WO2013181911A1

WO2013181911A1 - Composite material workpiece and shaping method thereof

Info

Publication number: WO2013181911A1
Application number: PCT/CN2012/086777
Authority: WO
Inventors: 单忠德; 杜伟肖; 刘丰
Original assignee: 机械科学研究总院先进制造技术研究中心
Priority date: 2012-06-07
Filing date: 2012-12-17
Publication date: 2013-12-12
Also published as: CN102700147B; CN102700147A

Abstract

The present invention provides a composite material workpiece and a shaping method thereof. For the composite material workpiece, a plurality of support frame pieces is arranged according to the shape of the composite material workpiece. Woven fibers are arranged between the outer surfaces of the support frame piece, so that the woven fibers and the plurality of support frame pieces form a prefabricated piece having a shape matching that of the composite material workpiece. A casting matrix is then dipped into the prefabricated piece and when cured, the composite material workpiece is integrally formed with the prefabricated piece. For the composite material workpiece and the shaping method provided in the present invention, a support frame piece and woven fibers are woven into one integral prefabricated piece having a shape matching that of a composite material workpiece to be processed and dipping formation is performed, so that defects such as inter-layer deformation and misalignment do not occur, the shear strength, compression strength, and bending strength between composite material layers are increased, the integral density of the composite material workpiece is increased, and the rigidity and reliability are further improved, so as to meet the demands of main force bearing structural pieces in aeronautics and astronautics as well as national defense and war industry.

Description

Composite material and forming method thereof

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of composite material forming and molding technology, and in particular to a composite material workpiece. Furthermore, the invention relates to a method of forming a composite article as described above. BACKGROUND OF THE INVENTION Composite parts have excellent performance and are increasingly used in high-end fields such as aerospace, defense, military, medical, and automotive. At present, the common three-dimensional parts of liquid-formed composite materials have various structures, but each has its own shortcomings. In the sandwich structure, the upper and lower panels and the core are joined together by bonding and cementing, so that the entire part can be made lightweight, but a reliable overall structure cannot be formed, and the core and the panel are easily delaminated, and the composite material is reduced. The strength of the piece; the three-dimensional woven composite material woven by weaving, knitting, sewing and other means has good overall performance, but the impregnation effect of the preform with large thickness is poor, and the defects such as impregnation and uneven impregnation often occur; Some of the needles inserted after weaving or laying the laminate are then impregnated with a resin or the like. Such a structure is beneficial for improving the interlaminar shear strength, but the fibers are damaged when the needle is inserted, thereby affecting the entire composite part. performance. On the other hand, in the impregnation process of the conventional liquid forming method, the casting base is gradually infiltrated from the outer surface into the interior of the preform. For composite prefabricated parts with large thickness and shape, defects such as slow penetration, impregnation, uneven impregnation, dry spots and bubbles are often caused, which reduces the density of the entire composite part and affects the strength and performance of the entire part. Can not meet the high quality and high reliability requirements of aerospace, defense and military. Some solutions have been adopted in the prior art. For example, the vacuum introduction process utilizes the flow guiding medium to improve the penetration performance of the preform; the groove is processed on the mold, the external distribution channel of the flow area of the casting substrate is increased, and the casting matrix is promoted. Flow speed, however, the casting matrix such as resin still flows and penetrates from the outer surface of the preform to the inside. It is effective for prefabricated parts with small shell shape and small thickness, but it has little effect on prefabricated parts with large thickness and complicated internal structure. . For example, foam and honeycomb sandwich composites put foam and honeycomb sandwiches into preforms, together with impregnation and solidification, which reduce weight and ease of impregnation for thick preforms, but due to sandwich material and The fiber woven portion of the preform is not a whole, and various defects such as cracking, debonding, weak bonding, layer-to-layer separation, styrofoam voiding, honeycomb core collapse, and loose interface separation are inevitably generated. SUMMARY OF THE INVENTION The object of the present invention is to provide a composite material part and a forming method thereof, so as to solve the technical problem that the existing composite material three-dimensional parts are prone to interlayer misalignment and the composite material parts have low strength. In order to achieve the above object, according to one aspect of the present invention, a composite material member is provided, comprising: a plurality of support frame members arranged according to a shape of a composite material member; a woven fiber woven on an outer surface of the support frame member And forming a preform matching the shape of the composite material together with the supporting frame member; casting the substrate, immersing in the preform and solidifying and integrally forming the composite member with the preform. Further, the support frame member is a support tube. Further, a plurality of flow through holes for circulating the liquid casting base are disposed on the pipe wall of the support pipe. Further, the inner shape and the outer shape of the support tube are adapted to the shape of the composite part. Further, the casting base is one of a resin base, a metal base or a ceramic base. According to another aspect of the present invention, there is also provided a composite material forming method comprising the steps of: arranging a plurality of supporting frame members according to a shape of the composite member; knitting between outer surfaces of the supporting frame members The woven fiber is such that the woven fiber and the supporting frame member together form a preform matching the shape of the composite member; the casting substrate is injected into the preform and the casting substrate is solidified and integrated with the preform to form a composite member. Further, the support frame member is a support tube. Further, before arranging the positions of the plurality of supporting frame members according to the shape of the composite material, the method further includes opening a plurality of through holes for circulating the casting substrate on the side walls of each of the supporting frame members. Further, a liquid molding process is employed when injecting a casting substrate into the preform. The invention has the following beneficial effects: The composite material member and the forming method thereof provided by the invention are jointly woven by the supporting frame member and the woven fiber into a whole preform which is matched with the shape of the composite material piece to be processed and impregnated. Forming, no defects such as interlaminar deformation and misalignment, increased interlaminar shear strength and compressive and flexural strength, improved overall density of composite parts, and improved stiffness and reliability. Adapt to the needs of main bearing structural components such as aerospace and defense military. In addition, the composite material provided by the invention adopts a support tube as a supporting frame member, and a plurality of circulating through holes for circulating the casting base body are arranged on the pipe wall of the supporting pipe, and the casting base body passes through the supporting pipe after passing through the supporting pipe. The flow through hole penetrates from the inside of the support pipe to the outside, impregnates the woven fiber near the support pipe, and thereby diffuses and penetrates into the depth to the outside, so that the preform is integrally impregnated, so that the impregnation of the casting base is hooked, and the bubble and the dry are reduced. Defects such as spots, thereby increasing the overall density and strength of the composite part. In addition to the objects, features and advantages described above, the present invention has other objects, features and advantages. The invention will now be described in further detail with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view showing the internal structure of a composite material according to a preferred embodiment of the present invention; FIG. 2 is a front structural view of a support tube according to a preferred embodiment of the present invention; and FIG. 3 is a preferred embodiment of the present invention. A schematic view of a half-section of the support tube. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention are described in detail below with reference to the accompanying drawings. As shown in FIG. 1, according to an aspect of the present invention, a composite material member is provided, comprising: a plurality of support frame members 10, which are arranged according to the shape of the composite material member; woven fibers 30, Laminated between the outer surfaces of the support frame members 10 and with the support frame members 10 to form a preform matching the shape of the composite member; the casting base 50, immersed in the preform and cured and prefabricated The pieces are integrally formed into a composite part. The composite material member provided by the invention adopts a plurality of supporting frame members 10 as a supporting and forming structure, and then woven fibers 30 are arranged layer by layer on the outer surface of the supporting frame member 10, so that the layers of the composite material members can be interposed. The shear strength is enhanced, which overcomes the defects that the composite parts are easily deformed after impact, and improves the reliability of the composite parts. The support frame member 10 can be a support tube having a hollow structure in the middle. Since the support tube simultaneously serves as a guide for the braiding fibers 30, it can also be referred to as a guide support tube. Further, in order to make composite preforms The impregnation effect is better, and a plurality of flow through holes 11 for circulating the liquid casting base 50 are provided on the pipe wall of each of the support pipes. In the actual weaving process, care should be taken to avoid blocking the flow through hole 11 as much as possible. As shown in FIG. 2 and FIG. 3, the guiding support tube is a hollow structure, and the inner shape and the outer shape of the guiding support tube are adapted to the shape of the composite material piece to be prepared, and can also be said to guide the inner shape and the outer part of the supporting tube. The shape varies depending on the shape and structure of the desired composite part. A through-flow through hole 11 is formed in the pipe wall of the guide support pipe, and the shape of the through-hole 11 is arbitrary. The position and angle of the guiding support tube in the composite part are also different according to the shape and performance requirements of the composite part. The outer shape of the guiding support tube may be a cylindrical tube or a tapered tube, and the inner shape thereof may be It may be tapered or cylindrical, or may be corrugated or the like. The casting base 50 immersed in the preform may be one of a base such as a resin base, a metal base or a ceramic base depending on the performance requirements of the composite material to be manufactured. These materials are known materials, wherein the resin group is also called a polymer base, and the polymer base can be divided into thermosetting polymer bases (such as epoxy resin, unsaturated polyester, polyimide, etc.) and Thermoplastic polymer base (such as various general-purpose plastics and high-performance varieties such as polyether phenol and polyphenylene sulfide). Polymer (resin) The matrix is widely used in composite materials, and its process is mature. Especially, thermosetting polymers have a long history of use, but generally can only be used below 300 °C. Al, Mg, Ti, etc. are commonly used in metal substrates, and superalloys and refractory metals are also in trial use. They are used at temperatures ranging from 400 to 1100 ° C, but the process is not yet mature. A glass base, a ceramic base or the like can also be used as the casting base 50. According to another aspect of the present invention, there is also provided a composite material forming method, the method comprising the steps of: first, arranging a plurality of supporting frame members according to a shape of the composite member; second, supporting The fibers are woven layer by layer between the outer surfaces of the frame members, so that the woven fibers together form a preform matching the shape of the composite member; third, the casting substrate is impregnated into the preform and the casting substrate is solidified with the preform The composite parts are integrally formed. Specifically, the support frame member is a hollow support tube. Before arranging the positions of the plurality of supporting frame members according to the shape of the composite material, the method further includes opening a plurality of through holes for circulating the substrate on the side walls of each of the supporting frame members. A plurality of flow through holes are formed in the pipe wall of the support pipe. The fibers in the vicinity of the support tube are impregnated, and thus diffused outward to the depth to form an integrated inner and outer impregnation. Depending on the shape and strength of the composite part to be manufactured, the size, shape, and number of the through-holes 11 are variable, as long as the strength of the composite part can be satisfied and the impregnation of the casting base 50 can be well achieved. . When the casting substrate is immersed in the preform, a liquid molding process can be used to inject a resin or the like into the preform. The composite material part and the forming method thereof provided by the invention are jointly woven by the support tube and the woven fiber into a whole preform which is matched with the shape of the composite material preform to be processed and impregnated to avoid defects such as force deformation. Increased interlaminar shear strength and compressive and flexural strength of composite materials, improved overall density of composite parts, and improved stiffness and reliability, adapting to main bearing structural components such as aerospace and defense military Demand. In addition, the composite material member and the forming method thereof provided by the invention provide a plurality of flow through holes for circulating the casting base body on the pipe wall of the support pipe, and the porous body is supported by the circulation through holes after the base body is injected into the porous guiding support pipe. The inside of the tube penetrates to the outside, impregnates the fibers in the vicinity of the support tube, and thereby diffuses outward to the outside to form an integrated inner and outer impregnation. The micropores supporting the wall of the tube increase the resin flow channel, promote the resin flow rate, shorten the molding time of the composite material, improve the production efficiency, and at the same time enable the flow of the casting substrate to be hooked, and the fibers deep in the preform can also be the substrate. The impregnation of the hooks avoids the appearance of defects such as impregnation, uneven impregnation, and dry spots, and improves the quality of the impregnation. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A composite material member, comprising: a plurality of support frame members (10) arranged according to a shape of the composite material member;

Woven fibers (30), woven between the outer surfaces of the support frame members (10) and cooperating with the support frame members (10) to form preforms that match the shape of the composite member;

A casting base (50) is immersed in the preform and cured to form the composite article integrally with the preform.

2. A composite article according to claim 1 wherein the support frame member (10) is a support tube.

The composite material part according to claim 1 or 2, wherein a plurality of flow through holes for circulating the liquid casting base body (50) are disposed on the pipe wall of the support pipe. (11).

4. The composite article of claim 3, wherein the inner shape and the outer shape of the support tube are adapted to the shape of the composite article.

The composite article according to claim 3, wherein the casting base (50) is one of a resin base, a metal base or a ceramic base.

A composite material forming method, comprising the steps of:

Locating a plurality of support frame members according to the shape of the composite part;

Woven fibers are woven between the outer surfaces of the support frame members such that the woven fibers and the support frame members together form a preform that matches the shape of the composite member;

A casting base is injected into the preform and the casting matrix is cured to form the composite article integrally with the preform.

The composite material forming method according to claim 6, wherein the supporting frame member is a support tube.

The composite material forming method according to claim 7, further comprising: each of the supporting frame members before the position of the plurality of supporting frame members is arranged according to the shape of the composite material member A plurality of flow through holes for circulating the casting base are formed in the side wall. A method of forming a composite part according to claim 6, 7 or 8, wherein a liquid forming process is employed in injecting a casting base into said preform.