A device for preparing a multilayer nanocomposite rod by a backward extrusion process

Abstract

The application is a device for preparing multilayer nanocomposite rods by a reverse extrusion process. The device utilizes good flowability of powder materials, and through deformation temperature and deformation direction changing in stages, the powder ingot is densified, deformed and surface modified at certain temperature and pressure. In this process, the pores between the powder particles completely disappear, achieving full densification. At the same time, the outer layer metal and the inner layer metal form an integral whole through over-organization, realizing solidification-organization-forming integration of the powder component. Compared with the powder rolling method and the spray deposition method, the process flow is greatly shortened, and the cost is reduced, so that a dense and fine recrystallized structure is prepared.

Description

Technical Field

[0001] This invention relates to an apparatus for preparing multilayer nanocomposite rod blanks using a reverse extrusion process, belonging to the field of thermal processing technology. Background Technology

[0002] There are many processing methods for single-layer or multi-layer modification of metal surfaces. For powder metallurgy materials, the methods generally include powder rolling and spray deposition. Powder rolling has two variations: one involves loosely spreading powder onto a base metal strip, then rolling and sintering to form a bimetallic composite material; the other uses two funnels to simultaneously feed powder, rolling it into a bimetallic powder strip, followed by further sintering and rolling to obtain the bimetallic composite material. This method is characterized by its long cycle time and is generally used for preparing plate-shaped components. Spray deposition involves using molten liquid metal, under pressure or its own weight, to flow out from a guide tube at the bottom of a crucible, forming a stable liquid metal stream. As the liquid metal stream passes through an atomizer, it is dispersed into extremely fine jets of liquid metal particles by a high-pressure, high-speed inert gas. Some of the smaller particles in the jet condense and solidify, while some larger particles remain in the liquid phase, in a solid or semi-solid state. This jet impacts, condenses, and solidifies the base material below, with most of it forming a deposition layer. This deposition layer adheres to the base material, thus forming the composite material. The limitation of this method is that the sediment forms an excessively thick liquid phase layer at the top, which will degenerate into a soil-like casting structure, making it difficult to prepare thick-walled components. In addition, due to the uneven distribution of material in the metal jet, the dimensional accuracy of the sediment layer is low. Summary of the Invention

[0003] This invention addresses the shortcomings of existing domestic technologies by providing a device for preparing multilayer nanocomposite rod blanks using a reverse extrusion process. The purpose is to improve the production efficiency of titanium-aluminum multilayer nanocomposite rod blanks and enhance their microstructure.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] The apparatus for preparing multilayer nanocomposite rod blanks by reverse extrusion process described in the technical solution of this invention is designed for extruding powder ingot 4 into rod blanks, and the apparatus includes:

[0006] The power unit 2, located on the outermost part of the device, is ring-shaped and divided into four parts in the circumferential direction to provide radial force, and can move outward or inward.

[0007] The heating device 3, which is installed inside the power unit 2 with heat insulation protection measures, is a continuous heat source capable of providing a maximum temperature of 1400℃.

[0008] The modified material ring 5 is located inside the heating device 3. It is annular and is made of stacked single or multiple layers of metal powder to provide modification, so as to achieve the need for single-layer homogeneous modification or multi-layer heterogeneous modification of metal surface. The modified material ring 5 and the powder ingot 4 are both covered with foil strips.

[0009] The upper pressure head 1 and the lower pressure head 6 are located at the upper and lower ends of the device, respectively, forming a vertically opposing extrusion of the powder ingot 4 inside the device.

[0010] During implementation, the upper inner wall of the modified material ring 5 is machined with a 1-5° bevel angle to form a trumpet-shaped opening that is larger at the top and smaller at the bottom.

[0011] In practice, the modified material ring 5 is separated into different metal powder layers by foil strips.

[0012] In practice, the lower pressure head (6) is cylindrical and the upper pressure head (1) is inverted trapezoidal.

[0013] In practice, the powder ingot 4 is made of Ti2AlNb powder with a purity of 99.99% and a particle size of -350 mesh to -450 mesh. The surface of the powder ingot 4 is a foil strip made of a mixture of carbon nanotubes and Ti2AlNb.

[0014] Furthermore, the modified material ring 5 is made of Ti powder and Al powder with a purity of 99.99%. The Ti powder and Al powder are mechanically and uniformly mixed according to the atomic mass ratio of Ti to Al of 1:1. The surface of the modified material ring 5 is a foil strip made of a mixture of carbon nanotubes and Ti2AlNb.

[0015] In practice, the powder ingot 4 is made of FGH96 high-temperature alloy powder with a particle size of -350 mesh to -450 mesh, and the surface of the powder ingot 4 is a foil strip made of a mixture of carbon nanotubes and FGH96 high-temperature alloy powder.

[0016] Furthermore, the modified material ring 5 is made of Ti powder and Al powder with a purity of 99.99%. The inner layer of the modified material ring 5 is Ti powder and the outer layer is Al powder. The modified material ring 5 is a foil strip made of a mixture of carbon nanotubes and FGH96 high-temperature alloy powder. The Ti powder and Al powder in the modified material ring 5 are separated by a Ti+Al+carbon nanotube mixture foil strip.

[0017] Furthermore, regarding the modified material ring 5, which is made by mechanically and uniformly mixing Ti powder and Al powder, the process for preparing the composite rod blank using this device includes:

[0018] The extrusion process is as follows: The power unit 2 is activated and moved towards the center. The extrusion chamber, consisting of the power unit 2, upper pressure head 1, and lower pressure head 6, is maintained at a pressure of 500-800 MPa. The heating unit 3 is activated, and the temperature is raised to 300-500℃ and held for 1-2 hours. During this time, the foil strip on the outer surface of the powder ingot 4 has melted, and the modified material ring 5 and the Ti powder and Al powder in the powder ingot 4 come into contact, collide, and are extruded, reacting to generate a partial TiAl phase. Then, the pressure of the power unit 2 is increased to 1500-2000 MPa, and the upper pressure head 1 and lower pressure head 6 begin to move in opposite directions at a speed of 0.001-1 s. -1 At this point, the powder ingot 4 is stretched along the axis. When the length of the powder ingot 4 is consistent with the height of the modified material ring 5, the extrusion is completed.

[0019] Reverse extrusion is performed after the initial extrusion process. This reverse extrusion process involves maintaining the pressure and position of the power unit 2, upper pressure head 1, and lower pressure head 6, increasing the heating temperature of the heating device 3 to 1000-1200℃, and holding this temperature for 0.5-1 hour. During this time, the Ti powder and Al powder in the modified material ring 5 react completely to form the TiAl phase. The temperature is then lowered to 600-900℃ and held for 0.5-1 hour. Finally, the upper pressure head 1 and lower pressure head 6 move centripetally at a speed of 0.001-1 second. -1 The power unit 2 maintains a compressive stress of 1500-2000MPa and moves outward naturally. When the axial height of the powder ingot 4 returns to the initial height, the reverse extrusion is completed.

[0020] Furthermore, regarding the modified material ring 5, which is made of inner Ti powder and outer Al powder, the process for preparing the composite rod blank using this device includes:

[0021] The extrusion process is as follows: The power unit 2 is activated and moved towards the center. The extrusion chamber is formed by the power unit 2, the upper pressure head 1, and the lower pressure head 6. The pressure is maintained at 500-800 MPa. The heating unit 3 is activated, and the heating temperature is increased to... 800-900℃ The mixture is kept at a constant temperature for 1-2 hours. During this time, the foil strip on the outer surface of the powder ingot 4 has melted, and the modified material ring 5 and the Ti powder and Al powder in the powder ingot 4 come into contact, collide, and are squeezed, reacting to generate a partial TiAl phase. Then, the pressure of the power device 2 is increased to 1500-2000 MPa, and the upper pressure head 1 and the lower pressure head 6 begin to move in opposite directions at a speed of 0.001-1 s. -1 At this point, the powder ingot 4 is stretched along the axis. When the length of the powder ingot 4 is consistent with the height of the modified material ring 5, the extrusion is completed.

[0022] Reverse extrusion is performed after the initial extrusion process. This reverse extrusion process involves maintaining the pressure and position of the power unit 2, upper pressure head 1, and lower pressure head 6, increasing the heating temperature of the heating device 3 to 1000-1200℃, and holding this temperature for 0.5-1 hour. During this time, the Ti powder and Al powder in the modified material ring 5 react completely to form the TiAl phase. The temperature is then lowered to 600-900℃ and held for 0.5-1 hour. Finally, the upper pressure head 1 and lower pressure head 6 move centripetally at a speed of 0.001-1 second. -1 The power unit 2 maintains a compressive stress of 1500-2000MPa and moves outward naturally. When the axial height of the powder ingot 4 returns to the initial height, the reverse extrusion is completed.

[0023] The features and beneficial effects of the technical solution of this invention are as follows:

[0024] I. The technical solution of this invention mainly targets the surface modification of powder metallurgy bulk materials, including single-layer homogeneous surface modification and multi-layer heterogeneous surface modification. Through the implementation of the technical solution of this invention, powder metallurgy bulk materials such as titanium alloys, high-temperature alloys and structural steel can be surface modified according to actual applications.

[0025] II. The surface modification equipment involved in the technical solution of this invention consists of a power device, a heating device, a modified material ring, and a powder ingot from the outside to the inside during the working process. For single-layer homogeneous modification, the process from powder ingot forming to surface modification only requires one extrusion and one reverse extrusion. For multi-layer heterogeneous modification, the process also only requires one extrusion and one reverse extrusion through the layered design of the modified material ring.

[0026] 3. The original state of the powder metallurgy bulk material undergoing surface modification is powder particles. The powder particles are packed in a special tooling to form a powder ingot. During the extrusion process, the powder ingot achieves self-solidification and solidification of the surface-modified powder layer and its interface fusion. During the reverse extrusion process, the powder ingot achieves plastic deformation and plastic deformation of the surface-modified powder layer and its interface reaction. The resulting surface-modified powder metallurgy bulk material has a fine structure, superior performance, and the modified layer is tightly integrated with the matrix. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the device structure in the technical solution of the present invention.

[0028] Figure 2 This is a schematic diagram of the multilayer nanocomposite rod structure in the technical solution of this invention. Detailed Implementation

[0029] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments:

[0030] Example 1:

[0031] The steps for preparing single-layer homogeneous or multi-layer heterogeneous powder-modified nanocomposite rod preforms using the apparatus of the present invention are as follows:

[0032] Step 1: Preparation of the apparatus

[0033] See appendix Figure 1 As shown, the device of the present invention includes:

[0034] This apparatus is designed for extruding powder ingots 4 into bar blanks. The apparatus includes:

[0035] The power unit 2, located on the outermost part of the device, is ring-shaped and divided into four parts in the circumferential direction to provide radial force, and can move outward or inward.

[0036] The heating device 3, which is installed inside the power unit 2 with heat insulation protection measures, is a continuous heat source capable of providing a maximum temperature of 1400℃.

[0037] The modified material ring 5, located inside the heating device 3, is annular and is formed by pressing a single or multiple layer of modified metal powder to achieve the need for single-layer homogeneous modification or multi-layer heterogeneous modification of the metal surface; the upper inner wall of the modified material ring 5 is machined with a 1-5° bevel angle to form a funnel-shaped opening that is larger at the top and smaller at the bottom;

[0038] The upper pressure head 1 and the lower pressure head 6 are cylindrical and inverted trapezoidal, respectively located at the upper and lower ends of the device, forming a vertical extrusion of the powder ingot 4 in the device.

[0039] Step 2: Preparation of single-layer homogeneous modified material ring 5

[0040] In this embodiment, the powder ingot 4 is made of Ti2AlNb powder with a purity of 99.99% and a particle size of -350 mesh to -450 mesh. The surface of the powder ingot 4 is a foil strip made of a mixture of carbon nanotubes and Ti2AlNb.

[0041] The modified ring 5, which is compatible with the powder ingot 4, is a single-layer homogeneous modified ring made of Ti powder and Al powder with a purity of 99.99%. The Ti powder and Al powder are mechanically and uniformly mixed according to the atomic mass ratio of Ti to Al of 1:1. The surface of the modified ring 5 is a foil strip made of a mixture of carbon nanotubes and Ti2AlNb.

[0042] Step 3, extrusion. The extrusion process is as follows: Start the power unit 2 and move it towards the center. The extrusion chamber is formed by the power unit 2, the upper pressure head 1, and the lower pressure head 6. The pressure is maintained at 500-800 MPa. Start the heating unit 3 and heat the temperature to 300-500℃. Hold the temperature for 1-2 hours. At this time, the foil strip on the outer surface of the powder ingot 4 has melted, and the modified material ring 5 and the Ti powder and Al powder in the powder ingot 4 come into contact, collide, and are extruded, reacting to generate a partial TiAl phase. Then, increase the pressure of the power unit 2 to 1500-2000 MPa, and the upper pressure head 1 and the lower pressure head 6 begin to move in opposite directions at a speed of 0.001-1 s. -1 At this point, the powder ingot 4 is stretched along the axis. When the length of the powder ingot 4 is consistent with the height of the modified material ring 5, the extrusion is completed.

[0043] During this process, the powder in the modified ring 5 and the powder ingot 4 was completely crushed and solidified. At the contact point between the modified ring 5 and the powder ingot 4, a chemical reaction occurred. The Ti powder, Al powder and TiAl phase in the modified ring 5 combined with the Ti2AlNb powder in the powder ingot (4) to generate the TiAlxNby phase, TixNby phase and AlxNby phase.

[0044] Step 4: Reverse extrusion. After the initial extrusion process, reverse extrusion is performed. This reverse extrusion process is as follows: Maintain the pressure and position of the power unit 2, upper pressure head 1, and lower pressure head 6; increase the heating temperature of the heating device 3 to 1000-1200℃ and hold for 0.5-1 hour. During this time, the Ti powder and Al powder in the modified material ring 5 react completely to form the TiAl phase. Then, the temperature is lowered to 600-900℃ and held for 0.5-1 hour. Next, the upper pressure head 1 and lower pressure head 6 move centripetally at a speed of 0.001-1 second. -1 The power unit 2 maintains a compressive stress of 1500-2000MPa and moves outward naturally. When the axial height of the powder ingot 4 returns to the initial height, the reverse extrusion is completed.

[0045] At this time, the powder ingot 4 is compressed along the axis, and the structure at the interface between the powder ingot 4 and the modified material ring (5) begins to undergo plastic deformation. Under the action of axial and radial compressive stress, the structure undergoes plastic deformation and begins to refine.

[0046] Step 5: Post-processing

[0047] Take out the reverse extrusion powder ingot 4, cool it, and observe the cross-sectional changes of powder ingot 4. This completes the reverse extrusion process for preparing single-layer homogeneous modified powder metallurgy bulk material.

[0048] After the powder ingot 4 is processed and cooled as described above, the preparation of a single-layer homogeneous powder modified metallurgical bulk material by reverse extrusion process is completed. The surface heat resistance of the Ti2AlNb bulk material modified by the single-layer homogeneous TiAl surface can be improved.

[0049] Example 2:

[0050] The steps for preparing single-layer homogeneous or multi-layer heterogeneous powder-modified nanocomposite rod preforms using the apparatus of the present invention are as follows:

[0051] Step 1: Preparation of the apparatus

[0052] See appendix Figure 1 As shown, the device in this embodiment is the same as that in Embodiment 1;

[0053] Step 2: Preparation of the bilayer heterogeneous modified material ring 5

[0054] In this embodiment, the powder ingot 4 is made of FGH96 high-temperature alloy powder with a particle size of -350 mesh to -450 mesh. The surface of the powder ingot 4 is a foil strip made of a mixture of carbon nanotubes and FGH96 high-temperature alloy powder.

[0055] The modified material ring 5 adapted to the powder ingot 4 is a double-layer heterogeneous modified material ring, made of Ti powder and Al powder with a purity of 99.99%. The inner layer of the modified material ring 5 is Ti powder and the outer layer is Al powder. The modified material ring 5 is a foil strip made of a mixture of carbon nanotubes and FGH96 high-temperature alloy powder. The Ti powder and Al powder in the modified material ring 5 are separated by a Ti+Al+carbon nanotube mixture foil strip.

[0056] Step 3, extrusion. The extrusion process is as follows: Start the power unit 2 and move it towards the center. The extrusion chamber is formed by the power unit 2, the upper pressure head 1, and the lower pressure head 6. The pressure is maintained at 500-800 MPa. Start the heating unit 3 and heat the temperature to 800-900℃, holding it at that temperature for 1-2 hours. At this time, the foil strip on the outer surface of the powder ingot 4 has melted, and the modified material ring 5 and the Ti powder and Al powder in the powder ingot 4 come into contact, collide, and are extruded, reacting to generate a partial TiAl phase. Then, increase the pressure of the power unit 2 to 1500-2000 MPa, and the upper pressure head 1 and the lower pressure head 6 begin to move in opposite directions at a speed of 0.001-1 s. -1 At this point, the powder ingot 4 is stretched along the axis. When the length of the powder ingot 4 is consistent with the height of the modified material ring 5, the extrusion is completed.

[0057] During this process, FGH96 high-temperature alloy powder generated TiAlx-FGH96 phase, Tix-FGH96 phase and Alx-FGH96 phase;

[0058] Step 4: Reverse extrusion. After the initial extrusion process, reverse extrusion is performed. This reverse extrusion process is as follows: Maintain the pressure and position of the power unit 2, upper pressure head 1, and lower pressure head 6; increase the heating temperature of the heating device 3 to 1000-1200℃ and hold for 0.5-1 hour. During this time, the Ti powder and Al powder in the modified material ring 5 react completely to form the TiAl phase. Then, the temperature is lowered to 600-900℃ and held for 0.5-1 hour. Next, the upper pressure head 1 and lower pressure head 6 move centripetally at a speed of 0.001-1 second. -1 The power unit 2 maintains a compressive stress of 1500-2000MPa and moves outward naturally. When the axial height of the powder ingot 4 returns to the initial height, the reverse extrusion is completed.

[0059] At this time, the powder ingot 4 is compressed along the axis, and the structure at the interface between the powder ingot 4 and the modified material ring (5) begins to undergo plastic deformation. Under the action of axial and radial compressive stress, the structure undergoes plastic deformation and begins to refine.

[0060] In this process, the surface wear resistance of FGH96 alloy material can be improved by heterogeneous modification with double-layer Ti and Al powder.

[0061] Step 5: Post-processing

[0062] Take out the reverse extrusion powder ingot 4, cool it, and observe the cross-sectional changes of powder ingot 4. This completes the reverse extrusion process for preparing single-layer homogeneous modified powder metallurgy bulk material.

[0063] After the powder ingot 4 is processed and cooled as described above, the preparation of the double-layer heterogeneous powder modified metallurgical bulk material by reverse extrusion process is completed. The surface heat resistance of the Ti2AlNb bulk material modified by the single-layer homogeneous TiAl surface can be improved.

Claims

1. An apparatus for preparing multilayer nanocomposite rod preforms using a reverse extrusion process, characterized in that: This device is designed for extruding powder ingots (4) into rod blanks. During operation, the process from powder ingot forming to surface modification only requires one extrusion and one reverse extrusion. The device includes: The power unit (2) is located on the outermost part of the device. It is ring-shaped and divided into four parts in the circumferential direction to provide radial force and can move outward or inward. The heating device (3), which is installed inside the power unit (2) with heat insulation protection measures, is a continuous heat source that can provide a maximum temperature of 1400℃. The modified material ring (5) is located inside the heating device (3). It is annular and is made of stacked single or multiple layers of metal powder to provide modification, so as to realize the need for single-layer homogeneous modification or multi-layer heterogeneous modification of metal surface. The modified material ring (5) and the powder ingot (4) are both covered with foil strips. The upper pressure head (1) and the lower pressure head (6) are located at the upper and lower ends of the device, respectively, forming a vertical extrusion of the powder ingot (4) inside the device.

2. The apparatus for preparing multilayer nanocomposite rod blanks by reverse extrusion process according to claim 1, characterized in that: The upper inner wall of the modified material ring (5) is machined with a 1-5º bevel angle to form a trumpet-shaped opening that is larger at the top and smaller at the bottom.

3. The apparatus for preparing multilayer nanocomposite rod blanks by reverse extrusion process according to claim 1, characterized in that: The modified material ring (5) is separated into different metal powder layers by foil strips.

4. The apparatus for preparing multilayer nanocomposite rod blanks by reverse extrusion process according to claim 1, characterized in that: The lower pressure head (6) is cylindrical, and the upper pressure head (1) is inverted trapezoidal.

5. The apparatus for preparing multilayer nanocomposite rod blanks by reverse extrusion process according to any one of claims 1-4, characterized in that: The powder ingot (4) is made of Ti2AlNb powder with a purity of 99.99% and a particle size of -350 mesh to 450 mesh. The surface of the powder ingot (4) is a foil strip made of a mixture of carbon nanotubes and Ti2AlNb.

6. The apparatus for preparing multilayer nanocomposite rod blanks by reverse extrusion process according to claim 5, characterized in that: The modified material ring (5) is made of Ti powder and Al powder with a purity of 99.99%. The Ti powder and Al powder are mechanically and uniformly mixed according to the atomic mass ratio of Ti to Al of 1:

1. The surface of the modified material ring (5) is a foil strip made of a mixture of carbon nanotubes and Ti2AlNb.

7. The apparatus for preparing multilayer nanocomposite rod preforms by reverse extrusion process according to any one of claims 1-4, characterized in that: The powder ingot (4) is made of FGH96 high-temperature alloy powder with a particle size of -350 mesh to 450 mesh. The surface of the powder ingot (4) is a foil strip made of a mixture of carbon nanotubes and FGH96 high-temperature alloy powder.

8. The apparatus for preparing multilayer nanocomposite rod preforms by reverse extrusion process according to claim 7, characterized in that: The modified ring (5) is made of Ti powder and Al powder with a purity of 99.99%. The inner layer of the modified ring (5) is Ti powder and the outer layer is Al powder. The outer surface of the modified ring (5) is covered with a foil strip made of a mixture of carbon nanotubes and FGH96 high-temperature alloy powder. The Ti powder and Al powder in the modified ring (5) are separated by a foil strip made of a mixture of Ti powder, Al powder and carbon nanotubes.

9. The apparatus for preparing multilayer nanocomposite rod preforms by reverse extrusion process according to claim 6, characterized in that: The process for preparing composite rod blanks using this device includes: The extrusion process is as follows: the power device (2) is started and moved towards the center. The extrusion chamber is formed by the power device (2), the upper pressure head (1) and the lower pressure head (6). The pressure is maintained at 500-800 MPa. The heating device (3) is started and the heating temperature is raised to 300-500℃. The temperature is maintained for 1-2 hours. At this time, the foil strip on the outer surface of the powder ingot (4) has melted, and the Ti powder and Al powder in the modified material ring (5) come into contact, collide and are extruded with the powder ingot (4), and react to generate part of the TiAl phase. Then, the pressure of the power device (2) is increased to 1500-2000 MPa, and the upper pressure head (1) and the lower pressure head (6) begin to move in opposite directions at a speed of 0.001-1s. -1 At this time, the powder ingot (4) is stretched along the axis. When the length of the powder ingot (4) is consistent with the height of the modified material ring (5), the extrusion is completed. Reverse extrusion is performed after the extrusion process is completed. The reverse extrusion process is as follows: the pressure and position of the power device (2), the upper pressure head (1) and the lower pressure head (6) are maintained, the heating temperature of the heating device (3) is increased to 1000-1200℃ and kept at that temperature for 0.5h-1h. At this time, the Ti powder and Al powder in the modified material ring (5) react completely to form the TiAl phase. Then the temperature is lowered to 600-900℃ and kept at that temperature for 0.5h-1h. Then, the upper pressure head (1) and the lower pressure head (6) move towards the center at a speed of 0.001-1s. -1 The power unit (2) moves outward naturally while maintaining a pressure of 1500-2000MPa. When the axial height of the powder ingot (4) returns to the initial height, the reverse extrusion is completed.

10. The apparatus for preparing multilayer nanocomposite rod preforms by reverse extrusion process according to claim 8, characterized in that: The process for preparing composite rod blanks using this device includes: The extrusion process is as follows: the power device (2) is started and moved towards the center. The extrusion chamber is formed by the power device (2), the upper pressure head (1) and the lower pressure head (6). The pressure is maintained at 500-800 MPa. The heating device (3) is started and the heating temperature is raised to 800-900℃. The temperature is maintained for 1-2 hours. At this time, the foil strip on the outer surface of the powder ingot (4) has melted, and the Ti powder and Al powder in the modified material ring (5) come into contact, collide and are extruded with the powder ingot (4), and react to generate part of the TiAl phase. Then, the pressure of the power device (2) is increased to 1500-2000 MPa, and the upper pressure head (1) and the lower pressure head (6) begin to move in opposite directions at a speed of 0.001-1s. -1 At this time, the powder ingot (4) is stretched along the axis. When the length of the powder ingot (4) is consistent with the height of the modified material ring (5), the extrusion is completed. Reverse extrusion is performed after the extrusion process is completed. The reverse extrusion process is as follows: the pressure and position of the power device (2), the upper pressure head (1) and the lower pressure head (6) are maintained, the heating temperature of the heating device (3) is increased to 1000-1200℃ and kept at that temperature for 0.5h-1h. At this time, the Ti powder and Al powder in the modified material ring (5) react completely to form the TiAl phase. Then the temperature is lowered to 600-900℃ and kept at that temperature for 0.5h-1h. Then, the upper pressure head (1) and the lower pressure head (6) move towards the center at a speed of 0.001-1s. -1 The power unit (2) moves outward naturally while maintaining a pressure of 1500-2000MPa. When the axial height of the powder ingot (4) returns to the initial height, the reverse extrusion is completed.

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