WO2018157841A1

WO2018157841A1 - Additive manufacturing method for interlayer-strengthened continuous fibre composite material

Info

Publication number: WO2018157841A1
Application number: PCT/CN2018/077787
Authority: WO
Inventors: 单忠德; 刘丰; 吴晓川; 李志坤; 张群
Original assignee: 北京机科国创轻量化科学研究院有限公司
Priority date: 2017-03-01
Filing date: 2018-03-01
Publication date: 2018-09-07
Also published as: CN106738891A

Abstract

Disclosed is an additive manufacturing method for an interlayer-strengthened continuous fibre composite material, belonging to the intersecting field of composite materials and additive manufacturing. The steps are: establishing a CAD model for a continuous fibre strengthened composite material product, acquiring ratio data, model profile data and scanning path data about continuous fibres and a substrate of the product, a thread guiding mechanism (1) pulling threads to a print head (2), controlling the print head (2) via CAD drive to perform continuous fibre composite material printing on a workbench (3), laying short fibres between layers through an interlayer auxiliary head (5), using a compaction mechanism (7) to perform compaction of print layers (4), realising additive manufacturing of a continuous fibre strengthened composite material product. The method improves the manufacturing efficiency of continuous fibre strengthened composite material and fibre/resin interface bonding strength, laying short fibres between print layers (4) realises layer-to-layer bonding performance of a composite material product, realising interlayer strengthening of an additive manufactured composite material, improving the material fibre volume fraction, thereby realising high performance, and highly efficient additive manufacturing of continuous fibre strengthened composite material.

Description

Interlayer enhanced continuous fiber composite additive manufacturing method

Technical field

The invention relates to an inter-layer enhanced continuous fiber composite additive manufacturing method, and belongs to the technical field of cross-section of composite materials and additive manufacturing.

Background technique

As a new generation of advanced composite materials, continuous fiber reinforced composite materials have far superior to the specific stiffness and specific strength of metal materials, and also have good thermal stability and design properties, so they are widely used in aerospace vehicles. , high-tech fields such as ships and medical care. The traditional composite material manufacturing technology is mainly composed of two steps of prefabrication manufacturing and substrate infiltration and solidification. In order to achieve good wetting of the matrix, the high strength and high modulus of the continuous fiber reinforced composite parts are effectively improved. The manufacturing process of the composite material is complicated, especially the subsequent molding process of the substrate infiltrating the preform is complicated, and takes a long time and consumes high energy.

The additive manufacturing technology is to form the final part by using the layer-by-layer manufacturing method of raw materials. Compared with the traditional composite material manufacturing technology, the additive manufacturing technology is applied to the manufacture of composite materials, the manufacturing process is simple, and the material utilization rate is high. The curing of the composite material is completed at the same time as the preform is woven, without shortening the manufacturing cycle of the composite material and reducing the manufacturing cost. However, the additive manufacturing method for continuous fiber reinforced composites is not perfect, especially for the development of high performance of composite parts. The existing continuous fiber reinforced composite additive manufacturing method has not solved the problem of low interlayer strength of composite materials. .

The invention provides an interlayer-reinforced continuous fiber composite additive manufacturing method, which improves the bonding performance of the continuous fiber and the substrate by the inter-layer compacting process for pressing the printing material, and on the basis of the interlayer auxiliary mechanism Short fiber placement is carried out between the printing layers, and the fiber reinforced between the layer and the layer is realized by the short fibers laid between the layers, thereby effectively improving the interlayer bonding strength of the composite parts, and also improving the overall The fiber volume fraction of the part, thereby improving the overall performance of the continuous fiber reinforced composite.

Summary of the invention

The invention mainly provides an interlayer-reinforced continuous fiber composite additive manufacturing method, which utilizes a rolling structure to improve the interface bonding property between a continuous fiber and a substrate, and at the same time realizes compounding by laying the interlayer short fibers. The interlayer reinforcement of the material improves the interlayer properties of the composite material while increasing the volume fraction of the material fiber, thereby realizing the high-performance and high-efficiency additive manufacturing of the continuous fiber reinforced composite material.

The invention provides an interlayer-reinforced continuous fiber composite additive manufacturing method, and the specific steps are as follows:

1 Establish a CAD model of continuous fiber reinforced composite parts;

2 obtaining the ratio data, the model contour data and the scan path data of the continuous fiber and the matrix of the workpiece according to the CAD model;

3 selecting a continuous fiber and a base wire suitable for the part to be arranged on the wire guiding mechanism;

4 The selected continuous fiber and the base wire are drawn into the printing nozzle by the wire drawing mechanism, and extruded from the nozzle by melt extrusion;

5 according to the model profile data and the scan path data of the workpiece, the CAD drive is used to control the print head to perform continuous fiber composite printing on the workbench;

6 through the CAD drive to control the interlayer auxiliary nozzle and the printing nozzle to follow, along the scanning path of the workpiece to specify the placement of short fibers;

7 following the driving of the compacting mechanism and the interlayer auxiliary nozzle by the CAD, and compacting the short fiber layer along the scanning path of the workpiece;

8 after completing one layer printing of the workpiece, the workbench is lowered by a certain height;

9 Repeat

steps

5, 6, and 7 to achieve additive manufacturing of the article.

Further, the workbench or the finished print layer is preheated before the printhead performs continuous fiber composite printing.

Further, in the continuous fiber composite printing, the compacting mechanism can be used to compact the printing material in real time along the scanning path.

Further, the continuous fiber and the short fiber are one or more of carbon fiber, aramid fiber, nylon fiber, ceramic fiber, glass fiber, and carbon nanotube fiber.

Further, the wire guiding mechanism can perform fiberizing and preheating of the continuous fibers.

Further, the compacting mechanism can heat the pressure roller.

Further, the print head can perform printing of printing materials and supporting materials.

Further, the laying of the short fibers is carried out by air flow or spiral feeding.

The beneficial effects of the present invention are:

1. The equipment has high automation level and the preparation process is controllable, which can realize the rapid manufacture of large-scale and complex structural parts of continuous fiber reinforced composite materials.

2. By laying short fibers between the printing layer and the layer, the interlayer strength of the bonding interface region can be effectively improved, and the fiber volume fraction of the composite material is increased, thereby realizing high-performance manufacturing of the continuous fiber reinforced composite material.

3. Before the new layer is printed, the auxiliary mechanism is used to preheat the existing printing layer along the scanning path, which not only improves the bonding performance between the printing layer and the layer, but also releases the stress in the printing layer, thereby effectively avoiding the large composite material system. Deformation problems such as warpage of the piece.

DRAWINGS

The accompanying drawings, which are incorporated in the claims of the claims In the drawing:

Figure 1 is a schematic view showing a method of manufacturing an additive according to the present invention;

Figure 2 is a schematic view of the manufacture of continuous fiber reinforced composite parts by additive manufacturing.

Wherein, the above figures include the following reference numerals:

1—Threading mechanism 2—Printing head 3—Working table 4—Printing layer 5—Interlayer auxiliary nozzle 6—Fiber chopped strand 7—Compacting mechanism

detailed description

The specific steps of the method for manufacturing the inter-layer reinforced continuous fiber reinforced composite additive according to the present invention are as follows:

A. Establish a CAD model of continuous fiber reinforced composite parts;

B. Obtaining the ratio data, model contour data and scan path data of the continuous carbon fiber and ABS resin of the workpiece according to the CAD model;

C. Select T300 model 1K carbon fiber and ABS resin wire to be arranged on the wire guiding mechanism;

D. The selected carbon fiber and ABS wire are drawn into the printing nozzle by the wire drawing mechanism, and extruded from the nozzle by melt extrusion;

E. According to the model profile data and the scan path data of the workpiece, the carbon fiber/ABS composite material is printed on the workbench by the CAD drive control printing nozzle;

F. controlling the compacting mechanism and the printing nozzle by the CAD drive, and compacting the printing material along the scanning path of the workpiece;

G. Controlling the interlayer auxiliary nozzle and the printing nozzle by the CAD drive, and performing the carbon fiber chopped strand along the scanning path of the workpiece;

H. The compaction of the chopped carbon fiber layer along the scanning path is carried out by the CAD driving compacting mechanism and the interlayer auxiliary nozzle;

I. After completing one layer printing of the workpiece, the workbench is lowered by a certain height;

J. Repeat step E, step F, step G, and step H to achieve additive manufacturing of the article.

The above-mentioned embodiments are further described in the above description of the present invention, and the scope of the above-mentioned subject matter of the present invention should not be construed as being limited to the above embodiments. The techniques implemented based on the above are all within the scope of the invention.

Claims

An interlayer-reinforced continuous fiber composite additive manufacturing method, characterized in that the specific steps are as follows:

1 Establish a CAD model of continuous fiber reinforced composite parts;

2 obtaining the ratio data, the model contour data and the scan path data of the continuous fiber and the matrix of the workpiece according to the CAD model;

3 selecting a continuous fiber and a base wire suitable for the part to be arranged on the wire guiding mechanism;

4 The selected continuous fiber and the base wire are drawn into the printing nozzle by the wire drawing mechanism, and extruded from the nozzle by melt extrusion;

5 according to the model profile data and the scan path data of the workpiece, the CAD drive is used to control the print head to perform continuous fiber composite printing on the workbench;

6 through the CAD drive to control the interlayer auxiliary nozzle and the printing nozzle to follow, along the scanning path of the workpiece to specify the placement of short fibers;

7 following the driving of the compacting mechanism and the interlayer auxiliary nozzle by the CAD, and compacting the short fiber layer along the scanning path of the workpiece;

8 after completing one layer printing of the workpiece, the workbench is lowered by a certain height;

9 Repeat steps 5, 6, and 7 to achieve additive manufacturing of the article.
The interlayer enhanced continuous fiber composite additive manufacturing method according to claim 1, wherein the workbench or the completed print layer is preheated before the print head performs continuous fiber composite printing.
The interlayer-reinforced continuous fiber composite additive manufacturing method according to claim 1, wherein the continuous fiber composite printing is performed by using a compacting mechanism to perform real-time compaction of the printing material along the scanning path.
The interlayer-reinforced continuous fiber composite additive manufacturing method according to claim 1, wherein the continuous fibers and short fibers are carbon fiber, aramid fiber, nylon fiber, ceramic fiber, glass fiber, carbon nanometer. One or more of the tube fibers.
The interlayer-reinforced continuous fiber composite additive manufacturing method according to claim 1, wherein the yarn guiding mechanism performs fiberizing and preheating of the continuous fibers.
The interlayer-reinforced continuous fiber composite additive manufacturing method according to claim 1, wherein said compacting mechanism heats the pressure roller.
The method of manufacturing an inter-layer reinforced continuous fiber composite additive according to claim 1, wherein said print head performs printing of a printing material and a support material.
The interlayer-reinforced continuous fiber composite additive manufacturing method according to claim 1, wherein the short fibers are laid by air flow or spiral feed.