A 3D printing device and method for compounding continuous fiber and granular matrix material

Abstract

The invention discloses a 3D printing device in which continuous fibers and granular matrix materials are compounded, comprising a nozzle, a hopper, a feeding pipe and a screw. The continuous fibers are transported in the middle. The molten matrix material is located around the continuous fibers, and the continuous fibers are surrounded by molten It is impregnated by the base material, which greatly improves the impregnation effect compared with the existing two-way feeding at the nozzle. The present invention also provides a 3D printing method in which continuous fibers and granular matrix materials are composited, which directly utilizes granular or powdery matrix materials for continuous fiber reinforced printing, which solves the limitation of the traditional wire extrusion process on the form and type of printable matrix materials. Problems, expanding the optional range of matrix materials in fiber reinforced printing; at the same time, there is no need to use a wire drawing machine to make the matrix material into a wire before printing, which simplifies the manufacturing process and reduces equipment and operating costs.

Description

technical field [0001] The invention relates to the technical field of 3D printing of continuous fiber reinforced composite materials, in particular to a 3D printing device and method for compounding continuous fiber and particle matrix materials. Background technique [0002] Composite materials refer to materials that combine two or more different substances through various processes. Among them, fiber-reinforced composite materials are the most widely used, that is, fibers are introduced into the matrix material as an additive to improve the performance of the material. In the field of 3D printing, especially the performance advantages of various continuous fibers (carbon fiber, glass fiber, natural fiber, etc.) are used to achieve reinforced polymer materials (polylactic acid, acrylonitrile-butadiene-styrene, epoxy resin, etc.) The purpose of performance, such as obtaining the required characteristics such as light weight, high specific strength, high specific stiffness ...

AI Technical Summary

Problems solved by technology

[0004] However, the currently commonly used 3D printing technology for continuous fiber reinforced composite materials adopts the dipping printing method at the nozzle of the two-way feeding wire, that is, the continuous fiber and the matrix material wire are fed into the nozzle, and the matrix material is melted and impregnated with the fiber under the internal heating of the nozzle, and finally combined with Continuous fiber co-extrusion, this method mainly has the following problems: 1. Because the existing method is to feed the matrix material filament through one side, it will cause the matrix material to be unable to fully and evenly cover the continuous fiber, resulting in easy to appear inside the printed part. The problem of uneven bonding between holes and fibers affects the improvement of its mechanical strength; 2. The existing method is to impregnate the polymer material into the continuous fiber at the nozzle, the impregnation time is short, and the matrix material is difficult to fully penetrate into the fiber bundle Internally, the bonding effect between some single fibers is poor, which affects the mechanical strength of the printed part, and even causes failure; 3. The common method cannot smoothly extrude the high-viscosity molten polymer due to the low extrusion pressure, which makes the fiber reinforced The application of high-viscosity polymers as matrix materials in printing is limited; 4. Since many polymer materials are mostly granular or powdery, and common methods require the use of filamentous materials, that is, the preparation of filaments is indispensable, which not only causes cumbersome processes 1. The manufacturing cost is high, and some polymer materials are difficult or even impossible to prepare filaments that can be used for printing. The limitation of the types of available materials further affects the application range of printed parts

Images