Continuous fiber-reinforced three-dimensional printing process, embedding method, and software development method

Abstract

The application relates to a continuous fiber reinforced three-dimensional printing process, an embedding method and a software development method, and the process comprises the following steps: three-dimensional modeling of a target part body to obtain a target part body model; designing a CF reinforcement scheme according to the target part body to obtain a CF reinforcement path; setting a printing process parameter on the CF reinforcement path to obtain a three-dimensional CF distribution space; performing a Boolean subtraction operation on the target part body model and the CF distribution space to obtain a resin matrix part model; performing equal-thickness slicing on the resin matrix part model by using slicing software to obtain resin G-Code; generating continuous fiber G-Code according to the CF reinforcement path; inserting the continuous fiber G-Code into the resin G-Code according to the multiple relationship of the equal-thickness slicing to obtain composite G-Code; and performing three-dimensional printing according to the composite G-Code by using a printer to obtain a continuous fiber reinforced part. Compared with the prior art, the application has the advantages that the compactness of the reinforced part is ensured, and the printing is not limited by the geometric shape and height of the part.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of continuous fiber composite material FDM printing technology, in particular to a continuous fiber reinforced three-dimensional printing process, an embedding method and a software development method. BACKGROUND

[0002] Although the traditional Fused Deposition Modeling (FDM) is flexible, due to the mechanical properties of the thermoplastic resin materials (such as engineering plastic ABS, polylactic acid PLA, etc.) commonly used, the printed parts cannot withstand high load conditions. Although the parts made of metal materials used in traditional machining have high strength, the finished part quality is large, and it is difficult to process complex parts. The emergence of continuous fiber composite material FDM printing technology fully integrates the advantages of the two: this printing fully plays the advantage of FDM printing flexibility, and adds continuous fibers (CF) to the resin part to enhance the relatively low quality resin matrix printing part to provide high strength comparable to metal, greatly improving the part quality efficiency. The core and difficulty of this technology is the continuous fiber reinforced printing process, that is, how to perfectly lay the CF in the resin part without affecting the overall shape of the part and ensuring that the CF is firmly combined with the resin. SUMMARY

[0003] The purpose of the present application is to overcome the defects of the prior art and provide a continuous fiber reinforced three-dimensional printing process, an embedding method and a software development method, which perfectly lay the CF in the resin part without affecting the overall shape of the part and ensuring that the CF is firmly combined with the resin.

[0004] The purpose of the present application can be achieved by the following technical solutions:

[0005] A continuous fiber reinforced three-dimensional printing process, comprising the following steps:

[0006] Three-dimensional modeling of the target part body to obtain a target part body model;

[0007] Designing a CF reinforcement scheme according to the target part body to obtain a CF reinforcement path;

[0008] Setting corresponding printing process parameters on the CF reinforcement path to obtain a three-dimensional CF distribution space; performing a Boolean subtraction operation on the target part body model and the CF distribution space to obtain a resin matrix part model with a reserved fiber filling position;

[0009] Using slicing software to slice the resin matrix part model at equal thickness to obtain a resin G-Code of the resin matrix model;

[0010] generating continuous fiber G-Code according to the CF enhanced path;

[0011] inserting the continuous fiber G-Code into resin G-Code according to the multiple relationship of the equal-thickness slicing, to obtain composite G-Code integrating resin and continuous fiber;

[0012] using a continuous fiber reinforced composite material printer to perform three-dimensional printing according to the composite G-Code, to obtain a continuous fiber reinforced part.

[0013] Further, the equal-thickness slicing is slicing according to an integer multiple relationship between the resin layer thickness and the continuous fiber layer thickness.

[0014] Further, if the CF enhancement scheme contains multiple intersecting paths, multiple CF enhanced paths are generated according to the intersecting paths, and each CF enhanced path is alternately stacked to obtain the CF distribution space; multiple continuous fiber G-Code is generated according to each CF enhanced path, and is inserted into the resin G-Code layer by layer, to obtain the composite G-Code.

[0015] The application also provides an embedding method of a continuous fiber reinforced three-dimensional printing process, which is used for embedding continuous fiber into a resin matrix during a continuous fiber reinforced three-dimensional printing process, and the method comprises:

[0016] a starting point pressing step: adjusting the structure at the starting point of each continuous fiber path, so that each fiber is pressed into the resin matrix when starting printing.

[0017] Further, when the starting point of the continuous fiber path is a blind end, the starting point pressing step comprises:

[0018] moving the starting end of the CF reserved groove in each layer of resin matrix to the fiber direction, and the moving distance is determined according to the type of continuous fiber and its process parameters.

[0019] Further, when the starting point of the continuous fiber path is a non-blind end, and there is another continuous fiber path adjacent to the current continuous fiber path, a step or a protrusion is arranged at the corresponding position of the CF reserved space in the resin matrix, and the size of the step or the protrusion is determined according to the type of continuous fiber and its process parameters.

[0020] Further, the method further comprises:

[0021] an asymptotic introduction step: for the case that the nozzle of the three-dimensional printer is perpendicular to the printing plane, before printing the continuous fiber, a pre-extrusion action is performed to extrude the continuous fiber out of the nozzle outlet by an additional length ΔE, and then the continuous fiber is embedded after being bent.

[0022] Further, when printing the continuous fiber, the printing path starting point of the continuous fiber is M(x, y, z), the compensation path starting point of the pre-extrusion action is set as N(x+Δx, y+Δy, z+Δz), then the oblique downward straight line motion action from N point to M point is performed, the pre-extruded fiber with the length of ΔE is bent in the direction of the printing path starting point of the continuous fiber, and the continuous fiber is introduced into the resin matrix through the plane heat pressing at the nozzle outlet.

[0023] Further, the vector direction composed of Δx and Δy should be opposite to and on the same line with the printing direction at the printing path starting point of the continuous fiber, and the compensation path starting point satisfies:

[0024]

[0025] Δz> ΔE

[0026] r≥ ΔE

[0027] In the formula, r is the radius of the heat pressing plane at the nozzle outlet of the continuous fiber.

[0028] The application also provides a software development method of the continuous fiber reinforced three-dimensional printing process, comprising the following steps:

[0029] A plurality of software modules are set, and each software module is spliced according to actual needs to obtain complete composite codes of resin and fiber, and the plurality of software modules comprise:

[0030] A Start module is used for initialization work, and after execution, the printer enters a state of waiting for printing;

[0031] An End module is used for head-tail work, and after execution, the printer stops working;

[0032] A Resin module is used for formal printing of the resin matrix and auxiliary operation in the printing process;

[0033] A CF module is used for formal printing of the CF and auxiliary operation in the printing process;

[0034] A Resin2CF module is used for conversion operation from printing of the resin matrix to printing of the CF;

[0035] A CF2Resin module is used for conversion operation from printing of the CF to printing of the resin matrix.

[0036] Compared with the prior art, the application has the following advantages:

[0037] (1) The continuous fiber reinforced three-dimensional printing process of the present invention proposes an equal-thickness embedded printing process. By printing intersecting CF paths in layers, a flat and dense surface can be obtained after each layer of CF is embedded. This not only ensures the density of the reinforced parts, but also makes the printing not limited by the geometric shape and height of the parts, and also brings more possibilities for the design of CF reinforcement paths.

[0038] (2) The embedding method proposed in the present invention creates a small range of overlap between the path and the resin matrix part model at the printing starting point of each CF path, so that each fiber can be pressed into the matrix at the beginning of printing, and fully contact and fuse with the matrix resin material to improve the starting point bonding effect, which not only ensures smooth filament output at the starting point, but also provides a guarantee for the smooth laying and bonding of subsequent CF.

[0039] (3) The embedding method of the present invention also takes into account the problem that since most of the nozzles of the 3-axis 3D printer are perpendicular to the printing plane, this poses a great challenge to the bonding between the vertically extending continuous fibers and the horizontal resin matrix. A gradual introduction strategy is proposed. Before preparing to print the CF, a pre-extrusion action is performed to bend the pre-extruded fibers along the starting direction of the CF path, and then hot-press them into the resin matrix through the plane at the nozzle outlet to complete the CF introduction, so that the CF and the resin matrix are tightly combined, thereby improving the printing success rate and the CF embedding quality.

[0040] (4) The present invention also proposes a software development method for the continuous fiber reinforced three-dimensional printing process. Through modular software development logic, modules are spliced ​​according to specific needs to obtain corresponding codes, thereby improving code development efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of the overall process of a continuous fiber reinforced three-dimensional printing process provided in an embodiment of the present invention;

[0042] FIG2( a ) is a first exemplary diagram illustrating a case where the concept of “equal layer thickness” is included in an embodiment of the present invention;

[0043] FIG2( b ) is a second example diagram illustrating a case where the concept of “equal layer thickness” is included in an embodiment of the present invention;

[0044] FIG2( c ) is a third example diagram illustrating a case where the concept of “equal layer thickness” is included in an embodiment of the present invention;

[0045] Figure 3 A schematic diagram of a regular hexagonal prism model provided in an embodiment of the present invention;

[0046] Figure 4 A schematic diagram of drawing three enhancement curves provided in an embodiment of the present invention;

[0047] Figure 5 Fig. 1 is a schematic diagram of a PLA base model provided in an embodiment of the present application;

[0048] Figure 6 Fig. 2 is a schematic diagram of a three-path fiber sequential layer-embedding printing provided in an embodiment of the present application;

[0049] Fig. 7(a) is a schematic diagram of a pressing-in method with a blind end as a path starting point provided in an embodiment of the present application;

[0050] Fig. 7(b) is a schematic diagram of a pressing-in method with a non-blind end as a path starting point provided in an embodiment of the present application;

[0051] Figure 8 Fig. 8 is a schematic diagram of a gradual introduction strategy compensation path provided in an embodiment of the present application;

[0052] Figure 9 Fig. 9 is a schematic diagram of a gradual introduction process principle provided in an embodiment of the present application, from fiber pre-extrusion, to gradual bending and hot pressing pre-extruded fiber, to finally complete the process of fiber introduction;

[0053] Figure 10 Fig. 10 is a schematic diagram of a modular G-Code integration logic provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0055] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0056] It should be noted that: similar labels and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0057] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the application is usually placed, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0058] In addition, the terms "horizontal", "vertical" and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined. For example, "horizontal" only means that it is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0059] Embodiment 1

[0060] The present embodiment provides a continuous fiber reinforced three-dimensional printing process, which comprises remodeling a target part, removing a pre-designed CF distribution space on the body model thereof by Boolean operation, thereby forming a resin matrix part model with reserved CF filling grooves, slicing the resin model according to the CF target printing layer thickness, generating resin matrix and CF part G-Code respectively by using existing slicing software or other G-Code generation modules, and realizing the in-layer alternating printing of the matrix resin and the CF by interpenetrating and integrating the G-Code of the two according to the corresponding layer thickness. Finally, the CF is embedded into the resin matrix in each layer groove reserved for it.

[0061] The technical details of the present application include three aspects of process flow, embedding strategy and software development, which will be described in detail below.

[0062] I. Process flow

[0063] The process flow of the present application is shown in Figure 1 The specific steps include:

[0064] Step 1: CAD three-dimensional modeling of the target part body.

[0065] Step 2: Design the CF reinforcement scheme according to the target part, and then obtain the CF reinforcement path. The source of the path includes but is not limited to CAD manual design and drawing, and force flow trajectory line design and drawing obtained according to finite element analysis (FEA) calculation of the part, wherein the latter is described in detail in the same series patent "3D printing continuous fiber reinforcement path planning method based on principal stress trajectory line" (patent application publication number: CN113752560A), which is not the focus of this embodiment.

[0066] Step 3: Print process parameters such as layer thickness, line width, etc. are added to the one-dimensional CF enhanced path obtained in step 2 (the specific parameter values are determined by the properties of the fiber used, which is not required by the present invention), and a three-dimensional CF distribution space is obtained. The target part body model obtained in step 1 is subjected to a Boolean subtraction operation with the above CF distribution space, and a resin matrix part model with reserved fiber filling positions is obtained.

[0067] Step 4: Using the currently available relatively mature slicing software such as Simplify3D, Cura, etc., the resin matrix part model obtained in step 3 is sliced according to the CF printing process parameters such as layer thickness, and the G-Code of the resin matrix model is obtained. Note that the "equal layer thickness" described here is not limited to the case where the resin layer thickness is equal to the CF layer thickness, but also includes the case where the resin layer thickness and the CF layer thickness form an integer multiple relationship. For example: if the CF printing layer thickness requirement is 0.2mm, then the resin slicing layer thickness is selected as 0.1mm, 0.2mm, 0.4mm, etc., which respectively corresponds to: every 2 layers of resin embedded with 1 layer of CF, every 1 layer of resin embedded with 1 layer of CF, and every 1 layer of resin embedded with 2 layers of CF, etc., which are all included in the concept of "equal layer thickness" described in this embodiment, as shown in Figures 2(a)-2(c)

[0068] Step 5: Through the continuous fiber G-Code generation module, the G-Code of the CF enhanced path generated in step 2 is generated.

[0069] Step 6: Through the G-Code integration module, the resin G-Code generated in step 4 and the continuous fiber G-Code generated in step 5 are inserted according to the "equal layer thickness" multiple relationship described in step 4, and G-Code modification and post-processing are performed according to the actual printing situation, and finally the composite G-Code of the resin and CF is obtained.

[0070] Step 7: The composite G-Code obtained in step 6 is handed over to the continuous fiber reinforced composite material printer for printing. Since the resin matrix part obtained in step 3 has reserved CF embedding spaces consistent with the enhanced path, when the resin matrix is actually printed, a groove with a depth equal to the CF printing layer thickness will be presented after each layer (or several layers) of resin is printed, and then the CF will be filled into the groove reserved for it according to the path "equal layer thickness", forming a flat and dense surface to facilitate the printing of the next layer (or several layers). In this way, the CF is embedded into the resin matrix layer by layer with equal layer thickness, and the part printing is completed.

[0071] ​Special Note: This process is suitable for embedding CF reinforcement in resin parts. In particular, thanks to the "equal layer thickness" strategy proposed in this embodiment, this process is particularly suitable for cases where the CF reinforcement path has one or more intersections (such as triangular mesh, cross intersection, etc.), and the higher the total height of the embedded part, the more significant the advantages of this strategy. The current existing ironing process handles CF path intersections by forcibly pressing two CF segments together at high temperature through the print head. Since the number of layers of fiber stacking at the intersection is multiplied by the number of ordinary path layers, as the printing height increases, a noticeable protrusion will inevitably form at the path intersection, and even shear and scratch phenomena will occur. Both reduce the quality of fiber reinforcement and limit the overall printing height of the part. In contrast, the equal layer thickness embedding printing process proposed in this embodiment can obtain a smooth and dense surface after each layer of CF embedding, ensuring the density of the reinforced part, allowing printing to be free of geometric shape and height restrictions, and also providing more possibilities for CF reinforcement path design.

[0072] The following is a specific embodiment: using continuous carbon fiber (CCF) to reinforce a regular hexagonal prism PLA part to assist in explaining the above process.

[0073] Step 1: As shown in Figure 3 , a three-dimensional model of a regular hexagonal prism is created.

[0074] Step 2: The hexagonal prism is to be reinforced with a triangular mesh path. The two-dimensional reinforcement path curve is manually drawn in the Rhino platform. Note that the common triangular mesh is composed of three directions of -120°, 0°, and -120° serpentine trajectories, forming multiple intersections. The traditional ironing process will forcibly compress the three direction printing paths into one layer, which will cause obvious protrusions and shear scratches at the intersection. The "equal layer thickness" strategy divides the triangular mesh into three layers according to the direction and prints them separately, then stacks them, and processes the intersection layers to ensure the flatness and fiber filling of the surface after each layer is printed. Therefore, when drawing the two-dimensional reinforcement path curve in this step, three curves should be drawn, corresponding to the filling angles of -120°, 0°, and -120°. The three curves are drawn as shown in Figure 4 .

[0075] Step 3: In this example, the CCF printing layer thickness is 0.2mm, and the line width is 1mm. In the regular hexagonal prism model of step 1, the CCF embedding space is removed according to the three routes drawn in step 2, and the pure PLA base part model is obtained, as shown in Figure 5 .

[0076] Step 4: Using Simplify3D slicing software, the PLA matrix model generated in step 3 is "equal layer thickness" sliced according to the printing layer thickness of CCF 0.2mm, and then the PLA G-Code is obtained.

[0077] Step 5: Through the continuous fiber G-Code generation module based on Rhino-Grasshopper platform independently developed, the three paths drawn in step 2 are respectively converted into corresponding CCF G-Code.

[0078] Step 6: Through the G-Code integration module based on Rhino-Grasshopper platform independently developed, the PLA G-Code obtained in step 4 and the CCF G-Code obtained in step 5 are inserted and modified according to the layer number, and the final PLA-CCF composite G-Code is obtained.

[0079] Step 7: The PLA-CCF composite G-Code is handed over to the TOYI-43V1 continuous fiber reinforced composite material printer independently developed, and finally the CCF is embedded into the PLA matrix part according to the designed three paths with equal layer thickness and layer by layer, completing the CCF reinforced printing, as shown in Figure 6

[0080] II. Embedding strategy

[0081] In addition to the "equal layer thickness" overall embedding strategy mentioned in the process flow, this part will further explain the detailed processing strategy of CF in actual printing, aiming to make CF and resin matrix combine closely, improve the printing success rate and CF embedding quality.

[0082] • Content 1: Start point pressing strategy

[0083] The start point pressing strategy refers to: in the printing start point part of each CF path, a small range of path is made to coincide with the resin matrix part model, so that each fiber is pressed into the matrix when starting to print, and fully contacts and fuses with the matrix resin material to improve the start point bonding effect, which not only ensures the smooth starting point wire output, but also provides protection for the smooth laying and bonding of subsequent CF.

[0084] ​The starting point pressing-in method includes but is not limited to: when the starting point of the continuous fiber path is a blind end, the starting end of the CF reserved groove in each layer of resin matrix should be moved a proper distance in the fiber direction (the distance should be determined according to the type of continuous fiber used and its process parameters, too large will cause material overflow to fill the plane, too small will affect the pressing-in effect. It is recommended to choose one times the printing line width), as shown in Figure 7(a); when the starting point of the continuous fiber path is not a blind end and there are other fiber paths closely adjacent to it nearby, a step or protrusion should be set at the corresponding position of the CF reserved space in the resin matrix (the size of the step or protrusion is also determined according to the type of continuous fiber used and its process parameters), to provide a CF starting point pressing-in, as shown in Figure 7(b).

[0085] • Content 2: asymptotic introduction strategy

[0086] Since the nozzle of the 3-axis three-dimensional printer is more than the printing plane perpendicular, it brings great challenges to the bonding between the vertically extended continuous fiber and the horizontal resin matrix. To solve this problem, the present application proposes an "asymptotic introduction" strategy. The specific steps are as follows:

[0087] Step 1: Before printing CF, perform a pre-extrusion action, in addition to compensating for the distance from the cutting mechanism to the nozzle outlet, extrude an additional distance to extend the CF out of the nozzle outlet by a certain length ΔE.

[0088] Step 2: A certain compensation is made before the starting point of the CF printing path. Let the starting point of the printing path be M(x, y, z), and the starting point of the compensation path be N(x+Δx, y+Δy, z+Δz), perform a diagonal downward straight line motion action from N point to M point, and the compensation path is shown in Figure 8 By compensating for this action, the length ΔE of the fiber pre-extruded in step 1 can be gradually bent along the CF path starting point direction while the nozzle gradually approaches the M point, and the CF introduction is completed by the plane heat pressing into the resin matrix at the nozzle outlet, as shown in the process principle diagram Figure 9 Note: The vector composed of Δx and Δy should be opposite to and on the same straight line as the printing direction at the starting point of the CF path, and the size of the vector should satisfy the following condition: Δxy>Δz. In addition, in order to ensure that the CF can be bent smoothly, it is necessary to satisfy: Δz>ΔE. At the same time, in order to ensure that the bent fiber can be completely heat pressed by the nozzle plane without being raised, it is necessary to satisfy: r≥ΔE, where r is the heat pressing plane radius at the CF nozzle outlet.

[0089] III. Software development

[0090] In order to adapt to the above process strategy, the embodiment proposes a special software development scheme. Different from the relatively mature FDM slicing software on the market, the main function of the software is not the path planning of the resin matrix, but how to integrate the CF track into the resin matrix whose path has been planned, and then generate a composite G-Code which can be directly handed over to the printer. Its functions include but are not limited to: the continuous fiber G-Code generation module described in "process flow step 5", which is used to convert the CF enhancement path obtained in multiple ways into corresponding CF G-Code; the G-Code integration module described in "process flow step 6". For the G-Code integration module, the embodiment proposes a modular software development logic: the composite G-Code is divided into six modules according to the function: Start, End, Resin, CF, Resin2CF, CF2Resin. The following is an introduction to each module.

[0091] Start: including three-axis zero, setting unit, fan and heat bed opening and other initialization work. This module always appears at the front end of the complete G-Code and only appears once. After the module is executed, the printer enters the printing state.

[0092] End: including three-axis zero, closing the motor and fan and other finishing work. This module always appears at the end of the complete G-Code and only appears once. After the module is executed, the printer stops working.

[0093] Resin: including resin matrix formal printing related code and back-pumping, compensation and other auxiliary operations. Among them, the formal printing code, that is, the path planning part can be generated by any FDM slicing software, such as Simplify3D, which is not required in the embodiment.

[0094] CF: including CF formal printing related code and pre-extrusion, asymptotic introduction and other auxiliary operations required in "embedding strategy content 2".

[0095] Resin2CF and CF2Resin: these two are conversion modules, including switching nozzles and their accompanying related operations, such as wiping, switching double-head temperature, etc. Whenever the code involves material switching, these two modules need to be inserted between the Resin module and the CF module to connect.

[0096] The complete resin-CF composite code is spliced by the above six modules in a certain order, each module is the smallest unit divided according to the function and not suitable for division. If there are special needs, appropriate modules can also be added or modified according to the above logic, which are all within the scope of the software development idea described herein. The specific splicing rule is: the Start and End modules are placed at the beginning and the end, and the middle layers are spliced in order according to the planned printing order. If the material of adjacent modules changes, a corresponding conversion module needs to be inserted between the two blocks. The schematic flow chart is shown in Figure 10 .

[0097] For example, if a CF needs to be inserted into the second layer of a three-layer resin matrix, the module splicing order is:

[0098] Start-Resin1-Resin2-Resin2CF-CF2-CF2Resin-Resin3-End

[0099] The preferred embodiments of the application are described in detail above. It should be understood that those skilled in the art can make many modifications and changes without creative labor based on the concept of the present application. Therefore, any technical solution obtained by logical analysis, reasoning or limited experiment based on the existing technology according to the concept of the present application shall be within the protection scope determined by the claims.

Claims

1. A continuous fiber-reinforced three-dimensional printing process, characterized by, The method comprises the following steps: Three-dimensional modeling of the target part body is performed to obtain a target part body model; A CF reinforcement scheme is designed according to the target part body, and then a CF reinforcement path is obtained; A corresponding printing process parameter is set on the CF reinforcement path to obtain a three-dimensional CF distribution space; Boolean subtraction is performed on the target part body model and the CF distribution space to obtain a resin matrix part model with a reserved fiber filling position; The resin matrix part model is sliced by an equal layer thickness slicing software to obtain a resin G-Code of the resin matrix model, and the equal layer thickness slicing is performed according to an integral multiple relationship between a resin layer thickness and a continuous fiber layer thickness; A continuous fiber G-Code is generated according to the CF reinforcement path; The continuous fiber G-Code is inserted into the resin G-Code according to the multiple relationship of the equal layer thickness slicing to obtain a composite G-Code in which resin and continuous fibers are fused; A continuous fiber reinforced composite material printer is used to perform three-dimensional printing according to the composite G-Code to obtain a continuous fiber reinforced part.

2. The continuous fiber-reinforced three-dimensional printing process according to claim 1, wherein, If the CF reinforcement scheme comprises multiple intersecting paths, multiple CF reinforcement paths are generated according to the intersecting paths, and each CF reinforcement path is alternately and sequentially stacked to obtain the CF distribution space; multiple continuous fiber G-Codes are respectively generated according to each CF reinforcement path, and are inserted into the resin G-Code layer by layer according to the number of layers to obtain a composite G-Code.

3. A method of embedding of continuous fiber reinforced three-dimensional printing process according to any of claims 1-2, characterized in that, A method for embedding continuous fibers into a resin matrix during continuous fiber reinforced three-dimensional printing, the method comprising: A start point pressing step: adjusting the structure at the start point of each continuous fiber path so that each fiber is pressed into the resin matrix when printing starts.

4. The embedding method according to claim 3, wherein, When the start point of the continuous fiber path is a blind end, the start point pressing step comprises: Moving the start end of the CF reserved groove in each layer of the resin matrix to the fiber direction, and the moving distance is determined according to the type of continuous fiber and its process parameters.

5. The embedding method of claim 3, wherein, When the start point of the continuous fiber path is not a blind end, and there is another continuous fiber path adjacent to the current continuous fiber path, a step or a protrusion is arranged at the corresponding position of the CF reserved space in the resin matrix, and the size of the step and the protrusion is determined according to the type of continuous fiber and its process parameters.

6. The embedding method of claim 3, wherein, The method further comprises: Asymptotic introduction step: for the case of a nozzle of a three-dimensional printer perpendicular to the printing plane, a pre-extrusion action is performed, extruding the continuous fiber extra nozzle exit length before printing the continuous fiber and then bending and then performing the continuous fiber embedding process.

7. The embedding method according to claim 6, wherein, In printing the continuous fiber, the printing path starting point of the continuous fiber is The compensation path starting point of the pre-extrusion action is set as Then, the oblique downward straight line motion action from N point to M point is performed, and the pre-extrusion length is A section of fiber is bent in the direction of the printing path starting point of the continuous fiber, and the continuous fiber introduction is completed by the plane heat pressing at the nozzle outlet into the resin matrix.

8. The embedding method according to claim 7, wherein, Depend on and The direction of the constructed vector should be opposite to the printing direction at the starting point of the printing path of the continuous fiber and on the same straight line, and the starting point of the compensation path satisfies: ， In the formula, Rf is the hot flat plane radius at the exit of the continuous fiber nozzle.

9. A software development system for a continuous fiber-reinforced three-dimensional printing process according to any one of claims 1-2, characterized in that, The method comprises: A plurality of software modules are arranged, and each software module is spliced according to actual needs to obtain a complete composite code of resin and fiber, and the plurality of software modules comprise: A Start module for initialization, which makes the printer enter a ready-to-print state after execution; An End module for head and tail work, which makes the printer stop working after execution; A Resin module for formal resin matrix printing and auxiliary operations during printing; A CF module for CF formal printing and auxiliary operations during printing; A Resin2CF module for conversion from resin matrix printing to CF printing; A CF2Resin module for conversion from CF printing to resin matrix printing.

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