Friction extrusion apparatus and method for metal matrix composites with online introduction of reinforcement phase

Abstract

The application discloses a kind of metal matrix composite friction extrusion devices of enhanced phase online introduction, including main shaft rotation lifting assembly, die assembly and powder feeding assembly.The main shaft bottom end of main shaft rotation lifting assembly is connected with stirring head, drives stirring head to complete quick lifting and lowering action while high-speed rotation;Die assembly includes cavity plate, cavity, cover plate and die base, cavity plate is opened with the feeding groove that is communicated with cavity in, can push metal matrix into cavity, so that it is contacted with stirring head;Powder feeding assembly includes powder storage, powder distribution wheel slot, powder blowing cylinder and powder blowing pipe, after stirring head is lifted and separated from cavity, quantitative reinforcing phase powder is blown into the cavity of die assembly by inert protective gas after the above-mentioned reinforcing phase online introduction of metal matrix composite friction extrusion device and method is used, can realize the online introduction of reinforcing phase in synchronous in friction extrusion process, and has higher preparation efficiency, it is convenient for industrial production.

Description

Technical Field

[0001] This invention relates to the field of composite material preparation technology, and in particular to a friction extrusion apparatus and method for introducing a reinforcing phase into a metal matrix composite material online. Background Technology

[0002] Metal matrix composites are composite materials made by combining metals or alloys with various reinforcing phases. They can leverage the advantages of both the matrix and the reinforcing phase to achieve a "1+1>2" effect, and have broad application prospects in aerospace, transportation, electronics and electrical engineering and other fields.

[0003] Preparation technology is the core competitiveness of the metal matrix composites industry. Currently, methods for preparing metal matrix composites include stir casting, powder metallurgy, pressure infiltration, chemical vapor deposition, additive manufacturing, and friction stir processing. Among these, friction stir processing utilizes a high-speed rotating stirring head to stir and rub the metal, generating stable frictional heat and driving the metal to thermoplastic form. During the forming process, the material remains in a solid phase and undergoes intense plastic deformation, which can greatly promote the dispersion and interfacial bonding of the reinforcing phase and the metal, two non-wetting materials. This is a promising new technology for preparing metal matrix composites. To address the limitation of friction stir processing in forming composite zones only in the localized area where the stirring head acts, thus restricting its application, a friction extrusion technology based on the principles of friction stir processing has been developed. This technology ensures that all materials interact with the stirring head, thereby preparing full-size composite materials.

[0004] However, currently, existing friction extrusion technology can only add reinforcing phase powder by pre-drilling holes or grooves in the metal substrate (applications 200910115723.5, 202210711766.5, 202310135724.6), or by adding a mixture of reinforcing phase and metal powder (application 201811637730.7). Alternatively, the reinforcing phase can be introduced by first mixing the reinforcing phase and metal powder and then cold-pressing it into a preform (application 201910327969.2). The process is cumbersome, and the friction extrusion process mainly relies on left-handed threads to drive the material to be extruded from the extrusion port, resulting in low preparation efficiency and making it difficult to meet the needs of industrial production. Summary of the Invention

[0005] The purpose of this invention is to provide a friction extrusion device and method for introducing a reinforcing phase online into metal matrix composites, thereby solving the problems of cumbersome processes and low efficiency in the preparation of metal matrix composites using existing friction extrusion technology.

[0006] To achieve the above objectives, the present invention provides a metal matrix composite friction extrusion device for online introduction of reinforcing phase, comprising a main shaft rotation and lifting assembly and a die assembly located in the moving extrusion direction of the main shaft rotation and lifting assembly, which together are used for mixing metal substrate and reinforcing phase powder and preparing composite materials by friction extrusion. It also includes a powder feeding assembly, which uses inert gas to quantitatively and segmentally blow the reinforcing phase powder into the mold assembly.

[0007] Preferably, the spindle rotation and lifting assembly includes a bracket, on which a spindle box is mounted, and the spindle box is connected to the bracket via a lifting structure; The lifting structure includes a lead screw, one end of which is connected to the output end of the first motor, and the other end of which is rotatably connected to the bracket. A nut seat is fitted on the lead screw, and the nut seat is threadedly connected to the lead screw. The nut seat is fixedly connected to the main shaft box. The lead screw has a guide rail fixed to the bracket on its side, and a movable slider is slidably mounted on the guide rail. The movable slider is fixedly connected to the spindle box.

[0008] Preferably, a main shaft is provided inside the main shaft box, one end of the main shaft is connected to the drive structure, and the other end of the main shaft is rigidly connected to the stirring head; The drive structure includes a first pulley coaxially connected to the end of the main shaft away from the stirring head, a second motor mounted on the main shaft box, the output shaft of the second motor connected to the second pulley, the second pulley being rotatably mounted on the main shaft box, and the second pulley being connected to the first pulley via a transmission belt.

[0009] Preferably, the mold assembly includes a mold base, a cavity support plate is provided on the mold base, a feed groove and a cavity are provided inside the cavity support plate, the feed groove is distributed along the circumference of the cavity and communicates with the cavity, and the feed groove is used to push the metal substrate into the cavity so that it contacts the stirring head.

[0010] Preferably, the stirring head is aligned with the cavity, the end of the stirring head is provided with a stirring pin, the outer wall of the stirring pin is machined with a left-hand thread, and the end of the stirring head away from the stirring pin is provided with a clamping handle, which is rigidly connected to the main shaft.

[0011] Preferably, the powder feeding assembly includes a powder storage bin, the top of which is configured as a feeding opening, and a powder distribution wheel groove is rotatably provided inside the powder storage bin, the powder distribution wheel groove being located below the opening. A third motor is installed on the outside of the powder storage bin, the output shaft of the third motor is connected to the powder distribution wheel groove, and a powder blowing cylinder is provided below the powder distribution wheel groove. A powder blowing pipe is connected to the powder blowing cylinder, and the powder blowing pipe is used to blow the reinforcing phase powder into the mold cavity.

[0012] Preferably, the powder separator has several uniformly distributed toothed grooves for storing a fixed amount of reinforcing phase powder.

[0013] Preferably, the powder blowing tube is an irregularly shaped tubular structure with a round front end and a flat rear end. The front end of the powder blowing tube near the powder blowing cylinder is round, and the rear end used for powder dispensing is flat.

[0014] This invention also provides a method for friction extrusion of metal matrix composites with an online reinforcing phase, comprising the following steps: Step 1: Start the first motor and the second motor. The first motor drives the stirring head to descend to the preset working position, and the second motor drives the stirring head to rotate at high speed. Step 2: Push the metal substrate into the cavity so that it comes into contact with the high-speed rotating stirring head and undergoes friction extrusion processing; Step 3: After the processing condition stabilizes, start the third motor to drive the powder distribution wheel groove to rotate, and quantitatively distribute the reinforcing phase powder in the powder storage bin into the powder blowing cylinder; Step 4: Quickly raise the stirring head to the preset powder feeding position away from the mold cavity, and at the same time introduce inert protective gas into the powder blowing tube to send the reinforcing phase powder into the mold cavity through the powder blowing tube. Step 5: Quickly lower the stirring head back to the preset working position and apply additional extrusion pressure to push the material out of the cavity. Step six involves the rapid reciprocating lifting and lowering of the stirring head, quantitative distribution of powder by the powder distribution wheel groove, and segmented powder feeding to complete the friction extrusion preparation of the entire metal matrix composite material.

[0015] The advantages and positive effects of the metal matrix composite friction extrusion device and method with online reinforcing phase introduction described in this invention are as follows: 1. The present invention provides a metal matrix composite friction extrusion device and method for online introduction of reinforcing phase, which can simultaneously achieve online introduction of reinforcing phase during friction extrusion, greatly simplifying the process and facilitating industrial production; 2. Compared with traditional friction extrusion devices and methods, the present invention can generate additional extrusion force simultaneously during the rapid descent of the stirring head back to the preset working position, which is beneficial to push the material to the cavity outlet and improve the preparation efficiency of composite materials.

[0016] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of an embodiment of a metal matrix composite friction extrusion device for online introduction of reinforcing phase according to the present invention; Figure 2 This is a three-dimensional axial sectional view of the powder feeding assembly in an embodiment of a metal matrix composite friction extrusion device for online introduction of reinforcing phase according to the present invention. Figure 3This is a three-dimensional structural diagram of the powder feeding component of an embodiment of a metal matrix composite friction extrusion device with online reinforcing phase introduction according to the present invention; Figure 4 This is a schematic diagram of the three-dimensional structure of a six-toothed groove powder separator wheel groove in an embodiment of a metal matrix composite friction extrusion device for online introduction of reinforcing phase according to the present invention; Figure 5 This is a schematic diagram of the three-dimensional structure of the twelve-toothed powder separator wheel groove in an embodiment of the metal matrix composite friction extrusion device for online introduction of the reinforcing phase according to the present invention; Figure 6 This is a three-dimensional structural diagram of the stirring head in an embodiment of a friction extrusion device for metal matrix composites with online reinforcing phase introduction according to the present invention; Figure 7 This is a schematic diagram of the powder feeding position in a friction extrusion method for metal matrix composites with online reinforcing phase introduction according to the present invention. Figure 8 This is a schematic diagram of the working position of a metal matrix composite friction extrusion method for introducing a reinforcing phase online according to the present invention; Figure 9 This is a flowchart illustrating the steps of a friction extrusion method for a metal matrix composite material in which an online reinforcing phase is introduced, according to the present invention.

[0018] Figure label: 1. Main shaft rotation and lifting assembly; 101. First motor; 102. Nut seat; 103. Guide rail; 104. Moving slider; 105. Lead screw; 106. Second motor; 107. First pulley; 108. Second pulley; 109. Conveyor belt; 110. Main shaft box; 111. Main shaft; 112. Stirring head; 113. Stirring needle; 114. Clamping handle; 115. Bracket; 2. Mold components; 201. Cavity; 202. Cover plate; 203. Support plate; 204. Mold base; 205. Feed chute; 3. Powder feeding assembly; 301. Powder distribution wheel groove; 302. Powder blowing cylinder; 303. Inert protective gas inlet; 304. Third motor; 305. Powder storage bin; 306. Powder blowing pipe. Detailed Implementation

[0019] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0020] In this application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. In case of any inconsistency, the meaning set forth in this specification or derived from the content described herein shall prevail. Furthermore, the terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit the scope of this application.

[0021] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0022] Example 1: like Figure 1 As shown, this embodiment provides a friction extrusion apparatus for metal matrix composites with online introduction of reinforcing phase, including a spindle rotation and lifting assembly 1, a die assembly 2, and a powder feeding assembly 3. The spindle rotation and lifting assembly 1 and the die assembly 2, located in the moving extrusion direction of the spindle rotation and lifting assembly 1, cooperate to mix the metal substrate and reinforcing phase powder and prepare the composite material through friction extrusion.

[0023] The spindle rotation and lifting assembly 1 includes a bracket 115, on which a spindle box 110 is mounted. The spindle box 110 is connected to the bracket 115 via a lifting structure.

[0024] The lifting structure includes a lead screw 105, one end of which is connected to the output end of the first motor 101, and the other end of which is rotatably connected to the bracket 115 via a bearing. A nut seat 102 is fitted onto the lead screw 105, and the nut seat 102 is threadedly connected to the lead screw 105 and fixedly connected to the spindle box 110. A guide rail 103, fixed to the bracket 115, is provided on the side of the lead screw 105, and a movable slider 104 is slidably mounted on the guide rail 103, and the movable slider 104 is fixedly connected to the spindle box 110.

[0025] A main shaft 111 is housed within the main shaft housing 110. One end of the main shaft 111 is connected to the drive structure, and the other end is rigidly connected to the stirring head 112. The drive structure includes a first pulley 107 coaxially connected to the end of the main shaft 111 furthest from the stirring head 112. A second motor 106 is mounted on the main shaft housing 110, and the output shaft of the second motor 106 is connected to a second pulley 108. The second pulley 108 is mounted on the main shaft housing 110 via a rotating shaft and is rotatably connected to the main shaft housing 110. The second pulley 108 is connected to the first pulley 107 via a transmission belt.

[0026] The first motor 101 drives the lead screw 105 to rotate, which in turn drives the nut seat 102, which is in tandem with the lead screw 105, to move linearly. This, in turn, drives the spindle box 110 to rise and fall (axial movement), thus achieving rapid axial feed of the spindle 111. The second motor 106 drives the second pulley 108 to rotate, which in turn drives the first pulley 107 to rotate via a transmission belt. The spindle 111, connected by the first pulley 107, the transmission belt 109, and the second pulley 108, is driven by the second motor 106 to achieve high-speed rotation.

[0027] Mold assembly 2, located in the moving extrusion direction of the main shaft rotation and lifting assembly, is used for the preparation and forming of metal substrate and reinforcing phase powder. Mold assembly 2 includes a mold base 204, a cavity support plate 203 on the mold base 204, and a cover plate 202 fixed on the cavity support plate 203. A feed groove 205 and a cavity 201 are provided within the cavity support plate 203. The feed groove 205 is distributed circumferentially along the cavity 201 and communicates with the cavity 201. The feed groove 205 is used to push the metal substrate into the cavity 201, allowing it to contact the stirring head 112.

[0028] like Figure 6 As shown, a stirring needle 113 is provided at the end of the stirring head 112, and a left-hand thread is machined on the outer wall of the stirring needle 113. A clamping handle 114 is provided at the end of the stirring head 112 away from the stirring needle 113, and the clamping handle 114 is rigidly connected to the main shaft 111.

[0029] like Figure 2 , Figure 3 As shown, the powder feeding assembly 3 uses inert gas to quantitatively blow reinforcing phase powder into the mold assembly 2. The powder feeding assembly 3 includes a powder storage bin 305, the top of which is configured as a feed opening. A powder distribution wheel groove 301 is rotatably arranged inside the powder storage bin 305, located below the opening. A third motor 304 is mounted on the outside of the powder storage bin 305, and the output shaft of the third motor 304 is connected to the powder distribution wheel groove 301. A powder blowing cylinder 302 is located below the powder distribution wheel groove 301, and a powder blowing pipe 306 is connected to the powder blowing cylinder 302. The powder blowing pipe 306 is used to blow the reinforcing phase powder into the mold cavity 201.

[0030] The stirring head 112 is aligned with the cavity 201. The main shaft 111 is driven by the second motor 106 and drives the stirring head 112 to rotate clockwise at high speed. The axial driving force provided by the first motor 101 enables rapid axial feeding. The third motor 304 controls the rotation of the powder distribution wheel groove 301 to quantitatively transport the powder in the powder storage bin 305 to the powder blowing cylinder 302. The inert protective gas blows the reinforcing phase powder in the powder blowing cylinder 302 through the inert protective gas inlet 303 (set on the powder blowing cylinder 302) to the preset powder feeding position in the cavity 201 through the powder blowing pipe 306.

[0031] like Figure 7 , Figure 8 , Figure 9 As shown, the present invention provides a method for friction extrusion of a metal matrix composite material with an online reinforcing phase, comprising the following steps: Step 1: Start the first motor 101 and the second motor 106. The first motor 101 drives the stirring head 112 to descend to the preset working position, and the second motor 106 drives the stirring head 112 to rotate at high speed. Step 2: Push the metal substrate into the cavity 201 so that it comes into contact with the high-speed rotating stirring head 112 for friction extrusion processing; Step 3: After the processing state stabilizes, start the third motor 304 to drive the powder distribution wheel groove 301 to rotate, and quantitatively distribute the reinforcing phase powder in the powder storage bin 305 into the powder blowing cylinder 302; Step 4: Quickly raise the stirring head 112 to the preset powder feeding position away from the mold cavity 201, and at the same time introduce inert protective gas into the powder blowing tube 302 to send the reinforcing phase powder into the mold cavity 201 through the powder blowing tube 306. Step 5: Quickly lower the stirring head 112 back to the preset working position and apply additional extrusion force to push the material out of the cavity 201. Step six: The friction extrusion preparation of the entire metal matrix composite material is completed by the rapid reciprocating lifting and lowering of the stirring head 112, the quantitative distribution of powder by the powder distribution wheel groove 301, and the segmented powder feeding.

[0032] The inert protective gas is one or both of high-purity argon and nitrogen. The metal substrate includes one or more of aluminum, magnesium, copper, and zinc.

[0033] The reinforcing phase includes one or more of whisker-type reinforcing phases, particulate reinforcing phases, and other types of reinforcing phases. Other types of reinforcing phases include one or more of carbon nanotubes, graphene, and diamond. The reinforcing phase can be a pure reinforcing phase powder or a mixed reinforcing phase powder mixed with metal substrate powder. In this invention, the diameter of the whisker-type reinforcing phase is preferably 0.2~1µm; the whisker-type reinforcing phase preferably includes one or more of ceramic whisker-type reinforcing phases and metal whisker-type reinforcing phases; the ceramic whisker-type reinforcing phase preferably includes oxide whiskers and non-oxide whiskers; the oxide whiskers preferably include Al2O3 or BeO; the non-oxide whiskers preferably include one or more of SiC, Si3N4, and SiN; the metal whisker-type reinforcing phase preferably includes one or more of Cu whiskers, Cr whiskers, Fe whiskers, and Ni whiskers. In this invention, the diameter of the particulate reinforcing phase is preferably less than 50 µm; the composition of the particulate reinforcing phase preferably includes one or more of Al2O3, SiC, TiC, B4C, TiB2, BN, AlN, Si3N4, NbN, SiO2, VC, WC, ZrC, ZrB2, ZrO2, MgO, MoSi2, Mo2C, MoS2, and YAl2.

[0034] Example 2: Based on Example 1, the powder blowing tube 306 is an irregularly shaped tubular structure with a round front end and a flat rear end, such as... Figure 3 As shown, the front end of the powder blowing tube 306 near the powder blowing cylinder 302 is round, while the rear end used for powder dispensing is flat.

[0035] Example 3: Based on Example 1, the powder distribution wheel groove 301 has several uniformly distributed grooves for storing a fixed amount of reinforcing phase powder. Figure 4 , Figure 5 As shown, different numbers of toothed grooves in the powder distribution wheel groove 301 can provide different powder feeding amounts, corresponding to different powder feeding rates. Powder from the powder storage bin 305 falls into the toothed grooves of the powder distribution wheel groove 301. The third motor 304 is started to control the rotation of the powder distribution wheel groove 301. Each time the powder distribution wheel groove 301 rotates by one scale, a certain amount of reinforcing phase powder will fall from the toothed grooves into the powder blowing cylinder 302.

[0036] The powder separator groove 301 and the powder storage bin 305 form a sealed connection. The reinforcing phase powder enters the powder blowing cylinder 302 from the powder storage bin 305. It can only be carried into the powder blowing cylinder 302 through the tooth groove by the rotation of the powder separator groove 301. It cannot leak in through the front and rear ends, sides, etc. of the powder separator groove 301.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A friction extrusion apparatus for metal matrix composites with an online reinforcing phase, characterized in that, It includes a spindle rotation and lifting assembly and a die assembly located in the moving extrusion direction of the spindle rotation and lifting assembly. The two work together for the preparation of composite materials by mixing metal substrate and reinforcing phase powder and friction extrusion. It also includes a powder feeding assembly, which uses inert gas to quantitatively and segmentally blow the reinforcing phase powder into the mold assembly.

2. The friction extrusion device for introducing a reinforcing phase online in a metal matrix composite material according to claim 1, characterized in that: The spindle rotation and lifting assembly includes a bracket, on which a spindle box is mounted, and the spindle box is connected to the bracket via a lifting structure. The lifting structure includes a lead screw, one end of which is connected to the output end of the first motor, and the other end of which is rotatably connected to the bracket. A nut seat is fitted on the lead screw, and the nut seat is threadedly connected to the lead screw. The nut seat is fixedly connected to the main shaft box. The lead screw has a guide rail fixed to the bracket on its side, and a movable slider is slidably mounted on the guide rail. The movable slider is fixedly connected to the spindle box.

3. The friction extrusion device for introducing a reinforcing phase online in a metal matrix composite material according to claim 2, characterized in that: The spindle box contains a spindle, one end of which is connected to the drive structure, and the other end of which is rigidly connected to the stirring head. The drive structure includes a first pulley coaxially connected to the end of the main shaft away from the stirring head, a second motor mounted on the main shaft box, the output shaft of the second motor connected to the second pulley, the second pulley being rotatably mounted on the main shaft box, and the second pulley being connected to the first pulley via a transmission belt.

4. The friction extrusion device for introducing a reinforcing phase online in a metal matrix composite material according to claim 3, characterized in that: The mold assembly includes a mold base, on which a cavity plate is provided. The cavity plate is provided with a feed groove and a cavity. The feed groove is distributed along the circumference of the cavity and communicates with the cavity. The feed groove is used to push the metal substrate into the cavity so that it contacts the stirring head.

5. The friction extrusion device for introducing a reinforcing phase online in a metal matrix composite material according to claim 4, characterized in that: The stirring head is aligned with the cavity, and a stirring pin is provided at the end of the stirring head. The outer wall of the stirring pin is machined with a left-hand thread. A clamping handle is provided at the end of the stirring head away from the stirring pin, and the clamping handle is rigidly connected to the main shaft.

6. The friction extrusion device for introducing a reinforcing phase online in a metal matrix composite material according to claim 1, characterized in that: The powder feeding assembly includes a powder storage bin, the top of which is set as a feeding opening. Inside the powder storage bin, there is a rotating powder distribution wheel groove located below the opening. A third motor is installed on the outside of the powder storage bin, and the output shaft of the third motor is connected to the powder distribution wheel groove. Below the powder distribution wheel groove, there is a powder blowing cylinder, and a powder blowing pipe is connected to the powder blowing cylinder. The powder blowing pipe is used to blow the reinforcing phase powder into the mold cavity.

7. The friction extrusion apparatus for introducing a reinforcing phase online in a metal matrix composite material according to claim 6, characterized in that: The powder separator has several uniformly sized grooves evenly distributed on its grooves, which are used to store a fixed amount of reinforcing phase powder.

8. The friction extrusion apparatus for introducing a reinforcing phase online in a metal matrix composite material according to claim 7, characterized in that: The powder blowing tube is an irregularly shaped tubular structure with a round front end and a flat rear end. The front end of the powder blowing tube near the powder blowing cylinder is round, and the rear end used for powder discharge is flat.

9. A method for friction extrusion of a metal matrix composite material with an online reinforcing phase according to any one of claims 1-8, characterized in that, Includes the following steps: Step 1: Start the first motor and the second motor. The first motor drives the stirring head to descend to the preset working position, and the second motor drives the stirring head to rotate at high speed. Step 2: Push the metal substrate into the cavity so that it comes into contact with the high-speed rotating stirring head and undergoes friction extrusion processing; Step 3: After the processing condition stabilizes, start the third motor to drive the powder distribution wheel groove to rotate, and quantitatively distribute the reinforcing phase powder in the powder storage bin into the powder blowing cylinder; Step 4: Quickly raise the stirring head to the preset powder feeding position away from the mold cavity, and at the same time introduce inert protective gas into the powder blowing tube to send the reinforcing phase powder into the mold cavity through the powder blowing tube. Step 5: Quickly lower the stirring head back to the preset working position and apply additional extrusion pressure to push the material out of the cavity. Step six involves the rapid reciprocating lifting and lowering of the stirring head, quantitative distribution of powder by the powder distribution wheel groove, and segmented powder feeding to complete the friction extrusion preparation of the entire metal matrix composite material.

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