CN114290706A

CN114290706A - Layering method for aerospace composite material grid structure

Info

Publication number: CN114290706A
Application number: CN202111493650.0A
Authority: CN
Inventors: 陈亨津; 荣一鸣; 杨琨
Original assignee: Nanjing Lingrong Material Technology Co ltd; Shanghai Lingrong Mstar Technology Ltd
Current assignee: Nanjing Lingrong Material Technology Co ltd; Shanghai Lingrong Mstar Technology Ltd
Priority date: 2021-12-08
Filing date: 2021-12-08
Publication date: 2022-04-08

Abstract

The invention discloses a continuous void-avoiding laying layer structure of an aerospace composite material grid, taking a 2 x 2 grid laid with three layers as an example, sequentially cutting off four intersections formed by four ribs in a first layer, sequentially cutting off the four intersections in a second layer, and overlapping the three layers of grids, so that every two ribs at the same position in the whole structure can be cut off at the same intersection to form a void-avoiding structure; the problem of traditional shop's layer mode thickness accumulation in the cross point department has effectively been improved to this scheme, has avoided the production of fibre pile up the situation, has effectively reduced the probability of failure.

Description

Layering method for aerospace composite material grid structure

Technical Field

The invention relates to aerospace application of composite materials, in particular to a layering method of an aerospace composite material grid structure.

Background

The composite material grid structure not only inherits the advantages of high specific strength, large specific rigidity, good structural designability and the like of the composite material structure, but also has the advantages of inherent environmental robustness, low cost, high effectiveness and the like, and is highly valued by the aerospace boundary.

There are a variety of methods for manufacturing the lattice structure, including using cross-plied layers of continuous fibers. As shown in fig. 1, this method has a major disadvantage that there is multidirectional fiber accumulation at the intersection of the grid, so that the height at this point is often twice or more than twice that of the non-intersection rib, and if the height is compressed to the same height by force, the fiber content at the intersection is too high, so that the resin is too little to cause poor fiber infiltration, which is a weak point of the structure, and the failure occurs.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to provide a layering method for an aerospace composite grid structure, which meets the use performance requirements and avoids fiber accumulation at cross points.

The technical scheme is as follows: the aerospace composite material grid continuous void-avoiding laying layer structure is characterized in that three layers of 2 x 2 grids are laid, in the first layer, a first transverse rib is cut at the intersection of the first transverse rib and a first longitudinal rib, a second transverse rib is cut at the intersection of the second transverse rib and a second longitudinal rib, the second longitudinal rib is cut at the intersection of the first transverse rib, the first longitudinal rib is cut at the intersection of the second transverse rib, and each cut part is spliced vertically and horizontally;

in the second layer, cutting off the first transverse ribs at the intersections of the first transverse ribs and the second longitudinal ribs, cutting off the second transverse ribs at the intersections of the second transverse ribs and the first longitudinal ribs, and splicing each cut-off part vertically and horizontally;

the grid of the third layer is the same as the grid of the first layer, and then the grids of the three layers are superposed, so that every other layer of the ribs at the same position in the grid can be cut off at the same intersection, and a clearance structure is formed.

Through the technical scheme, the thickness accumulation of the multi-layer grid laying layers at the intersection points can not be formed, and the fiber accumulation is further caused.

Preferably, the splicing gap is less than or equal to 1.5mm, so that the strength of the grid structure can be ensured.

Preferably, a 3 × 3 grid is considered as a combination of 42 × 2 grids, and so on.

Preferably, each rib layer is paved in the same direction and n layers are paved, and then the clearance structure is cut at the same intersection.

Preferably, each rib layer is paved with n layers in the same direction, and then the clearance structure is cut at the same intersection, wherein n is more than 1 and less than 5.

Has the advantages that: compared with the prior art, the invention has the following remarkable advantages: the design of keeping away the sky in the grid structure that adopts in this scheme can be so that avoid the thickness accumulation through the cutting in the coincidence intersection point department of two-layer grid, has improved current grid structure, has avoided the emergence of fibre pile-up situation, has effectively reduced the probability of failure.

Drawings

FIG. 1 is a schematic view of a conventional multi-layer grid structure;

FIG. 2 is a schematic structural view of a three-layer grid according to the present invention;

FIG. 3 is a schematic view of a first layer of the grid of the present invention;

FIG. 4 is a schematic structural diagram of a second layer of grid according to the present invention;

FIG. 5 is a schematic structural view of a third layer of the grid according to the present invention;

FIG. 6 is a schematic view of a first layer of the grid design of the present invention;

FIG. 7 is a schematic view of a second layer of the grid design of the present invention;

FIG. 8 is a schematic plan view of FIG. 3;

fig. 9 is a schematic structural view of a 3 × 3 grid.

Detailed Description

The technical scheme of the invention is further explained by combining the attached drawings.

The laying method of the aerospace composite material grid structure comprises the following steps: for a plurality of ribs in the same direction and a layer of fiber belt, the intersections selected by the laying layer clearance design should be staggered.

As shown in fig. 2, taking a 2 × 2 grid with 3 layers as an example, the number of layers stacked at four intersections is 6, as defined by a conventional continuous layer.

As shown in fig. 3, in the first layer of the 2 × 2 grid, the first transverse ribs 1 are cut and divided into 11 layers and 12 layers at the intersections with the first longitudinal ribs 3; the second transverse ribs 2 are cut and divided into 21 layers and 22 layers at the intersections of the second transverse ribs 4; the first longitudinal ribs 3 are cut and divided into 31 layers and 32 layers at the intersections of the second transverse ribs 2; the second longitudinal ribs 4 are cut at the intersections of the first transverse ribs 1 and divided into 41 layers and 42 layers, each division is spliced vertically and horizontally, and the splicing gap is less than or equal to 1.5 mm. As shown in fig. 6, line 1 is cut by line 3, while line 1 cuts line 4, line 2 cuts line 3, while line 2 cuts line 4.

Fig. 8 is a schematic plan view of fig. 3.

As shown in fig. 4, in the second layer of the 2 × 2 grid, the first transverse ribs 1 are cut at the intersections with the second longitudinal ribs 4 into 13 layers and 14 layers; the second transverse ribs 2 are cut and divided into 23 layers and 24 layers at the intersections of the first longitudinal ribs 3; the first longitudinal ribs 3 are cut and divided into 33 layers and 34 layers at the intersections of the first transverse ribs 1; the second longitudinal ribs 4 are cut at the intersections of the second longitudinal ribs 2 and the second transverse ribs 2 and divided into 43 layers and 44 layers, each division is also spliced longitudinally and transversely, and the splicing gap is less than or equal to 1.5 mm. As shown in fig. 7, line 1 cuts line 3, line 1 is cut by line 4, line 2 is cut by line 3, and line 2 is cut by line 4.

It follows that in the first layer the first transverse ribs 1 are divided by the first longitudinal ribs 3, and that at the same intersection of the second layer the first transverse ribs 3 are not divided, as are the other intersections.

As shown in fig. 5, for a 2 x 2 grid, every other layer of the same position rib is repeatedly cut at a uniform intersection, and so on. Fig. 9 is a schematic structural view of a 3 × 3 grid.

More layers of the cross-grid spacing are possible for numbers above 2 x 2.

Claims

1. A layering method for an aerospace composite material grid structure is characterized by comprising the following steps: laying three layers of 2 x 2 grids, in the first layer, cutting off a first transverse rib (1) at the intersection with a first longitudinal rib (3), cutting off a second transverse rib (2) at the intersection with a second longitudinal rib (4), cutting off the second longitudinal rib (4) at the intersection with the first transverse rib (1), cutting off the first longitudinal rib (3) at the intersection with the second transverse rib (2), and splicing each cut-off part vertically and horizontally;

in the second layer, cutting off the first transverse ribs (1) at the intersections with the second longitudinal ribs (4), cutting off the second transverse ribs (2) at the intersections with the first longitudinal ribs (3), cutting off the second longitudinal ribs (4) at the intersections with the second transverse ribs (2), cutting off the second transverse ribs (2) at the intersections with the first longitudinal ribs (3), and splicing each cut-off part vertically and horizontally;

2. The aerospace composite grid structure layering method of claim 1, wherein a splice gap is no greater than 1.5 mm.

3. A method of laying up an aerospace composite grid structure according to claim 1, wherein a 3 x 3 grid is considered as a combination of 42 x 2 grids and so on.

4. The aerospace composite material grid structure layering method according to claim 1, wherein each rib layering is subjected to void-avoiding structure truncation at the same intersection after n layers are layered in the same direction, and n is more than 1 and less than 5.