阅读说明：本技术 一种高性能纤维增强热塑性树脂基复合材料增材制造方法 (Additive manufacturing method of high-performance fiber-reinforced thermoplastic resin-based composite material ) 是由 单忠德 宋亚星 吴晓川 战丽 陈意伟 于 2020-04-23 设计创作，主要内容包括：一种高性能纤维增强热塑性树脂基复合材料增材制造方法,先对目标制件进行分层离散等处理,确定打印参数；制备特定尺寸增强体；内层喷嘴挤出复合材料进行基板打印；外层喷嘴进风口进风,气流经加热块加热成高温热流,增强体在投放口投放,随高温热流经外层喷嘴以一定角度附着在内层喷嘴挤出的复合材料上；激光按规划路径对扫描点进行预热处理,喷头同步进行打印；在道间相交处,附着在挤出材料上的增强体被动压入重叠处树脂里,完成一层的制造；在层层叠加过程中,附着在挤出材料上的增强体被动压入四周熔融树脂里,直到完成目标制件的增材制造。本发明可实现包含Z向层间结合性能在内的成形件整体结合性能提升的高性能制造。(A high-performance fiber reinforced thermoplastic resin matrix composite material additive manufacturing method comprises the steps of firstly carrying out layering dispersion and other treatments on a target workpiece, and determining printing parameters; preparing a specific size reinforcement; the inner layer nozzle extrudes the composite material to print the substrate; the air inlet of the outer layer nozzle is used for feeding air, the air flow is heated by the heating block to form high-temperature heat flow, the reinforcement body is put in the putting opening and attached to the composite material extruded by the inner layer nozzle at a certain angle along with the high-temperature heat flow through the outer layer nozzle; the laser carries out preheating treatment on the scanning points according to the planned path, and the spray heads synchronously carry out printing; at the intersection between the lanes, the reinforcement attached to the extruded material is passively pressed into the resin at the overlap to complete the fabrication of one layer; in the process of layer-by-layer stacking, the reinforcement attached to the extruded material is passively pressed into the surrounding molten resin until additive manufacturing of the target part is completed. The invention can realize high-performance manufacturing with improved integral bonding performance of the formed piece including Z-direction interlayer bonding performance.)

1. A high-performance fiber reinforced thermoplastic resin matrix composite material additive manufacturing method is characterized by comprising the following steps:

1) carrying out layered dispersion on the three-dimensional data of the target workpiece: performing discrete processing, path planning, process parameter setting and the like on the three-dimensional data of the target workpiece to obtain printing and manufacturing data;

2) preparation of the reinforcement (4): the reinforcement (4) is a thin rod with certain rigidity and limited length and diameter; cutting a wire with a specific diameter into a reinforcement (4) with a certain length; the material of the reinforcement (4) can be of three types: preparing unidirectional fiber composite wires with specific diameters, light nonferrous metal wires with specific diameters and fiber metal composite wires with specific diameters such as nickel-plated carbon fibers and copper-plated carbon fibers by a pultrusion process according to the types of resin and fibers of target workpieces;

3) printing substrate (3): starting the inner layer by the double-layer nozzle, and extruding the molten resin-based composite material by the inner-layer nozzle (6) to print the substrate (3);

4) manufacturing of a target product: the inner layer and the outer layer are started simultaneously by the double-layer nozzle, air is fed into an air inlet (1) of the outer-layer nozzle (5), airflow is heated into high-temperature heat flow by a heating block (2) above the nozzle, the reinforcement (4) prepared in the step 2) is put in at the moment, and the reinforcement (4) is attached to the resin-based composite material extruded at the inner-layer nozzle at a certain angle along with the high-temperature heat flow; preheating the pre-scanning point by the laser according to the planned path in the step 1), and printing by the spray head according to the planned path and the printing parameters in the step 1); during the crossing of the tracks, the reinforcement (4) attached to the extruded material is passively pressed into the resin at the overlap, completing the production of a layer;

5) and (4) repeating the step 4), and in the process of laminating layer by layer, passively pressing the reinforcing bodies (4) attached to the extruded material into the surrounding molten resin until the additive manufacturing of the target part is completed.

2. The additive manufacturing method of the high-performance fiber-reinforced thermoplastic resin-based composite material according to claim 1, wherein the fiber in the fiber-reinforced resin-based composite material is one or more of short fiber, fixed length continuous fiber and continuous fiber, the fiber material is suitable for carbon fiber, aramid fiber, glass fiber and the like, and the resin matrix is suitable for thermoplastic resin such as polylactic acid, polyethylene, nylon (6/66), ABS and the like.

3. The additive manufacturing method of high performance fiber reinforced thermoplastic resin based composite material according to claim 1, wherein the process parameter settings include but are not limited to desired nozzle aperture, scanning pitch, scanning speed, layer thickness, etc.

4. The additive manufacturing method of the high-performance fiber reinforced thermoplastic resin-based composite material as claimed in claim 1, wherein the diameter of the prepared reinforcement is 0.05-0.5 mm, the corresponding length is 0.1-1mm, and the size of the reinforcement is selected to be related to the diameter of the nozzle; different sizes of reinforcement members can be placed in different areas during the printing process.

5. The method for manufacturing the high-performance fiber reinforced thermoplastic resin-based composite material additive according to claim 1, wherein the reinforcement bodies not only have a connection function between layers, but also have a connection function between scanning tracks.

6. The additive manufacturing method of a high performance fiber reinforced thermoplastic resin based composite material according to claim 1, wherein the double layer nozzle can be replaced with different size models.

7. The additive manufacturing method of high-performance fiber reinforced thermoplastic resin-based composite material according to claim 1, wherein the air inlet of the outer layer of the double-layer nozzle is controllable, and the air inlet speed, the air inlet temperature and the air inlet direction are not limited.

8. The additive manufacturing method of a high performance fiber reinforced thermoplastic resin based composite material according to claim 1, wherein there is no spatial interference between the print head and the laser preheater.

Technical Field

The invention relates to a material additive manufacturing method of a high-performance fiber-reinforced thermoplastic resin-based composite material, belonging to the technical field of advanced manufacturing.

Background

The fiber reinforced resin matrix composite material is composed of fiber materials and matrix materials, and has the advantages of light weight, high strength, convenient forming, corrosion resistance and the like. The method is mainly applied to the fields of aerospace, military, traffic and the like. The fiber-reinforced composite materials can be classified into continuous fiber-reinforced composite materials and short fiber-reinforced composite materials according to the length of the fiber material. At present, aiming at the manufacturing of the material, in addition to the traditional fiber laying manufacturing technology, the additive manufacturing technology based on the melt extrusion principle is a key development trend in the future by means of easier forming of complex structures, no need of dies and relatively simple realization of the process.

However, the principle characteristic of 'layer-by-layer stacking' of the technology causes that the layers are only bonded by resin, the bonding property is poor, the Z-direction performance of a formed part is limited, and the performance advantage of the material in application is further restrained. In order to solve the problem of poor interlayer bonding, a fiber rod is embedded in the Z direction by a method comprising the following steps of driving by using a nail gun or a preset hot gun; continuous fibers have also been introduced to achieve Z-direction reinforcement in combination with fiber placement techniques or fiber weaving techniques. In general, they are based mainly on the introduction of a third-party mechanism outside the melt extrusion device for the insertion of the reinforcing fibers, which is relatively complex in the forming device.

Disclosure of Invention

In order to overcome the existing problems, a new reinforcing body embedding mode is provided. The invention aims to provide a high-performance fiber-reinforced thermoplastic resin matrix composite material additive manufacturing method, which does not need a mould and a device for independently placing reinforcing fibers, improves the Z-direction combination performance of a formed piece and can realize regional performance regulation and control on the basis of realizing three-dimensional forming of the fiber-reinforced thermoplastic resin matrix composite material, and realizes high-performance manufacturing.

In order to achieve the purpose, the invention adopts the following technical scheme:

a high-performance fiber reinforced thermoplastic resin matrix composite material additive manufacturing method comprises the following steps:

1) carrying out layered dispersion on the three-dimensional data of the target workpiece: performing discrete processing, path planning, process parameter setting and the like on the three-dimensional data of the target workpiece to obtain printing and manufacturing data;

2) preparing a reinforcement body: the reinforcement is a thin rod with certain rigidity and limitation on length and diameter; cutting a wire with a specific diameter into a reinforcement with a certain length; the material of the reinforcement can be three, and is selected according to different functional requirements: preparing unidirectional fiber composite wires with specific diameters, light nonferrous metal wires with specific diameters and fiber metal composite wires with specific diameters such as nickel-plated carbon fibers and copper-plated carbon fibers by a pultrusion process according to the types of resin and fibers of target workpieces; the reinforcement of the fiber reinforced composite material can improve the fiber volume content of the formed part, and the reinforcement of the light nonferrous metal material or the fiber/metal composite material can enable the formed part to have the functions of electric conduction, heat conduction and the like;

3) printing a substrate: starting the inner layer by the double-layer nozzle, and extruding the molten resin-based composite material by the inner-layer nozzle to print the substrate;

4) manufacturing of a target product: the inner layer and the outer layer are started simultaneously by the double-layer nozzle, air is fed into an air inlet of the outer-layer nozzle, airflow is heated into high-temperature heat flow by a heating block above the nozzle, the reinforcement prepared in the step 2) is put in at the moment, and the reinforcement is attached to the resin-based composite material extruded from the inner-layer nozzle at a certain angle along with the high-temperature heat flow; preheating the pre-scanning point by the laser according to the planned path in the step 1), and printing by the spray head according to the planned path and the printing parameters in the step 1); at the intersection of the traces, the reinforcement attached to the extruded material is passively pressed into the resin at the overlap to complete the fabrication of one layer;

5) and (4) repeating the step 4), and in the process of laminating layer by layer, passively pressing the reinforcing bodies attached to the extruded material into the surrounding molten resin until the additive manufacturing of the target product is completed.

Furthermore, the fiber in the fiber reinforced resin matrix composite material is one or more of short fiber, fixed length continuous fiber and continuous fiber, the fiber material is suitable for carbon fiber, aramid fiber, glass fiber and the like, and the resin matrix is suitable for thermoplastic resin such as polylactic acid, polyethylene, nylon (6/66), ABS and the like.

Further, the process parameter settings include, but are not limited to, desired nozzle aperture, scan pitch, scan speed, layer thickness, etc.;

furthermore, the diameter of the prepared reinforcement is 0.05-0.5 mm, the corresponding length is 0.1-1mm, and the size of the reinforcement is related to the diameter of the nozzle; in the printing process, the reinforcements with different specifications can be put in different areas so as to adjust the specifications of the reinforcements in different forming areas of the workpiece, thereby carrying out regional performance regulation and control.

Further, the reinforcement members not only serve as a connection between layers, but also serve as a connection between scanning tracks.

Further, a dual layer nozzle may be substituted for different size models.

Furthermore, the outer layer air inlet of the double-layer nozzle is controllable, including the air inlet speed, the air inlet temperature and the air inlet direction, and the depth and the angle of the reinforcing body attached to the resin matrix composite extruded at the inner layer nozzle in the outer layer nozzle in the step 4) can be controlled.

Furthermore, no space interference exists between the printing head and the laser preheater.

The invention has the following beneficial effects:

1. the invention fuses the fiber reinforced thermoplastic resin matrix composite material additive manufacturing technology based on melt extrusion and the reinforcement embedded reinforcement technology, innovatively uses a double-layer nozzle, the reinforcement is attached and embedded on the melt composite material extruded by the inner-layer nozzle at a certain angle, and the reinforcement is used for multi-directional connection between printed layers and between printed channels, thereby not only improving the interlayer bonding performance, but also enhancing the bonding performance in the XY plane, effectively improving the bonding strength between the layers and between the channels in the melt extrusion forming method, and improving the structural stability and the integrity of a formed piece.

2. According to the performance and functional requirements of different areas of a target product, the invention can use the reinforcements with different specifications in different target areas during printing, thereby realizing the regulation and control of the area performance. The reinforcement prepared by the fiber reinforced composite material can improve the fiber volume content of a formed part, thereby improving the comprehensive mechanical property of the material; the formed piece can have the multiple functions of electric conduction/heat conduction and the like; the same type of reinforcement but different sizes can be used at different layers, and the gradient of functions can be realized.

3. The invention is easy to realize the automation and the digitization of the manufacture of the fiber reinforced thermoplastic resin matrix composite material, and can realize the rapid manufacture of complex large-size composite material components.

Drawings

FIG. 1 is a schematic diagram of an additive manufacturing method of a high-performance fiber-reinforced thermoplastic resin-based composite material.

Reference numerals

1-air inlet and reinforcing body putting port 2-heating block 3-substrate 4-reinforcing body

5-outer layer nozzle 6-inner layer nozzle 7-melt extrusion composite material attached with embedded reinforcement

Detailed Description

For better understanding of the present invention, the following description is further provided in conjunction with the embodiments, but the present invention is not limited to the embodiments below. Furthermore, various changes and modifications may be made by those skilled in the art after reading the disclosure set forth herein, and equivalents may be made thereto without departing from the scope of the invention as defined by the claims appended hereto.

1) Carrying out layered dispersion on the three-dimensional data of the target workpiece: the target part is a cuboid with the length of 50mm, the width of 30mm and the height of 20 mm; discrete processing and path planning are carried out on the product by using commercial software; the print parameters were set as follows: the scanning distance is 1mm, the layer thickness is 0.3mm, the scanning speed is 5mm/s, the temperature is 210 ℃, the printing material is PLA composite continuous carbon fiber material, the diameter of the inner layer nozzle 6 is 0.4mm, and the diameter of the outer layer nozzle 5 is 0.6 mm;

2) preparation of the reinforcement 4: preparing a preparation mode, namely soaking carbon fibers by PLA to prepare a wire material with the diameter of 0.15mm, and cutting the wire material to prepare a reinforcement 4 with the length of 0.3mm and certain rigidity;

3) printing substrate 3: starting the inner layer by the double-layer nozzle, and extruding the molten PLA composite continuous carbon fiber material by the inner layer nozzle 6 to print the substrate 3;

4) manufacturing of a target product: the inner layer and the outer layer are started simultaneously by the double-layer nozzle, air enters from an air inlet 1Z of the outer-layer nozzle 5 at the air speed of 4.5m/s and the temperature of 80 ℃, air flow is heated into high-temperature heat flow by a heating block 2 above the nozzle, the reinforcement body 4 prepared in the step 2) is put in at the moment, and the reinforcement body 4 is attached to the PLA composite continuous carbon fiber material extruded from the inner-layer nozzle 6 at a certain angle along with the high-temperature heat flow; preheating the pre-scanning point by the laser according to the path planned in the step 1), and printing by the nozzle according to the path planned in the step 1) and the printing parameters; when the tracks intersect, the reinforcement 4 attached to the extruded material is passively pressed into the PLA at the overlap, completing the manufacture of one layer;

5) and (4) repeating the step 4), and passively pressing the reinforcing body 4 attached to the extruded material into the molten PLA at the periphery in the process of laminating layer by layer to finish the manufacturing of the target formed piece.