CN-116330712-B - Carbon fiber composite T-shaped joint and preparation method thereof

CN116330712BCN 116330712 BCN116330712 BCN 116330712BCN-116330712-B

Abstract

The invention discloses a preparation method of a carbon fiber composite material T-shaped joint, which comprises the steps of respectively paving carbon fiber composite materials on the surfaces of two L-shaped web dies and a skin web die to obtain two L-shaped web preforms and skin web preforms, paving first carbon fiber prepreg tows side by side and adjacent to each other from the vertical section surface of the L-shaped web preforms, reserving backing paper on the first carbon fiber prepreg tows at intervals when the first carbon fiber prepreg tows are paved on the surface of a straight section, attaching the vertical sections of the L-shaped web preforms, forming triangular filling areas, filling the triangular filling areas to obtain a T-shaped structure preform, forming interlocking areas on the T-shaped structure preform, and combining the T-shaped structure preform and the skin web preform by utilizing the interlocking areas to form the carbon fiber composite material T-shaped joint. The method is simple and efficient, and the prepared carbon fiber composite material T-shaped joint has higher interlayer fracture toughness. The invention also provides a carbon fiber composite T-shaped joint.

Inventors

MA JIAHE
XU QIANG
GAO YU
WANG JIAN
ZHANG FAN
LIU YUCHI

Assignees

浙江大学

Dates

Publication Date: 20260508
Application Date: 20230228

Claims (10)

1. The preparation method of the T-shaped joint of the carbon fiber composite material is characterized by comprising the following steps of: (1) Respectively paving carbon fiber composite materials on the surfaces of the two L-shaped web plates to obtain two L-shaped web plate prefabricated bodies, and paving carbon fiber composite materials on the surfaces of the skin web plates to obtain skin web plate prefabricated bodies; (2) The L-shaped web plate prefabricated body sequentially comprises a straight section, a chamfer section and a vertical section, wherein first carbon fiber prepreg tows are paved side by side and adjacently from the surface of the vertical section of the L-shaped web plate prefabricated body, and when the L-shaped web plate prefabricated body is paved on the surface of the straight section, backing paper on the first carbon fiber prepreg tows is kept at intervals, and the backing paper faces the straight section of the L-shaped web plate prefabricated body; (3) Attaching the vertical sections of the two L-shaped web plate prefabricated bodies obtained in the step (2), forming triangular filling areas on the chamfer sections of the two L-shaped web plate prefabricated bodies obtained in the step (2), filling the triangular filling areas with carbon fiber composite materials to obtain a T-shaped structure prefabricated body, and constructing the flat sections of the two L-shaped web plate prefabricated bodies obtained in the step (2) and the flat triangular areas of the two L-shaped web plate prefabricated bodies to form the flat areas of the T-shaped structure prefabricated body; (4) Paving a second carbon fiber prepreg tow on the surface of the flat area to form a first carbon fiber prepreg tow paving area, wherein the first carbon fiber prepreg tow paving area consists of an uncovering area and a paving subarea, and the uncovering area consists of a flat section surface of an L-shaped web preform exposed after the first carbon fiber prepreg tow of the backing paper is uncovered; (5) A third carbon fiber prepreg tow is paved on the surfaces of the uncovering area and the paving subarea to form a second carbon fiber prepreg tow paving area, and in the process of paving the third carbon fiber prepreg tow, the first carbon fiber prepreg tow and the third carbon fiber prepreg tow which remain the backing paper are mutually woven and paved to form a paving interlocking area, wherein the paving angle of the third carbon fiber prepreg tow is different from that of the first carbon fiber prepreg tow; (6) And attaching the skin web prefabricated body to the first carbon fiber prepreg tow laying area and the layering interlocking area to obtain the carbon fiber composite material T-shaped joint.
2. The method for preparing a T-joint made of a carbon fiber composite material according to claim 1, wherein third carbon fiber prepreg tows are laid on the surfaces of the uncovering area and the laying sub-area in a side-by-side and adjacent manner, and the difference between the laying angle of the third carbon fiber prepreg tows and the laying angle of the first carbon fiber prepreg tows is 45 ° -135 °.
3. The method for manufacturing a T-joint for carbon fiber composite material according to claim 1, wherein the second carbon fiber prepreg tow laying area has the same size as the flat area of the T-shaped structural preform.
4. The method for manufacturing the carbon fiber composite material T-shaped joint according to claim 1, wherein a second carbon fiber prepreg tow is paved on the surface of the flat area to form a first carbon fiber prepreg tow paving area, the paving modes are that the first carbon fiber prepreg tows are paved side by side and adjacently, the paving angle of the second carbon fiber prepreg tow is the same as the paving angle of the first carbon fiber prepreg tow on the surface of the flat area, and the paving path of the second carbon fiber prepreg tow overlaps with the paving path of the first carbon fiber prepreg tow on the surface of the flat area.
5. The method of manufacturing a carbon fiber composite T-joint according to claim 1, wherein the first carbon fiber prepreg tow placement region has the same size as the skin web preform surface.
6. The method for preparing the carbon fiber composite T-shaped joint according to claim 1, wherein the specific steps of paving the carbon fiber composite on the surface of the L-shaped web mold or the skin web mold are as follows: And (3) paving carbon fiber prepreg tows side by side and close to the surface of the L-shaped web mold or the skin web mold or directly paving a plurality of layers of carbon fiber prepregs to obtain an L-shaped web preform or a skin web preform.
7. The method for manufacturing a T-joint for carbon fiber composite materials according to claim 1, wherein the backing paper on the surfaces of the vertical sections and the chamfer sections of the two L-shaped web preforms obtained in the step (2) is removed before the vertical sections of the two L-shaped web preforms obtained in the step (2) are aligned and bonded.
8. The method for manufacturing a T-joint made of a carbon fiber composite material according to claim 1, wherein the specific steps of filling the triangular filling area with the carbon fiber composite material are as follows: Filling the triangular filling area through carbon fiber prepreg tows, so that the triangular filling area and the straight sections of the two L-shaped web plate prefabricated bodies form a plane, and then the T-shaped structural prefabricated bodies are obtained.
9. The method of manufacturing a T-joint for carbon fiber composite materials according to claim 1, wherein the first carbon fiber prepreg tows of the remaining backing paper are woven with the third carbon fiber prepreg tows to form a laid interlocking area, and then the backing paper remaining in the first carbon fiber prepreg tows is removed.
10. A carbon fiber composite T-joint, characterized in that it is prepared by the method for preparing a carbon fiber composite T-joint according to any one of claims 1 to 9.

Description

Carbon fiber composite T-shaped joint and preparation method thereof Technical Field The invention belongs to the field of composite material joints, and particularly relates to a carbon fiber composite material T-shaped joint and a preparation method thereof. Background The carbon fiber composite material is formed by converting organic fibers through a series of heat treatments, is an inorganic high-performance fiber with carbon content higher than 90%, is a new material with excellent mechanical properties, has the inherent characteristics of the carbon material, has the soft processability of textile fibers, and is a new generation of reinforcing fiber. Carbon fiber composite materials are widely used in the fields of aerospace, automobile carrying, naval vessels, fan blades and the like because of their excellent specific strength, specific rigidity, specific modulus and fatigue resistance, and represent high-performance engineering materials for structural performance enhancement and structural lightweight design in primary and secondary T-joints for transmitting complex loads between orthogonal structural members. Carbon fiber composite laminates implemented with carbon fiber prepreg placement technology are typical modes of application. However, in actual working conditions, delamination caused by interlaminar shear stress of the carbon fiber composite material laminated plate under the conditions of lateral bending, circumferential torsion and combined load is a main damage mode, and especially, the delamination and debonding of the carbon fiber composite material T-shaped joint at the joint of the components can severely limit the exertion of structural performance. The research on the improvement of the interlayer layering resistance and the T-shaped joint connection performance of the carbon fiber composite material has important significance for guaranteeing the bearing capacity of the material and optimizing the service capacity of the structure. At present, related research at home and abroad has advanced to a certain extent, and the thickness direction reinforcing technology and application of the carbon fiber composite material laminated plate with remarkable improving effect are taken as the main stream development direction. The Chinese patent with publication number CN114683587A discloses a carbon fiber composite T-shaped joint, a manufacturing method and a repairing method thereof, and particularly relates to the technical field of composite joints. The super elasticity of the memory alloy wire enables the damaged component to have certain recovery capability, when repair glue is added for high-temperature repair, the memory of the memory alloy wire enables the component to recover to the shape before stretching, and redundant bonding glue is extruded, and the tensile resistance of the carbon fiber composite material T-shaped joint repaired by the process can be recovered to 80% -90% of that before damage. The above patent meets the requirement of actual repair, shortens the repair period, changes the repair method of component replacement into the repair method of repair, and saves the repair cost. However, the introduction of heterogeneous materials such as glue in the above patents increases the weight of the components and has a certain effect on the connection ability against delamination and debonding. It is therefore desirable to devise a method that can produce carbon fiber composite T-joints with higher interlaminar fracture toughness. Disclosure of Invention The embodiment of the application aims to provide a carbon fiber composite material T-shaped joint and a preparation method thereof. In order to achieve the above object, the technical method adopted in the embodiment of the present application is as follows: in one aspect, an embodiment of the present application provides a method for preparing a T-joint of a carbon fiber composite material, including: (1) Respectively paving carbon fiber composite materials on the surfaces of the two L-shaped web plates to obtain two L-shaped web plate prefabricated bodies, and paving carbon fiber composite materials on the surfaces of the skin web plates to obtain skin web plate prefabricated bodies; (2) The L-shaped web plate prefabricated body sequentially comprises a straight section, a chamfer section and a vertical section, wherein first carbon fiber prepreg tows are paved side by side and adjacently from the surface of the vertical section of the L-shaped web plate prefabricated body, and when the L-shaped web plate prefabricated body is paved on the surface of the straight section, backing paper on the first carbon fiber prepreg tows is kept at intervals, and the backing paper faces the straight section of the L-shaped web plate prefabricated body; (3) Attaching the vertical sections of the two L-shaped web plate prefabricated bodies obtained in the step (2), forming triangular filling areas on the chamfer sections of the two L-s