A heterogeneous mixing feed based friction stir deposition apparatus and method of use

Abstract

This invention discloses a stirring friction deposition apparatus based on heterogeneous mixed feeding, comprising a tapered screw, a stationary shoulder, and a feeding device. The tapered screw includes a main shaft clamping part, a screw feeding section, a screw compression section, a screw metering section, and threads. The stationary shoulder includes a stationary shoulder clamping part, a feeding port, and a discharging port. The stationary shoulder is installed on a stationary shoulder chuck so that the stationary shoulder does not participate in rotation. The tapered screw fits inside the stationary shoulder, and the gap between the tapered screw and the stationary shoulder forms a grinding space for the raw material. The feeding port cooperates with the feeding device to feed the raw material into the grinding space. This invention can realize in-situ alloying in solid-phase additive manufacturing processes, avoiding problems such as porosity, cracks, and residual stress caused by the melting-solidification process. It can prepare traditional alloy components by mixing pure metal powder and alloy powder, and can also prepare heterogeneous structures with alternating coarse and fine grains and reinforcing phases by attaching alloy powder to metal particles.

Description

Technical Field

[0001] This invention belongs to the field of additive manufacturing technology, specifically relating to a stirring friction deposition device and its usage method based on heterogeneous mixed feeding. Background Technology

[0002] With the development of aerospace, biomedicine, and modern transportation, the demand for metallic materials with high strength, toughness, lightweight, and functional properties (such as high-performance alloys and metal matrix composites) is becoming increasingly urgent. Traditional preparation methods (such as smelting and casting) suffer from problems such as coarse grains, compositional segregation, high energy consumption, and easy casting defects. Although current additive manufacturing technologies (such as laser / electronic powder bed melting, i.e., 3D printing) can manufacture complex shapes and structures, their rapid melting and solidification process easily leads to high residual stress, hot cracking tendency, and deterioration of the microstructure in the heat-affected zone. Furthermore, during the melting process of metal matrix composite powder, the reinforcing phase usually exists in the solid phase, which has poor wettability. During additive manufacturing, it is easy to cause weak bonding and uneven distribution between the reinforcing phase and the metal matrix. In addition, during in-situ alloying, the addition of certain low-melting-point, easily oxidized, or refractory heterogeneous elements can easily lead to the burning off or uneven distribution of alloying elements during melting and processing, making it difficult to achieve precise composition ratios.

[0003] Friction stir deposition (FSD), as an emerging solid-state additive manufacturing technology, achieves solid-state deposition of materials through intense plastic deformation and frictional heat generation. This effectively avoids metallurgical defects associated with melting and solidification, and achieves significant grain refinement. Furthermore, the strengthening phase in the solid state does not have wettability issues with the matrix, and under the strong thermal action of friction stir, it can form a high-strength bond with the matrix. However, existing FSD processes mostly use pre-fabricated rods or wires of a single component as raw materials. Pre-fabricated alloy or metal matrix composite rods / wires are not only complex and costly, but once prepared, the alloy composition during the deposition process cannot be flexibly customized. In addition, the microstructure of components obtained by existing FSD processes is mostly equiaxed crystal structure formed by dynamic recrystallization, and the strengthening form is relatively simple. Although the strength of the components is mostly higher than that of melting additive manufacturing, it is still difficult to further improve their strength and plasticity. Summary of the Invention

[0004] (1) Technical problems to be solved To address the shortcomings of existing technologies, the present invention aims to provide a stirring friction deposition apparatus and method based on heterogeneous mixed feed, which has the advantage of enabling in-situ alloying in solid-phase additive manufacturing processes.

[0005] (2) Technical solution To address the aforementioned technical problems, this invention provides a stirring friction deposition apparatus based on heterogeneous mixed feeding, comprising a tapered screw, a stationary shoulder, and a feeding device. The tapered screw is mounted on a rotating spindle and includes a spindle clamping portion, a screw feeding section, a screw compression section, a screw metering section, and threads. The stationary shoulder includes a stationary shoulder clamping portion, a feeding port, and a discharge port. The stationary shoulder is mounted on a stationary shoulder chuck so that it does not participate in rotation. The tapered screw fits inside the stationary shoulder, and the bottom surfaces of the tapered screw and the stationary shoulder are on the same plane. The gap between the tapered screw and the stationary shoulder forms a grinding space for the raw material. The feeding port cooperates with the feeding device to feed the raw material into the grinding space.

[0006] Preferably, the raw material forms include metal particles, powder, and metal particles with powder attached. The shape, size, and ratio of the particles and powder can be adjusted according to actual needs.

[0007] Furthermore, the feeding device is a vibrating feeding device, which feeds the raw material through the feeding port into the grinding space formed by the tapered screw and the stationary shoulder by vibrating and shaking the feeding pipe.

[0008] Furthermore, the feeding device is a screw feeding device, which feeds the raw material into the grinding space formed by the tapered screw and the stationary shoulder through the feeding port, and discharges the raw material after being processed by the tapered screw out of the grinding space through the discharge port.

[0009] Furthermore, the main shaft clamping part is connected to the rotating main shaft. The screw feeding section, screw compression section, and screw metering section all have threads and the same outer diameter. The screw feeding section has the smallest and consistent inner diameter. The screw compression section has an inner diameter that gradually increases from top to bottom along the axial direction. The screw metering section has the largest and consistent inner diameter. The inner diameter of the screw feeding section is the same as the inner diameter of the uppermost end of the screw compression section. The inner diameter of the screw metering section is the same as the inner diameter of the lowermost end of the screw compression section. The ratio of the distance between the outer diameter and inner diameter of the screw feeding section to the distance between the outer diameter and inner diameter of the screw metering section is called the compression ratio of the tapered screw.

[0010] A method of using a stirred friction deposition apparatus based on heterogeneous mixed feed includes the following steps: Step 1: Determine the form and proportion of raw materials: Based on the microstructure and performance requirements of the target additive component, determine the form of raw materials to be used, such as metal particles, powder, or metal particles with attached powder, and clarify their composition and proportion, and temporarily store them in a storage funnel. Step 2: Feed the raw materials into the grinding space: Select either a screw feeder or a vibrating feeder according to the suitability of the raw material form and feed the raw materials into the grinding space through the feed port; Step 3: Tapered screw extrusion of plasticized raw materials: The rotation of the main shaft drives the tapered screw to rotate. The raw material is transported downward through the screw feeding section. When it passes through the screw compression section, under the combined action of the inner wall of the stationary shaft shoulder and the screw compression section of the tapered screw, the raw material is subjected to severe shearing, extrusion and friction, and enters a continuous thermoplasticization state, finally obtaining continuous plasticized metal. The continuously extruded plasticized metal is discharged from the grinding space through the discharge port through the screw metering section. Step 4, Deposition Layer Formation: After the continuously extruded plasticized metal is discharged from the grinding space, a deposition layer is formed under the joint constraint of the substrate and the bottom surface of the deposition device; Step 5, Continuous Deposition Operation: With the help of a feeding device, continuous feeding can be used to achieve continuous deposition operation along a preset trajectory to additively manufacture specified components.

[0011] Furthermore, the raw material is composed of a combination of physical morphological characteristics and chemical composition characteristics, wherein the physical morphological characteristics are selected from at least one of particles, powders, and composite particles with powder adhering to their surface; the chemical composition characteristics are selected from at least one of pure metals, alloys, reinforcing phases, and metal matrix composites; and the specific form of the raw material is any combination of any of the above physical morphological characteristics and any of the chemical composition characteristics. The reinforcing phase includes, but is not limited to, carbides, oxides, nitrides, carbon group materials, and intermetallic compounds.

[0012] Furthermore, the metal particles in step one are pure metal particles or alloy particles; The shape and size of the particles can be flexibly adjusted according to the requirements of the feeding device, deposition device and component structure and performance. The composition of the metal particles can be particles with one component or a mixture of two or more particle components. In step one, the powder is one or more of pure metal powder, alloy / metal matrix composite powder, and mixed powder of metal / alloy and reinforcing phase. The shape and size of the powder can be flexibly adjusted according to the requirements of the feeding device, deposition device and component microstructure and properties. The metal particles with powder attached to their surface in step one include, but are not limited to, pure metal particles with attached alloy powder, alloy particles with attached alloy powder, pure metal particles with attached reinforcing phase powder, and alloy particles with attached reinforcing phase powder.

[0013] Furthermore, in step three, the compression ratio and size of the tapered screw can be adjusted according to the mixing characteristics of the raw materials, the ease of plasticization, and the target microstructure.

[0014] Furthermore, in step five, the form and composition of the raw materials can be adjusted in situ to prepare functionally graded additive components with gradually changing microstructure and properties of each deposition layer during continuous deposition operations.

[0015] Beneficial effects Compared with the prior art, the beneficial effects of the present invention are as follows: This invention enables in-situ control of composition during solid-phase additive manufacturing, greatly simplifies the preparation process of raw materials in traditional solid-phase additive manufacturing, increases the flexibility of component structure and performance control, and provides a new method for the development and preparation of novel high-performance alloys, metal matrix composites, and functionally graded materials. This invention enables in-situ alloying during solid-phase additive manufacturing, avoiding problems such as porosity, cracks, and residual stress caused by the melting-solidification process. It can not only prepare traditional alloy components by mixing pure metal powder and alloy powder, but also prepare heterogeneous structures with alternating coarse and fine grains and reinforcing phases by attaching metal particles to alloy powder. It introduces multiple strengthening mechanisms on the basis of traditional fine grain strengthening to achieve synergistic improvement of strength and plasticity. This invention enables in-situ preparation of composite materials during solid-phase additive manufacturing. The solid-phase process with strong stirring friction successfully avoids the problems of wettability of the reinforcing phase and its weak bonding with the matrix. It can prepare metal matrix composites with uniform distribution of reinforcing phase in the traditional sense through powder mixing, or prepare heterogeneous structures with alternating distribution of coarse and fine grains and reinforcing phase by attaching reinforcing phase to the surface of metal particles, thereby achieving a synergistic improvement in the strength and plasticity of metal matrix composites. This invention has a wide range of applications, including additive manufacturing of high-strength components, additive manufacturing of functionally graded materials, in-situ strengthening of the repair zone during structural defect repair, and manufacturing of transition joints between dissimilar materials. The raw material composition of this invention can be flexibly controlled, which is more conducive to the integrated manufacturing of materials, microstructure, structure and function for the future. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention based on screw feeding; Figure 2 This is a schematic diagram of the overall structure of the present invention based on vibration feeding; Figure 3 This is a schematic diagram of a tapered screw structure; Figure 4 This is a schematic diagram of a stationary shoulder structure; Figure 5 This is a schematic diagram of the extrusion plasticization and deposition forming process of the material of this invention; Figure 6 These are related effect diagrams of the preparation of SiC-reinforced aluminum matrix composites in the embodiments of the present invention; Figure 7The figures show the effects of achieving in-situ alloying of pure zinc and obtaining a heterostructure in an embodiment of the present invention.

[0017] Among them, 1. Tapered screw; 2. Stationary shoulder; 3. Feeding device; 4. Component; 5. Base plate; 6. Vibrating feeding device; 7. Storage hopper; 8. Raw material; 101. Main shaft clamping part; 102. Screw feeding section; 103. Screw compression section; 104. Screw metering section; 105. Thread; 201. Shoulder clamping part; 202. Feed port; 203. Discharge port; 801. Plasticized metal. Detailed Implementation

[0018] The present invention provides a stirring friction deposition apparatus based on heterogeneous mixed feed, which is used in conjunction with a substrate 5.

[0019] In some embodiments, the deposition apparatus includes a tapered screw 1, a stationary shoulder 2, and a feeding device 3; the tapered screw 1 is mounted on a rotating spindle, and the rotating spindle drives the tapered screw 1 to rotate. The connection between the rotating spindle and the drive mechanism is prior art and will not be described in detail here.

[0020] In some embodiments, the tapered screw 1 includes a spindle clamping portion 101, a screw feeding section 102, a screw compression section 103, a screw metering section 104, and a thread 105. The spindle clamping portion 101 is connected to a rotating spindle. The screw feeding section 102, the screw compression section 103, and the screw metering section 104 all have threads 105 and the same outer diameter. The screw feeding section 102 has the smallest screw inner diameter, which remains consistent. The screw compression section 103 has a screw inner diameter that gradually increases from top to bottom along the axial direction. The screw metering section 104 has the largest screw inner diameter, which remains consistent. The inner diameter of the screw feeding section 102 is the same as the uppermost inner diameter of the screw compression section 103. The inner diameter of the screw metering section 104 is the same as the lowermost inner diameter of the screw compression section 103. The ratio of the distance between the outer diameter and the inner diameter of the screw feeding section 102 to the distance between the outer diameter and the inner diameter of the screw metering section 104 is called the compression ratio of the tapered screw 1.

[0021] In some embodiments, the stationary shoulder 2 includes a stationary shoulder clamping portion 201, a feeding port 202, and a discharging port 203. The stationary shoulder 2 is mounted on a stationary shoulder chuck so that the stationary shoulder 2 does not participate in rotation. The tapered screw 1 is fitted inside the stationary shoulder 2. The bottom surfaces of the tapered screw 1 and the stationary shoulder 2 are located on the same plane, and the gap between the tapered screw 1 and the stationary shoulder 2 forms a grinding space for the raw material. The feeding port 202 cooperates with the feeding device 3 to feed the raw material into the grinding space.

[0022] In some embodiments, the feeding device 3 is a screw feeding device. The screw feeding device feeds the raw material through the feeding port 202 into the grinding space formed by the tapered screw 1 and the stationary shoulder 2, and the discharge port 203 discharges the raw material after the action of the tapered screw 1 out of the grinding space. Specifically, the screw feeding device uses a motor to drive the feeding screw in the screw feeding device to feed the raw material 8 into the grinding space formed by the tapered screw 1 and the stationary shoulder 2.

[0023] In some other embodiments, the feeding device 3 is a vibrating feeding device 6, which feeds the raw material through the feeding port 202 into the grinding space formed by the tapered screw 1 and the stationary shoulder 2 by vibrating and shaking the feeding pipe.

[0024] In some embodiments, the bottom forming surfaces of the tapered screw 1 and the stationary shoulder 2 are both planar, used to provide upsetting pressure during the deposition process and prevent the plasticized metal 801 from being extruded in large quantities as flash, thereby achieving the smoothing of the repair surface.

[0025] In some embodiments, the raw material 8 may be in the form of metal particles, powder, or metal particles with powder attached, and the shape, size, and ratio of the particles and powder may be adjusted according to actual needs.

[0026] During the operation of this deposition apparatus, the rotation of the main shaft drives the tapered screw 1 to rotate. The raw material 8 is transported downward through the screw feeding section 102. When passing through the screw compression section 103, under the combined action of the inner wall of the stationary shoulder 2 and the screw compression section 103 of the tapered screw 1, the raw material 8 is subjected to severe shearing, extrusion and friction, and enters a continuous thermoplastic state to obtain continuous plasticized metal 801. The continuous plasticized metal 801 is discharged from the grinding space through the discharge port 203 by the screw metering section 104. After the continuous plasticized metal 801 is discharged from the grinding space, it forms a deposition layer under the joint constraint of the substrate 5 and the bottom surface of the deposition apparatus.

[0027] In the repair process, this application utilizes the rotation, friction, shearing, and extrusion of the tapered screw 1 to transfer the plasticizing process of metal particles from the traditional deposition device-substrate interface to the inside of the deposition device, thereby realizing in-situ alloying of the screw extrusion plasticizing process.

[0028] The present invention also provides a method for using a stirred friction deposition apparatus based on heterogeneous mixed feed, which is implemented based on the above-mentioned stirred friction deposition apparatus based on heterogeneous mixed feed, and includes the following steps: Step 1: Determine the form and composition ratio of raw material 8: Based on the microstructure and performance requirements of the target additive component, determine the form of raw material to be used, such as metal particles, powder, or metal particles with attached powder, and clarify its composition and proportion, and temporarily store it in the storage funnel 7. Step 2: Feed the raw material 8 into the grinding space: Select one of the feeding methods, either the screw feeder or the vibrating feeder 6, according to the applicability of the form of conveying the raw material 8, and feed the raw material 8 into the grinding space through the feeding port 202; Step 3: Extrusion of plasticized raw material by tapered screw 1: The rotation of the main shaft drives the tapered screw 1 to rotate. The raw material is transported downward through the screw feeding section 102. When passing through the screw compression section 103, under the combined action of the inner wall of the stationary shoulder 2 and the screw compression section 103 of the tapered screw 1, the raw material is subjected to severe shearing, extrusion and friction, and enters a continuous thermoplastic state to obtain continuous plasticized metal 801. The continuous plasticized metal 801 is discharged from the grinding space through the discharge port 203 through the screw metering section 104. Step 4, Deposition Layer Formation: After the continuous plasticized metal 801 is discharged from the grinding space, a deposition layer is formed under the joint constraint of the substrate 5 and the bottom surface of the deposition device. Step 5, Continuous deposition operation: With the continuous feeding of the feeding device 3, continuous deposition operation can be carried out according to the preset trajectory to additively manufacture the specified component 4.

[0029] In some embodiments, raw material 8 is composed of a combination of physical morphological characteristics and chemical composition characteristics; The physical morphological characteristics are selected from at least one of particles, powders, and composite particles with powder adhering to their surface. In addition, the chemical composition characteristics are selected from at least one of pure metals, alloys, reinforcing phases and metal matrix composites; the specific form of the raw material is any combination of any of the above physical morphological characteristics and any of the chemical composition characteristics. Reinforcing phases include, but are not limited to, carbides (such as silicon carbide, boron carbide, titanium carbide, etc.), oxides (alumina, silicon dioxide, zirconium dioxide, etc.), nitrides (silicon nitride, aluminum nitride, titanium nitride, etc.), carbon group materials (graphene, carbon nanotubes, diamond, etc.) and intermetallic compounds. The specific form of raw material 8 is any combination of any of the above-mentioned physical morphological characteristics and any of the chemical component characteristics.

[0030] In some embodiments, the metal particles in step one can be pure metal particles (including but not limited to pure metal particles such as Al, Mg, Zn, Cu, Ag, Au, Ti, etc.) or alloy particles (including but not limited to alloy particles such as Al, Mg, Zn, Cu, Ag, Au, Ti, etc.). The shape and size of the particles can be flexibly adjusted according to the requirements of the feeding device 3, the deposition device and the structure and properties of the components. The composition of the metal particles can be particles of one component or a mixture of two or more particle components. For example, a multi-material component component can be prepared by mixing multiple metal particles and then using this method.

[0031] In some embodiments, the powder in step one can be pure metal powder (including but not limited to pure metal particles such as Al, Mg, Zn, Cu, Ag, Au, Ti, etc.), alloy / metal matrix composite powder (including but not limited to alloy powders of Al, Mg, Zn, Cu, Ag, Au, Ti, etc. and composite powders with thereon as the matrix), or a mixture of metal / alloy and reinforcing phase. The shape and size of the powder can be flexibly adjusted according to the requirements of the feeding device 3, the deposition device and the structure and properties of the component. The powder composition in step one can be a single component or a mixture of two or more powder components. For example, high-entropy alloy components can be prepared by mixing multiple metal powders and then using this method.

[0032] In some embodiments, the metal particles with powder attached to their surface in step one include, but are not limited to, pure metal particles with attached alloy powder, alloy particles with attached alloy powder, pure metal particles with attached reinforcing phase powder, and alloy particles with attached reinforcing phase powder.

[0033] The raw material 8 uses metal particles with surface-attached powder, which have a high degree of flexibility in composition configuration. Specifically, the raw material 8 can contain only a single component combination (i.e., all matrix particles have the same composition and the surface-attached powder has the same composition) or it can be a mixture of multiple components in a certain proportion (i.e., the matrix particles have different compositions and the surface-attached powder has different compositions). By using such a multi-component particle mixing system, the present invention can effectively prepare alloy materials with complex heterogeneous structures.

[0034] In some embodiments, the preparation method of metal particles, powder, or metal particles with attached powder in step one includes, but is not limited to, ball milling, binder, oil adhesion, etc.

[0035] In some embodiments, in step three, the compression ratio and size of the tapered screw 1 can be adjusted according to the mixing characteristics of the raw material 8, the ease of plasticization, and the target microstructure.

[0036] In some embodiments, the form and composition of the raw material 8 can be adjusted in situ in step five to prepare functional gradient additive components with gradually changing microstructure and properties of each deposition layer during continuous deposition operations.

[0037] Exemplary Example 1 Combination Figure 1 , 34 and 5 describe this embodiment. The stirring friction deposition device based on heterogeneous mixed feed described in this embodiment is used to achieve in-situ alloying. The deposition device includes a tapered screw 1, a stationary shoulder 2, and a screw feeding device 3. Powder obtained by ball milling metal powder and alloy powder in a specific ratio is used as raw material 8 to achieve in-situ alloying in the screw extrusion plasticizing process. Subsequently, the plasticized metal 801 is discharged from the grinding space and forms a deposition layer under the combined action of the deposition device and the substrate 5. Component 4 is obtained by continuous deposition.

[0038] In this embodiment, the main shaft clamping part 101 of the main shaft clamping tapered screw 1 drives it to rotate. The metal powder and alloy powder are subjected to intense shearing, extrusion and friction by the screw compression section 103 of the tapered screw 1 in the grinding space, thereby plasticizing the powder and making it densely bonded. In this process, in-situ alloying is achieved. Subsequently, the continuously extruded plasticized metal 801 is transported to the screw metering section 104 and discharged from the grinding space as the tapered screw 1 rotates.

[0039] Exemplary Example 2 Combination Figure 1 , 3 4 and 5 describe this embodiment. The stirring friction deposition device based on heterogeneous mixed feeding described in this embodiment is used to realize in-situ composite material. The deposition device includes a tapered screw 1, a stationary shoulder 2, and a screw feeding device 3. Powder obtained by ball milling metal powder and reinforcing phase powder in a specific ratio is used as raw material 8 to realize the formation of metal matrix composite material during screw extrusion plasticization. Subsequently, the plasticized metal 801 is discharged from the grinding space and forms a deposition layer under the joint action of the deposition device and the substrate 5. Component 4 is obtained by continuous deposition.

[0040] In this embodiment, the main shaft clamping part 101 of the main shaft clamping tapered screw 1 drives its rotation. The metal and reinforcing phase ball milling powder are subjected to intense shearing, extrusion, and friction by the screw compression section 103 of the tapered screw 1 in the grinding space, thereby making the reinforcing phase uniformly distributed and densely bonded to the metal matrix. Subsequently, the continuously extruded plasticized metal 801 is transported to the screw metering section 104 and discharged from the grinding space as the tapered screw 1 rotates.

[0041] Exemplary Example 3 Combination Figure 2 , 3Sections 4, 5, 6, and 7 describe this embodiment. The stirring friction deposition apparatus based on heterogeneous mixed feed described in this embodiment is used to realize solid-phase additive manufacturing of heterogeneous structures. The deposition apparatus includes a tapered screw 1, a stationary shoulder 2, and a vibrating feeder 6. A raw material 8 with a specific ratio of metal particles with alloy powder / reinforcing phase powder attached to the surface is prepared using a binder. During the extrusion plasticizing process in the grinding space, the particles and powder are densely bonded to obtain a continuous plasticized metal 801 with a heterogeneous structure. Subsequently, the plasticized metal 801 is discharged from the grinding space and forms a deposition layer under the combined action of the deposition apparatus and the substrate 5. The component 4 is obtained by continuous deposition.

[0042] In this embodiment, the main shaft clamping part 101 of the main shaft clamping tapered screw 1 drives it to rotate. The raw material 8, which is formed by the bonding of metal particles and alloy powder / reinforcing phase particles, is subjected to severe shearing, extrusion and friction by the screw compression section 103 of the tapered screw 1 in the grinding space. Some areas (the areas where the powder is located) undergo severe plastic deformation and undergo dynamic recrystallization to form a high-strength fine-grained structure with a uniform distribution of reinforcing phase / alloying. Other areas still maintain a structure with larger grains and no reinforcing phase / alloying. Subsequently, the continuously extruded plasticized metal 801 is transported to the screw metering section 104 and discharged from the grinding space along with the rotation of the tapered screw 1. Under the combined action of the deposition device and the substrate 5, a deposition layer is formed. At this time, a heterogeneous structure with alternating distribution of coarse and fine grains and reinforcing phase / alloying can be formed in the deposition layer, so as to achieve the purpose of synergistic enhancement of the mechanical properties of heterogeneous components by multiple strengthening mechanisms.

[0043] In this embodiment, Figure 6 a is a morphology diagram of the raw material prepared by ball milling in this embodiment. Specifically, pure Al matrix particles and SiC reinforcing phase powder are ball-milled and mixed to obtain a composite material in which SiC powder is attached to the surface of pure Al particles; Figure 6 b is a microstructure diagram of the deposited layer obtained in this embodiment; the microstructure observation results show that the SiC reinforcing phase is uniformly dispersed in the pure Al matrix; the above results confirm that the method provided in Embodiment 3 of the present invention can successfully prepare a particle-reinforced aluminum matrix composite material with uniform microstructure and dispersed reinforcing phase.

[0044] In this embodiment, Figure 7 a is a morphology diagram of the raw material prepared by the oil adhesion process in this embodiment. Specifically, the surface of pure Zn matrix particles is first coated with an oil film, and then mixed with micron-sized pure Cu powder, thereby obtaining a composite raw material in which pure Cu powder is attached to the surface of pure Zn particles; Figure 7bd is a microstructure diagram of the deposited layer obtained in this embodiment; the microstructure observation results show that the Cu phase and the pure Zn matrix exhibit a regular alternating distribution inside the deposited layer; at the same time, the pure Zn matrix itself also exhibits a microstructure characteristic of alternating coarse-grained and fine-grained regions; the above results confirm that the method provided in Embodiment 3 of the present invention can successfully prepare heterogeneous structural materials with alternating distribution characteristics in both alloy composition and grain size.

[0045] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present technical solution are within the protection scope of the present invention.

Claims

1. A stirred friction deposition apparatus based on heterogeneous mixed feed, characterized in that, It includes a tapered screw (1), a stationary shoulder (2), and a feeding device (3); the tapered screw (1) is mounted on a rotating spindle, and the tapered screw (1) includes a spindle clamping part (101), a screw feeding section (102), a screw compression section (103), a screw metering section (104), and a thread (105); the stationary shoulder (2) includes a stationary shoulder clamping part (201), a feeding port (202), and a discharge port (203); the stationary shoulder... The shoulder (2) is installed on the stationary shoulder chuck so that the stationary shoulder (2) does not participate in the rotation. The tapered screw (1) is fitted inside the stationary shoulder (2). The bottom surfaces of the tapered screw (1) and the stationary shoulder (2) are on the same plane, and the gap between the tapered screw (1) and the stationary shoulder (2) forms the grinding space for the raw material (8). The feed port (202) cooperates with the feed device (3) to feed the raw material (8) into the grinding space.

2. The stirred friction deposition apparatus based on heterogeneous mixed feed according to claim 1, characterized in that, The raw material (8) includes metal particles, powder and metal particles with powder attached. The shape, size and ratio of the particles and the powder can be adjusted according to actual needs.

3. The stirred friction deposition apparatus based on heterogeneous mixed feed according to claim 1, characterized in that, The feeding device (3) is a screw feeding device. The screw feeding device feeds the raw material (8) into the grinding space formed by the tapered screw (1) and the stationary shoulder (2) through the feeding port (202). The discharge port (203) discharges the raw material after the action of the tapered screw (1) from the grinding space.

4. The stirred friction deposition apparatus based on heterogeneous mixed feed according to claim 1, characterized in that, The feeding device is a vibrating feeding device (6). The vibrating feeding device (6) feeds the raw material (8) through the feeding port (202) into the grinding space formed by the tapered screw (1) and the stationary shoulder (2) by vibrating and shaking the feeding pipe.

5. The stirred friction deposition apparatus based on heterogeneous mixed feed according to claim 1, characterized in that, The main shaft clamping part (101) is connected to the rotating main shaft. The screw feeding section (102), screw compression section (103) and screw metering section (104) all have the thread (105) and have the same outer diameter. The screw inner diameter of the screw feeding section (102) is the smallest and remains the same. The screw inner diameter of the screw compression section (103) gradually increases from top to bottom along the axial direction. The screw inner diameter of the screw metering section (104) is the largest and remains the same. The inner diameter of the screw feeding section (102) is the same as the inner diameter of the uppermost end of the screw compression section (103). The inner diameter of the screw metering section (104) is the same as the inner diameter of the lowermost end of the screw compression section (103). The ratio of the distance between the outer diameter and inner diameter of the screw feeding section (102) and the distance between the outer diameter and inner diameter of the screw metering section (104) is called the compression ratio of the tapered screw (1).

6. A method of using a stirred friction deposition apparatus based on heterogeneous mixed feed, implemented based on the stirred friction deposition apparatus based on heterogeneous mixed feed as described in any one of claims 1-5, characterized in that, Includes the following steps: Step 1: Determine the form and composition ratio of the raw material (8): Based on the structure and performance requirements of the target additive component, determine the form of the raw material, such as metal particles, powder or metal particles with attached powder, and clarify its composition and proportion, and put it into the storage funnel (7) for temporary storage. Step 2: Feed the raw material (8) into the grinding space: Select one of the feeding methods, either screw feeding device or vibrating feeding device (6), according to the applicability of the form of conveying the raw material (8), and feed the raw material (8) into the grinding space through the feeding port (202); Step 3, Tapered Screw (1) Extrusion of Plasticized Raw Material: The rotation of the main shaft drives the tapered screw (1) to rotate. The raw material is transported downward through the screw feeding section (102). When passing through the screw compression section (103), under the combined action of the inner wall of the stationary shoulder (2) and the screw compression section (103) of the tapered screw (1), the raw material (8) is subjected to severe shearing, extrusion and friction and enters a continuous thermoplastic state to obtain continuous plasticized metal (801). The continuous plasticized metal (801) is discharged from the grinding space through the discharge port (203) through the screw metering section (104). Step 4, Deposition layer formation: After the continuously extruded plasticized metal (801) is discharged from the grinding space, a deposition layer is formed under the joint constraint of the substrate (5) and the bottom surface of the deposition device; Step 5, continuous deposition operation: With the help of the feeding device (3), continuous feeding can realize continuous deposition operation according to the preset trajectory, and additive manufacturing of specified components (4).

7. The method of using the stirred friction deposition apparatus based on heterogeneous mixed feed according to claim 6, characterized in that, The raw material (8) is composed of physical morphological characteristics and chemical composition characteristics, wherein the physical morphological characteristics are selected from at least one of particles, powders and composite particles with powder attached to the surface; the chemical composition characteristics are selected from at least one of pure metals, alloys, reinforcing phases and metal matrix composites; the specific form of the raw material (8) is any combination of any of the above physical morphological characteristics and any of the chemical composition characteristics. The reinforcing phase includes, but is not limited to, carbides, oxides, nitrides, carbon group materials, and intermetallic compounds.

8. The method of using the stirred friction deposition apparatus based on heterogeneous mixed feed according to claim 7, characterized in that, The metal particles in step one are pure metal particles or alloy particles; The shape and size of the particles can be flexibly adjusted according to the requirements of the feeding device, deposition device and component structure and performance. The composition of the metal particles can be particles with one component or a mixture of two or more particle components. The powder in step one is one or more of pure metal powder, alloy / metal matrix composite powder, and mixed powder of metal / alloy and reinforcing phase. The shape and size of the powder can be flexibly adjusted according to the requirements of the feeding device (3), the deposition device and the microstructure and properties of the component. The metal particles with powder attached to their surface in step one include, but are not limited to, pure metal particles with attached alloy powder, alloy particles with attached alloy powder, pure metal particles with attached reinforcing phase powder, and alloy particles with attached reinforcing phase powder.

9. The method of using the stirred friction deposition apparatus based on heterogeneous mixed feed according to claim 6, characterized in that, In step three, the compression ratio and size of the tapered screw (1) can be adjusted according to the mixing characteristics of the raw material (8), the ease of plasticization, and the target microstructure.

10. The method of using the stirred friction deposition apparatus based on heterogeneous mixed feed according to claim 6, characterized in that, In step five, the form and composition of the raw material (8) can be adjusted in situ to prepare functional gradient additive components with gradually changing properties of each deposition layer during continuous deposition operations.

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