Friction stir additive manufacturing device and method

Abstract

The invention discloses a stirring friction additive manufacturing device and method, relates to the technical field of additive manufacturing, and aims at solving the problems that in existing additive manufacturing, reinforced phases are not evenly distributed, an additive device is prone to being abraded, and the performance of a deposited material is degraded The device partially comprises a stirring head, a follow-up sleeve, a liquid cooling pipe and a metal matrix composite raw material rod. The follow-up sleeve is nested on the outer side of the stirring head, the liquid cooling pipe is used for continuously cooling and controlling the temperature of an additive tool and is mounted on the outer wall of the follow-up sleeve, the metal matrix composite raw material rod is fed to the stirring head, and pre-mixed powder of gel and a corrosion inhibitor is added into the metal matrix composite raw material rod to be combined with the metal slim pipe, so that the additive tool can be continuously stirred. The problem of uniform distribution of the reinforced phase of the aluminum-based composite material is solved, and meanwhile, the corrosion-resistant design of the deposited material is realized. The method is wide in application range, and can be suitable for reliable solid-phase deposition manufacturing of various low-volume-fraction metal-based composite materials such as aluminum-based, magnesium-based, copper-based and zinc-based composite materials.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and particularly to a friction stir additive manufacturing device and method. Background Art

[0002] As an important structural material in the modern industrial field, metal matrix composites have always guided the development direction of materials science with their lightweight and functional characteristics. In typical application scenarios such as aeroengine blades, satellite load-bearing frames, and new energy vehicle battery trays, low volume fraction lightweight alloy matrix composites exhibit unique application values. Such materials usually use lightweight metals such as aluminum alloys and magnesium alloys as the matrix, and by introducing a small amount of ceramic particles or fibers (such as silicon carbide, titanium diboride, etc.), carbonaceous nano-phases (such as graphene, carbon nanotubes, etc.) as reinforcements, on the basis of maintaining the excellent plasticity and toughness of the matrix material, significantly improve its strength, stiffness, and wear resistance. Taking aluminum matrix composites as an example, when the volume fraction of the reinforcement phase is controlled at 5% - 15%, its specific strength can reach more than 1.5 times that of traditional aluminum alloys, while the density only increases by 3% - 8%. This "using a little to move a lot" material design concept perfectly fits the extreme pursuit of structural efficiency in modern equipment manufacturing.

[0003] Currently, the industrial processing and preparation of such materials still mainly rely on traditional casting and powder metallurgy technologies. Although the casting method has the advantages of short process flow and low cost, in the actual production process, the interfacial reaction between molten metal and the reinforcement phase often leads to problems such as reinforcement particle agglomeration and matrix oxidation. Although powder metallurgy technology can better control the microstructure, its complex preparation process has caused a sharp rise in material costs, severely restricting its industrial application. More notably, both of these traditional processes have obvious limitations in manufacturing complex structural parts - the casting method is difficult to form thin-walled cavity structures, and powder metallurgy is limited by the mold size, which directly results in the inability to implement many theoretically feasible lightweight design schemes.

[0004] Facing the urgent demand for integrated forming of complex components in the high-end equipment field, additive manufacturing technology naturally becomes an important breakthrough to break through the bottlenecks of traditional manufacturing. However, existing metal additive manufacturing technologies face severe challenges when dealing with metal matrix composites: Processes based on the melting and solidification mechanism such as selective laser melting (SLM), the instantaneous high temperature will cause decomposition reactions of ceramic reinforcement phases such as silicon carbide. Research shows that when SLM is used to form AlSi10Mg / SiC composites, brittle phases such as Al4C3 are detected inside the material, resulting in a 62% decrease in elongation; Although the electron beam fused deposition (EBF) technology can reduce the heat input, the requirement of the vacuum environment greatly increases the equipment complexity. When this technology is used for a certain aerospace component, the single-piece man-hour cost increases by 3.8 times. These technical defects make it difficult for traditional additive manufacturing to meet the stringent requirements of metal matrix composites for tissue properties, forcing researchers to turn their attention to the emerging field of solid-phase additive manufacturing.

[0005] As a typical representative of solid-phase additive technology, friction stir additive manufacturing (FSAM) provides a new idea for solving the above problems with its low-temperature processing characteristics. This technology uses the frictional heat generated by the rotation of the stirring head to bring the material to a thermoplastic state, and realizes layer-by-layer stacking forming on the premise of avoiding metal melting. Existing research shows that for aluminum alloys formed by FSAM, the grain size can be refined to 1-5μm, and the mechanical properties reach the level of forgings of similar materials. However, when this technology is applied to metal matrix composites, there are still many technical difficulties to be overcome: The dynamic distribution mechanism of the reinforcement phase during the stirring process is not clear, and the coupling relationship between process parameters and material flow lacks systematic research. Most existing equipment directly uses traditional friction stir welding machines, which have obvious deficiencies in aspects such as reinforcement phase distribution control and interlayer temperature control; More critically, the conventional stirring head design is difficult to adapt to the special rheological characteristics of composites, and the wear rate of the stirring pin caused by silicon carbide particles increases by 7 times, seriously affecting the stability of the forming quality.

[0006] Deeply analyzing the technical essence of this contradiction, it can be found that solid-phase additive manufacturing of metal matrix composites needs to break through technical barriers in three dimensions:

[0007] (1) At the level of uniform distribution of the reinforcement phase, it is necessary to regulate the spatial distribution uniformity of the reinforcement phase through the design of the raw material form;

[0008] (2) At the level of the additive device, it is necessary to develop special additive tool components to solve the problems of tool wear and thermal cycle fluctuations caused by the reinforcement phase while realizing dense deposition of the material;

[0009] (3) In the material property method, it is necessary to solve the problem that the galvanic couple in the composite material seriously weakens the corrosion resistance of the material. Current domestic and foreign research mostly focuses on the improvement of single technical links, but there is always a lack of systematic solutions. This fragmented technical accumulation is difficult to meet the strict requirements of engineering applications for the consistency of forming quality, resulting in many laboratory achievements being limited to paper data and unable to be transformed into actual productivity.

[0010] In summary, in the face of such industry pain points, it is urgent to develop friction stir additive manufacturing technology dedicated to metal matrix composites. This not only concerns the innovation and breakthrough of individual process equipment, but also an important opportunity to promote the transformation of the entire material processing technology paradigm. In view of this, if a friction stir additive manufacturing device that can simultaneously break through the technical barriers in the above three dimensions can be designed, and a method suitable for reliable solid-phase additive manufacturing of metal matrix composites is proposed, it will effectively promote the industrial application of low-volume fraction metal matrix composites and achieve breakthroughs in their applications in aerospace, rail transit and other fields. Summary of the Invention

[0011] The present invention aims to solve the problems existing in the existing additive manufacturing, such as uneven distribution of reinforcement phases, easy wear of the additive manufacturing device, and deterioration of the properties of the deposited material, and further provides a friction stir additive manufacturing device and method.

[0012] The technical solutions adopted by the present invention to solve the above problems are as follows:

[0013] A friction stir additive manufacturing device of the present invention includes a stirring head, a follower sleeve, a liquid cooling pipe, and a metal matrix composite raw material rod. The follower sleeve is nested outside the stirring head. The stirring head is composed of a first clamping portion, a transition portion, a feeding screw portion, and a stirring pin portion connected in sequence from top to bottom. The follower sleeve includes a second clamping portion and a stationary shoulder. The clamping portion is used to connect with the rotating main shaft stator of the machining equipment. The stationary shoulder is a hollow cylindrical structure, and two side shaft feeding holes are provided on the outer wall for the continuous feeding of the metal matrix composite raw material rod. The end shoulder plane of the stationary shoulder is flush with the root of the stirring pin portion. The spiral liquid cooling pipe is wound around the outer wall of the stationary shoulder.

[0014] Further, a single-head rectangular spiral groove is provided on the feeding screw portion, and its pitch gradually decreases from top to bottom. The upper pitch is 20 - 40 mm, the lower pitch is 10 - 20 mm, and the total number of turns is 2.5 - 5.0 turns.

[0015] Further, the stirring pin portion is an eccentric frustum-shaped protrusion, the eccentricity is 0.2 - 0.4 times the diameter of the feeding screw portion, the diameter of the stirring pin portion is 0.2 - 0.3 times the diameter of the feeding screw portion, and the length is 1.5 - 2.5 times the thickness of the deposited layer.

[0016] Furthermore, the diameter of the side-axis feeding hole is 0.5 - 1.5 mm larger than the diameter of the metal matrix composite material raw material rod; a spiral circular groove is provided on the outer surface of the stationary shaft shoulder for brazing and installing a liquid cooling pipe.

[0017] The friction stir additive manufacturing method of the present invention is carried out according to the following steps:

[0018] S1: Preparation of metal matrix composite material powder:

[0019] Take a certain amount of metal powder and reinforcing phase powder, use isopropyl alcohol or acetone as a dispersant, and uniformly mix them for 30 minutes to 20 hours under the action of wet ball milling or ultrasonic dispersion. After filtration, dry them in a vacuum drying oven to make a uniformly dispersed metal matrix composite material powder;

[0020] S2: Preparation of metal matrix composite material gel:

[0021] Take all the metal matrix composite material powder, use deionized water as a solvent, weigh a certain amount of gelling agent and corrosion inhibitor and mix them in proportion, and make a metal matrix composite material gel under the action of mechanical stirring;

[0022] S3: Forming of metal matrix composite material raw material rod:

[0023] Fill the metal matrix composite material gel into the metal thin tube by means of negative pressure suction or positive pressure injection, and then place the metal thin tube in a vacuum drying oven for drying to make a metal matrix composite material raw material rod for friction stir additive manufacturing;

[0024] S4: Additive deposition forming:

[0025] Start the additive manufacturing tool, where the stirring head rotates at a high speed of 100 - 1500 rpm rotation speed ω and moves along the deposition path at a traveling speed v of 50 - 3000 mm / min; the follower sleeve follows the stirring head synchronously but does not rotate, and the metal matrix composite material raw material rod is fed into the feeding screw part of the stirring head along the side-axis feeding hole of the stationary shaft shoulder of the follower sleeve at a feeding speed f of 0.1 - 15 m / min, and moves downward to the vicinity of the stirring needle part under the extrusion of the feeding screw part, and is deposited and formed under the friction stir of the stirring needle part and the shaft shoulder plane of the stationary shaft shoulder.

[0026] Furthermore, in step 2, the components of the gelling agent used to prepare the metal matrix composite material gel include but are not limited to sodium alginate, sodium silicate, and polyethylene glycol.

[0027] Furthermore, when sodium alginate or sodium silicate is selected, the gel is directly cured by drying, and when polyethylene glycol is selected, the metal matrix composite material raw material rod injected with the gel needs to be placed in an environment of 350 °C for 1 - 2 hours to thermally decompose and volatilize it for removal.

[0028] Further, the corrosion inhibitors used for preparing the metal matrix composite gel include, but are not limited to, sodium molybdate, sodium tungstate, sodium hexametaphosphate, sodium tripolyphosphate, and sodium gluconate, among which the composite formula of sodium molybdate and sodium hexametaphosphate is used as the corrosion inhibitor.

[0029] The beneficial effects of the present invention are as follows:

[0030] 1. In the present invention, a spiral groove with a gradually decreasing pitch from top to bottom is provided in the screw part. Due to the gradually decreasing pitch, the volume of the raw material shrinks and densification occurs, ensuring the dense forming of the material. At the same time, due to the volume reduction caused by the gradually decreasing pitch, the dried metal matrix composite gel filled in the metal matrix composite raw material rod gradually shrinks in the metal fine tube, avoiding its direct contact with the feeding screw part, thereby avoiding the wear of the reinforcing phase on the matrix.

[0031] 2. In the present invention, continuous cooling and temperature control of the additive manufacturing tool are achieved by cooling deionized water with a liquid cooling tube, avoiding overheating and unexpected temperature fluctuations during the additive manufacturing process.

[0032] 3. In the present invention, by adding a combination of a premixed powder of a gelling agent and a corrosion inhibitor in the metal matrix composite raw material rod and a metal fine tube, the problem of uniform distribution of the reinforcing phase in the aluminum matrix composite is solved, and at the same time, the corrosion resistance design of the deposited material is realized.

[0033] 4. The present invention has a wide range of applications and can be applied to the reliable solid-phase deposition manufacturing of various low-volume fraction metal matrix composites, such as aluminum matrix, magnesium matrix, copper matrix, zinc matrix composites, etc. Brief Description of the Drawings

[0034] Figure 1 is the working principle diagram of a friction stir additive manufacturing device and method according to the present invention;

[0035] Figure 2 is the additive manufacturing tool structure diagram of a friction stir additive manufacturing device and method according to the present invention;

[0036] Figure 3 is the stirring head structure diagram of a friction stir additive manufacturing device and method according to the present invention;

[0037] Figure 4 is the follower sleeve structure diagram of a friction stir additive manufacturing device and method according to the present invention;

[0038] Figure 5 is the method flow diagram of a friction stir additive manufacturing device and method according to the present invention.

[0039] 1 - Stirring head, 101 - Clamping part, 102 - Transition part, 103 - Feeding screw part, 104 - Stirring pin part;

[0040] 2 - Follow - up sleeve, 201 - Clamping part, 202 - Static shaft shoulder, 20201 - Side shaft feeding hole, 20202 - Spiral circular groove, 20203 - Shaft shoulder plane;

[0041] 3 - Liquid cooling tube;

[0042] 4 - Metal matrix composite material raw rod;

[0043] 5 - Deposition component. Specific implementation mode

[0044] Specific implementation mode one: Combined with Figures 1 to 4 To illustrate this implementation mode, a friction stir additive manufacturing device described in this implementation mode, as Figures 1-2 shown, includes a stirring head 1, a follow - up sleeve 2, a liquid cooling tube 3 and a metal matrix composite material raw rod 4. The follow - up sleeve 2 is nested outside the stirring head 1.

[0045] As Figure 3 shown, the stirring head 1 includes a first clamping part 101, a transition part 102, a feeding screw part 103 and a stirring pin part 104. The first clamping part 101, the transition part 102, the feeding screw part 103 and the stirring pin part 104 are connected in sequence from top to bottom. Among them, the clamping part 101 is used to be connected to the rotating spindle rotor part of machining equipment including but not limited to friction stir welding machines, CNC milling machines, CNC machining centers, etc., and is provided with a side milling plane for side - fixed clamping.

[0046] The transition part 102 is used to connect the clamping part 101 and the feeding screw part 103, and there is a shaft shoulder surface between it and the clamping part 101 for the axial positioning of the stirring head.

[0047] The feeding screw part 103 is a cylindrical structure, and is provided with a single - start rectangular spiral groove with a pitch gradually decreasing from top to bottom. Its total number of turns is 2.5 - 5.0 turns, the upper pitch is 20 - 40 mm, and the lower pitch is 10 - 20 mm. The lower pitch should not be less than 1.5 times the diameter of the metal matrix composite material raw rod 4. During the deposition process of the metal matrix composite material, the additive raw material moves downward under the action of screw conveying. Due to the gradually decreasing pitch, the volume of the raw material shrinks and densification occurs, ensuring the dense forming of the material. At the same time, due to the volume reduction caused by the gradually decreasing pitch, the dried metal matrix composite gel filled in the metal matrix composite material raw rod 4 gradually shrinks proportionally in the metal fine tube, avoiding its direct contact with the feeding screw part 103, thereby avoiding the wear of the reinforcement on the matrix.

[0048] The stirring needle part 104 is a frustum-shaped protrusion arranged eccentrically. Its eccentricity is usually 0.2 to 0.4 times the diameter of the feeding screw part 103, the diameter is usually 0.2 to 0.3 times the diameter of the feeding screw part 103, and the length is 1.5 to 2.5 times the thickness of the deposition layer 5, so as to ensure the stirring effect on the deposition layer 5 of solid-phase additive manufacturing and improve the interfacial bonding strength.

[0049] As Figure 4 shown, the follower sleeve 2 includes a second clamping part 201 and a stationary shaft shoulder 202; the clamping part 201 is used to be connected to the rotating spindle stator part of machining equipment including but not limited to friction stir welding machines, CNC milling machines, and CNC machining centers. It is provided with an annular protrusion and a shaft shoulder surface to ensure its coaxial positioning and axial positioning with the stirring head 1. After installation, the end 20203 of its stationary shaft shoulder should be flush with the root of the stirring needle part 104 of the stirring head.

[0050] The stationary shaft shoulder 202 is a hollow cylindrical structure, provided with two side shaft feeding holes 20201 for the continuous feeding of the metal matrix composite material raw material rod. Its diameter should be slightly larger than the diameter of the metal matrix composite material raw material rod 4 by 0.5 to 1.5 mm. A spiral circular groove 20202 is provided on the outer surface for brazing and installing the liquid cooling pipe 3 to achieve precise temperature control during the additive manufacturing process. Its end is a stationary shaft shoulder plane 20203 with a chamfer, which is used to restrain the additive material during the additive manufacturing process and mill the surface of the deposition body 5 to achieve the dense forming of the component. During the entire deposition work, the follower sleeve 2 travels synchronously with the stirring head 1 but does not rotate.

[0051] As Figure 2 shown, the liquid cooling pipe 3 is a copper hollow circular pipe wound around the surface of the follower sleeve. It is fixedly connected to the spiral circular groove 20202 on the surface of the stationary shaft shoulder of the follower sleeve by brazing. During the friction stir additive manufacturing process, cooling deionized water is passed through it to continuously cool and control the temperature of the additive tool, avoiding overheating and unexpected temperature fluctuations during the additive manufacturing process.

[0052] As Figure 1 shown, the metal matrix composite material raw material rod 4 is a metal circular pipe containing dried metal matrix composite material gel. Its outer diameter is usually 3 to 8 mm. The material of the metal circular pipe should be roughly the same as the composition of the metal powder in the metal matrix composite material gel. The volume fraction of the reinforcing phase of this raw material rod can be calculated by the ratio of the volume of the reinforcing phase in the metal matrix composite material powder to the total volume after the metal matrix composite material raw material rod is compacted. The metal matrix composite material gel in the metal matrix composite material raw material rod contains a gelling agent and a corrosion inhibitor. During the service process of the deposited component made of it, a protective corrosion inhibition layer will be slowly released on the surface, thereby inhibiting the microgalvanic corrosion tendency of the composite material itself and improving the corrosion resistance of the material.

[0053] Specific Embodiment 2: As Figure 1 , Figure 5 shown, this embodiment is a friction stir additive manufacturing method, and its specific method is as follows:

[0054] S1: Take a certain amount of metal powder and reinforcing phase powder, use isopropyl alcohol or acetone as a dispersant, and uniformly mix them for 30 minutes to 20 hours under the action of wet ball milling or ultrasonic dispersion. After filtration, dry them in a vacuum drying oven to make a uniformly dispersed metal matrix composite powder;

[0055] S2: Take all the metal matrix composite powder, use deionized water as a solvent, weigh a certain amount of gelling agent and corrosion inhibitor and mix them in proportion, and make a metal matrix composite gel under the action of mechanical stirring;

[0056] S3: Fill the metal matrix composite gel into a metal capillary by means of negative pressure suction or positive pressure injection, and then place the metal capillary in a vacuum drying oven for drying to make a metal matrix composite raw material rod 5 for friction stir additive manufacturing;

[0057] S4: Start the additive manufacturing tool, where the stirring head 1 rotates at a high speed ω of 100 - 1500 rpm and moves along the deposition path at a traveling speed v of 50 - 3000 mm / min. The follower sleeve 2 does not rotate but follows the stirring head 1 synchronously. The metal matrix composite raw material rod 5 is fed into the stirring head feeding screw part 103 through the feeding hole 20201 on the side of the stationary shaft shoulder of the follower sleeve along the axis at a feeding speed f of 0.1 - 15 m / min, and moves downward to near the stirring pin part 104 under the extrusion of the feeding screw part 103, and is deposited and formed under the friction stir of the stirring pin part 104 and the stationary shaft shoulder plane 20203.

[0058] Specific Embodiment 3: This embodiment is a friction stir additive manufacturing method. The purpose of the gelling agent used to prepare the metal matrix composite gel is to avoid uneven distribution or flow after it is injected into the metal capillary and improve the tissue uniformity of the deposited component. Its components include but are not limited to sodium alginate, sodium silicate, polyethylene glycol, etc. Among them, sodium alginate, sodium silicate, etc. do not require special treatment to be removed during the subsequent drying process, and polyethylene glycol requires placing the metal matrix composite raw material rod injected with the gel in an environment of 350 °C for 1 - 2 hours to pyrolyze and volatilize it for removal.

[0059] Specific Embodiment 4: This embodiment is a friction stir additive manufacturing method. The corrosion inhibitors used to prepare the metal matrix composite gel include but are not limited to sodium molybdate, sodium tungstate, sodium hexametaphosphate, sodium tripolyphosphate, sodium gluconate, etc. Among them, the composite formula of sodium molybdate and sodium hexametaphosphate is preferably used as the corrosion inhibitor.

[0060] Specific Embodiment 5: This embodiment is a friction stir additive manufacturing method. If there are problems with the deposition forming of metal matrix composites, optionally, 1-20% by mass of silicon powder and zinc powder are mixed into the metal powder to enhance the fluidity of the additive raw material at the thermoplastic temperature and improve the forming quality.

[0061] The above are only the preferred embodiments of the present invention and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications into equivalent embodiments using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the technical solution content of the present invention and is based on the technical essence of the present invention, any simple modification, equivalent replacement, and improvement made to the above embodiments within the spirit and principle of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A friction stir additive manufacturing device, characterized in that: It includes a stirring head (1), a follower sleeve (2), a liquid cooling pipe (3) and a metal matrix composite material raw material rod (4). The follower sleeve (2) is nested outside the stirring head (1). The stirring head (1) is successively connected from top to bottom by a first clamping portion (101), a transition portion (102), a feeding screw portion (103) and a stirring pin portion (104). The follower sleeve (2) includes a second clamping portion (201) and a stationary shaft shoulder (202). The clamping portion (201) is used to connect with the rotating main shaft stator of the machining equipment. The stationary shaft shoulder (202) is a hollow cylindrical structure, and two side shaft feeding holes (20201) are arranged on the outer wall for the continuous feeding of the metal matrix composite material raw material rod (4). The end shaft shoulder plane (20203) of the stationary shaft shoulder (202) is flush with the root of the stirring pin portion (104). The spiral liquid cooling pipe (3) is wound around the outer wall of the stationary shaft shoulder (202).

2. The friction stir additive manufacturing device according to claim 1, characterized in that: The feeding screw portion (103) is provided with a single-start rectangular spiral groove, the pitch of which gradually decreases from top to bottom. The upper pitch is 20 - 40 mm, the lower pitch is 10 - 20 mm, and the total number of turns is 2.5 - 5.0 turns.

3. The friction stir additive manufacturing device according to claim 1, wherein: The stirring pin portion (104) is an eccentric frustum-shaped protrusion, the eccentricity of which is 0.2 - 0.4 times the diameter of the feeding screw portion (103). The diameter of the stirring pin portion (104) is 0.2 - 0.3 times the diameter of the feeding screw portion (103), and the length is 1.5 - 2.5 times the thickness of the deposition layer (5).

4. The friction stir additive manufacturing device according to claim 1, characterized in that: The diameter of the side shaft feeding hole (20201) is 0.5 - 1.5 mm larger than the diameter of the metal matrix composite material raw material rod (4). A spiral circular groove (20202) is arranged on the outer surface of the stationary shaft shoulder (202) for brazing and installing the liquid cooling pipe (3).

5. A friction stir additive manufacturing method according to claim 1, characterized in that: The method is carried out according to the following steps: S1: Preparation of metal matrix composite powder: Take a certain amount of metal powder and reinforcing phase powder, use isopropyl alcohol or acetone as a dispersant, and uniformly mix them under the action of wet ball milling or ultrasonic dispersion for 30 minutes to 20 hours. After filtration, dry them in a vacuum drying oven to make a uniformly dispersed metal matrix composite powder. S2: Preparation of metal matrix composite gel: Take all the metal matrix composite powder, use deionized water as a solvent, weigh a certain amount of gelling agent and corrosion inhibitor and mix them in proportion, and make a metal matrix composite gel under the action of mechanical stirring. S3: Molding of metal matrix composite material raw material rod: Fill the metal matrix composite gel into a metal thin tube by means of negative pressure suction or positive pressure injection, and then place the metal thin tube in a vacuum drying oven to dry it to make a metal matrix composite material raw material rod (4) for friction stir additive manufacturing. S4: Additive deposition molding: Start the additive manufacturing tool, where the stirring head (1) rotates at a high speed with a rotational speed ω of 100 - 1500 rpm and moves along the deposition path at a traveling speed v of 50 - 3000 mm / min; the follower sleeve (2) follows the stirring head (1) synchronously but does not rotate, and the metal matrix composite material raw material rod (5) is fed into the feeding screw part (103) of the stirring head along the feeding hole (20201) on the side of the stationary shaft shoulder of the follower sleeve at a feeding speed f of 0.1 - 15 m / min, and moves downward to the vicinity of the stirring needle part (104) under the extrusion of the feeding screw part (103), and is deposited and formed under the friction stir of the stirring needle part (104) and the friction stir plane of the stationary shaft shoulder (20203).

6. The friction stir additive manufacturing device according to claim 1, wherein: In step 2, the gelling agent components used to prepare the metal matrix composite gel include, but are not limited to, sodium alginate, sodium silicate, and polyethylene glycol.

7. The friction stir additive manufacturing device according to claim 6, characterized in that: When sodium alginate or sodium silicate is selected, the gel is directly cured by drying, and when polyethylene glycol is selected, the metal matrix composite material raw material rod (4) injected with the gel needs to be placed in an environment of 350 °C for 1 - 2 hours to thermally decompose and volatilize and remove it.

8. The friction stir additive manufacturing device according to claim 1, characterized in that: The corrosion inhibitors used to prepare the metal matrix composite gel include, but are not limited to, sodium molybdate, sodium tungstate, sodium hexametaphosphate, sodium tripolyphosphate, and sodium gluconate, and the composite formula of sodium molybdate and sodium hexametaphosphate is used as the corrosion inhibitor.

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