CN116766624A - Carbon fiber composite material joint structure, preparation method and application thereof - Google Patents

Carbon fiber composite material joint structure, preparation method and application thereof Download PDF

Info

Publication number
CN116766624A
CN116766624A CN202210226198.XA CN202210226198A CN116766624A CN 116766624 A CN116766624 A CN 116766624A CN 202210226198 A CN202210226198 A CN 202210226198A CN 116766624 A CN116766624 A CN 116766624A
Authority
CN
China
Prior art keywords
carbon fiber
layer
composite material
joint structure
fiber composite
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210226198.XA
Other languages
Chinese (zh)
Inventor
谭波
佟金泽
陈立峰
熊海亮
贠莉娜
沈伟
汪娜
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jinggong Shaoxing Composite Technology R & D Co ltd
Shaoxing Baojing Composite Material Co ltd
Original Assignee
Jinggong Shaoxing Composite Technology R & D Co ltd
Shaoxing Baojing Composite Material Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jinggong Shaoxing Composite Technology R & D Co ltd, Shaoxing Baojing Composite Material Co ltd filed Critical Jinggong Shaoxing Composite Technology R & D Co ltd
Priority to CN202210226198.XA priority Critical patent/CN116766624A/en
Publication of CN116766624A publication Critical patent/CN116766624A/en
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
    • B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
    • B29C70/342—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation using isostatic pressure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/48—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor using adhesives, i.e. using supplementary joining material; solvent bonding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00—General aspects of processes or apparatus for joining preformed parts
    • B29C66/70—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material
    • B29C66/74—Joining plastics material to non-plastics material
    • B29C66/742—Joining plastics material to non-plastics material to metals or their alloys
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
    • B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
    • B29C70/345—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation using matched moulds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/54—Component parts, details or accessories; Auxiliary operations, e.g. feeding or storage of prepregs or SMC after impregnation or during ageing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/10—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the pressing technique, e.g. using action of vacuum or fluid pressure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/10—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the pressing technique, e.g. using action of vacuum or fluid pressure
    • B32B37/1018—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the pressing technique, e.g. using action of vacuum or fluid pressure using only vacuum
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B38/00—Ancillary operations in connection with laminating processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/02—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
    • B32B5/24—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer
    • B32B5/26—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer another layer next to it also being fibrous or filamentary
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02K—JET-PROPULSION PLANTS
    • F02K9/00—Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof
    • F02K9/08—Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof using solid propellants
    • F02K9/32—Constructional parts; Details not otherwise provided for
    • F02K9/34—Casings; Combustion chambers; Liners thereof
    • F02K9/343—Joints, connections, seals therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2262/00—Composition or structural features of fibres which form a fibrous or filamentary layer or are present as additives
    • B32B2262/10—Inorganic fibres
    • B32B2262/106—Carbon fibres, e.g. graphite fibres

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Combustion & Propulsion (AREA)
  • General Engineering & Computer Science (AREA)
  • Moulding By Coating Moulds (AREA)

Abstract

The invention discloses a carbon fiber composite material joint structure, which mainly comprises a metal insert and a carbon fiber composite material layer. The metal insert is formed by metal machining, and the small end of the metal insert is provided with a threaded hole for connecting with an external mechanism; the composite material layer is formed by molding carbon fiber prepreg after multi-section synchronous preforming. The preparation process of the composite material joint structure and the application of the joint in solid rocket engine casing are also disclosed. Aiming at the defects of complex structure, long process period, low production efficiency and the like of the composite material joint, the invention greatly shortens the product preforming period and improves the production efficiency by simplifying the structure form, improving the layering mode and optimizing the preforming method on the premise of ensuring the bearing capacity of the product, so that the efficient batch production can be realized.

Description

Carbon fiber composite material joint structure, preparation method and application thereof
Technical Field
The invention relates to the field of space engine shells, in particular to a composite material joint structure, a preparation method and application thereof.
Background
The carbon fiber composite material can effectively lighten the structural quality of the solid rocket engine shell, improve the carrying capacity of effective load, and has important economic and military significance, for example, the third-stage structural quality of a strategic missile solid rocket engine is reduced by 1kg, and the range can be increased by 16km. The joint is a key component in the solid rocket engine shell and plays an important role in external connection and pressure bearing sealing. The traditional metal material joint accounts for about 10-15% of the shell, reduces the weight of the joint, and has important economic and military significance.
Chinese patent CN108332051A, CN 109203510 discloses several carbon fiber composite material joint structures and preparation methods, and the product adopts carbon fiber to replace metal material to obtain weight reduction effect, but all have problems of complex layering structure, long process cycle and the like, so the product has high labor cost and low production efficiency, and is difficult to realize batch production.
Disclosure of Invention
Therefore, the invention aims to solve the technical problems that the layering mode of the composite material joint in production is complex, the process period is long, the production efficiency is low and the like, and provides a carbon fiber composite material structure through the optimal design of the structural form; in addition, the method of making the joint product is provided by improving existing layering and preforming process techniques. The invention also provides application of the carbon fiber composite material joint.
The technical scheme of the invention is that the carbon fiber composite material joint structure comprises a composite material layer and a plurality of metal inserts embedded in the composite material layer;
the composite material layer is in a circular boss shape and is formed by layering, die pressing and curing a plurality of layers of carbon fiber prepregs; the composite material layer structure comprises a surface layer, an outer cladding layer and a paving layer, wherein the surface layer is formed by paving a carbon fiber woven cloth prepreg;
the metal embedded part is embedded in the composite material layer, one end of the metal embedded part is large, the other end of the metal embedded part is small, and a threaded hole is formed in the small end of the metal embedded part. The metal inserts penetrate and are embedded in the composite material layers. The annular boss is in the shape of a composite material layer, one end of the metal embedded piece is large, the other end of the metal embedded piece is small, and threads are arranged at the small end of the metal embedded piece.
According to the carbon fiber composite material joint, preferably, the carbon fibers of the surface layer are carbon fibers with the T300 grade or more; and the carbon fiber T700 grade or more of the outer cladding and the flat-layered carbon fiber is formed.
The composite material layer is formed by performing multi-section synchronous preforming on carbon fiber prepreg and then performing mould pressing and curing.
The surface layer uses carbon fiber woven fabric prepreg to avoid damage to the unidirectional tape at the outer layer of the product caused by subsequent machining, so as to optimize the appearance and performance of the product, and each mechanical property index of carbon fiber contained in the woven fabric prepreg is above T300 level. The outer cladding and the flat paving layer use carbon fiber unidirectional tape prepreg, the paving angles are [ (0 degree/45 degree/90 degree/45 degree/0 degree) s ] n degrees in sequence, and each mechanical property index of the adopted carbon fiber is above T700 grade, wherein the tensile strength is more than 4900MPa, and the tensile modulus is more than 230Gpa.
According to the carbon fiber composite material joint, preferably, the metal insert raw material is selected from high-strength alloy steel 30CrMnSi; the metal insert is conical; the threaded hole is formed in the small end of the cone.
Further, the depth of the threaded hole is about 80-90% of the height of the cone. The depth of the threaded hole is controlled to be 80-90% of the height of the cone body, so that the dead weight of the metal insert can be reduced better.
Further, the side surface of the metal insert is provided with a plane symmetrical to the central axial direction of the cone. Thus, the metal insert can be prevented from axially rotating relative to the composite material layer during bolt assembly and disassembly.
According to the carbon fiber composite joint of the present invention, it is preferable that the thicknesses of the surface layer, the outer cladding layer and the flat layer in the composite layer structure are respectively about: 1-3%, 8-15% and 82-91%.
According to a carbon fiber composite joint of the present invention, it is preferable that the composite layer is provided with an adhesive mounting hole matching the metal insert. And after the composite material layer is solidified and formed, an adhesive mounting hole matched with the metal insert is machined. The specific dimensions and numbers are determined by the product strength and structural design requirements.
The invention also provides a preparation method of the carbon fiber composite material joint structure product, which comprises the following steps:
(1) Tool, die cleaning and assembling: cleaning the surfaces of each block of the flat tool and the curing mold, and completing female mold assembly according to a mold drawing;
(2) And (3) blanking: cutting the carbon fiber prepreg according to the designed layering size;
(3) Multistage synchronous preforming: simultaneously preforming the surface layer, the outer cladding layer and the laid-up layer prepreg in multiple sections by adopting a vacuum bag vacuumizing method, then laying the layers into a female die in sequence, closing the die, and then placing the die on a hot press for further cold pressing preforming; on a flat plate tool, the flat plates are butted and paved layer by layer in a variable cross section increasing layering mode;
(4) Curing: arranging a thermocouple at a glue overflow port of the die, completing a curing process according to a temperature/pressure-time curing curve formulated according to curing characteristics of the used prepreg resin, and releasing pressure and demolding;
(5) And (3) machining: machining mounting holes on the solidified and formed composite material joint according to the size and the number of the metal inserts, and simultaneously completing the production of the metal inserts;
(6) Metal insert mounting: and loading the metal inserts into the composite material joint to obtain a finished product of the composite material joint.
In the step (1), the surface is primarily cleaned by high-pressure air to remove impurities such as dust, resin residues and the like; further wiping clean is then performed using an organic solvent.
The organic solvent is preferably ethyl acetate or acetone; the flat tool is made of metal. Preferably, the flat tooling is made of Q345 steel. The surface of the flat tool is smooth and bright, and the surface is polished until the roughness is less than 3.2 mu m;
in the step (2), according to the shape, angle, sequence and quantity in the process design file, cutting the carbon fiber prepreg used in different layering positions by using an automatic blanking machine;
in the step (3), further, the surface layer and the outer cladding are directly paved on the female die, the outermost layer of the paved area is the surface layer, the thickness of the layer accounts for 1-3% of the total thickness, and the carbon fiber woven fabric prepreg is used.
The outer cladding region is positioned between the surface layer and the flat layer, and blocks crack propagation through fibers perpendicular to the flat layer, so that the whole structure is reinforced, and the limit load is improved. The thickness of the area accounts for 8% -15% of the total thickness, the carbon fiber unidirectional tape prepreg with the grade of T700 is used, and the prepreg sheets are paved layer by layer in a butt joint way according to the design sequence of the process file.
Further, the lay-up is a main component of the composite joint, the thickness of the lay-up accounts for 82% -91% of the total thickness, and the area uses carbon fiber unidirectional tape prepreg with the T700 grade or more. Dividing the material sheets cut according to the process design files into 5-10 parts in sequence, and simultaneously, butt-jointing and paving the material sheets layer by layer on a flat plate tool in a variable cross-section increasing layering mode, wherein the paving angles are [ (0 degree/45 degree/90 degree/45 degree/0 degree) s ] n degrees in sequence. The paving angle can ensure the optimal strength.
In the step (4), a thermocouple is arranged at the position of the female die glue overflow groove and is connected with a temperature measuring instrument to control the temperature of a die, the curing process is completed according to a temperature/pressure-time curing curve formulated according to the curing characteristics of the prepreg resin, and then the pressure is relieved and the die is removed;
in the step (5), the composite material joint body machine comprises cutting and trimming of outer edge spines and burrs and machining of metal insert mounting holes;
the metal insert can be produced by metal processing simultaneously with other steps;
in the step (6), the metal insert can be installed into the composite material joint body by using an adhesive, and a composite material joint finished product is obtained after heating and curing;
when in bonding installation, the front cylinder of the metal insert is subjected to sand blasting treatment. The effective period of the sand blasting is 4 hours, the bonding step is required to be carried out within the effective period of the sand blasting, and if the effective period of the sand blasting is out of date, the sand blasting is required to be carried out again.
According to the preparation method of the carbon fiber composite material joint structure, in the step (1), preferably, the female die and the male die mould pressing surfaces are sprayed with the isolating layers in advance. And spraying an isolating layer, so that the step of coating the release agent is omitted. Further, the isolation layer is a teflon coating.
According to the preparation method of the carbon fiber composite material joint structure, in the step (3), the surface layer and the outer cladding layer are preformed in a female die, and the flat layer is preformed on a smooth flat plate tool, and the surface layer and the outer cladding layer are synchronously developed.
According to the preparation method of the carbon fiber composite material joint structure, in the step (3), the lay-flat layer is divided into 5-10 equal parts, the equal parts are respectively laid on a smooth plane, and vacuum bag is filled for vacuum pre-forming; in the step (3), 3-5 layers of material sheets are paved, a vacuum bag is arranged for preforming, and the duration of each vacuum pumping is 15-30 min.
The spreading layer is divided into 5-10 equal parts, and if the number of the spreading layer is too small, the effect of improving the production efficiency is not obvious; if the number of parts is too large, the required pre-formed bagging area is too large, and interlayer defects are liable to occur due to the fact that the number of parts is too large in the subsequent press-molding lamination.
3-5 layers of material sheets are paved and pasted once, a vacuum bag is punched for preforming, the frequency is too high when the number of layers is too small, the workload is too large, and the efficiency is not obviously improved; too many layers set up and then the evacuation effect is poor, can not reach the preformed purpose.
Further, the surface layer and the outer cladding are preformed directly on the female die, and a vacuum bag is arranged once for each time when 3-5 layers of material sheets are paved, the pressure is smaller than-0.094 MPa, and the duration of each vacuum pumping is not shorter than 15min.
Furthermore, the preforming of the spreading layers is carried out on a flat tool, 3-5 layers of the spreading layers are spread on each part of the material sheet, and a vacuum bag is filled once at the same time, the pressure is-0.2 to-0.094 MPa, and the duration of each vacuumizing is about 15-30 min.
Further, after the vacuum-pumping preforming of the material sheets of the spreading layers is completed, sequentially spreading the material sheets of the spreading layers into a female die and closing the die, and then placing the material sheets of the spreading layers on a hot press for further cold pressing preforming, wherein the pressure is 1.7-2.0 MPa, and the time is about 60-120 min.
The invention also provides application of the carbon fiber composite material joint structure in the technical field of aviation, in particular to application of the carbon fiber composite material joint structure in the aspect of solid rocket engine shells.
The beneficial effects are that:
the invention provides a high-production-efficiency carbon fiber composite material joint structure and a preparation method thereof, aiming at the defects of complex structure of a carbon fiber composite material joint laying layer, long process period and the like, the structure form of the joint is simplified on the premise of ensuring the bearing requirement of a product, and only necessary surface protection, basic structure and auxiliary reinforcing layer are reserved; in addition, in the forming process, the multi-section synchronous preforming method is used for replacing the original layer-by-layer paving preforming, so that the product preforming period is greatly shortened, the production efficiency is improved, and the efficient batch production is realized.
According to the invention, the metal connector of the solid rocket engine shell used in the technical field of aviation is replaced by the carbon fiber composite material, so that the weight of the connector can be reduced by more than 30% due to the composite material of the connector.
Drawings
Fig. 1 is a schematic structural diagram of a carbon fiber composite joint in example 1 provided by the present invention. FIG. 1a is a top view and FIG. 1b is a bottom view;
FIGS. 2 a-2 c are cross-sectional views of metal inserts for carbon fiber composite joints according to the present invention;
FIG. 3 is a schematic diagram of a layering structure in the method for preparing a carbon fiber composite joint according to the present invention;
fig. 4 a-4 c are schematic views of the structure of the surface layer, the outer cladding layer and the lay-up layer of the carbon fiber composite joint according to the present invention.
FIG. 5 is a schematic diagram of a multi-stage synchronous preform in the method for manufacturing a carbon fiber composite joint according to embodiment 1 of the present invention;
in the figure, (1) -composite matrix, (2) -metal insert, (3) -preformed flat tooling.
Detailed Description
Example 1
A carbon fiber composite material joint structure and a preparation method thereof, wherein the shape of a matrix (1) is a flange with an annular boss, the total thickness of the boss is 60mm, the outer diameter of a flange ring is 800mm, the inner diameter is 550mm, and the matrix is composed of carbon fiber composite materials; the joint flange surface is provided with 40 external connecting holes, the joint flange surface is connected with an external mechanism through a metal insert (2) arranged in the joint flange surface, the structure is shown in fig. 2 a-2 c, the metal insert is formed by machining high-strength alloy steel 30CrMnSi, and the specific appearance and the specific dimension are as follows: the appearance is the toper, and tip diameter 18mm, tip diameter 30mm, high 58mm, and the tip is equipped with M10 screw hole, and the hole degree of depth is 47mm, accounts for the high 81% of cone, and cylinder side machine adds the torsional stress plane that is symmetrical in resisting the inserts axial.
The raw materials and the preparation method of the carbon fiber composite material joint structure product are as follows:
raw materials: the prepreg used for the composite joint is produced autonomously by our company and comprises the following components:
the surface layer is woven fabric prepreg with the surface density of 300g/m 2 The carbon fiber is industrial grade carbon fiber with the grade of 3K T300 or more, the weaving direction is vertical weaving, the resin is MT3 type epoxy resin, and the curing temperature is 130-135 ℃; outer cladding and tilingUnidirectional tape prepreg for layer with surface density of 300g/m 2 The carbon fiber is a standard 12K T700 grade industrial grade carbon fiber, the resin is HT2 type epoxy resin, and the curing temperature is 180-185 ℃.
The preparation method comprises the following steps:
(1) Tool, die cleaning and assembling: cleaning the surfaces of the mold blocks and the flat plate tooling for preforming by using a high-pressure air gun and acetone, removing dust, greasy dirt and other impurities, and completing assembly of the female mold according to a drawing after the acetone is completely emitted;
the preformed flat plate tooling is as follows: the material is Q345 steel, and the surface is polished until the roughness is less than 3.2 mu m;
the die conditions are as follows: pre-spraying a Teflon isolation layer on the surface of each block of the die;
(2) And (3) blanking: cutting the carbon fiber prepreg according to the shape, angle, sequence and quantity of each part of the material sheets in the process design file by using an automatic blanking machine;
the overall lay-up of the composite layer is schematically shown in fig. 3, and the skin layer, outer cover and lay-up structures are shown in fig. 4 a-4 c, respectively. The total number of layers of the material sheet is 200, wherein 1 layer and 200 layers are surface layers, 2-19 layers are outer cladding layers, 20-199 layers are flat layers, and the thicknesses of the surface layers, the outer cladding layers and the flat layers are about 1%, 9% and 90% respectively;
(3) Multistage synchronous preforming:
the surface layer and the outer cladding are directly paved on the female die, the outermost layer of the paving area is the surface layer, carbon fiber woven cloth prepreg is used, and the number of the paved layers is 2; and then the outer cladding is prepared by using carbon fiber unidirectional tape prepreg, the number of the layers is 18, and the prepreg sheets are butted and paved layer by layer according to the design sequence of the process file. Applying vacuum bag once every 3 layers of webs, wherein the pressure is about-0.094 MPa, and the duration of each vacuum pumping is 15min;
as shown in fig. 5, the pre-forming of the spreading layers is carried out on a flat plate tool (3), carbon fiber unidirectional tape prepreg is used, the total number of the spreading layers is 180, the cut material sheets are divided into 9 equal parts according to the process design file sequence, 20 layers are arranged on each part, meanwhile, the spreading layers are butted and spread layer by layer on the flat plate tool in a variable cross section progressive spreading mode, the spreading angles are [ (0 degree/45 degree/90 degree/45 degree/0 degree) s ] n DEG, each part of material sheets is spread for 3 layers, a vacuum bag is arranged at the same time, the pressure is about-0.094 MPa, and the duration of each vacuumizing time is 15min;
after the vacuum-pumping preforming of 9 parts of the material sheets of the spreading layer is completed, sequentially spreading the material sheets into a female die and spreading surface layer woven cloth prepreg, putting the material sheets on a hot press for further cold-pressing preforming after die assembly, wherein the pressure is 1.7MPa, and the time is 60min;
(4) Curing: arranging a thermocouple at the position of the glue overflow groove to control the temperature of the die, completing the curing process according to an HT2 epoxy resin curing temperature/pressure-time curing curve, and releasing pressure and demolding;
(5) And (3) machining: machining the composite material joint, arranging a metal insert mounting hole, and finishing the production of the metal insert through the metal machining;
(6) Metal insert mounting: and (3) carrying out sand blasting on the surface of the metal insert cylinder, and after cleaning, installing the metal insert into the composite material joint body by using an adhesive, and heating and curing to obtain a composite material joint finished product.
Example 2
A carbon fiber composite material joint structure and a preparation method thereof are provided, wherein the thickness of an annular boss on a substrate (1) is 126mm, the outer diameter of a flange ring is 1520mm, the inner diameter is 892mm, and the substrate is composed of carbon fiber composite materials; the joint flange surface is provided with 50 external connecting holes, the joint flange surface is connected with an external mechanism through a metal insert (2) arranged in the joint flange surface, the structure is shown in fig. 2 a-2 c, the metal insert is formed by machining high-strength alloy steel 30CrMnSi, and the specific appearance and the specific dimension are as follows: the appearance is the toper, and tip diameter 44mm, and the major end diameter 74mm, high 120mm, and the tip is equipped with M30 screw hole, and the hole degree of depth is 106mm, accounts for cone height 88%, and cylinder side machine adds the torsional stress plane that is symmetrical in resisting the inserts axial.
The preparation method of the carbon fiber composite material joint structure comprises the following steps:
raw materials: as in example 1;
the preparation method comprises the following steps:
(1) Tool, die cleaning and assembling: cleaning the surfaces of the flat tool used for mold segmentation and preforming by using a high-pressure air gun and ethyl acetate respectively, and completing assembly of the female mold according to a drawing after the ethyl acetate is completely developed;
(2) And (3) blanking: cutting the carbon fiber prepreg according to the shape, angle, sequence and quantity of each part of the material sheets in the process design file by using an automatic blanking machine;
the total number of layers of the material sheet is 420 layers, wherein the 1 st layer to the 4 th layer and the 417 th layer to the 420 th layer are surface layers, the 5 th layer to the 64 th layer are outer wrapping layers, the 65 th layer to the 416 th layer are flat paving layers, and the thicknesses of the surface layers, the outer wrapping layers and the flat paving layers are about 1.9%, 14.2% and 83.7% respectively;
(3) Multistage synchronous preforming:
the surface layer and the outer cladding are directly paved on the female die, and the outermost layer of the paved area is the surface layer, and carbon fiber woven fabric prepreg is used; and then the outer cladding is formed, carbon fiber unidirectional tape prepreg is used, and all prepreg sheets are paved layer by layer in a butt joint way according to the design sequence of the process file. Applying a vacuum bag once every 5 layers of tablets, wherein the pressure is about-0.12 MPa, and the duration of each vacuum pumping is 30min;
the flat ply preforming is carried out on a flat tooling (3), carbon fiber unidirectional tape prepreg is used, the total number of plies is 352, the cut material sheets are divided into 8 equal parts according to the process design file sequence, 44 layers are arranged on each part, meanwhile, the flat ply preforming is carried out on the flat tooling in a butt joint mode layer by layer in a variable cross section progressive layering mode, the layering angle is [ (0 degree/45 degree/90 degree/45 degree/0 degree) s ] n DEG, 5 layers are paved on each part of material sheets, a vacuum bag is arranged at the same time, the pressure is about-0.12 MPa, and the vacuumizing duration time is 30min each time;
after the vacuum-pumping preforming of 8 parts of the material sheets of the spreading layer is completed, sequentially spreading the material sheets into a female die and spreading surface layer woven cloth prepreg, putting the material sheets on a hot press for further cold-pressing preforming after die assembly, wherein the pressure is 1.9MPa, and the time is 90min;
the other steps are the same as in example 1.
Aiming at the defects of complex layering structure, long process period and the like of the carbon fiber composite material joint, the invention provides the carbon fiber composite material joint structure with high production efficiency and the preparation method thereof, and the preforming period of the product is greatly shortened and the production efficiency is improved by simplifying the structural form, improving the layering mode and optimizing the preforming method on the premise of ensuring the bearing capacity of the product, so that the efficient batch production of the carbon fiber composite material joint is realized.

Claims (12)

1. The utility model provides a carbon fiber composite material joint structure which characterized in that: the composite material comprises a composite material layer and a plurality of metal inserts embedded in the composite material layer;
the composite material layer is in a circular boss shape and is formed by layering, die pressing and curing a plurality of layers of carbon fiber prepregs; the composite material layer structure comprises a surface layer, an outer cladding layer and a paving layer, wherein the surface layer is formed by paving a carbon fiber woven cloth prepreg;
the metal embedded part is embedded in the composite material layer, one end of the metal embedded part is large, the other end of the metal embedded part is small, and a threaded hole is formed in the small end of the metal embedded part.
2. A carbon fiber composite joint structure according to claim 1, wherein: the carbon fiber of the surface layer is more than T300 grade carbon fiber; and the carbon fiber T700 grade or more of the outer cladding and the flat-layered carbon fiber is formed.
3. A carbon fiber composite joint structure according to claim 1, wherein: the metal insert raw material is selected from high-strength alloy steel 30CrMnSi; the metal insert is tapered.
4. A carbon fiber composite joint structure according to claim 3, wherein: the depth of the threaded hole is about 80-90% of the height of the cone body.
5. A carbon fiber composite joint structure according to claim 3, wherein: the side surface of the metal insert is provided with a plane symmetrical to the central axial direction of the cone.
6. A carbon fiber composite joint structure according to claim 1, wherein: the thicknesses of the surface layer, the outer cladding layer and the paving layer in the composite material layer structure are respectively about: 1 to 3 percent, 8 to 15 percent and 82 to 91 percent.
7. A carbon fiber composite joint structure according to claim 1, wherein: the composite material layer is provided with an adhesion mounting hole matched with the metal insert.
8. The method for preparing the carbon fiber composite joint structure as claimed in claim 1, wherein: the method comprises the following steps:
(1) Tool, die cleaning and assembling: cleaning the surfaces of each block of the flat tool and the curing mold, and completing female mold assembly according to a mold drawing;
(2) And (3) blanking: cutting the carbon fiber prepreg according to the designed layering size;
(3) Multistage synchronous preforming: simultaneously preforming the surface layer, the outer cladding layer and the laid-up layer prepreg in multiple sections by adopting a vacuum bag vacuumizing method, then laying the layers into a female die in sequence, closing the die, and then placing the die on a hot press for further cold pressing preforming; on a flat plate tool, the flat plates are butted and paved layer by layer in a variable cross section increasing layering mode;
(4) Curing: arranging a thermocouple at a glue overflow port of the die, completing a curing process according to a temperature/pressure-time curing curve formulated according to curing characteristics of the used prepreg resin, and releasing pressure and demolding;
(5) And (3) machining: machining mounting holes on the solidified and formed composite material joint according to the size and the number of the metal inserts, and simultaneously completing the production of the metal inserts;
(6) Metal insert mounting: and loading the metal inserts into the composite material joint to obtain a finished product of the composite material joint.
9. The method for manufacturing a carbon fiber composite joint structure according to claim 8, wherein: in the step (1), the mould pressing surfaces of the female mould and the male mould are sprayed with isolation layers in advance.
10. The method for manufacturing a carbon fiber composite joint structure according to claim 8, wherein: in the step (3), the surface layer and the outer cladding layer are preformed in a female die, and the flat layer is preformed on a smooth flat plate tool, and the surface layer and the outer cladding layer are synchronously developed.
11. The method for manufacturing a carbon fiber composite joint structure according to claim 8, wherein: in the step (3), the laying layer is divided into 5-10 equal parts, which are respectively laid on a smooth plane, and simultaneously vacuum bag is arranged for vacuum pre-forming; in the step (3), 3-5 layers of material sheets are paved, a vacuum bag is arranged for preforming, and the duration of each vacuum pumping is 15-30 min.
12. Use of a carbon fiber composite joint structure according to claim 1 in the field of aeronautics, in particular in solid rocket motor cases.
CN202210226198.XA 2022-03-07 2022-03-07 Carbon fiber composite material joint structure, preparation method and application thereof Pending CN116766624A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210226198.XA CN116766624A (en) 2022-03-07 2022-03-07 Carbon fiber composite material joint structure, preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210226198.XA CN116766624A (en) 2022-03-07 2022-03-07 Carbon fiber composite material joint structure, preparation method and application thereof

Publications (1)

Publication Number Publication Date
CN116766624A true CN116766624A (en) 2023-09-19

Family

ID=87988238

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210226198.XA Pending CN116766624A (en) 2022-03-07 2022-03-07 Carbon fiber composite material joint structure, preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN116766624A (en)

Similar Documents

Publication Publication Date Title
US5252160A (en) Method of manufacturing a metal/composite spinner cone
CN102320139B (en) Forming process of curved composite tube
CN108407332B (en) Compression molding method for composite material grid skin structural part
CN110439630B (en) Variable-thickness composite stator blade and forming method thereof
CN108789962B (en) Mould for preparing composite material reinforced structure
CN108995250B (en) RTM forming die of composite material part with segmented rotary structure
US5149251A (en) Metal/composite spinner cone
CN108407333B (en) Composite material mold female die and manufacturing method and application thereof
CN109466088B (en) Mould and compression molding method for fabric prepreg composite material cylinder
CN112644039A (en) Large-opening composite material shell, forming method and forming tool
CN109367071B (en) Production method of fiber reinforced composite ejection push arm
CN112902762B (en) Tail wing stable unshelling armor-piercing bullet holder and preparation method thereof
CN109676958B (en) Co-curing molded carbon fiber composite material airfoil and preparation method thereof
CN113829638B (en) Integrated molding method for composite material cabin section
CN116766624A (en) Carbon fiber composite material joint structure, preparation method and application thereof
CN109304876B (en) RTM (resin transfer molding) method for composite material blade
CN107901448B (en) Large-diameter composite skirt compression curing method
CN116373426A (en) Sandwich structure cover body, preparation method and application thereof
CN215397021U (en) Big open-ended combined material casing and shaping frock
CN108437488A (en) A kind of production method of carbon fibre composite centrifuge rotor
CN112046036B (en) Method for manufacturing composite material ejection support arm
CN111434483A (en) Metal lining braided composite material for vehicle and preparation method and application thereof
CN112297463B (en) Carbon fiber composite piston molding process
CN112123810B (en) Process method for improving forming quality of large-thickness composite material rudder
CN113119490A (en) Integrally-formed composite cabin capable of performing electromagnetic shielding and forming process thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination