阅读说明：本技术 基于湿法工艺的复合材料盒段结构整体化低成本制造方法 (Wet process based integrated low-cost manufacturing method for composite material box section structure ) 是由 王乾 张业伟 于 2021-09-26 设计创作，主要内容包括：一种基于湿法工艺的复合材料盒段结构整体化低成本制造方法,属于复合材料成型技术领域。该制造方法包括：根据复合材料盒段结构制备成型芯模,将成型芯模连同加强筋作为铺叠膜,将其置于下蒙皮坯料上,采用湿法成型工艺进行复合材料盒段结构上蒙皮坯料的铺叠,合模封装；加热移除成型芯模中的石蜡后,向石蜡对应的异型真空筒袋持续通入压缩气体进行施压,再加热至硬质泡沫塑料热收缩变形,向硬质泡沫塑料对应的异型真空筒袋持续通入压缩气体进行施压,确保合模封装体系内全程负压,固化得到整体化低成本制造的复合材料盒段结构。该制造方法可以在完成新能源通航飞机机翼类复合材料盒段结构整体化成型的基础上,实现该类结构的低成本制造。(A wet process based integrated low-cost manufacturing method for a composite material box section structure belongs to the technical field of composite material forming. The manufacturing method comprises the following steps: preparing a forming core mold according to the composite material box section structure, placing the forming core mold and reinforcing ribs as a laying film on the lower skin blank, laying the skin blank on the composite material box section structure by adopting a wet forming process, and closing the mold for packaging; and after paraffin in the forming core mold is removed by heating, continuously introducing compressed gas into the special-shaped vacuum tube bag corresponding to the paraffin for pressurizing, heating until the rigid foam plastic is subjected to thermal shrinkage deformation, continuously introducing the compressed gas into the special-shaped vacuum tube bag corresponding to the rigid foam plastic for pressurizing, ensuring the whole-process negative pressure in the mold closing and packaging system, and curing to obtain the integrated low-cost manufactured composite material box section structure. The manufacturing method can realize the low-cost manufacturing of the new-energy navigation aircraft wing composite material box section structure on the basis of completing the integrated molding of the structure.)

1. A composite material box section structure integrated low-cost manufacturing method based on a wet process is characterized in that a forming core mold is prepared according to the composite material box section structure, the forming core mold comprises a paraffin wax-special-shaped vacuum barrel bag combined part and a rigid foam plastic-special-shaped vacuum barrel bag combined part, the forming core mold and reinforcing ribs are used as a laying film and are placed on a lower skin blank, the wet process forming process is adopted to lay and package an upper skin blank of the composite material box section structure, and the mold is closed and packaged;

and after paraffin in the forming core mold is removed by heating, continuously introducing compressed gas into the special-shaped vacuum tube bag corresponding to the paraffin for pressurizing, heating until the rigid foam plastic is subjected to thermal shrinkage deformation, continuously introducing the compressed gas into the special-shaped vacuum tube bag corresponding to the rigid foam plastic for pressurizing, ensuring the whole-process negative pressure in the mold closing and packaging system, and curing to obtain the integrated low-cost manufactured composite material box section structure.

2. The integrated low-cost manufacturing method of composite material box section structure based on wet process as claimed in claim 1, wherein said paraffin-shaped vacuum bag assembly is a core mold for manufacturing the region between the front edge end reinforcing rib and the rear edge end reinforcing rib of the composite material box section structure.

3. The integrated low-cost manufacturing method of composite material box section structure based on wet process as claimed in claim 1, wherein said rigid foam plastic-shaped vacuum bag combination portion is a forming core mold portion for manufacturing the region between the reinforcing ribs in the middle of the composite material box section structure.

4. The wet process based integrated low cost manufacturing method of composite box section structure as claimed in claim 1, wherein said rigid foam is of density less than 100kg/m³The high foaming foam of (1).

5. The wet process based integrated low-cost manufacturing method of composite material box section structure according to claim 4, wherein the rigid foam is one of polyethylene foam, polyvinyl chloride foam, polystyrene foam, and polyurethane foam.

6. The integrated low-cost manufacturing method of composite material box section structure based on wet process as claimed in claim 1, wherein the skin blank is fiber cloth impregnated with resin, wherein the gel temperature of resin > thermal shrinkage deformation temperature of rigid foam > melting temperature of paraffin wax.

7. A method for integrally manufacturing a composite material box section structure at low cost based on a wet process is characterized by comprising the following steps:

s1: pouring a paraffin core mould according to the characteristics of areas between reinforcing ribs at the front edge and the front edge end part and between reinforcing ribs at the rear edge and the rear edge end part of the composite material box section structure, correspondingly preparing a first special-shaped vacuum barrel bag, and sleeving the paraffin core mould in the first special-shaped vacuum barrel bag to obtain a paraffin-special-shaped vacuum barrel bag combined part to form a first independent vacuum passage;

s2: processing a rigid foam plastic core mold according to the characteristics of the area between the reinforcing ribs in the middle of the composite material box section structure, correspondingly preparing a second special-shaped vacuum barrel bag, and sleeving the rigid foam plastic core mold in the second special-shaped vacuum barrel bag to obtain a rigid foam plastic-special-shaped vacuum barrel bag combined part to form a second independent vacuum passage;

s3: according to the structural characteristics of the composite material box section structure, taking the paraffin-special-shaped vacuum barrel bag combined part, the rigid foam plastic-special-shaped vacuum barrel bag combined part and the reinforcing ribs as a laying mold;

s4: placing a laying die on the lower skin blank, laying the upper skin blank by adopting a wet forming process, and integrally packaging the uncured composite material box section structure and the die after die assembly to form a third independent vacuum passage;

s5: heating the packaging system, moving out the paraffin core mould after the paraffin core mould is heated to be molten, and continuously introducing compressed gas into the first independent vacuum passage to apply pressure until the composite material box section structure is solidified and molded; after the rigid foam plastic is heated to be subjected to thermal shrinkage deformation, continuously introducing compressed gas into the second independent vacuum passage to apply pressure until the composite material box section structure is cured and molded; and ensuring the negative pressure in the third independent vacuum passage in the whole process in the curing process, dismantling the package and removing the rigid foam plastic subjected to thermal shrinkage deformation to obtain the composite material box section structure.

8. The integrated low-cost manufacturing method of composite material block structure based on wet process as claimed in claim 7, wherein said wet forming process is hand lay-up forming in S4.

9. The integrated low-cost manufacturing method of composite material box section structure based on wet process as claimed in claim 7, wherein the pressure of compressed gas in S5 is 0.1-0.3 MPa.

Technical Field

The invention relates to a wet process-based integrated low-cost manufacturing method for a composite material box section structure, and belongs to the technical field of composite material forming.

Background

The composite material box section structure (as shown in fig. 1) composed of the skin and the reinforcing ribs such as the beam, the wall or the rib is widely applied to the main bearing structure of the aircraft by taking the excellent bearing characteristic of the composite material box section structure as an example of the wing, the skin and the reinforcing ribs are respectively manufactured in the traditional manufacturing mode, and the upper skin, the lower skin and the reinforcing ribs are assembled in a combined mode through secondary bonding or mechanical connection. Due to repeated curing of parts and components caused by secondary bonding and a large amount of machining and assembling work introduced by mechanical connection, the overall manufacturing cost of the composite material part is greatly increased; moreover, the fasteners introduced during the assembly process can be more detrimental to the weight reduction effect of the components. Considering that the manufacturing cost of the composite material mainly comes from the curing cost of parts and the assembly cost of the parts, for a navigation aircraft, particularly a new energy navigation aircraft, the endurance mileage of the aircraft is determined by the weight reduction effect, so that the aim of reducing weight is fulfilled by generally adopting the adhesive joint as an assembly mode, and the whole manufacturing cost of the composite material mainly depends on the curing process of the parts. At present, composite material parts of new energy navigation airplanes are manufactured in a multi-curing component and gluing combined mode, and although a wet forming process mainly based on hand lay-up forming can reduce the manufacturing process cost of prepreg from the material angle on one hand, a glass fiber reinforced plastic tool different from the traditional metal material is adopted on the other hand, the tool manufacturing cost is reduced, the curing times of parts cannot be reduced, the part curing cost is greatly reduced, and therefore the integrated low-cost manufacturing of a composite material box section structure cannot be achieved.

Disclosure of Invention

The invention aims to solve the technical problem of providing a wet process-based integrated low-cost manufacturing method for a composite material box section structure, and the technology can realize low-cost manufacturing of the structure on the basis of completing integrated forming of a new energy navigation aircraft wing composite material box section structure.

The invention discloses a wet process-based integrated low-cost manufacturing method of a composite material box section structure, which comprises the following steps: preparing a forming core mould according to the composite material box section structure, wherein the forming core mould comprises a paraffin wax-special-shaped vacuum barrel bag combined part and a rigid foam plastic-special-shaped vacuum barrel bag combined part, the forming core mould and a reinforcing rib are used as a laying film and are placed on a lower skin blank, the wet forming process is adopted to lay and package the upper skin blank of the composite material box section structure, and the mould is closed and packaged;

and after paraffin in the forming core mold is removed by heating, continuously introducing compressed gas into the special-shaped vacuum tube bag corresponding to the paraffin for pressurizing, heating until the rigid foam plastic is subjected to thermal shrinkage deformation, continuously introducing the compressed gas into the special-shaped vacuum tube bag corresponding to the rigid foam plastic for pressurizing, ensuring the whole-process negative pressure in the mold closing and packaging system, and curing to obtain the integrated low-cost manufactured composite material box section structure.

The paraffin-special-shaped vacuum barrel bag combined part is a forming core mould part for manufacturing areas between reinforcing ribs at the front edge and the front edge end part and between reinforcing ribs at the rear edge and the rear edge end part of a composite material box section structure;

the rigid foam plastic-special-shaped vacuum barrel bag combined part is a forming core mold part for manufacturing the area between the reinforcing ribs in the middle of the composite material box section structure.

The rigid foam plastic has the density of less than 100kg/m³The high foaming plastic of (3) is preferably one of polyethylene foam, polyvinyl chloride foam, polystyrene foam and polyurethane foam.

The skin blank is a fiber cloth impregnated with resin, wherein the gel temperature of the resin is greater than the thermal shrinkage deformation temperature of the rigid foam plastic and the melting temperature of the paraffin.

More specifically: the invention relates to a wet process based integrated low-cost manufacturing method of a composite material box section structure, which comprises the following steps of:

step 1: pouring a paraffin core mould according to the characteristics of areas between reinforcing ribs at the front edge and the front edge end part and between reinforcing ribs at the rear edge and the rear edge end part of the composite material box section structure, correspondingly preparing a first special-shaped vacuum barrel bag, and sleeving the paraffin core mould in the first special-shaped vacuum barrel bag to obtain a paraffin-special-shaped vacuum barrel bag combined part to form a first independent vacuum passage;

step 2: processing a rigid foam plastic core mold according to the characteristics of the area between the reinforcing ribs in the middle of the composite material box section structure, correspondingly preparing a second special-shaped vacuum barrel bag, and sleeving the rigid foam plastic core mold in the second special-shaped vacuum barrel bag to obtain a rigid foam plastic-special-shaped vacuum barrel bag combined part to form a second independent vacuum passage;

and step 3: according to the structural characteristics of the composite material box section structure, taking the paraffin-special-shaped vacuum barrel bag combined part, the rigid foam plastic-special-shaped vacuum barrel bag combined part and the reinforcing ribs as a laying mold;

and 4, step 4: placing a laying die on the lower skin blank, laying the upper skin blank by adopting a wet forming process, and integrally packaging the uncured composite material box section structure and the die after die assembly to form a third independent vacuum passage;

and 5: heating the packaging system, moving out the paraffin core mould after the paraffin core mould is heated to be molten, and continuously introducing compressed gas into the first independent vacuum passage to apply pressure until the composite material box section structure is solidified and molded; after the rigid foam plastic is heated to be subjected to thermal shrinkage deformation, continuously introducing compressed gas into the second independent vacuum passage to apply pressure until the composite material box section structure is cured and molded; and ensuring the negative pressure in the third independent vacuum passage in the whole process in the curing process, dismantling the package and removing the rigid foam plastic subjected to thermal shrinkage deformation to obtain the composite material box section structure.

In the step 4, the wet forming process is preferably a hand lay-up forming process.

The lower skin blank is prepared by a hand lay-up forming process.

In the step 5, the pressure of the compressed gas is 0.1-0.3 MPa.

The invention relates to a low-cost manufacturing method of a composite material box section structure based on a wet process, which is characterized in that a paraffin-special-shaped vacuum barrel bag combined part is adopted to manufacture forming core moulds of areas between reinforcing ribs at the front edge and the front edge end part and between reinforcing ribs at the rear edge and the rear edge end part in the composite material box section structure, and a rigid foam plastic-special-shaped vacuum barrel bag combined part is adopted to manufacture forming core moulds of areas between reinforcing ribs in the middle of the composite material box section structure; meanwhile, the rigid state of paraffin and rigid foam plastic at normal temperature is combined with reinforcing ribs as a stacking die to complete the stacking process of the upper skin blank, and the core die is removed by means of paraffin melting and rigid foam plastic thermal shrinkage characteristics at high temperature, so that the integrated manufacturing process of the composite material box section structure is realized through the subsequent pressurization effect of the special-shaped vacuum barrel bag.

The specific technical scheme of the invention is as follows to solve the technical difficulties:

(1) pouring a paraffin core mould according to the regional characteristics between the reinforcing ribs at the front edge and the front edge end part and between the reinforcing ribs at the rear edge and the rear edge end part, manufacturing a special-shaped vacuum barrel bag, and then placing the paraffin core mould in the vacuum barrel bag to form a first independent vacuum passage to finish the manufacturing of the forming core mould in the region;

(2) processing the rigid foam plastic according to the characteristics of the areas among the reinforcing ribs and manufacturing a special-shaped vacuum barrel bag, after adhering a non-porous isolating film on the surface of the rigid foam plastic, placing the rigid foam plastic into the special-shaped vacuum barrel bag to form a second independent vacuum passage, and finishing the manufacturing of the area forming core mold;

(3) combining the cured net-size reinforcing ribs with the paraffin-special-shaped vacuum barrel bag combined part and the rigid foam plastic-special-shaped vacuum barrel bag combined part, placing the combined parts on a hand-pasted lower skin blank as a laying die, then hand-pasting the formed upper skin blank, closing the die, and packaging the uncured composite material box section structure and the die into a whole to form a third independent vacuum passage;

(4) removing the molten paraffin, introducing compressed gas into a first special-shaped vacuum barrel bag in the paraffin-special-shaped vacuum barrel bag combined part, and continuously pressurizing until the composite material box section structure is solidified and formed;

(5) and after the rigid foam plastic is thermally deformed, continuously heating and simultaneously introducing compressed gas into a second special-shaped vacuum barrel bag in the rigid foam plastic-special-shaped vacuum barrel bag combined part, continuously pressurizing until the composite material box section structure is cured and formed, ensuring the negative pressure in the whole process of closing the mold in the curing process, dismantling the package and removing the rigid foam plastic after shrinkage deformation, and finishing the integral manufacturing of the composite material part with the box section structure.

The integrated low-cost manufacturing method of the composite material box section structure based on the wet process has the beneficial effects that:

the invention selects the recyclable and reusable paraffin and the easily-processed rigid foam plastic with the thermal shrinkage deformation characteristic to prepare the forming core mold, and assists in integrally manufacturing composite material box section structural components such as the wings of the navigation aircraft and the like; moreover, compared with the traditional method, the manufacturing method only increases the material cost and the processing cost of the rigid foam plastic and is far lower than the multiple curing cost involved in the traditional manufacturing method, so that the overall manufacturing cost of the composite material box section structure manufactured by the wet forming process can be obviously reduced.

Drawings

FIG. 1 is a schematic three-dimensional structure of a composite material block structure according to an embodiment of the present invention;

FIG. 2 is a front view of a composite box section structure according to an embodiment of the present invention;

fig. 3 is a schematic structural view of a forming core mold assembly according to an embodiment of the present invention;

FIG. 4 is a schematic view of a first independent vacuum path and a second independent vacuum path in an embodiment of the present invention;

FIG. 5 is a schematic view of a third independent vacuum path in an embodiment of the present invention;

in the above figures, 1 is the leading edge; 2 is the trailing edge; 3 is a front edge end reinforcing rib; 4 is a reinforcing rib at the end part of the rear edge; 5 is a reinforcing rib; 6 is a paraffin core mould; 7 is a first special-shaped vacuum barrel bag; 8 is a rigid foam plastic core mould; 9 is a second special-shaped vacuum barrel bag; 10 is a lower skin; 11 is an upper skin;

a is a first independent vacuum path; b is a second independent vacuum passage; and C is a third independent vacuum passage.

Detailed Description

The present invention will be described in further detail with reference to examples.

The technology discloses a concept that the hard foam plastic and paraffin are combined with the special-shaped vacuum tube bag to use the related material selection, parameter setting, manufacturing process and function, the concept that the rigid foam plastic (or paraffin) -special-shaped vacuum tube bag is adopted to manufacture a forming core mould of each area in a box section structure, the normal temperature characteristics of the paraffin and the hard foam plastic are used as an upper skin blank laying mould, and the concept that the core mould is removed through the high-temperature shrinkage of the hard foam plastic and the melting characteristic of the paraffin is considered to be the protection scope of the invention.

For further illustration but not limitation of the foregoing implementation manner of the present invention, the present invention is further described by taking an integrated low-cost manufacturing method of a typical wet process-based composite box segment structure as an example, where the composite box segment structure prepared in this embodiment is specifically a composite wing, and a schematic structural diagram thereof is shown in fig. 1, and the detailed manufacturing method relates to the following contents:

1) heating the crude paraffin to more than 60 ℃ for complete melting, pouring a paraffin core mould 6 and manufacturing a corresponding first special-shaped vacuum barrel bag 7 according to the configuration characteristics of areas between a front edge 1 and a front edge end reinforcing rib 3 and between a rear edge 2 and a rear edge end reinforcing rib 4 in the wing structure, placing the paraffin core mould 6 in the first special-shaped vacuum barrel bag 7 and connecting the paraffin core mould 6 in parallel to form a first independent vacuum passage A, and obtaining a paraffin-special-shaped vacuum barrel bag combined part, wherein the schematic diagram of the paraffin-special-shaped vacuum barrel bag combined part is shown in fig. 3 and 4.

2) Selecting rigid polystyrene foam, processing a rigid foam core mould 8 and manufacturing a corresponding second special-shaped vacuum barrel bag 9 according to the configuration characteristics of the area between the reinforcing ribs in the wing structure, sticking a layer of non-porous isolating film on the surface of the rigid foam core mould 8, placing the rigid foam core mould into the second special-shaped vacuum barrel bag 9, connecting the rigid foam core mould and the second special-shaped vacuum barrel bag in parallel to form a second independent vacuum passage B, and obtaining a rigid foam-special-shaped vacuum barrel bag combined part, wherein schematic diagrams of the rigid foam-special-shaped vacuum barrel bag combined part are shown in fig. 3 and 4.

3) After hand lay-up forming of a blank of a lower skin 10, combining a cured net-size reinforcing rib with the paraffin-special-shaped vacuum barrel bag combined part in the step 1) and the rigid foam-special-shaped vacuum barrel bag combined part in the step 2) to serve as a laying die to be positioned at the corresponding position of the lower skin, hand lay-up forming of a blank of an upper skin 11 on the upper surface of the lower skin, and then die assembly, wherein the schematic diagram is shown in the figure 2, an uncured wing and a die are packaged into a whole and provided with a third independent vacuum passage C, the schematic diagram is shown in the figure 5, and vacuum pressure of the third independent vacuum passage C in the whole course of curing is ensured. Wherein the gel temperature of the resin selected from the upper and lower skin blanks is greater than the thermal deformation temperature of the rigid foam plastic and the melting temperature of paraffin;

4) when the temperature rises to 60-70 ℃, the molten paraffin is removed, then 0.3MPa of compressed gas is introduced into the first independent vacuum passage A, and the pressure is continuously increased until the composite material wing is solidified and molded.

5) When the temperature rises to 80-90 ℃, continuously increasing the temperature, simultaneously introducing 0.3MPa of compressed gas into the second independent vacuum passage B, continuously pressurizing until the composite material wing is cured and molded, dismantling the package, and removing the rigid foam plastic after shrinkage deformation to complete the integrated manufacturing of the composite material wing.

Comparative example

The upper skin and the lower skin and the reinforcing ribs are respectively cured by the traditional manufacturing method, and the curing times are 3; the invention only comprises the processes of reinforcing rib curing and box section structure integral curing, and the curing times are 2 times. Considering that the conventional manufacturing method increases the curing cost and the process auxiliary material cost, the invention relates to the use of paraffin wax and rigid foam, but the paraffin wax is about 10 yuan/kg (and can be recycled) and the rigid foam is 600 yuan/m³The use price of the polyethylene foam plastic is far lower than the process auxiliary material cost additionally increased by the traditional manufacturing method. Therefore, the invention saves at least 1 time of curing cost compared with the traditional manufacturing method, and has the characteristic of low-cost manufacturing on the basis of meeting the requirement of integrally manufacturing the composite material box section structure.