CN-121848695-B - Single-thin layer composite material and preparation process thereof

CN121848695BCN 121848695 BCN121848695 BCN 121848695BCN-121848695-B

Abstract

The invention relates to the technical field of composite materials and discloses a single-thin-layer composite material and a preparation process, wherein single-thin-fiber dry yarns are paved on a bottom layer in a preset direction, double-sided adhesive tapes attached to two ends of the single-thin-fiber dry yarns are temporarily fixed on the surface of the bottom layer, release paper is used for covering the exposed surface of the single-thin-fiber dry yarns to finish the pre-fixation of the single-thin-fiber dry yarns, vacuum auxiliary pressure is applied to enable the single-thin-fiber dry yarns to be primarily pressed into and embedded in the bottom layer, then a vacuum bag and release paper are removed to finish the primary embedding of the single-thin-fiber dry yarns, high-temperature-resistant adhesive tapes are used for fixing two ends of the single-fiber dry yarns and removing double-sided adhesives to finish the fixation of the single-thin-fiber dry yarns, the steps are repeated until the designed layering sequence and total thickness are achieved, the laminated layering is completed, the composite material curing process is adopted for curing the laminated layering, and the single-thin-layer composite material is obtained by immersing resin in the fiber prepreg near the single-thin-fiber dry yarns.

Inventors

ZHANG SHUFENG
LIU ZEKUN
Pei Tiangang
CHEN YONGGUI
FAN ZHENGWEI
WANG YASHUN
SHU XINHAO

Assignees

中国人民解放军国防科技大学

Dates

Publication Date: 20260512
Application Date: 20260318

Claims (7)

1. The preparation process of the single-layer composite material is characterized by comprising the following steps of: S100, paving at least one layer of fiber prepreg on a die as a bottom layer; S200, laying the single-thin-fiber dry yarn on a bottom layer according to a preset direction, temporarily fixing the single-thin-fiber dry yarn on the surface of the bottom layer by using double-sided adhesive tapes attached to two ends of the single-thin-fiber dry yarn, and then covering the exposed surface of the single-thin-fiber dry yarn by using release paper to finish the pre-fixing of the single-thin-fiber dry yarn; applying vacuum auxiliary pressure by adopting a prepreg vacuum bag forming method to ensure that the single thin fiber dry yarn is preliminarily pressed into and embedded in the bottom layer, and then removing the vacuum bag and the release paper to finish the preliminary embedding of the single thin fiber dry yarn; Fixing two ends of the dry fiber yarn by using a high-temperature-resistant adhesive tape, and removing double-sided adhesive tape to finish the fixation of the dry single-thin fiber yarn; s300, repeating the steps S100 to S200 until the designed layering sequence and the total thickness are reached, and finishing the layering of the laminated layers; s400, curing the laminated layers by adopting a composite material curing process, wherein resin in the fiber prepreg near the single thin fiber dry yarn is immersed into the single thin fiber dry yarn to form a single thin layer in the curing process, so that the single thin layer composite material is prepared.
2. The process for preparing a single-ply composite according to claim 1, wherein the preparation method of the single-ply fiber dry yarn in step S200 comprises the following steps: S201, applying weights to two ends of the fiber monofilaments, and applying tension to the fiber monofilaments to enable the fiber monofilaments to be in a straightened state; s202, the fiber monofilaments in a straightened state are directionally and parallelly paved on the surface of a fiber dry yarn carrier with double faced adhesive tape, and the paved fiber monofilaments are fixed through the viscosity of the double faced adhesive tape, so that the single-thin fiber dry yarn is prepared.
3. The process for preparing a single-layer composite material according to claim 2, wherein step S201 is specifically: Fiber monofilaments are sequentially paved on two groups of positioning assemblies which are arranged at intervals, positioning grooves which are correspondingly distributed are formed in the two groups of positioning assemblies, and a plurality of positioning grooves are sequentially distributed along the length direction of the positioning assemblies.
4. The process for preparing a single ply composite material according to claim 1, wherein in step S200, the fiber prepreg and the single ply dry yarn are laid up using a multi-angle sequential feeding device comprising: The operation platform is used for sequentially carrying the fiber prepreg and/or the single thin fiber dry yarn and performing layering operation; The support is horizontally arranged on the initial bearing platform in a sliding manner and is used for providing a loading space and horizontally sliding and adjusting along the initial bearing platform; the air pressure sucker is arranged on the bracket in an up-and-down moving way and is arranged towards the direction of the operation platform; the air pressure adjusting tube is communicated to the inner cavity of the air pressure sucker and moves along with the air pressure sucker, and is used for realizing the adsorption and release of the air pressure sucker by utilizing the flow of air; the driving assembly is respectively in driving connection with the support, the air pressure sucking disc and the air pressure regulating pipe and is used for receiving the layering sequence instruction, respectively driving the support to horizontally slide along the initial bearing platform, driving the air pressure sucking disc to move up and down along the support and driving the air pressure regulating pipe to blow or exhaust.
5. The process for preparing a single ply composite material according to claim 4, wherein the fiber prepregs are layered with single ply dry fiber yarns, specifically: sequentially laying the fiber prepreg sheet and the single thin fiber dry yarn to an initial bearing platform according to the arranged laying sequence in a 0-degree direction; Receiving an input layering sequence instruction, wherein the layering sequence instruction comprises angles and sequences of fiber prepregs and single thin fiber dry yarns corresponding to each layering; The moving group horizontally moves on the sliding rail through a moving motor, so that the bracket moves to the position above a layering target of the initial bearing platform; the telescopic motor controls the telescopic column to extend and drives the air pressure sucker to move downwards until the air pressure sucker contacts with the fiber prepreg or the single thin fiber dry yarn; the air pressure adjusting tube sucks air to realize that the air pressure sucker adsorbs fiber prepreg or single thin fiber dry yarn; The telescopic motor controls the telescopic column to shrink and drives the air pressure sucker to move upwards; The rotating motor drives the air pressure sucker to rotate according to the layering sequence instruction, and the fiber prepreg or the single thin fiber dry yarn is rotated to a corresponding angle; The moving group horizontally moves in the sliding rail through a moving motor, so that the bracket moves to the position above the layering operation platform; The telescopic motor controls the telescopic column to extend and drives the air pressure sucker to move downwards until the air pressure sucker contacts with the bottom layer; the air pressure adjusting tube releases air to realize that the air pressure sucker releases fiber prepreg or single thin fiber dry yarn; the telescopic motor controls the telescopic column to retract and drives the air pressure sucker to move upwards; repeating the above process until all the fiber prepregs and the single thin fiber dry yarns are placed on a layering operation platform according to the input instruction.
6. Process for the preparation of a single-ply composite according to any one of claims 1 to 5, characterized in that in step S100 at least one layer of fibrous prepreg is laid down as a bottom layer on a mould, in particular: Paving the continuous unidirectional fiber prepreg or the woven fiber prepreg according to a preset angle; At least one layer of continuous unidirectional fiber prepreg or woven fiber prepreg is laid on the mold as a bottom layer.
7. The process for preparing a single-ply composite according to any one of claims 1 to 5, characterized in that it further comprises, after step S400: s500, cutting the edge of the single-thin-layer composite material, only reserving a core area containing a single thin layer inside, and removing an influence area of an edge process fixing material to obtain the single-thin-layer composite material component.

Description

Single-thin layer composite material and preparation process thereof Technical Field The invention relates to the technical field of composite materials, in particular to a single-thin-layer composite material and a preparation process thereof. Background The continuous fiber reinforced resin matrix composite material has wide application in the fields of aerospace, high-end equipment, sports equipment and the like due to the excellent specific strength and specific rigidity. Conventional composite laminates are typically formed by laminating multiple layers of unidirectional fiber prepregs or braid prepregs and curing them. To impart specific functional or mechanical properties to the composite (e.g., to enhance interlaminar properties, to adjust poisson's ratio, or to introduce functional gradients), it is sometimes desirable to embed thin layers of different orientations or material types in the host layup. However, the prior art has the following problems in achieving embedding of extremely thin functional mats: 1. the thickness of the ply is limited in that the fibers in the conventional prepreg exist in a bundle or aggregation state, and even the thinnest commercial prepreg has the single-layer thickness far greater than the diameters of three fibers, so that the preparation and the introduction of the extremely thin functional ply close to the diameter scale of a single fiber are difficult to realize. 2. The reliability of ply positioning and interface bonding is insufficient, namely if independent ultrathin fiber dry yarns are directly paved on the surface of the prepreg, the independent ultrathin fiber dry yarns are extremely easy to shift, twist and even extrude due to resin flowing or process operation in the subsequent paving and curing processes, and the stability of the design position and orientation of the independent ultrathin fiber dry yarns cannot be ensured, so that the interface bonding quality and the reliability of the final component performance are affected. 3. The existing process method for introducing discrete fibers or special layering into the composite material often depends on complex special equipment or complicated operation steps, is difficult to be effectively compatible with a mature manual paving or automatic prepreg paving process, and restricts the popularization and application of the process in conventional composite material products. Therefore, there is a need in the art for a preparation process that can stably and accurately integrate an oriented single thin layer, having a thickness of a single layer fiber grade, into a conventional continuous fiber composite layer, and that is simple and compatible with existing prepreg molding processes. Disclosure of Invention The invention provides a single-thin-layer composite material and a preparation process thereof, wherein a double-sided adhesive tape is utilized to pre-fix the end part of a single-thin-fiber dry yarn, the single-thin-fiber dry yarn is primarily embedded and fixed in a bottom prepreg by combining vacuum auxiliary pressure, and then the double-sided adhesive tape is replaced by a high-temperature-resistant adhesive tape, so that the single-thin-layer with single-fiber diameter thickness is stably, accurately positioned and reliably combined in the traditional composite material, and the technical problems that in the prior art, extremely thin functional layering is difficult to stably introduce in the continuous fiber composite material, the positioning and interface combination reliability is insufficient and the process compatibility is poor are solved. According to one aspect of the invention, a preparation process of a single-ply composite material is provided, which comprises the following steps of S100, paving at least one layer of fiber prepreg on a die as a bottom layer, S200, paving single-ply dry yarns on the bottom layer according to a preset direction, temporarily fixing the single-ply dry yarns on the surface of the bottom layer by using double-sided adhesive tapes attached to two ends of the single-ply dry yarns, then covering the exposed surface of the single-ply dry yarns by release paper to finish pre-fixing the single-ply dry yarns, applying vacuum auxiliary pressure by adopting a prepreg vacuum bag forming method to enable the single-ply dry yarns to be preliminarily pressed and fixedly embedded on the bottom layer, then removing a vacuum bag and release paper to finish the preliminary embedding of the single-ply dry yarns, fixing the two ends of the single-ply dry yarns by using a high-temperature-resistant adhesive tape to finish the fixing of the single-ply dry yarns, S300, repeating the steps S100 to S200 until the designed laying sequence and total thickness are reached, and finishing the laying of a laminated laying layer by adopting a composite material curing process, curing the single-ply dry yarns near the single-ply wet yarns in the curing process to form the single-ply we