AU2018383793A1

AU2018383793A1 - Three-dimensional printing and forming method for fiber reinforced resin-based composite material

Info

Publication number: AU2018383793A1
Application number: AU2018383793A
Authority: AU
Inventors: Congze FAN; Feng Liu; Zhongde Shan; Li Zhan
Original assignee: Beijing Nat Innovation Institute Of Lightweight Ltd; Beijing National Innovation Institute of Lightweight Ltd
Current assignee: Beijing National Innovation Institute of Lightweight Ltd
Priority date: 2017-12-15
Filing date: 2018-12-11
Publication date: 2020-07-30
Anticipated expiration: 2038-12-11
Also published as: AU2018383793B2; CN108189386A; WO2019114709A1

Abstract

Disclosed in the present invention is a three-dimensional printing and forming method that may achieve a fiber reinforced resin-based composite material; by means of premixing short fibers of different contents and specifications in a resin material, the method three-dimensionally prints and forms composite material parts the reinforced composite effect of continuous fibers and short fibers of which is reinforced; thus, the overall mechanical properties thereof are improved. The method comprises a continuous fiber printing portion, a wire producing portion and a signal acquisition and control portion; short fibers of different specifications are added into a resin wire material in advance by means of the wire producing portion; during printing, a pre-mixed short-fiber resin wire material 5 and continuous fibers 6 of different specifications are fully mixed and soaked in a soaking chamber 7; continuous extrusion is implemented under the control of a wire feeding mechanism 4, and the wire is stacked in layers on a forming platform 10. The method has the advantages of printing precision being high and the fiber content of a molded part being high, and solves the problem wherein the Z-direction mechanical properties of three-dimensionally printed continuous fiber reinforced composite materials are poor, thereby improving the bonding quality between layers and single paths.

Description

Three-dimensional Printing and Forming Method for Fiber Reinforced Resin-based Composite Material

Technical Field The present invention relates to a field of 3D printing (additive manufacturing), and in particular to a three-dimensional printing and forming method that may achieve a resin-based composite material with reinforced composite effects of continuous fibers and short fibers.

Background Compared with a traditional cutting processing technology, a 3D printing (additive manufacturing) technology is a technology for additive-manufacturing solid parts in layers "from bottom to top" by using materials. The 3D printing technology is combined with existing industrial automation and computer aided design and the like, has the advantages of a high automation degree, a rapid forming speed and a high raw material utilization rate, and may achieve the digitization of designing and manufacturing processes. At present, the investment of the 3D printing technology is increased in countries around the world, and a variety of 3D printing methods is developed, and widely applied in the fields of electronic products, automobiles, aerospace, medical treatment, military industries, artistic designing and the like. A continuous fiber reinforced composite material has high specific strength and fatigue strength, excellent abrasive resistance and corrosion resistance, and high dimensional stability, and is widely applied in the fields of aerospace and automobile manufacturing and the like. Therefore, it becomes a research direction of multiple scientific research institutions that the 3D printing methods are used to achieve the formation of the continuous fiber reinforced composite material. At present, a method similar to Fused Deposition Modeling (FDM) is mainly used to melt and mix continuous fibers and resin filaments, and deposit layer by layer on a printing platform. A formed part manufactured by this method has excellent mechanical properties in a fiber spreading direction, and surpasses traditional three-dimensional weaving and knitting formed continuous fiber composite parts. However, it has a poorer performance in a Z direction (a normal direction of a printing layer), and has a poorer interlayer shearing strength and the poorer interface performance. In a working process of the formed part,

1 PN134251JXKX an external force often causes the cases of interlayer falling or breaking.

Summary A purpose of the present invention is to solve the above defects in a related art, and provide a composite material forming method that may achieve reinforced composite effects of continuous fiber and short fiber in a Z-direction, improving the interlayer shearing strength and the interface performance of a formed part, and having the characteristics of high printing precision and high fiber content of the formed part. In order to achieve the above purpose, the present invention adopts the following technical solution. Long fibers are cut into short fibers in preset length by using a fiber cutter 1, the short fibers are added to a pre-mixer 2 with a resin in preset model together, and it is pulled into a pre-mixed short fiber resin wire material 5 for subsequent printing by a wire producing machine 3. Multiple wire feeding mechanisms 4 may respectively pre mix the pre-mixed short fiber resin wire materials 5 in different short fiber dimensions and contents with continuous fibers 6 in a soaking chamber 7, adequately contacting and soaking, each fiber is wrapped by the resin as much as possible. A heating mechanism 8 is outside the soaking chamber 7, it controls a temperature field of an entire continuous fiber printing system, especially a length of a heating section, and may achieve rapid melting of the pre-mixed short fiber resin wire materials 5. A printing nozzle 9 with a special shape is connected under the soaking chamber 7, and may extrude a mixture of the continuous fibers and the resin in the case without damaging the fibers. The above soaking chamber 7, heating mechanism 8 and nozzle 9 are placed on a three-dimensional moving platform 10 after being combined, and may achieve three-dimensional precise movement. A signal acquisition and control portion 11 includes a control card 12, multiple temperature sensors 13, an image sensor 14, and a computer 15. The computer 15 is used to draw a three-dimensional model and generates a G code after slicing. The control card 12 controls statuses of different mechanisms in each printing link, such as, a wire feeding speed, a heating temperature, and a nozzle moving speed. The multiple temperature sensors 13 collect temperatures of the printing platform, the heating mechanism 8 and the nozzle 9 and upload to the computer 15 in real time. The image sensor 14 may monitor the printing effect in real time, and upload to the computer for modifying printing parameters, and it is used to form a closed-loop 2 PN134251JXKX system. The short fibers into which the continuous fibers are cut by using the fiber cutter 1 are 2 mm to 50 mm in dimension, and may be carbon fibers or glass fibers or organic fibers. The continuous fiber printing system may be provided with multiple wire feeding mechanisms 4 which respectively achieve fixed-speed wire feeding of multiple pre mixed short fiber resin wire materials 5 and the continuous fibers, herein, the multiple resins mainly refer to a polylactic acid (PLA), an acrylonitrile-butadiene-styrene copolymer (ABS), a polyimide (PI), and a polyether ether ketone (PEEK), the continuous fibers may be the carbon fibers or the glass fibers or the organic fibers in multiple specifications such as 1K, 3K, 6K and 11K. The beneficial effect of the present invention is as follows: the present invention creatively introduces the short fibers into a continuous fiber printing technology, there are randomly-oriented short fibers in two printing layers 16, and the short fibers are tightly combined with the upper and lower two layers through the resin, and they have multiple position forms between the layers. While the short fibers are overlapped in upper and lower two continuous fiber reinforced resin layers, they are Z-direction reinforced short fibers 17, and have a pinning effect. While an external force is applied to a Z-direction of the formed part, the short fibers may resist falling between the layers. While the short fibers are overlapped between a plurality of adjacent forming single paths 18, they are inter-single-path bonding reinforced short fibers 20, and the bonding strength in vertical direction between the single path and the single path is greatly increased. Furthermore, in the present invention, because the pre-mixed short fiber resin wire material 5 contains fibers in higher volume fraction, the continuous fibers added in a deposition process are combined, the fiber content in the formed part may be greatly improved, and more excellent mechanical properties may be acquired.

Brief Description of the Drawings The drawings forming a part of the present application in the specification are adopted to provide a further understanding to the present invention. Schematic embodiments of the present invention and descriptions thereof are adopted to explain the present invention and not intended to form improper limits to the present invention. In the drawings: Fig. 1 is a printing schematic diagram of the method of the present invention; 3 PN134251JXKX

Fig. 2 is a Z-direction interlayer bonding strength reinforcement schematic diagram of a composite material formed part; Fig. 3 is a bonding strength reinforcement schematic diagram between single path and single path of the composite material formed part; and Fig. 4 is a printing nozzle through hole type map. Herein, the above drawings include the following reference signs: 1. Fiber cutter, 2. Pre-mixer, 3. Wire producing machine, 4. Wire feeding mechanism, 5. Pre-mixed short fiber resin wire material, 6. Long fiber, 7. Soaking chamber, 8 Heating mechanism, 9. Nozzle, 10. Three-dimensional moving platform, 11. Signal acquisition and control portion, 12. Control card, 13. Temperature sensor, 14. Image sensor, 15. Computer, 16. Printing layer, 17. Z-direction reinforced short fiber, 18. Forming single path, and 20. Inter-single-path bonding reinforced short fiber.

Detailed Description of the Embodiments The technical solutions in embodiments of the present invention will be clearly and completely described below in combination with the drawings in the embodiments of the present invention. It is apparent that the described embodiments are only part of the embodiments of the present invention but not all of the embodiments. The following description of at least one exemplary embodiment is only illustrative actually, and is not used as any limitation for the present invention and the present application or use thereof. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative work shall fall within the scope of protection of the present invention. The present invention is further described in detail below in combination with the drawings. Referring to Fig. 1, long fibers are cut into short fibers in preset length by using a fiber cutter 1, the short fibers are added to a pre-mixer 2 with a resin in preset model together, and it is pulled into a pre-mixed short fiber resin wire material 5 for subsequent printing by a wire producing machine 3. Multiple wire feeding mechanisms 4 may respectively pre-mix the pre-mixed short fiber resin wire materials 5 in different short fiber dimensions and contents with continuous fibers 6 in a soaking chamber 7, adequately contacting and soaking, each fiber is wrapped by the resin as much as possible. A heating mechanism 8 is outside the soaking chamber 7, which controls a temperature field of an entire continuous fiber printing system, especially a length of a 4 PN134251JXKX heating section, and may achieve rapid melting of the pre-mixed short fiber resin wire materials 5. A printing nozzle 9 with a special shape is connected under the soaking chamber 7, and may extrude a mixture of the continuous fibers and the resin in the case without damaging the fibers. The above soaking chamber 7, heating mechanism 8 and nozzle 9 are placed on a three-dimensional moving platform 10 after being combined, and may achieve three-dimensional precise movement. A signal acquisition and control portion 11 includes a control card 12, multiple temperature sensors 13, an image sensor 14, and a computer 15. The computer 15 draws a three-dimensional model and generates a G code after slicing. The control card 12 controls statuses of different mechanisms in each printing link, such as, a wire feeding speed, a heating temperature, and a nozzle moving speed. The multiple temperature sensors 13 collect temperatures of the printing platform, the heating mechanism 8 and the nozzle 9 and upload to the computer 15 in real time. The image sensor 14 may monitor the printing effect in real time, and upload to the computer for modifying printing parameters, and it is used to form a closed-loop system. The short fibers into which the continuous fibers are cut by using the fiber cutter 1 are 2 mm to 50 mm in dimension, and may be carbon fibers or glass fibers or organic fibers. The continuous fiber printing system may be provided with multiple wire feeding mechanisms 4 which respectively achieve fixed-speed wire feeding of multiple pre mixed short fiber resin wire materials 5 and the continuous fibers, herein, the multiple resins mainly refer to a polylactic acid (PLA), an acrylonitrile-butadiene-styrene copolymer (ABS), a polyimide (PI), and a polyether ether ketone (PEEK), the continuous fibers may be the carbon fibers or the glass fibers or the organic fibers in multiple specifications such as 1K, 3K, 6K and 11K. The short fibers are introduced into a continuous fiber printing technology, there are randomly-oriented short fibers in two printing layers 16, and the short fibers are tightly combined with the upper and lower two layers through the resin, and they have multiple position forms between the layers. While the short fibers are overlapped in upper and lower two continuous fiber reinforced resin layers, they are Z-direction reinforced short fibers 17, and have a pinning effect. While an external force is applied to a Z-direction of the formed part, the short fibers may resist falling between the layers. While the short fibers are overlapped between a plurality of adjacent forming single paths 18, they are inter-single-path bonding reinforced short fibers 20, and the bonding strength in vertical direction between the single path and the single path is greatly increased. 5 PN134251JXKX

As shown in Fig. 1 to Fig. 4, the embodiment of the present invention provides a three-dimensional printing and forming method for a fiber reinforced resin-based composite material, including: a continuous fiber printing portion, a wire producing portion, and the signal acquisition and control portion 11; the continuous fiber printing portion includes the wire feeding mechanisms 4, the pre-mixed short fiber resin wire materials 5, the continuous fibers 6, the soaking chamber 7, the heating mechanism 8, the nozzle 9, and the three-dimensional moving platform 10, the wire producing portion includes the fiber cutter 1, the pre-mixer 2, and the wire producing machine 3, the signal acquisition and control portion includes the signal acquisition and control portion 11, the control card 12, the temperature sensors 13, the image sensor 14, and the computer 15. Atechnical solution of the present embodiment is applied, in the three-dimensional printing and forming method for the fiber reinforced resin-based composite material, the wire producing portion is included, it is mainly to achieve the formation of the pre mixed short fiber resin wire material 5, and it includes the fiber cutter 1, the pre-mixer 2 and the wire producing machine 3, the fiber cutter 1 is used to manufacture the short cut fibres which may be the carbon fibers or the glass fibers or the organic fibers. The short fibers are mixed with the resin in preset model in the pre-mixer 2, and the pre mixed short fiber resin wire material 5 is produced by the wire producing machine. As shown in Fig. 1, the continuous fibers are mechanically cut after being fed into the short fiber cutter 1, the short fibers with a length of 2 mm to 50 mm are formed, and a dimension range of the short fibers is in accordance with normal distribution. The short fibers and continuous resin particles are adequately and uniformly mixed in a fixed proportion by the pre-mixer 2, and a fiber agglomeration phenomenon may be prevented. A mixed material is formed into a uniform resin wire material in 1 mm to 3 mm of dimension by the wire producing machine 3, wire diameter and fiber content of the formed resin wire material may be adjusted according to requirements. The technical solution of the present embodiment is applied, in the three dimensional printing and forming method for the fiber reinforced resin-based composite material, the continuous fiber printing portion is designed, and it is mainly to achieve wire feeding of the pre-mixed short fiber resin wire material 5 and wire feeding of the continuous fibers 6, two materials are heated in the soaking chamber and adequately mixed and soaked, continuous printed on the forming three-dimensional moving platform 10 with a heating function, the short fiber reinforcement exists between the 6 PN134251JXKX continuous fiber printing layers and between the single paths in the formed part, and the two materials are connected together through the resin. As shown in Fig. 1, multiple wire feeding mechanisms 4 may respectively pre-mix the pre-mixed short fiber resin wire materials 5 in different short fiber dimensions and contents with continuous fibers 6 in the soaking chamber 7, adequately contacting and soaking, each fiber is wrapped by the resin as much as possible. The heating mechanism 8 is outside the soaking chamber 7, it controls a temperature field of an entire continuous fiber printing system, especially a length of a heating section, and may achieve rapid melting of the pre-mixed short fiber resin wire materials 5. The printing nozzle 9 with a special shape is connected under the soaking chamber 7, and may extrude a mixture of the continuous fibers and the resin in the case without damaging the fibers. The above soaking chamber 7, heating mechanism 8 and nozzle 9 are placed on the three-dimensional moving platform 10 after being combined, and may achieve three-dimensional precise movement. The technical solution of the present embodiment is applied, in the three dimensional printing and forming method for the fiber reinforced resin-based composite material, the signal acquisition and control portion 11 includes the control card 12, the multiple temperature sensors 13, the image sensor 14, and the computer 15. The computer 15 draws a three-dimensional model and generates a G code after slicing. The control card 12 controls statuses of different mechanisms in each printing link. The multiple temperature sensors 13 collect temperatures of the printing platform, the heating mechanism and the nozzle and upload to the computer in real time. The image sensor 14 may monitor the printing effect in real time, and upload to the computer for modifying printing parameters, and it is used to form a closed-loop system. In the present embodiment, the three-dimensional moving platform 10 has the heating function, and may prevent from generating defects such as warping in a printing process, a heating mode may be resistance wire heating or laser heating or roller heating. While the resistance wire heating is used, the resistance wire is positioned in the forming platform, and distributed in a certain mode, the surface of the platform is controlled to reach a preset temperature. While the laser heating or the roller heating is adopted, a formed layer is pre-heated by a laser or a roller, and then the composition material is printed on a pre-heated layer. In the present embodiment, the printing nozzle 9 has great flexibility in a size and a shape of a through hole, as shown in Fig. 4, it may be round, and a diameter is from 7 PN134251JXKX

0.1 to 2 mm; and it may be oval or chamfered rectangle, so as to achieve spray deposition of a resin and fiber mixture with a specific shape, and the orientation of the short fibers may also be limited in a certain degree by this mode. As shown in Fig. 2, there are randomly-oriented short fibers in two printing layers 16, and the short fibers are tightly combined with the upper and lower two layers through the resin, and they have multiple position forms between the layers. While the short fibers are overlapped in upper and lower two continuous fiber reinforced resin layers, they are Z-direction reinforced short fibers 17, and have a pinning effect. While an external force is applied to a Z-direction of the formed part, the short fibers may resist falling between the layers. As shown in Fig. 3, the randomly-oriented short fibers exist in two forming single paths 18 of printed continuous fiber reinforced resin, and the short fibers have multiple position forms between the single paths. While the short fibers are overlapped between a plurality of the adjacent forming single paths 18, they are inter-single-path bonding reinforced short fibers 20, and the bonding strength in vertical direction between the single path and the single path is greatly increased. It is to be noted that the continuous fiber reinforced composite material related to the present application includes the continuous fibers and a resin-based body, herein, the resin-based body includes a thermoplastic resin manufactured by a polylactic acid (PLA), an acrylonitrile-butadiene-styrene copolymer (ABS), a polyimide (PI), or a polyether ether ketone (PEEK), the continuous fibers include the carbon fibers, the glass fibers or the organic fibers, and the continuous fibers may be multiple specifications, such as 1K, 3K, 6K or 12K. The technical scheme of the present embodiment is applied, the short fibers and the resin may be adequately mixed in the soaking chamber 7, the mixing in different proportions may be achieved by adjusting a wire feeding speed, and a fiber volume fraction in a depositing layer is accurately controlled. Because the pre-mixed short fiber resin wire material 5 contains the fibers in higher volume fraction, the continuous fibers 6 added in a deposition process are combined, the fiber content in the formed part may be greatly improved, and more excellent mechanical properties may be acquired. It is to be noted that terms used herein are only adopted to describe specific implementation modes and not intended to limit exemplary implementation modes according to the present application. For example, singular forms, used herein, are also intended to include plural forms, unless otherwise clearly pointed out. In addition, 8 PN134251JXKX it is also to be and understood that terms "contain" and/or "include" used in the specification refer/refers to existence of features, steps, operations, apparatuses, components and/or combinations thereof. Unless otherwise specified, relative arrangements of components and steps elaborated in these embodiments, numeric expressions and numeric values do not limit the scope of the present invention. Furthermore, it is to be understood that for ease of descriptions, the size of each part shown in the drawings is not drawn in accordance with an actual proportional relation. Technologies, methods and devices known by those of ordinary skill in the art may not be discussed in detail. However, where appropriate, the technologies, the methods and the devices shall be regarded as part of the authorized description. In all examples shown and discussed herein, any specific values shall be interpreted as only exemplar values instead of limited values. As a result, other examples of the exemplary embodiments may have different values. It is to be noted that similar marks and letters represent similar items in the following drawings. As a result, once a certain item is defined in one drawing, it is unnecessary to further discus the certain item in the subsequent drawings. In the descriptions of the present invention, it will be appreciated that locative or positional relations indicated by "front, back, up, down, left, and right", "horizontal, vertical, perpendicular, and horizontal", "top and bottom" and other orientation terms are locative or positional relations shown on the basis of the drawings, which are only intended to make it convenient to describe the present invention and to simplify the descriptions without indicating or impliedly indicating that the referring device or element must have a specific location and must be constructed and operated with the specific location, and accordingly it cannot be understood as limitations to the present invention. The orientation terms "inside and outside" refer to the inside and outside relative to contours of each component itself. For ease of description, spatial relative terms such as "over", "above", "on an upper surface" and "upper" may be used herein for describing a spatial position relation between a device or feature and other devices or features shown in the drawings. It will be appreciated that the spatial relative terms aim to contain different orientations in usage or operation besides the orientations of the devices described in the drawings. For example, if the devices in the drawings are inverted, devices described as "above other devices or structures" or "over other devices or structures" will be located as "below other devices or structures" or "under other devices or structures". Thus, an 9 PN134251JXKX exemplar term "above" may include two orientations namely "above" and "below". The device may be located in other different modes (rotated by 90 degrees or located in other orientations), and spatial relative descriptions used herein are correspondingly explained. In addition, it is to be noted that terms "first", "second" and the like are used to limit parts, and are only intended to distinguish corresponding parts. Unless otherwise specified, the above words have no special meaning, therefore it may not be understood as the limitation to a scope of protection of the present invention. It is to be noted that terms used herein are only adopted to describe specific implementation modes and not intended to limit exemplary implementation modes according to the present application. For example, singular forms, used herein, are also intended to include plural forms, unless otherwise clearly pointed out. In addition, it is also to be understood that terms "contain" and/or "include" used in the specification refer/refers to existence of features, steps, work, apparatuses, components and/or combinations thereof.

10 PN134251JXKX

Claims

What is claimed is: 1. A three-dimensional printing and forming method for a fiber reinforced resin based composite material, wherein in order to achieve a printing effect of the method, a continuous fiber printing portion, a wire producing portion and a signal acquisition and control portion (11) are required to be designed; the continuous fiber printing portion mainly achieves wire feeding of a pre-mixed short fiber resin wire material (5) and wire feeding of a continuous fiber (6), two materials are heated in a soaking chamber and adequately mixed and soaked, continuous printed on a forming three dimensional moving platform (10) with a heating function, a short fiber reinforcement exists between continuous fiber printing layers and between single paths in a formed part, and the two materials are connected together through a resin; the wire producing portion is mainly used to form the pre-mixed short fiber resin wire material (5); and the signal acquisition and control portion (11) assists the continuous fiber printing portion systematically, and a working status of each link in a printing process is controlled in real time by parameter collection and analysis.
2. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1, wherein the wire producing portion comprises a fiber cutter (1), a pre-mixer (2) and a wire producing machine (3), the fiber cutter (1) is used to manufacture short-cut fibres in 2 mm to 50 mm of a length, the short-cut fibres are able to be carbon fibers or glass fibers or organic fibers; and the short fibers are mixed with a resin in preset model in the pre-mixer (2), and the pre-mixed short fiber resin wire material (5) is manufactured by the wire producing machine (3).
3. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1, wherein the continuous fiber printing portion comprises a plurality of wire feeding mechanisms (4), a soaking chamber (7), a heating mechanism (8), a printing nozzle (9), and a three-dimensional moving platform (10); the heating mechanism (8) controls a temperature field of the entire continuous fiber printing portion, controls a length of a heating section, and achieves rapid melting of the pre-mixed short fiber resin wire material (5); the pre mixed short fiber resin wire material (5) and the continuous fiber (6) are pre-mixed in the soaking chamber, adequately contacting and soaking, so each fiber is wrapped by a resin as much as possible, and extruded in a certain speed by the printing nozzle (9) with a specific structure; and the printing nozzle (9) is able to reduce a damage to

11 PN134251JXKX a fiber beam, and control a shape and a size of a forming single path.
4. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1, wherein the signal acquisition and control portion (11) comprises a control card (12), a plurality of temperature sensors (13), an image sensor (14), and a computer (15); the computer (15) is used to draw a three-dimensional model and generates a G code after slicing, and the control card (12) controls statuses of different mechanisms in each printing link; the plurality of temperature sensors (13) collect temperatures of the printing platform, the nozzle and the heating mechanism and upload to the computer (15) in real time; and the image sensor (14) is able to monitor the printing effect in real time, and upload data to the computer for modifying printing parameters, so as to form a closed-loop system.
5. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1 or 3, wherein the forming three dimensional moving platform (10) is provided with a heating function, and is able to prevent from generating defects such as warping in the printing process, a heating mode is able to be resistance wire heating or laser heating or roller heating; while the resistance wire heating is adopted, a resistance wire is disposed in the forming platform, and distributed in a certain mode, a surface of the platform is controlled to reach a preset temperature; and while the laser heating or the roller heating is adopted, a formed layer is pre-heated by a laser or a roller, and then a composition material is printed on a pre-heated layer.
6. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1 or 3, wherein the printing nozzle (9) has great flexibility in size and shape of a through hole, the through hole is able to be round, and a diameter is from 0.1 to 2 mm; and the through hole is able to be oval or chamfered rectangle, so as to achieve spray deposition of a resin and fiber mixture with a specific shape, and an orientation of short fibers are also able to be limited in a certain degree by this mode.
7. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1, wherein there are randomly oriented short fibers in two printing layers (16), and the short fibers are tightly combined with an upper and lower two layers through the resin, and it has a plurality of position forms between the layers, while the short fibers are overlapped in upper

12 PN134251JXKX and lower two continuous fiber reinforced resin layers, they are Z-direction reinforced short fibers (17), and has a pinning effect; and while an external force is applied to a Z-direction of the formed part, the short fibers are able to resist falling between the layers.
8. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1, wherein randomly-oriented short fibers exist in two forming single paths (18) of printed continuous fiber reinforced resin, and the short fibers have a plurality of position forms between the single paths, while the short fibers are overlapped between a plurality of adjacent forming single paths (18), they are inter-single-path bonding reinforced short fibers (20), and a bonding strength in a vertical direction between the single path and the single path is greatly increased.
9. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1 or 3, wherein the continuous fiber printing portion is able to be provided with a plurality of wire feeding mechanisms (4) which respectively achieve fixed-speed wire feeding of the pre-mixed short fiber resin wire material (5) and the continuous fibers (6), wherein, a plurality of resins mainly refer to a polylactic acid (PLA), an acrylonitrile-butadiene-styrene copolymer (ABS), a polyimide (PI), and a polyether ether ketone (PEEK), the continuous fibers are able to be carbon fibers or glass fibers or organic fibers in a plurality of specifications such as 1K, 3K, 6K and 11K.
10. The three-dimensional printing and forming method for the fiber reinforced resin-based composite material as claimed in claim 1 or 3, wherein long and short fibers and a resin are able to be adequately mixed in a soaking chamber (7), and mixing in different portions is achieved by adjusting a wire feeding speed, thereby a fiber volume fraction in a depositing layer is accurately controlled; and because the pre-mixed short fiber resin wire material (5) contains fibers in higher volume fraction, the continuous fibers (6) added in a deposition process are combined, the fiber content in a formed part is able to be greatly improved, and more excellent mechanical properties is able to be acquired.

13 PN134251JXKX

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