A wallboard high rib processing technology using friction stir additive forming

Abstract

This invention provides a high-ribbed wall panel manufacturing process using friction stir additive manufacturing, comprising: forming a high-ribbed blank on a wall panel using a friction stir solid-state additive manufacturing device; milling the high-ribbed blank using a milling machine to obtain ribs composed of stacked trapezoidal steps; calculating the compression deformation of each trapezoidal step based on the structural dimensions of the ribs, and pre-extruded each trapezoidal step according to the obtained compression deformation; performing a secondary milling on the extruded ribs using a milling machine to achieve the target specifications; and performing creep aging forming on the wall panel after the secondary milling in an autoclave. This invention uses friction stir additive manufacturing to form a high-ribbed blank, solving the problems of material waste and high manufacturing costs in existing subtractive manufacturing processes. Simultaneously, by compressing and deforming the additively formed ribs, the strength of the additive bonding surface can be improved, thus enhancing the performance of the additive blank.

Description

Technical Field

[0001] This invention relates to the field of aerospace large high-rib panel forming technology, specifically to a high-rib panel processing technology using friction stir additive manufacturing. Background Technology

[0002] With the rapid development of high-end equipment in the aerospace field, there is an urgent need to manufacture large, complex wall panel components that are high-performance, lightweight, and high-precision. Currently, large wall panel processing typically employs subtractive manufacturing processes, which result in significant material waste and high manufacturing costs for large, highly ribbed wall panels. Additive manufacturing, a forming method that uses layered accumulation of raw materials, offers advantages such as short manufacturing cycles and high material utilization, making it of significant research value for the forming of large, highly ribbed wall panels. Friction stir additive manufacturing (FSM) is a solid-phase additive manufacturing process that achieves metal deposition additive manufacturing through friction stirring, extrusion, plastic deformation, and layered stacking principles. During FSM, the metal material does not undergo melting or solidification, overcoming the metallurgical defects such as porosity, incomplete fusion, and hot cracks that are difficult to completely eliminate in fusion welding additive manufacturing processes. However, the bonding strength at the interlayer interface is relatively low. Research indicates that compressive deformation can improve the interface strength, resulting in better mechanical properties for the highly ribbed additive manufacturing process.

[0003] Compression pre-deformation, as a core means of controlling the microstructure and mechanical properties of aluminum alloys, has received widespread attention in the field of materials science and engineering in recent years. This technology significantly alters the dislocation density, precipitate distribution, and residual stress state of aluminum alloys by applying a certain amount of plastic deformation, thereby achieving synergistic optimization of properties such as strength, toughness, and fatigue life. Current compression pre-deformation methods typically employ rolling deformation, roll forming deformation, and stamping deformation. The corresponding compression deformation dies are mostly simple planar structures, making it difficult to achieve uniform deformation of structural components. Because grid-ribbed panels have intersecting longitudinal and transverse ribs, rolling deformation and roll forming deformation easily lead to rib instability, making it difficult to achieve the purpose of rib compression deformation. Existing compression dies for stamping deformation are difficult to effectively deform the ribbed panels. Stamping deformation generally places the component to be compressed completely inside the die, resulting in a large and complex overall die structure with low practicality. It is typically used for small parts and cannot be used for large, highly ribbed panels.

[0004] In summary, there is an urgent need for a high-ribbed wall panel processing technology using friction stir additive manufacturing to solve the problems existing in the prior art. Summary of the Invention

[0005] The purpose of this invention is to provide a high-ribbed wall panel processing technology using friction stir additive manufacturing, aiming to solve the problems of serious material waste and high manufacturing costs in the subtractive manufacturing process used in the processing of large wall panels in the prior art, and the inapplicability of existing pre-deformation methods such as rolling, roll forming, and stamping to wall panels with grid ribs. The specific technical solution is as follows: A high-ribbed wall panel manufacturing process using friction stir additive manufacturing includes: High-gluten billet is formed by friction stir additive manufacturing: a high-gluten billet is formed on the wall panel by solid-phase additive manufacturing using friction stir solid-phase additive manufacturing equipment; High-gluten billet side milling: The high-gluten billet is milled using a milling machine to obtain a material with the following characteristics: A rib is formed by stacking trapezoidal steps; wherein the cross-section of each trapezoidal step perpendicular to its length is an isosceles trapezoid, and between two adjacent trapezoidal steps, the lower base of the isosceles trapezoid corresponding to the upper trapezoidal step is shorter than the upper base of the isosceles trapezoid corresponding to the lower trapezoidal step. It is a natural number greater than or equal to 2; Rib pre-compression deformation: Calculate the compression deformation of each trapezoidal step based on the structural dimensions of the rib, and perform pre-compression deformation on each trapezoidal step according to the obtained compression deformation. Secondary milling of ribs: The extruded ribs are milled a second time using a milling machine to bring the ribs to the target size specifications. Creep aging treatment: The wall panel after secondary milling is subjected to creep aging forming in an autoclave.

[0006] Preferably, the pre-extrusion deformation of the reinforcing ribs specifically involves: S1. Obtain the parameters of each trapezoidal step based on the structural dimensions of the ribs. and And calculate the coefficient of each trapezoidal step. ; in, Indicates the first The initial length of the median of the isosceles trapezoid corresponding to each trapezoidal step. Indicates the first The initial cross-sectional area of ​​each trapezoidal step along the vertical centerline of the reinforcing rib is given by the following numbers from top to bottom: , ; S2. Set the compression deformation increment of the rib. and initial compressive deformation At the same time, ; S3. Calculate the compressive deformation of the reinforcing bar. The amount of compression deformation of each trapezoidal step Based on the compression deformation of each trapezoidal step Perform extrusion simulation on the reinforcing bars and output the simulation results; in, , Indicates the first Trapezoidal steps in the second simulation The amount of compressive deformation; S4. Determine if the termination condition is met. If not, let... , Then return to S3, and if the condition is met, proceed from... The group with the optimal compression deformation was selected from the simulation results. , ; S5. According to the optimal compression deformation group This completes the compression of the ribs.

[0007] Preferably, the coefficient of the trapezoidal step Represented as: in, and All are coefficients.

[0008] Preferred coefficient and The calculation method is as follows: For trapezoidal steps and Extrusion simulation was performed, in which trapezoidal steps were used. and The compression deformation in the extrusion simulation is all , Satisfying the trapezoidal steps and No damage occurred. and ; Measurement of trapezoidal steps Compression deformation and trapezoidal steps Compression deformation ; in, , , Trapezoidal steps The initial length of the median of the corresponding isosceles trapezoid. Trapezoidal steps after compression The length of the median of the corresponding isosceles trapezoid. Trapezoidal steps The initial length of the median of the corresponding isosceles trapezoid. Trapezoidal steps after compression The length of the median of the corresponding isosceles trapezoid; Calculate trapezoidal steps coefficient and trapezoidal steps coefficient ;in, , ; Construct the system of equations as follows Calculate the coefficients and The value; in, Trapezoidal steps before compression The initial cross-sectional area along the vertical centerline of the reinforcing bar. Trapezoidal steps before compression The initial cross-sectional area along the vertical centerline of the reinforcing bar.

[0009] Preferably, step S4 specifically involves: if Then let , Then return to S3, otherwise start from... The group with the optimal compression deformation was selected from the simulation results. , , This represents the maximum compressibility deformation of the stiffener.

[0010] Preferably, the maximum compressibility deformation of the rib. Represented as: in, The initial length of the median of the isosceles trapezoid corresponding to the uppermost trapezoidal step. Let be the initial length of the median of the isosceles trapezoid corresponding to the lowest trapezoidal step. This is the coefficient of the lowest trapezoidal step.

[0011] Preferably, step S4 specifically involves: determining whether the rib has been damaged based on the current simulation results; if the rib has not been damaged, then... , Then return to S3; if damage occurs, then from... The group with the optimal compression deformation was selected from the simulation results. , .

[0012] Preferably, step S5 specifically involves: simultaneously applying compressive force along the normal direction to both sides of each trapezoidal step to complete the compression of the ribs; wherein, the amount of compression deformation of the sides of each trapezoidal step from top to bottom is sequentially controlled as follows: The side refers to the plane containing the waist of the isosceles trapezoid corresponding to the trapezoidal step.

[0013] Preferred, from When selecting the optimal compression deformation group from the simulation results, the optimal compression deformation group is the one where the ribs deform uniformly as a whole and there is no stress concentration or rib failure.

[0014] Preferably, the stirring head of the friction stir solid additive manufacturing equipment rotates at a speed of 300-400 r / min and advances at a speed of 135-155 mm / min; The pressure inside the autoclave is 1-2 MPa, the temperature is 160-180℃, and the heat and pressure holding time is 16-18 hours.

[0015] The application of the technical solution of the present invention has the following beneficial effects: The processing technology of this invention solves the problem of forming high-ribbed wall panels. By controlling the pre-deformation of the rib components individually, it overcomes the problem that existing pre-deformation methods such as rolling, pressing, and stamping are not suitable for wall panels with mesh ribs, thus improving the mechanical properties of the ribbed wall panels. At the same time, this invention uses friction stirring additive manufacturing to form high-ribbed blanks, which solves the problems of material waste and high manufacturing costs in existing subtractive manufacturing processes. By compressing and deforming the additively formed ribs, the strength of the additive bonding surface can be improved, thus improving the performance of the additive blank.

[0016] This invention enables pre-deformation control of rib components, improving the mechanical properties of rib panels and the strength of additive bonding surfaces. By calculating the compression deformation of each trapezoidal step, the extrusion components in the extrusion die are guided to adjust the extrusion stroke, making the deformation of the ribs at different positions more uniform during the compression deformation process and effectively avoiding stress concentration.

[0017] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the rib structure in this invention; Figure 2 This is a schematic diagram of the working state of the extrusion die in Example 1; Figure 3 This is a schematic diagram of the extrusion die in Example 1; Figure 4 yes Figure 3 A schematic diagram of the structure of the extrusion module; Figure 5 yes Figure 4 Schematic diagram of the middle and lower pressing components; Figure 6 yes Figure 3 Assembly diagram of the sliding bearing, push rod and front end plate; Figure 7 yes Figure 3 A schematic diagram of the locking module; Figure 8 This is a flowchart of the extrusion method in Example 2; Figure 9 shows the example in Example 2. Figure 9(a) shows the simulation results of the compression under pressure. Figure 9(b) shows the simulation results of the cross-sectional strain perpendicular to the length of the stiffener. Figure 9(c) shows the simulation results of the cross-sectional stress perpendicular to the length of the stiffener. Figure 9(d) shows the simulation results of the stress at point AA in Figure 9(c). Figure 10 shows the example in Example 2. Figure 10(a) shows the simulation results of the compression under pressure. Figure 10(b) shows the simulation results of the cross-sectional strain perpendicular to the length of the stiffener. Figure 10(c) shows the simulation results of the cross-sectional stress perpendicular to the length of the stiffener. Figure 10(d) shows the simulation results of the stress at point AA in Figure 10(c). Figure 11 shows the example in Example 2. Figure 11(a) is a schematic diagram of the cross-sectional strain simulation results perpendicular to the length direction of the stiffener, Figure 11(b) is a schematic diagram of the strain simulation results at point AA in Figure 11(a), Figure 11(c) is a schematic diagram of the cross-sectional stress simulation results perpendicular to the length direction of the stiffener, and Figure 11(d) is a schematic diagram of the stress simulation results at point AA in Figure 11(c). Figure 12 This is a flowchart of the processing technology in Example 3; Among them, 1. wall panel, 2. rib, 2.1. trapezoidal step, 3. locking module, 3.1. outer frame, 3.2. push plate, 3.3. adjusting bolt, 3.4. locking bolt assembly, 3.5. adjusting groove, 3.6. clearance opening, 4. extrusion module, 4.1. pressure rod, 4.2. extrusion column, 4.3. side plate, 4.4. guide slide, 4.5. adjusting cap, 4.6. push rod, 4.7. pressure plate, 4.8. spherical sliding bearing, 4.9. front end plate, 4.10. rear end plate, 4.11. slide rod. Detailed Implementation

[0019] To facilitate understanding of the present invention, a more complete description is provided below, along with preferred embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0020] 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 invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0021] Example 1: See Figures 2-7 This embodiment provides an extrusion die for a high-ribbed wall panel in friction stir additive manufacturing, wherein the ribs 2 on the wall panel 1 include stacked ribs. Each trapezoidal step 2.1 has an isosceles trapezoidal cross-section perpendicular to the length of the reinforcing rib. Between two adjacent trapezoidal steps 2.1, the lower base length of the isosceles trapezoid corresponding to the upper trapezoidal step 2.1 is less than the upper base length of the isosceles trapezoid corresponding to the lower trapezoidal step 2.1. That is, the length of each trapezoidal step 2.1 gradually increases from top to bottom. It is a natural number greater than or equal to 2; like Figure 1 As shown, between adjacent trapezoidal steps 2.1, there is no clear boundary between the lower base of the upper trapezoidal step 2.1 and the upper base of the lower trapezoidal step 2.1; they are stacked together. Each trapezoidal step 2.1 is an integral structure; furthermore, each trapezoidal step 2.1 is symmetrically arranged according to the vertical center line of the rib 2, that is, the midpoint of the upper base and the midpoint of the lower base of each isosceles trapezoid are located on the vertical center line of the rib 2. In this way, the compressive force can be applied symmetrically on both sides of the rib 2 (that is, the compressive force is applied symmetrically to each trapezoidal step 2.1), ensuring that the deformation at different positions of the rib is uniform and avoiding stress concentration.

[0022] like Figures 3-7 As shown, the extrusion die includes a locking module 3 and an extrusion module 4. The two extrusion modules 4 are symmetrically arranged on both sides of the rib 2. The locking module 3 is used to constrain the relative position between the two extrusion modules 4. The two extrusion modules 4 are used to apply normal extrusion force to the sides of each trapezoidal step 2.1 from both sides of the rib 2. Specifically, the extrusion module 4 includes a pressing component, a frame, and extrusion members. The frame has vertically spaced components on the side facing the rib 2. A set of extrusion components is provided, with each extrusion component corresponding to one of the trapezoidal steps 2.1. That is, a set of extrusion components applies extrusion force to one side of a trapezoidal step 2.1. A lower pressing member is vertically slidable on the frame and located behind the extrusion components. During the downward pressing process, the lower pressing member sequentially pushes each extrusion component outward, thereby applying an extrusion force perpendicular to the side of each trapezoidal step 2.1. Further, in this embodiment, the side of the trapezoidal step 2.1 refers to the plane containing the two sides of the isosceles trapezoid corresponding to the trapezoidal step 2.1.

[0023] like Figure 3 and Figure 4 As shown, the extrusion component includes an adjusting cap 4.5, a pressure plate 4.7, and at least one push rod 4.6. The push rod 4.6 is slidably mounted on the frame. The end of the push rod 4.6 near the lower pressing member is provided with an adjusting cap 4.5, and the end near the rib 2 is provided with a pressure plate 4.7. The axis of the push rod 4.6 is perpendicular to the plane where the pressure plate 4.7 is located, and the pressure plate 4.7 is parallel to the side of the corresponding trapezoidal step 2.1.

[0024] Preferably, the extrusion component in this embodiment includes two push rods 4.6, which are arranged in parallel and slidably mounted on the frame. The ends of the two push rods 4.6 are simultaneously connected to the pressure plate 4.7. Of course, in some embodiments, more push rods 4.6 may be arranged in parallel. By setting multiple push rods 4.6, it can be ensured that the extrusion force exerted by the pressure plate 4.7 on the side of the trapezoidal step 2.1 is consistent, thus achieving uniform extrusion.

[0025] like Figure 5 As shown, the pressing component includes a pressure rod 4.1 and an extrusion column 4.2 disposed at the lower end of the pressure rod 4.1. The extrusion column 4.2 is disposed inside the frame and located behind the adjusting cap 4.5. Both ends of the extrusion column 4.2 are provided with sliding rods 4.11. The extrusion column 4.2 is slidably disposed in the guide groove 4.4 on the frame through the sliding rods 4.11 on both sides.

[0026] Specifically, during the pressing process of the pressing member, the downward-moving extrusion column 4.2 will squeeze the adjusting cap 4.5 from the rear end of the adjusting cap 4.5, thereby pushing the push rod 4.6 and the pressure plate 4.7 towards the side closer to the rib 2, thus achieving the effect of applying extrusion force to the side of the trapezoidal step 2.1.

[0027] Preferably, the size of the pressure plate 4.7 should be matched with the side of the trapezoidal step 2.1 to ensure that the pressure plate 4.7 can completely cover the side of the trapezoidal step 2.1 in the length direction of the waist.

[0028] Preferably, the end of the adjusting cap 4.5 near the extrusion column 4.2 is spherical, and the extrusion column 4.2 is cylindrical. This allows the adjusting cap 4.5 and the extrusion column 4.2 to form point contact, reducing the contact resistance between them and facilitating the extrusion column 4.2 to accurately push the adjusting cap 4.5, push rod 4.6 and pressure plate 4.7 to move together.

[0029] Preferably, the adjusting cap 4.5 and the push rod 4.6 are threaded together, and the extrusion stroke of the extrusion component can be adjusted by turning the adjusting cap 4.5. Specifically, before extruding the rib 2, the pressure plate 4.7 needs to be pressed tightly against the side of the corresponding trapezoidal step 2.1. During the process of adjusting the extrusion stroke by turning the adjusting cap 4.5, the closer the adjusting cap 4.5 is to the extrusion column 4.2, the greater the extrusion stroke of the extrusion component; the farther the adjusting cap 4.5 is from the extrusion column 4.2, the smaller the extrusion stroke of the extrusion component.

[0030] Of course, when the extrusion stroke requirement cannot be met by simply turning the adjusting cap 4.5, it can also be met by replacing the adjusting cap 4.5 with one of different thicknesses. It should be noted that in some embodiments, the extrusion stroke may not be adjusted by threaded connection between the adjusting cap 4.5 and the push rod 4.6; it is also feasible to adjust the extrusion stroke simply by replacing the adjusting cap 4.5 with one of different thicknesses.

[0031] like Figure 6 As shown, the push rod 4.6 is mounted on the frame via a spherical sliding bearing 4.8. The spherical sliding bearing 4.8 allows for adjustment of the tilt angle of the push rod 4.6, i.e., adjustment of the direction of the extrusion force, thereby adapting to different inclination angles and improving the adaptability of the extrusion die. It should be noted that before formally extruding the rib 2, the pressure plate 4.7 needs to be tightly attached to the side of the trapezoidal step 2.1. Since there is a step between the sides of the upper and lower trapezoidal steps 2.1, it can limit the pressure plate 4.7. Therefore, the degree of freedom provided by the spherical sliding bearing 4.8 does not affect the direction of the extrusion force applied by the push rod 4.6.

[0032] It should be noted that in some embodiments, the push rod 4.6 may not be mounted on the frame via the spherical sliding bearing 4.8. For example, it is also feasible to mount it on the frame via a linear bearing. In this configuration, the push rod 4.6 can only apply normal compressive force in a specific direction. Therefore, this configuration is only applicable when the inclination angle of the side of the trapezoidal step 2.1 is known. In this configuration, the axial direction of the linear bearing should be perpendicular to the side of the corresponding trapezoidal step.

[0033] Furthermore, the push rod 4.6 and the pressure plate 4.7 can be integrated into one piece, and the push rod 4.6 and the spherical sliding bearing 4.8 or linear bearing are detachably connected, which makes it convenient to replace the pressure plate 4.7 of different sizes according to the size of the side of the trapezoidal step.

[0034] like Figure 3 and Figure 4 As shown, the frame includes a side plate 4.3, a front plate 4.9, and a rear plate 4.10. The front plate 4.9 and the rear plate 4.10 are arranged opposite to each other and are connected on both sides by the side plate 4.3. The side plate 4.3 is provided with a guide groove 4.4. The slide rods 4.11 at both ends of the extrusion column 4.2 are respectively arranged in the guide grooves 4.4 of the two side plates 4.3. The push rod 4.6 is slidably arranged on the front plate 4.9.

[0035] Specifically, the guide groove 4.4 on the frame can guide the downward pressing movement of the extrusion column 4.2 on the one hand, and constrain the extrusion column 4.2 on the other hand. The constrained extrusion column 4.2 will not move unnecessarily during the extrusion adjustment cap 4.5, so as to achieve precise control of the extrusion stroke of the extrusion component (i.e., precise control of the deformation of the trapezoidal step 2.1).

[0036] like Figure 3 and Figure 7 As shown, the locking module 3 includes an outer frame 3.1, a push plate 3.2, and an adjusting bolt 3.3. The push plate 3.2 is slidably disposed at the first end of the outer frame 3.1, and a space is formed between the push plate 3.2 and the second end of the outer frame 3.1 to accommodate two symmetrically arranged compression modules 4. The adjusting bolt 3.3 is disposed at the first end of the outer frame 3.1 and abuts against the push plate 3.2.

[0037] Specifically, the outer frame 3.1 includes a connecting plate and two end plates. The two end plates are respectively located at the first and second ends of the connecting plate. The push plate 3.2 and the end plate at the second end form a space to accommodate two extrusion modules. Tightening the adjusting bolt 3.3 can adjust the position of the push plate 3.2, thereby adjusting the distance between the two extrusion modules and constraining the distance between the two extrusion modules to remain unchanged during the extrusion process. Specifically, during the extrusion of the rib 2, the frames of the two extrusion modules respectively abut against the push plate 3.2 and the end plate at the second end, achieving the effect of constraining the distance between the two extrusion modules.

[0038] Furthermore, the connecting plate is located above the two extrusion modules, and the connecting plate is provided with a clearance opening 3.6. The clearance opening 3.6 allows the pressure rod 4.1 to pass through, and at the same time, the clearance opening 3.6 can meet the need for flexible adjustment of the distance between the two extrusion modules. Preferably, in some embodiments, the connecting plate may be provided on the side of the two extrusion modules, in which case the clearance opening 3.6 is not required.

[0039] Preferably, the locking module 3 further includes a locking bolt assembly 3.4. The first end of the outer frame 3.1 (i.e. the first end of the connecting plate) is provided with an adjustment groove 3.5. The push plate 3.2 is provided with a round hole. The bolt in the locking bolt assembly 3.4 passes through the round hole and the adjustment groove 3.5 and is tightened with a nut. In this way, the push plate 3.2 can slide relative to the outer frame 3.1, and can also be locked by the locking bolt assembly 3.4.

[0040] In this embodiment, the extrusion force applied by the extrusion die is perpendicular to the side of the trapezoidal step, so that while applying lateral pressure to the rib, it can also apply vertical pressure. The extrusion forces in the two directions work together on the rib, resulting in a better extrusion effect and improved rib performance.

[0041] In this embodiment, a single extrusion module includes modules spaced vertically apart. The compression members, the compression on one side of the reinforcing rib is caused by... The extrusion components are completed sequentially. On the one hand, this reduces the pressure requirements of the extrusion module. Each extrusion component performs the extrusion task in turn, and the pressure of the pressing component is applied to only one extrusion component at a time. Compared with extruding the entire side of the rib at once, this greatly reduces the requirements for the pressure and pressurizing equipment. On the other hand, the deformation of each trapezoidal step can be controlled by the corresponding extrusion component, making the deformation of the rib at different positions more uniform during the compression deformation process and effectively avoiding stress concentration.

[0042] In this embodiment, the push rod is mounted on the frame via a spherical sliding bearing. The push rod has an adjustment cap at one end near the lower pressure member. The adjustment cap and the spherical sliding bearing work together to quickly adapt to different specifications of ribs, thus providing high adaptability to different specifications of ribs.

[0043] The extrusion die in this embodiment can meet the compression deformation requirements of the rib structure, realize pre-deformation control of the rib component, and improve the mechanical properties of the rib panel; at the same time, the compression deformation of the additively formed rib can improve the strength of the additive bonding surface and improve the performance of the additive blank.

[0044] Example 2: This embodiment provides an extrusion method for producing a high-ribbed wall panel using friction stir additive manufacturing. The extrusion method in this embodiment employs the extrusion die from Embodiment 1. Specifically, after initially forming a high-ribbed blank on the wall panel 1 using friction stir additive manufacturing, the high-ribbed blank needs to be milled to obtain the desired shape. Figure 1 The diagram shows the composition of the diagram. The rib shape is formed by stacking trapezoidal steps 2.1, and then the rib 2 is extruded and pre-deformed using the extrusion mold in Example 1.

[0045] To facilitate understanding of how the compressive deformation of each trapezoidal step 2.1 is calculated in this embodiment, the following introduction will be provided first: Common sense tells us that the formula for plastic deformation of a regularly shaped object (such as a cylinder) under compression is: in, For objects with regular shapes, the amount of deformation. The initial length of the regularly shaped object. Let be the initial cross-sectional area of ​​the regularly shaped object. It is the cross-sectional area of ​​the object after compression deformation (specifically, the cross-section at the location of the maximum deformation after compression).

[0046] Furthermore, to ensure that the deformation of the ribs is consistent at various heights during compression deformation, this embodiment introduces a coefficient. Corrected trapezoidal steps The formula for plastic deformation is: The trapezoidal steps 2.1, from top to bottom, are numbered sequentially as follows: , , Trapezoidal steps The corresponding coefficients, Trapezoidal steps The amount of deformation, Trapezoidal steps The initial length of the median of the corresponding isosceles trapezoid. Trapezoidal steps The initial cross-sectional area along the vertical centerline of the reinforcing bar. Trapezoidal steps The cross-sectional area along the vertical centerline of the rib after deformation, such as... Figure 1 As shown, Figure 1 The AA section is located at the position of the vertical centerline of the reinforcing bar.

[0047] Furthermore, due to the trapezoidal steps Deformation amount as well as and The changes between them all stem from the basic relationship that deformation = original length × strain, therefore the trapezoidal step The formula for plastic deformation can be expressed as: in, Represents trapezoidal steps The amount of compression deformation, , Trapezoidal steps after compression The length of the median of the corresponding isosceles trapezoid.

[0048] Preferred, trapezoidal steps Corresponding coefficients Represented as: in, and All are coefficients.

[0049] Furthermore, the coefficient and The calculation method is as follows: For trapezoidal steps and Extrusion simulation was performed, in which trapezoidal steps were used. and The compression deformation in the extrusion simulation is all , Satisfying the trapezoidal steps and No damage occurred. and In this embodiment, we take =3%; Measurement of trapezoidal steps Compression deformation and trapezoidal steps Compression deformation ; in, , , Trapezoidal steps The initial length of the median of the corresponding isosceles trapezoid. Trapezoidal steps after compression The length of the median of the corresponding isosceles trapezoid. Trapezoidal steps The initial length of the median of the corresponding isosceles trapezoid. Trapezoidal steps after compression The length of the median of the corresponding isosceles trapezoid; Calculate trapezoidal steps coefficient and trapezoidal steps coefficient ;in, , ; Construct the system of equations as follows Calculate the coefficients and The value of; where, Trapezoidal steps before compression The initial cross-sectional area along the vertical centerline of the reinforcing bar. Trapezoidal steps before compression The initial cross-sectional area along the vertical centerline of the reinforcing bar.

[0050] Furthermore, such as Figure 8 As shown, the specific method for extruding the ribs using the above-mentioned extrusion die is as follows: S1. Obtain the parameters of each trapezoidal step 2.1 based on the structural dimensions of rib 2. and And calculate the coefficient of each trapezoidal step 2.1. ;in, Indicates the first The initial length of the median of the isosceles trapezoid corresponding to each trapezoidal step 2.1. Indicates the first 2.1 Initial cross-sectional area of ​​the trapezoidal step along the vertical centerline of the reinforcing bar; Specifically, such as Figure 1 As shown, the initial lengths of the medians of the isosceles trapezoids corresponding to each trapezoidal step from top to bottom are denoted as follows: The initial cross-sectional area of ​​each trapezoidal step along the vertical centerline of the reinforcing rib is denoted as follows: ; in coefficient and Given the information, substitute it into the formula. The coefficients corresponding to each trapezoidal step can then be calculated. .

[0051] S2. Set the compression deformation increment of the rib. and initial compressive deformation At the same time, ; S3. Calculate the compressive deformation of the reinforcing bar. The compressive deformation of each trapezoidal step 2.1 Based on the compressive deformation of each trapezoidal step 2.1 Perform extrusion simulation on the reinforcing bars and output the simulation results; among them, , Indicates the first Trapezoidal steps in the second simulation The amount of compressive deformation; Specifically, trapezoidal steps are set during the extrusion simulation process. The amount of compressive deformation is The current compression deformation set is obtained through simulation. Simulation results of the lower reinforcing bar.

[0052] S4. Determine if the termination condition is met. If not, let... , Then return to S3, and if the condition is met, proceed from... The group with the optimal compression deformation was selected from the simulation results. , ; Preferably, step S4 specifically involves: if Then let , Then return to S3, otherwise start from... The group with the optimal compression deformation was selected from the simulation results. , , This represents the maximum compressibility deformation of the stiffener.

[0053] Furthermore, the maximum compressibility deformation of the rib. Represented as: in, The initial length of the median of the isosceles trapezoid corresponding to the uppermost trapezoidal step. Let be the initial length of the median of the isosceles trapezoid corresponding to the lowest trapezoidal step. The coefficient is 2.1 for the lowest trapezoidal step.

[0054] In addition, step S4 can also be: determining whether the rib has been damaged based on the current simulation results; if the rib has not been damaged, then... , Then return to S3; if damage occurs, then from... The group with the optimal compression deformation was selected from the simulation results. , .

[0055] Preferably, those skilled in the art can set the compression deformation increment as appropriate. When the compression deformation increment The smaller the value of , the more experiments are needed for the compression simulation, and the better the optimal set of compression deformation values ​​can be obtained. The closer to the true optimal set of compressive deformation values; the more the compressive deformation increment... The larger the value of , the fewer experiments are needed for the compression simulation, but the optimal set of compression deformation values ​​is obtained. The deviation from the actual optimal set of compressive deformation is also relatively large.

[0056] Specifically, from When selecting the optimal compression deformation set from the simulation results, the set that exhibits uniform overall deformation of the ribs and exhibits no stress concentration or rib failure is generally chosen as the optimal set. However, those skilled in the art can flexibly adjust the selection criteria for the optimal compression deformation set based on actual simulation results and pre-compression targets.

[0057] S5. According to the optimal compression deformation group Adjust the extrusion stroke of each extrusion component in extrusion module 4 to complete the extrusion of rib 2.

[0058] Specifically, after the pressure plates 4.7 of each extrusion component are tightly attached to the side of the corresponding trapezoidal step 2.1, the extrusion stroke of each extrusion component is adjusted to the corresponding position using the adjusting caps 4.5. Then, by controlling the pressurizing equipment to drive the pressing component to press down, the pre-extrusion of the ribs can be completed, so that the ribs can obtain the optimal pre-extrusion effect.

[0059] The extrusion method of this embodiment can achieve pre-deformation control of the rib members, improve the mechanical properties of the rib wall panel and the strength of the additive bonding surface. By calculating the compression deformation of each trapezoidal step, the extrusion components in the extrusion die are guided to adjust the extrusion stroke, so that the deformation of the rib at different positions during the compression deformation process is more uniform, effectively avoiding stress concentration.

[0060] Furthermore, this embodiment also provides implementation examples of the above extrusion method, as detailed below: In this case, there are a total of 5 trapezoidal steps, each with a height of 8mm and a rib length of 10mm. Therefore, the initial cross-sectional area of ​​each trapezoidal step along the vertical centerline of the rib is 80. The initial lengths of the median of the isosceles trapezoids corresponding to each trapezoidal step were measured to be 7mm, 11mm, 15mm, 19mm and 23mm respectively.

[0061] By applying a 3% compression deformation to both the first and second trapezoidal steps, the following calculations were performed. , -0.12, coefficient of each trapezoidal step The coefficients of each trapezoidal step are obtained. As shown in Table 1: Table 1. Coefficients of each trapezoidal step Statistical table In this case, the compression deformation increment is set. Initial compressive deformation The termination condition is whether the reinforcing bars are damaged.

[0062] First, the calculation is obtained The compression deformation set in the extrusion simulation is {0.2mm, 0.6mm, 1.1mm, 1.8mm, 2.7mm}. The simulation results at this time are shown in Figures 9(a)-9(d). According to Figures 9(a)-9(d), the overall deformation of the rib under the current compression deformation set is too small, the undeformed area is large, the work hardening effect is weakened, and there is no stress concentration phenomenon.

[0063] Furthermore, calculations yielded... The compression deformation set during the extrusion simulation is {0.5mm, 1.2mm, 2.3mm, 3.6mm, 5.4mm}. The simulation results at this time are shown in Figures 10(a)-10(d). According to Figures 10(a)-10(d), the overall deformation of the rib under the current compression deformation set is uniform, and the deformation is between 20% and 40%, and there is no stress concentration phenomenon.

[0064] Furthermore, calculations yielded... The compression deformation set during the extrusion simulation is {0.7mm, 1.8mm, 3.4mm, 5.5mm, 8.1mm}. The simulation results at this time are shown in Figures 11(a)-11(d). According to Figures 11(a)-11(d), there is no stress concentration phenomenon in the ribs, but the overall deformation of the ribs is too large, and the top ribs are damaged.

[0065] Because when The ribs failed, therefore the extrusion simulation experiment was terminated. The simulation results shown in Figures 9-11 indicate that... Although the deformation is uniform, the amount of deformation is low, and there are undeformed areas in the middle. At the point where the deformation is at its maximum and the ribs are damaged, the pre-extrusion requirements cannot be met, increasing the difficulty of subsequent milling; and The deformation amount is moderate, which not only meets the deformation requirements of the rib but also does not interfere with the subsequent rib milling, thus fully meeting the process requirements. Therefore, {0.5mm, 1.2mm, 2.3mm, 3.6mm, 5.4mm} is selected as the optimal compression deformation amount group. Subsequently, when the rib is extruded using an extrusion die, the extrusion stroke of each extrusion component is set to 0.5mm, 1.2mm, 2.3mm, 3.6mm and 5.4mm from top to bottom.

[0066] Example 3: See Figure 12This embodiment also provides a high-ribbed wall panel processing technology using friction stir additive manufacturing, which aims to solve the problem that the compression pre-deformation method in the prior art cannot be applied to wall panels with mesh ribs. By performing compression pre-deformation on the high ribs of the wall panel, the performance of the wall panel is improved. The processing technology includes the following steps: High-gluten billet is formed by friction stir additive manufacturing: a high-gluten billet is formed on a flat wall panel 1 by solid-phase additive manufacturing using a friction stir solid-phase additive manufacturing equipment; wherein, in this embodiment, the stirring head of the friction stir solid-phase additive manufacturing equipment rotates at a speed of 300-400 r / min and has a forward speed of 135-155 mm / min; High-gluten billet side milling: The high-gluten billet is milled using a milling machine to obtain a material with the following characteristics: A rib shape formed by stacking 2.1 trapezoidal steps; Pre-compression deformation of ribs: Calculate the compression deformation of each trapezoidal step 2.1 based on the structural dimensions of the ribs, and perform pre-compression deformation on each trapezoidal step 2.1 according to the obtained compression deformation. Specifically, in this embodiment, the extrusion die in Embodiment 1 is used to extrude the ribs, and the optimal compression deformation amount group of each trapezoidal step 2.1 is calculated using the method in Embodiment 2. After the pressure plate in the extrusion component is tightly attached to the side of the corresponding trapezoidal step, the extrusion stroke of each extrusion component is set according to the optimal compression deformation amount group. Secondary milling of ribs: The extruded ribs are milled a second time using a milling machine to bring the ribs to the target size specifications. Creep aging treatment: The wall panel after secondary milling is subjected to creep aging forming in a hot autoclave; wherein the pressure in the hot autoclave is 1-2MPa, the temperature is 160-180℃, and the heat and pressure holding time is 16-18h.

[0067] This embodiment uses 2219 aluminum alloy as the material to compare the effects of different processing techniques. During friction stir additive manufacturing, the stirring head rotation speed was set to 350 r / min and the forward speed to 145 mm / min. During creep aging treatment, the pressure in the autoclave was set to 1 MPa, the temperature to 175℃, and the holding time to 16 h. The final rib shape was controlled to be consistent across all processing techniques. The comparison of the effects of different processing techniques is shown in Table 2. Table 2 Comparison of Processing Effects Table 2 shows that, regarding the mechanical properties of the ribs, process two lacks creep aging treatment, relying solely on extrusion for plastic strengthening to enhance strength. Without the cumulative effect of aging precipitation strengthening, the final yield strength and tensile strength are significantly lower than in process one. The higher elongation in process two is due to the lack of aging strengthening, which prevents excessive constraint on material plasticity. Regarding the difference in rib forming accuracy, process two lacks the surface fine-tuning effect of creep aging. The surface deviation after extrusion is only corrected by milling, which is insufficient to completely eliminate subsequent deformation caused by residual stress, resulting in a larger surface deviation.

[0068] Furthermore, regarding the mechanical properties of the ribs, creep aging in process three is performed before extrusion. The plastic deformation of extrusion destroys the precipitates formed during creep aging and reintroduces residual stress, weakening the aging strengthening effect and resulting in lower yield strength and tensile strength compared to process one. Simultaneously, because the extrusion process damages the aged microstructure without subsequent aging repair, the material's plasticity deteriorates, leading to lower elongation. Regarding the difference in rib forming accuracy, creep aging in process three is performed before extrusion. The plastic deformation of extrusion alters the already finely tuned profile, making subsequent milling difficult to fully correct, resulting in excessive internal stress and thus a greater profile deviation than in process one.

[0069] In contrast, in process one, milling is performed after additive manufacturing to remove surface defects and stress layers, providing high-quality high-gluten billets for extrusion. Then, extrusion plastic deformation refines the grains and eliminates internal defects, while initial shaping significantly improves strength and reduces surface deviation. Next, secondary milling is performed to refine the dimensions, providing a high-precision reference for creep aging. Finally, under creep aging treatment, strength is further improved through aging precipitation strengthening, while creep deformation finely adjusts the surface and eliminates residual stress, ultimately achieving optimal mechanical properties (yield strength 320MPa, tensile strength 430MPa) and optimal forming accuracy (surface deviation ≤5mm).

[0070] The processing technology of this embodiment solves the problem of processing and forming high-ribbed wall panels. By using the extrusion die in Embodiment 1, it is possible to achieve individual pre-deformation control of the ribbed components, which solves the problem that existing pre-deformation methods such as rolling, roll forming, and stamping are not applicable to wall panels with grid ribs, thus improving the mechanical properties of the ribbed wall panels. At the same time, this embodiment uses friction stirring additive manufacturing to form high-ribbed blanks, which solves the problems of material waste and high manufacturing costs in the subtractive manufacturing process of the prior art. By compressing and deforming the additively formed ribs, the strength of the additive bonding surface can be improved, and the performance of the additive blank can be improved.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-ribbed wall panel manufacturing process using friction stir additive manufacturing, characterized in that, include: High-gluten billet is formed by friction stirring additive manufacturing: a high-gluten billet is formed on the wall panel (1) by solid-phase additive manufacturing using friction stirring solid-phase additive manufacturing equipment; High-gluten billet side milling: The high-gluten billet is milled using a milling machine to obtain a material with the following characteristics: A rib (2) is formed by stacking trapezoidal steps (2.1); wherein the cross section of the trapezoidal step (2.1) perpendicular to the length direction of the rib is an isosceles trapezoid, and between two adjacent trapezoidal steps (2.1), the lower base length of the isosceles trapezoid corresponding to the upper trapezoidal step (2.1) is less than the upper base length of the isosceles trapezoid corresponding to the lower trapezoidal step (2.1), wherein It is a natural number greater than or equal to 2; Pre-compression deformation of ribs: Calculate the compression deformation of each trapezoidal step (2.1) according to the structural dimensions of the ribs (2), and pre-compress each trapezoidal step (2.1) according to the obtained compression deformation. Secondary milling of ribs: The extruded ribs are milled a second time using a milling machine to bring the ribs to the target size specifications. Creep aging treatment: The wall panel after secondary milling is subjected to creep aging forming in an autoclave.

2. The processing technology according to claim 1, characterized in that, The specific process of the pre-extrusion deformation of the reinforcing ribs is as follows: S1. Obtain the parameters of each trapezoidal step (2.1) based on the structural dimensions of the rib (2). and And calculate the coefficients of each trapezoidal step (2.1). ; in, Indicates the first The initial length of the median of the isosceles trapezoid corresponding to each trapezoidal step (2.1), Indicates the first The initial cross-sectional area of ​​each trapezoidal step (2.1) along the vertical centerline of the reinforcing rib is numbered sequentially from top to bottom as follows: , ; S2. Set the compression deformation increment of the rib (2). and initial compressive deformation At the same time, ; S3. Calculate the compressive deformation of the reinforcing bar. The amount of compressive deformation of each trapezoidal step (2.1) Based on the compressive deformation of each trapezoidal step (2.1) Perform extrusion simulation on the reinforcing bars and output the simulation results; in, , Indicates the first Trapezoidal steps in the second simulation The amount of compressive deformation; S4. Determine if the termination condition is met. If not, let... , Then return to S3, and if the condition is met, proceed from... The group with the optimal compression deformation was selected from the simulation results. , ; S5. According to the optimal compression deformation group , to complete the compression of the rib (2).

3. The processing technology according to claim 2, characterized in that, The coefficient of the trapezoidal step (2.1) Represented as: in, and All are coefficients.

4. The processing technology according to claim 3, characterized in that, coefficient and The calculation method is as follows: For trapezoidal steps and Extrusion simulation was performed, in which trapezoidal steps were used. and The compression deformation in the extrusion simulation is all , Satisfying the trapezoidal steps and No damage occurred. and ; Measurement of trapezoidal steps Compression deformation and trapezoidal steps Compression deformation ; in, , , Trapezoidal steps The initial length of the median of the corresponding isosceles trapezoid. Trapezoidal steps after compression The length of the median of the corresponding isosceles trapezoid. Trapezoidal steps The initial length of the median of the corresponding isosceles trapezoid. Trapezoidal steps after compression The length of the median of the corresponding isosceles trapezoid; Calculate trapezoidal steps coefficient and trapezoidal steps coefficient ;in, , ; Construct the system of equations as follows Calculate the coefficients and The value; in, Trapezoidal steps before compression The initial cross-sectional area along the vertical centerline of the reinforcing bar. Trapezoidal steps before compression The initial cross-sectional area along the vertical centerline of the reinforcing bar.

5. The processing technology according to claim 2, characterized in that, Step S4 specifically involves: If Then let , Then return to S3, otherwise start from... The group with the optimal compression deformation was selected from the simulation results. , , This represents the maximum compressibility deformation of the stiffener.

6. The processing technology according to claim 5, characterized in that, The maximum compressibility deformation of the rib Represented as: in, The initial length of the median of the isosceles trapezoid corresponding to the uppermost trapezoidal step. Let be the initial length of the median of the isosceles trapezoid corresponding to the lowest trapezoidal step. The coefficient of the lowest trapezoidal step (2.1).

7. The processing technology according to claim 2, characterized in that, Step S4 specifically involves: determining whether the rib has failed based on the current simulation results; if the rib has not failed, then... , Then return to S3; if damage occurs, then from... The group with the optimal compression deformation was selected from the simulation results. , .

8. The processing technology according to claim 2, characterized in that, Step S5 specifically involves simultaneously applying compressive forces along their respective normal directions to both sides of each trapezoidal step (2.1) to complete the compression of the rib (2); wherein, the amount of compression deformation of the sides of each trapezoidal step (2.1) from top to bottom is controlled sequentially as follows: The side refers to the plane on which the waist of the isosceles trapezoid corresponding to the trapezoidal step (2.1) is located.

9. The processing technology according to claim 2, characterized in that, from When selecting the optimal compression deformation group from the simulation results, the optimal compression deformation group is the one where the ribs deform uniformly as a whole and there is no stress concentration or rib failure.

10. The processing technology according to any one of claims 1-9, characterized in that: The stirring head of the friction stir solid additive manufacturing equipment rotates at a speed of 300-400 r / min and advances at a speed of 135-155 mm / min. The pressure inside the autoclave is 1-2 MPa, the temperature is 160-180℃, and the heat and pressure holding time is 16-18 hours.

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