semi-liquid alloy in the mold, so that the material solidifies under pressure to form a blank of the target material; if necessary, the target blank can be heat processed by vacuum hot pressing.

[0006] The present invention provides a method for preparing an Al-Sc alloy planar target material with a high Sc content, comprising the following steps:

[0007] S1, for the target composition of AlSc X0 Alloy AlSc X0 , according to AlSc X0 The total amount of Sc required for the alloy and the composition of AlSc X1 Add the raw materials Sc and Al into a water-cooled copper crucible;

[0008] Among them, X0=0.1~0.7at., X1>X0;

[0009] S2. After Sc and Al in the water-cooled copper crucible are melted, Al is added to the water-cooled copper crucible to melt the target composition of AlSc. X0 Alloy AlSc X0 ;

[0010] S3. After the smelting process is completed, the alloy liquid in the water-cooled copper crucible is poured into the mold. When the molten liquid is in a semi-solidified state, the extrusion device is started to extrude the semi-solidified material to form an Al-Sc alloy flat target.

[0011] Further, step S2 includes the following steps:

[0012] S21, according to AlSc X0 Alloy with AlSc X1 The difference of Al required by the alloy is added to the feeder to add raw material Al;

[0013] S22. During the smelting of AlScX1 alloy, after Sc and Al in the water-cooled copper crucible are completely melted and alloyed, Al is added to the water-cooled copper crucible from the feeder in 2 to 5 times. After each addition of Al, wait until the added Al is completely melted and homogenized before adding Al again, until all the materials in the water-cooled copper crucible are melted, alloyed and completely homogenized to form AlScX1. X0 alloy.

[0014] Further, step S2 includes the following steps:

[0015] S21, in smelting AlSc X1 After the alloying process is completed, turn over the water-cooled copper crucible containing AlSc X1 Alloy ingots, and according to the composition AlSc X2 With AlSc X1 The difference in the amount of Al required is added to the water-cooled copper crucible;

[0016] S22, in smelting AlSc X2 After the alloying process is completed, the composition of the water-cooled copper crucible is turned over to be AlSc X2 The alloy ingot is then divided into two parts according to the composition of AlSc X3 With AlSc X2 Add Al to the water-cooled copper crucible according to the difference in the amount of Al required;

[0017] S23, and so on, until the composition is AlSc X0 Alloys;

[0018] Among them, X1>X2>X3>X0.

[0019] Furthermore, X1 is selected to be 0.65 to 0.7 at.

[0020] Furthermore, X1 is selected to be 0.65-0.7 at., and X2, X3, and X4 are selected near the composition of AlSc, Al2Sc, and Al3Sc.

[0021] Furthermore, after adding Al, the power needs to be increased for a period of time to ensure that the added Al is completely melted and the temperature of the molten pool rises;

[0022] And / or, the melting process requires increased power and stronger electromagnetic stirring.

[0023] Furthermore, in step S3, after the smelting process is completed, the alloy liquid in the water-cooled copper crucible is poured into the mold. After a residence time of 0.1 to 5 minutes, the extrusion device is started, and the piston rod drives the pressure rod to move downward, so that the pressure head is pressed into the mold to apply pressure P to the semi-solidified material, where P = 1 to 100 MPa;

[0024] The pressure state is maintained for a period of 0.2 to 50 minutes. When the casting blank is completely solidified, the piston rod is lifted to allow the pressure head to withdraw from the mold. When the blank is cooled, the vacuum melting chamber is opened to take out the blank.

[0025] The present invention also provides a preparation device for a planar target material of an Al-Sc alloy with a high Sc content, which is applied to the above-mentioned preparation method, and comprises a water-cooled copper crucible installed in a vacuum melting chamber, and an induction coil installed on the periphery of the water-cooled copper crucible is connected to an induction power supply outside the vacuum melting chamber through an electrode;

[0026] A mold is installed at the lower side of the water-cooled copper crucible, and the shape and diameter of the inner cavity thereof match the design requirements of the target blank;

[0027] The crucible tilting shaft penetrates the side wall of the vacuum melting chamber through a vacuum dynamic seal, and one end outside the vacuum melting chamber is combined with a tilting drive device, and one end inside the vacuum melting chamber is combined with a crucible stand, and a water-cooled copper crucible is installed on the upper end of the crucible stand.

[0028] Furthermore, a feeder connected to the vacuum melting chamber is installed on the upper side of the vacuum melting chamber, and a feeding port of the feeder is located above the water-cooled copper crucible.

[0029] Furthermore, a pressure cylinder of an extrusion device is installed above the vacuum melting chamber, and a piston rod extending downward from the pressure cylinder extends into the vacuum melting chamber through a vacuum dynamic seal and is located directly above the mold;

[0030] A pressure rod is installed at the lower end of the piston rod, and a pressure head is installed at the lower end of the pressure rod, and the shape and size of the pressure head match the inner cavity of the mold.

[0031] Compared with the prior art, the advantages of the present invention are:

[0032] 1. Aiming at the problem that there is a large difference in melting points between Al and Sc, and that the high-melting-point Sc cannot be melted in the low-temperature Al liquid after the low-melting-point Al is melted, the present invention proposes two processes of first melting the high-melting-point Sc-Al alloy and then adding Al to the alloy, which provides a technical guarantee for obtaining an Al-Sc alloy with accurate and uniform composition.

[0033] 2. The squeeze casting technology can be used to directly produce target blanks with the required shape and size in the melting chamber without the need for subsequent hot processing, which is particularly important for Al-Sc alloys with high Sc content that cannot be hot processed.

[0034] 3. Squeeze casting technology allows the semi-liquid alloy to solidify rapidly under pressure, eliminating metallurgical defects such as segregation, pores, cracks, etc. in the billet, and can form a fine-grained structure.

[0035] 4. Using suspension smelting technology to smelt Al-Sc alloy with high Sc content can eliminate the contamination of the molten pool by the crucible material during the smelting process and obtain high-purity materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0037] Figure 1 is a schematic diagram of a suspension smelting device of the present invention;

[0038] Figure 2 For the squeeze casting process Figure 1 ;

[0039] Figure 3 For the squeeze casting process Figure 2 ;

[0040] Figure 4 For the squeeze casting process Figure 3 .

[0041] In the figure, 01-water-cooled copper crucible, 02-vacuum melting chamber, 03-induction coil, 04-electrode, 05-mold, 06-feeder, 07-feeding port, 08-crucible tilting shaft, 09-crucible stand, 10-pressure cylinder, 11-piston rod, 12-pressure rod, 13-pressure head, 14-molten pool, 15-mold seat, 16-pressure cylinder seat, 17-vacuum dynamic seal, 18-vacuum pipeline. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0043] It should be noted that, in addition to the requirements for geometric size and shape, high-end target materials also have the following requirements for materials: low impurity content, precise and uniform composition, no metallurgical defects such as component segregation, pores and cracks, fine grains, etc. The purpose of this embodiment is to propose a preparation method for preparing Al-Sc alloy planar target materials with high Sc content, that is, to propose a preparation method for this material that can achieve the above requirements for high-end target materials.

[0044] The Al-Sc alloy phase diagram (X0, X1, X2, and X3 indicated in the figure are exemplary marks) can be found in "China Nonferrous Metals Industry Association, Tang Renzheng, Tian Rongzhang, Binary Alloy Phase Diagram and Interphase Crystal Structure, Central South University Press, 2009.4, P76".

[0045] It is understandable that medium frequency vacuum induction melting is the most common technology for melting alloy materials. However, when using this technology to melt Al-Sc alloy, Sc, as a rare earth element in the alloy, will react strongly with the crucible material, resulting in a significant increase in impurity content; for Al-Sc alloys with high Sc content, this problem is even more serious.

[0046] like Figure 1-4 As shown, for this purpose, this embodiment proposes to use suspension melting technology to melt Al-Sc alloy with high Sc content. X0 (X0 = 0.1 ~ 0.7) method. The water-cooled copper crucible 01 used in vacuum levitation melting technology is divided into several petals along the crucible axis direction. The electromagnetic field generates a levitation force on the material in the water-cooled copper crucible 01, so that the molten pool is separated from the inner wall of the water-cooled copper crucible 01 and is in a suspended state, eliminating the contamination of the crucible material to the molten pool. Therefore, the use of levitation melting technology to melt Al-Sc alloys with high Sc content can meet the strict requirements of high-end target materials on impurity content.

[0047] Specifically, the water-cooled copper crucible 01 is installed in the vacuum melting chamber 02, and the induction coil 03 installed on the outer periphery of the water-cooled copper crucible 01 is connected to the induction power supply outside the vacuum melting chamber 02 through the electrode 04. A mold 05 is installed at the lower position on one side of the water-cooled copper crucible 01, and the shape and diameter of its inner cavity match the design requirements of the target blank.

[0048] A feeder 06 connected to the vacuum melting chamber 02 is installed on the top of the vacuum melting chamber 02, and the feed port 07 of the feeder is located above the water-cooled copper crucible 01; the crucible tilting shaft 08 penetrates the side wall of the vacuum melting chamber 02 through a vacuum dynamic seal, and one end of the crucible outside the vacuum melting chamber 02 is combined with the tilting drive device, and the other end inside the vacuum melting chamber 02 is combined with the crucible stand 09, and the water-cooled copper crucible 01 is installed on the upper end of the crucible stand 09. Therefore, starting the tilting drive device can drive the water-cooled copper crucible 01 and the induction coil 03 to flip through the crucible tilting shaft 08.

[0049] A pressure cylinder 10 of an extrusion device is also installed on the top of the vacuum melting chamber 02. The piston rod 11 extending downward from the pressure cylinder 10 extends into the vacuum melting chamber 02 through the vacuum dynamic seal 17 and is located directly above the mold 05. A pressure rod 12 is installed at the lower end of the piston rod 11. A pressure head 13 is installed at the lower end of the pressure rod 12, and the shape and size of the pressure head 13 match the inner cavity of the mold 05. It can be understood that the extrusion device can adopt a pneumatic system, a hydraulic system or a motor pressure system. In these three systems, the pressure cylinder is respectively called a gas cylinder, an oil cylinder and an electric cylinder, and the pressure cylinder 10 is installed on the pressure cylinder seat. Since the mold 05 is subjected to a large pressure, it cannot be directly installed on the bottom surface of the vacuum melting chamber 02. Therefore, a mold seat 15 is set, and its bracket extends downward to the bottom of the vacuum melting chamber 02 through the vacuum dynamic seal 17, and the pressure of the mold 05 is borne by the ground.

[0050] This embodiment also proposes a method for making the accuracy and uniformity of alloy components meet the requirements during the suspension smelting process. It should be noted that if the Al and Sc raw materials are mixed according to the proportion of alloy components and all are placed in the water-cooled copper crucible 01 for smelting according to the general smelting process, Al with a melting point of 660°C will first melt to form a molten pool 14, and Sc with a melting point of 1541°C will be almost unable to melt in the low-temperature liquid pool; suspension smelting has a disadvantage that once the material is melted, it is difficult to continue to increase the temperature; and the Al-Sc alloy with a high Sc content used for the target material has a considerable proportion of Al, so the low-temperature molten pool 14 formed by the melting of Al occupies a large volume ratio, preventing the smelting temperature from continuing to increase.

[0051] In view of the above problems, this embodiment proposes two methods for preparing Al-Sc alloy planar targets with high Sc content:

[0052] The first process method is to use a target composition of AlSc X0 Alloy AlSc X0 (X0 = 0.1 ~ 0.7at.), according to the total Sc amount required for this alloy and according to the composition AlSc X1 (X1>X0) Add the raw materials Sc and Al into the water-cooled copper crucible 01, and add AlSc X0 Alloy with AlSc X1 The raw material Al is added to the feeder 06 according to the difference of Al required by the alloy; when the Sc and Al in the water-cooled copper crucible 01 are completely melted and alloyed, Al is slowly added from the feeder 06 to the water-cooled copper crucible 01 until the materials in the water-cooled copper crucible 01 are completely melted, alloyed and completely uniform, forming AlSc X0 alloy.

[0053] In this process, X1 is generally selected near the composition of AlSc2 (0.65-0.7at.), and according to this composition, the volume ratio of Sc in the water-cooled copper crucible 01 is significantly greater than the volume ratio of Al, so even if the Al in the water-cooled copper crucible 01 melts first, due to its small volume ratio, the Sc in the water-cooled copper crucible 01, which occupies a large volume ratio, can still continue to heat up until it is completely melted to form a high-temperature molten pool 14. Thereafter, the Al added from the feeder 06 can be quickly melted into such a high-temperature molten pool.

[0054] The second process is also based on AlSc X0 Alloy AlSc X0 (X0 = 0.1 ~ 0.7at.) All the Sc required and AlSc according to the composition X1 (X1>X0) Add Al to the water-cooled copper crucible 01; After the material is melted, alloyed and solidified, turn over the water-cooled copper crucible 01 with the composition of AlSc X1 Alloy ingots, and according to the composition AlSc X2 (X1>X2>X0) and AlSc X1 The difference in the amount of Al required is added to the water-cooled copper crucible 01; after the material is melted, alloyed and solidified, the composition of the water-cooled copper crucible 01 is turned over and AlSc X2 The alloy ingot is then divided into two parts according to the composition of AlSc X3 (X2>X3>X0) and AlSc X2 Add Al to the water-cooled copper crucible 01 according to the difference in the amount of Al required, and so on, until a composition of AlSc is obtained. X0 Alloy. Above AlSc X1 X1 can be selected near the composition of AlSc2 (0.65-0.7at.) as in the first process, and X2, X3, and X4 can be selected near the composition of AlSc, Al2Sc, and Al3Sc. Thus, each smelting process is to melt a small amount of Al together with the Al-Sc alloy ingot with a higher melting point, so a satisfactory smelting effect can be obtained.

[0055] It is worth noting that the process of melting Al-Sc alloy using the first process is relatively simple, but it has high requirements for the equipment and the process must be strictly controlled: first, the equipment must be equipped with a feeder 06 connected to the vacuum melting chamber 02, and the structure of the feeder 06 must ensure that the feeding process is smooth and controllable; second, the process of adding Al from the feeder 06 must be slow and uniform, and the power must be increased after each addition of Al for a period of time to ensure that the added Al is completely melted, so that the temperature of the molten pool 14 rises. Adding Al too quickly will cause the molten pool 14 to cool rapidly, resulting in the precipitation of high-melting-point Al-Sc intermetallic compounds from the molten pool 14, and the temperature of the molten pool 14 will no longer rise, and the smelting process cannot be completed; third, there is a temperature difference between the upper and lower parts of the water-cooled copper crucible 01. The smelting process requires increased power and strong electromagnetic stirring, otherwise it will cause uneven composition, and even precipitation of high-melting-point phases will occur in the lower part of the water-cooled copper crucible 01. The process of the second process is more cumbersome and complicated, but the effect is more reliable.

[0056] This embodiment adopts the extrusion casting technology to obtain the target material blank that meets the shape, size and material requirements.

[0057] Specifically, after the smelting process is completed, the alloy liquid in the water-cooled copper crucible 01 is poured into the mold 05. After the residence time t1, the extrusion device is started, and the piston rod 11 drives the pressure rod 12 to move downward, and the pressure head 13 is pressed into the mold to apply pressure P to the semi-solidified material. The pressure state is maintained for a period of time t2. When the casting billet is completely solidified, the piston rod 11 is lifted, and the pressure head 13 is withdrawn from the mold 05. When the billet is cooled, the vacuum melting chamber 02 is opened to take out the billet. t1 = 0.1 ~ 5min, t2 = 0.2 ~ 50min, P = 1 ~ 100MPa, and the actual value depends on the alloy composition, the weight of the billet and the cross-sectional area of ​​the mold.

[0058] The use of extrusion casting technology to prepare target blanks has the following advantages: First, after the smelting process is completed, a target blank that meets the shape and size requirements can be directly produced in the smelting equipment without the need for subsequent hot processing, which is particularly important for Al-Sc alloys with high Sc content that cannot be hot processed; Second, during the extrusion casting process, the semi-liquid metal in mold 05 solidifies rapidly, and no obvious component segregation can be formed in a very short time; Third, the semi-liquid metal in mold 05 solidifies under the action of three-dimensional compressive stress, eliminating pores and cracks in the material; Fourth, since the crystal nucleus has no time to grow during the rapid solidification process, and the pressure has a crushing effect on the crystal nucleus, the extrusion cast blank has a fine-grained structure.

[0059] It should be noted that the Al-Sc alloy target blank with a diameter that meets the requirements can be divided into several target materials with thicknesses that meet the requirements by wire cutting; for the target blank with a smaller diameter, the diameter can be increased by vacuum hot pressing or hot isostatic pressing, and the grains can be further refined before being subjected to wire cutting processing.

[0060] The present invention provides some specific embodiments to better understand the present implementation mode:

[0061] Example 1

[0062] In this embodiment, AlSc is smelted using a suspension smelting device. 0.2 Alloy, the planned smelting amount is 15kg. The water-cooled copper crucible for suspension smelting is installed in a vacuum smelting chamber, with an inner diameter of 180mm, a depth of 360mm, and is divided into 28 petals along the axial direction. A carbon steel mold with a cylindrical inner cavity is installed at the lower front of the crucible, and the inner diameter of the mold is 310mm and the depth is 500mm. A feeder connected to the smelting chamber is installed above the smelting chamber, and the feeding port of the feeder is located above the crucible. In this embodiment, the extrusion device of the suspension smelting equipment is a hydraulic press with a maximum pressure of 100 tons. Its oil cylinder is installed above the smelting chamber, and the piston rod extending downward from the pressure cylinder extends into the smelting chamber through a vacuum dynamic seal and is located directly above the mold. A pressure rod is installed at the lower end of the piston rod, and a pressure head is installed at the lower end of the pressure rod. The pressure head is cylindrical and has a diameter of 309mm.

[0063] In AlSc 0.2 The mass fraction of Sc in the alloy is 29.5%. 0.2 4425g of raw material Sc required for the alloy was added to the crucible, and the alloy AlSc with a composition close to AlSc2 was 0.6 (The mass percentage of Al is 29%) The required amount of Al, 1807 g, is also added to the crucible. 15 kg of AlSc 0.2 The amount of Al required for the alloy is 10575 g. After deducting the Al already added to the crucible, the remaining 8768 g of raw material Al is added to the feeder.

[0064] After the melting chamber is evacuated and filled with argon through the vacuum pipe 18, the material in the crucible is heated by an induction power supply. When the Sc and Al in the crucible are completely melted and alloyed, Al is slowly added to the crucible from the feeder until the material in the crucible is completely melted, alloyed and completely uniform, forming an AlSc with uniform composition. 0.2 alloy.

[0065] After the smelting process is completed, the crucible tilting device is started to pour the alloy liquid in the crucible into the mold. After staying for 0.2 minutes, the extrusion device is started, and the piston rod drives the pressure rod to move downward quickly, so that the pressure head is pressed into the mold, and a pressure of 10MPa is applied to the semi-solidified material. After maintaining the pressure for 30 minutes, the piston rod is lifted to make the pressure head withdraw from the mold. Wait for another hour, open the smelting chamber after the mold temperature drops, and take out the round cake-shaped billet.

[0066] Example 2

[0067] This embodiment also uses suspension smelting equipment to smelt AlSc 0.2 Alloy, all crucibles and equipment are the same as in Example 1.

[0068] In this embodiment, 15 kg of AlSc 0.2 The alloy is obtained through three smelting processes.

[0069] The first smelting is to add 4425g of raw material Sc and 1807g of raw material Al into the crucible. After the melting chamber is evacuated and filled with argon, the induction power supply is started to heat the materials in the crucible. After the materials are completely melted, they are kept warm for 5 minutes to form AlSc with uniform composition. 0.6 After stopping heating, the melting chamber is opened when the alloy ingot in the crucible cools down, the alloy ingot in the crucible is turned over, and 3387g of raw material Al is added. The vacuum is re-evacuated, argon is filled, and the induction voltage is started to heat the material in the crucible to melt and form AlSc 0.33 Alloy (Al2Sc). After the alloy ingot is cooled, the melting chamber is opened again, the alloy ingot is turned over and 5381g of raw material Al is added. Finally, vacuum is evacuated again, argon is filled and the induction power supply is started to heat the material in the crucible to melt and form AlSc 0.2 After the crucible is tilted to inject the alloy liquid into the mold, the extrusion device is started to pressurize the semi-liquid metal in the mold, so that the material solidifies under pressure to form a billet. The process of extrusion casting is the same as that of Example 1.

[0070] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for preparing a planar target of an Al-Sc alloy with a high Sc content, characterized in that: The steps include: S1, for the target composition of AlSc X0 Alloy AlSc X0 , according to AlSc X0 The total amount of Sc required for the alloy and the composition of AlSc X1 Add the raw materials Sc and Al into a water-cooled copper crucible; Among them, X0=0.1~0.7at., X1>X0; S2. After Sc and Al in the water-cooled copper crucible are melted, Al is added to the water-cooled copper crucible to melt the target composition of AlSc. X0 Alloy AlSc X0 ; S3. After the smelting process is completed, the alloy liquid in the water-cooled copper crucible is poured into the mold. When the molten liquid is in a semi-solidified state, the extrusion device is started to extrude the semi-solidified material to form an Al-Sc alloy flat target.

2. The preparation method according to claim 1, characterized in that: Step S2 includes the following steps: S21, according to AlSc X0 Alloy with AlSc X1 The difference of Al required by the alloy is added to the feeder to add raw material Al; S22. During the smelting of AlScX1 alloy, after Sc and Al in the water-cooled copper crucible are completely melted and alloyed, Al is added to the water-cooled copper crucible from the feeder in 2 to 5 times. After each addition of Al, wait until the added Al is completely melted and homogenized before adding Al again, until all the materials in the water-cooled copper crucible are melted, alloyed and completely homogenized to form AlScX1. X0 alloy.

3. The preparation method according to claim 1, characterized in that: Step S2 includes the following steps: S21, in smelting AlSc X1 After the alloying process is completed, turn over the water-cooled copper crucible containing AlSc X1 Alloy ingots, and according to the composition AlSc X2 With AlSc X1 The difference in the amount of Al required is added to the water-cooled copper crucible; S22, in smelting AlSc X2 After the alloying process is completed, the composition of the water-cooled copper crucible is turned over to be AlSc X2 The alloy ingot is then divided into two parts according to the composition of AlSc X3 With AlSc X2 Add Al to the water-cooled copper crucible according to the difference in the amount of Al required; S23, and so on, until the composition is AlSc X0 Alloys; Among them, X1>X2>X3>X0.

4. The preparation method according to claim 2, characterized in that: X1 is selected as 0.65~0.7at.

5. The preparation method according to claim 3, characterized in that: X1 is selected from 0.65 to 0.7 at., and X2, X3, and X4 are selected near the composition of AlSc, Al2Sc, and Al3Sc.

6. The preparation method according to claim 2, characterized in that: After adding Al, the power needs to be increased for a period of time to ensure that the added Al is completely melted and the temperature of the molten pool rises; And / or, the melting process requires increased power and stronger electromagnetic stirring.

7. The preparation method according to claim 1, characterized in that: In step S3, after the smelting process is completed, the alloy liquid in the water-cooled copper crucible is poured into the mold. After a residence time of 0.1 to 5 minutes, the extrusion device is started, and the piston rod drives the pressure rod to move downward, so that the pressure head is pressed into the mold to apply pressure P to the semi-solidified material, where P = 1 to 100 MPa; The pressure state is maintained for a period of 0.2 to 50 minutes. When the casting blank is completely solidified, the piston rod is lifted to allow the pressure head to withdraw from the mold. When the blank is cooled, the vacuum melting chamber is opened to take out the blank.

8. A preparation device for a planar target of an Al-Sc alloy with a high Sc content, applied to the preparation method according to any one of claims 1 to 7, characterized in that: It includes a water-cooled copper crucible installed in a vacuum melting chamber, and an induction coil installed on the periphery of the water-cooled copper crucible is connected to an induction power supply outside the vacuum melting chamber through an electrode; A mold is installed at the lower side of the water-cooled copper crucible, and the shape and diameter of the inner cavity thereof match the design requirements of the target blank; The crucible tilting shaft penetrates the side wall of the vacuum melting chamber through a vacuum dynamic seal, and one end outside the vacuum melting chamber is combined with a tilting drive device, and one end inside the vacuum melting chamber is combined with a crucible stand, and a water-cooled copper crucible is installed on the upper end of the crucible stand.

9. The preparation device according to claim 8, characterized in that: A feeder connected with the vacuum melting chamber is installed on the upper side of the vacuum melting chamber, and a feeding port of the feeder is located above the water-cooled copper crucible.

10. The preparation device according to claim 8, characterized in that: A pressure cylinder of an extrusion device is also installed above the vacuum melting chamber. A piston rod extending downward from the pressure cylinder extends into the vacuum melting chamber through a vacuum dynamic seal and is located just above the mold. A pressure rod is installed at the lower end of the piston rod, and a pressure head is installed at the lower end of the pressure rod, and the shape and size of the pressure head match the inner cavity of the mold.

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