Aerospace Composite Material Mould Thin Shell Surface Hot Pressing Forming Tooling and Manufacturing Method

Abstract

The present invention relates to a hot pressing forming tooling for the thin shell surface of an aviation composite material mold and a manufacturing method. For the disadvantages of poor accuracy of the thin shell surface of the mold with large surface size and deep cavity, easy deformation during heating, high cost, etc., in order to overcome these deficiencies, the present invention provides a hot pressing forming tooling for the thin shell surface of an aviation composite material mold and a manufacturing method, which mainly consists of an upper die assembly, a lower die assembly, a thin shell surface, a positioning pin assembly, etc. A three-dimensional digital model of the thin shell surface of the mold is established, and the upper die assembly and the lower die assembly with a grid structure welded by template are adopted according to the digital model, which are composed of two identical thin shell surfaces one and two and two thin shell reference plates. The blank of the thin shell surface one or the thin shell surface two is heated to 750 - 800 °C and moved onto the hot pressing lower die assembly and positioned by the positioning pin assembly, and then stamped by the hot pressing upper die assembly. After shaping, the thin shell surface one and the thin shell surface two are welded into a thin shell surface, and then subjected to numerical control precision machining and airtightness test.

Description

Technical Field

[0001] The present invention relates to a hot pressing forming tooling for the thin shell surface of an aviation composite material mold and a manufacturing method thereof. Background Art

[0002] Composite materials are widely used in the fields of aviation, aerospace, automotive, medical, etc. For aviation composite material parts with large surface dimensions and deep cavities, the hot pressing forming molds for manufacturing aviation composite material parts are large in volume, heavy in weight, and difficult to move. Generally, frame-type molds are used in the hot pressing forming of composite material parts. However, in this process method, the hot pressing plate will produce elastic deformation. During the processes of primary processing such as punching and shearing separation of the sheet blank to form parts and welding and assembling into a shape, as well as during production and transportation, various elastic deformations may occur. The occurrence of such deformations affects the surface accuracy of the hot pressing forming mold and the composite material product, and may even cause the composite material product to be scrapped. If the elastic deformation of the thin shell surface of the hot pressing forming mold used in the manufacturing of aviation composite materials can be reduced, the cost can be reduced and the accuracy of aviation composite material parts can be improved. To overcome these deficiencies, the present invention designs a hot pressing forming tooling for the thin shell surface of an aviation composite material mold and a manufacturing method thereof, which is used to manufacture the thin shell surface of the mold and is suitable for a thin shell surface with a length less than 2000 mm and a cavity depth of 850 - 1300 mm. Summary of the Invention

[0003] The technical problems to be solved by the present invention are that there are generally two processing methods for manufacturing the hot pressing forming tooling for the thin shell surface of an aviation composite material mold: The first method is to use conventional steel blocks for numerical control integral processing, which wastes materials and has a long processing time, and it is more difficult to process a cavity with a large depth and a small width. Generally, this method is not used for the thin shell surface of medium and large-sized molds; the second method is to use a hot pressing plate, which can save materials, and the cavity depth can be larger and the cavity width can be smaller. Generally, this method is used for the thin shell surface of medium and large-sized molds. However, in this process method, the hot pressing plate will produce elastic deformation. During the processes of primary processing such as punching and shearing separation of the sheet blank to form parts and welding and assembling into a shape, as well as during production and transportation, various deformations may occur. The occurrence of such deformations affects the surface accuracy of the mold thin shell surface and the composite material product, and may even cause the composite material product to be scrapped. To improve the surface accuracy of the mold thin shell surface, reduce the influence of elastic deformation on the mold thin shell surface, reduce the waste of scrap caused by elastic deformation, and further reduce the cost to a greater extent, it is particularly necessary to design a hot pressing forming auxiliary tooling for manufacturing the mold thin shell surface. To overcome these deficiencies, the present invention relates to a hot pressing forming tooling for the thin shell surface of an aviation composite material mold and a manufacturing method thereof. The hot pressing forming tooling for the thin shell surface of an aviation composite material mold is composed of a hot pressing upper die assembly, a hot pressing lower die assembly, a thin shell surface, a positioning pin assembly, etc.

[0004] The object of the present invention is to provide a hot pressing forming tooling for the thin shell surface of an aviation composite material mold and a manufacturing method. The hot pressing upper die assembly and the hot pressing lower die assembly are welded into a grid-shaped frame structure by frame insertion and splicing. The characteristic of this structure is that the welding deformation is small and the structure is stable. The openings on the jig can not only achieve structural stability, but also ensure uniform heating under the hot pressing working state, meeting the favorable conditions for hot pressing composite material forming. The present invention can also meet the forming of composite material products with deeper cavities. The thin shell surface of the hot pressing forming mold has small elastic rebound deformation. At the same time, the hot pressing forming tooling saves materials, reduces costs and significantly shortens the manufacturing cycle.

[0005] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0006] The hot pressing forming tooling for the thin shell surface of an aviation composite material mold is composed of a hot pressing upper die assembly (1), a hot pressing lower die assembly (2), a thin shell surface (3), and a positioning pin assembly (4). It is characterized in that: the hot pressing upper die assembly (1), the hot pressing lower die assembly (2) and the positioning pin assembly (4) form a hot pressing forming tooling, and the thin shell surface (3) of the aviation composite material mold is manufactured by hot pressing forming.

[0007] The hot pressing upper die assembly (1) is composed of 27 types of template plates, made of ordinary steel plates with a thickness of 7 - 8 mm, and are connected by slot insertion, snap connection with a slot and welding rigid connection methods to form a grid-shaped frame structure. The hot pressing upper die assembly (1) is composed of a rear template plate of the upper die (1-1), a first left template plate of the upper die (1-2), a first front template plate of the upper die (1-3), a second front template plate of the upper die (1-4), a third front template plate of the upper die (1-5), a first right template plate of the upper die (1-6), a first middle horizontal template plate of the upper die (1-7), a second middle horizontal template plate of the upper die (1-8), a third middle horizontal template plate of the upper die (1-9), a fourth middle horizontal template plate of the upper die (1-10), a first middle vertical template plate of the upper die (1-11), a second middle vertical template plate of the upper die (1-12), a third middle vertical template plate of the upper die (1-13), a fourth middle vertical template plate of the upper die (1-14), a fifth middle vertical template plate of the upper die (1-15), a sixth middle vertical template plate of the upper die (1-16), a seventh middle vertical template plate of the upper die (1-17), a first characteristic curved surface template plate of the upper die (1-18), a second characteristic curved surface template plate of the upper die (1-19), a third characteristic curved surface template plate of the upper die (1-20), a fourth characteristic curved surface template plate of the upper die (1-21), a fifth characteristic curved surface template plate of the upper die (1-22), a sixth characteristic curved surface template plate of the upper die (1-23), a seventh characteristic curved surface template plate of the upper die (1-24), an eighth characteristic curved surface template plate of the upper die (1-25), a ninth characteristic curved surface template plate of the upper die (1-26), and a tenth characteristic curved surface template plate of the upper die (1-27). The 27 types of template plates are rigidly connected into a grid-shaped frame structure through slot insertion, snap connection with a slot. The grid interval dimension is 200 - 300 m, and the specific number of grids and interval dimension are determined by the composite material product parts and the thin shell surface (3).

[0008] The upper die rear template (1-1), the upper die left template one (1-2), the upper die front template one (1-3), the upper die front template two (1-4), the upper die front template three (1-5), and the upper die right template one (1-6) are rigidly connected by welding to form the outer frame of the hot pressing upper die assembly (1); the upper die rear template (1-1) is rigidly connected to the upper die middle longitudinal template one (1-11), the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template six (1-16), and the upper die middle longitudinal template seven (1-17) by the template slot hole one (1-1-3) and the template buckle two (1-11-4); the upper die rear template (1-1) is rigidly connected to the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template three (1-13), and the upper die middle longitudinal template four (1-14) by the template slot hole one (1-1-3) and the template buckle three (1-12-4); the upper die front template two (1-4) is rigidly connected to the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template three (1-13), and the upper die middle longitudinal template four (1-14) by the template slot hole three (1-4-3) and the template buckle three (1-12-4); the upper die middle transverse template one (1-7), the upper die middle transverse template two (1-8), and the upper die middle transverse template three (1-9) are respectively rigidly connected to the upper die left template one (1-2) and the upper die right template one (1-6) by the template buckle one (1-7-4) and the template slot hole two (1-2-3); the upper die middle longitudinal template one (1-11), the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template three (1-13), the upper die middle longitudinal template four (1-14), the upper die middle longitudinal template five (1-15), the upper die middle longitudinal template six (1-16), and the upper die middle longitudinal template seven (1-17) are respectively connected by plugging with the template slot two (1-11-3) and the template slot one (1-7-3) between the upper die middle transverse template one (1-7), the upper die middle transverse template two (1-8), and the upper die middle transverse template three (1-9), and the plugging assembly gap is 0.8 - 1.8 mm; the upper die middle transverse template four (1-10) is connected by plugging with the upper die middle longitudinal template one (1-11), the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template three (1-13), the upper die middle longitudinal template four (1-14), the upper die middle longitudinal template five (1-15), the upper die middle longitudinal template six (1-16), and the upper die middle longitudinal template seven (1-17) by the template slot six (1-10-3) and the template slot one (1-7-3), and the plugging assembly gap is 0.8 - 1.8 mm; the upper die feature surface template 1 (1-18), upper die feature surface template 2 (1-19), upper die feature surface template 3 (1-20), upper die feature surface template 4 (1-21), upper die feature surface template 5 (1-22), upper die feature surface template 6 (1-23), upper die feature surface template 7 (1-24), upper die feature surface template 8 (1-25), upper die feature surface template 9 (1-26), and upper die feature surface template 10 (1-27) are feature surface templates, which are arranged at intervals between the upper die right template 1 (1-6), upper die middle horizontal template 4 (1-10), upper die middle vertical template 1 (1-11), upper die middle vertical template 2 (1-12), upper die middle vertical template 3 (1-13), upper die middle vertical template 4 (1-14), upper die middle vertical template 5 (1-15), upper die middle vertical template 6 (1-16), upper die middle vertical template 7 (1-17), and upper die left template 1 (1-2), and are rigidly connected by welding to form a space grid framework. At the places where the curvature of the thin shell surface changes greatly, the number of feature surface types is increased, so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce the more maintenance and correction caused by the elastic deformation of the thin shell surface in the later stage.

[0009] The upper die rear template (1-1) is composed of a first base body (1-1-1), a first mold surface (1-1-2), seven template slot holes one (1-1-3), and two template holes one (1-1-4). The outer shape of the first base body (1-1-1) is processed by a wire cutting device. The digital model of the first mold surface (1-1-2) is consistent with the thin shell mold surface (3). The spacing dimension of the template slot holes one (1-1-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell mold surface (3). The left upper die template one (1-2) and the right upper die template one (1-6) have the same structure. The left upper die template one (1-2) is used to represent and illustrate the composition of the two template structures. The left upper die template one (1-2) is composed of a second base body (1-2-1), a second mold surface (1-2-2), three template slot holes two (1-2-3), and two template holes two (1-2-4). The outer shape of the second base body (1-2-1) is processed by a wire cutting device. The digital model of the second mold surface (1-2-2) is consistent with the thin shell mold surface (3). The spacing dimension of the template slot holes two (1-1-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell mold surface (3). The front upper die template one (1-3) and the front upper die template three (1-5) have the same structure. Taking the front upper die template one (1-3) as an example, it illustrates the composition of the two template structures. The front upper die template one (1-3) is composed of a third base body (1-3-1), a third mold surface (1-3-2), and a template hole three (1-3-3). The outer shape of the third base body (1-3-1) is processed by a wire cutting device. The digital model of the third mold surface (1-3-2) is consistent with the thin shell mold surface (3). The front upper die template two (1-4) is composed of a fourth base body (1-4-1), a fourth mold surface (1-4-2), and a template slot hole three (1-4-3). The outer shape of the fourth base body (1-4-1) is processed by a wire cutting device. The digital model of the fourth mold surface (1-4-2) is consistent with the thin shell mold surface (3). The spacing dimension of the template slot hole three (1-4-3) is 200 - 300 mm and is the same as the spacing of the slot holes of the upper die rear template (1-1). The upper die middle horizontal template one (1-7), the upper die middle horizontal template two (1-8), and the upper die middle horizontal template three (1-9) have the same structure. Taking the upper die middle horizontal template one (1-7) as an example, it illustrates the composition of these three template structures. The upper die middle horizontal template one (1-7) is composed of a seventh base body (1-7-1), a seventh mold surface (1-7-2), seven template slots one (1-7-3), and two template buckles one (1-7-4). The outer shape of the seventh base body (1-7-1) is processed by a wire cutting device. The digital model of the seventh mold surface (1-7-2) is consistent with the thin shell mold surface (3). The spacing dimension of the template slots one (1-7-3) is 200 - 300 mm and is the same as the spacing of the slot holes of the upper die rear template (1-1).The upper die middle horizontal template four (1 - 10) consists of a matrix five (1 - 10 - 1), a profile five (1 - 10 - 2), and seven template slots six (1 - 10 - 3). The outer shape of the matrix five (1 - 10 - 1) is processed by a wire - cutting device. The digital model of the profile five (1 - 10 - 2) is consistent with the thin - shell profile (3). The spacing dimension of the template slots six (1 - 10 - 3) is 200 - 300 mm, which is consistent with the spacing of the slot holes of the upper die rear template (1 - 1). The upper die middle vertical template one (1 - 11), the upper die middle vertical template two (1 - 12), the upper die middle vertical template six (1 - 16), and the upper die middle vertical template seven (1 - 17) have the same structural composition. Taking the upper die middle vertical template one (1 - 11) as an example, the structural composition of these four templates is described. The upper die middle vertical template one (1 - 11) consists of a matrix eight (1 - 11 - 1), a profile eight (1 - 11 - 2), three template slots two (1 - 11 - 3), and a template buckle two (1 - 11 - 4). The outer shape of the matrix eight (1 - 11 - 1) is processed by a wire - cutting device. The digital model of the profile eight (1 - 11 - 2) is consistent with the thin - shell profile (3). The spacing dimension of the template slots two (1 - 11 - 3) is 200 - 300 mm, which is consistent with the spacing of the slot holes of the upper die left template one (1 - 2). The upper die middle vertical template three (1 - 13), the upper die middle vertical template four (1 - 14), and the upper die middle vertical template five (1 - 15) have the same structural composition. Taking the upper die middle vertical template three (1 - 13) as an example, the structural composition of these three templates is described. The upper die middle vertical template two (1 - 13) consists of a matrix nine (1 - 13 - 1), a profile nine (1 - 13 - 2), three template slots three (1 - 13 - 3), and two template buckles three (1 - 13 - 4). The outer shape of the matrix nine (1 - 13 - 1) is processed by a wire - cutting device. The digital model of the profile nine (1 - 13 - 2) is consistent with the thin - shell profile (3). The spacing dimension of the template slots three (1 - 13 - 3) is 200 - 300 mm, which is consistent with the spacing of the slot holes of the upper die left template one (1 - 2). The upper die characteristic - surface templates one (1 - 18) to ten (1 - 27) have the same structural composition. Taking the upper die characteristic - surface template one (1 - 18) as an example, the structural composition of these 10 characteristic - surface templates is described. The upper die characteristic - surface template one (1 - 18) consists of a matrix ten (1 - 18 - 1) and a profile ten (1 - 18 - 2). The outer shape of the matrix ten (1 - 18 - 1) is processed by a wire - cutting device. The digital model of the profile ten (1 - 18 - 2) is consistent with the thin - shell profile (3).;

[0010] The hot pressing lower die assembly (2) is composed of 26 types of template plates, which are made of ordinary steel plates with a thickness of 7 - 8 mm. They are connected to form a grid - type frame structure by means of slot insertion, snap - and - slot connection and welding rigid connection. The hot pressing lower die assembly (2) consists of a rear lower die template plate (2 - 1), a left lower die template plate 1 (2 - 2), a front lower die template plate 1 (2 - 3), a front lower die template plate 2 (2 - 4), a front lower die template plate 3 (2 - 5), a right lower die template plate 1 (2 - 6), a middle horizontal lower die template plate 1 (2 - 7), a middle horizontal lower die template plate 2 (2 - 8), a middle horizontal lower die template plate 3 (2 - 9), a middle horizontal lower die template plate 4 (2 - 10), a middle vertical lower die template plate 1 (2 - 11), a middle vertical lower die template plate 2 (2 - 12), a middle vertical lower die template plate 3 (2 - 13), a middle vertical lower die template plate 4 (2 - 14), a middle vertical lower die template plate 5 (2 - 15), a middle vertical lower die template plate 6 (2 - 16), a middle vertical lower die template plate 7 (2 - 17), a lower die characteristic curved surface template plate 1 (2 - 18), a lower die characteristic curved surface template plate 2 (2 - 19), a lower die characteristic curved surface template plate 3 (2 - 20), a lower die characteristic curved surface template plate 4 (2 - 21), a lower die characteristic curved surface template plate 5 (2 - 22), a lower die characteristic curved surface template plate 6 (2 - 23), a lower die characteristic curved surface template plate 7 (2 - 24), a lower die characteristic curved surface template plate 8 (2 - 25), a lower die characteristic curved surface template plate 9 (2 - 26). The 26 types of template plates are rigidly connected to form an equally - spaced grid - type frame structure through slot insertion, snap - and - slot rigid connection. The grid interval size is 200 - 300 mm, and the specific number of grids and interval size are determined by the composite material product parts and the thin - shell surface (3). The rear lower die template plate (2 - 1), the left lower die template plate 1 (2 - 2), the front lower die template plate 1 (2 - 3), the front lower die template plate 2 (2 - 4), the front lower die template plate 3 (2 - 5), and the right lower die template plate 1 (2 - 6) are welded rigidly to form the outer frame of the hot pressing lower die assembly (2). The middle horizontal lower die template plate 1 (2 - 7), the middle horizontal lower die template plate 2 (2 - 8), the middle horizontal lower die template plate 3 (2 - 9), and the middle horizontal lower die template plate 4 (2 - 10) are rigidly connected to the left lower die template plate 1 (2 - 2) and the front lower die template plate 2 (2 - 4) by template plate snap 4 (2 - 10 - 4), template plate slot hole 12 (2 - 2 - 3), and template plate slot hole 14 (2 - 4 - 3) respectively. The middle vertical lower die template plate 1 (2 - 11), the middle vertical lower die template plate 2 (2 - 12), the middle vertical lower die template plate 3 (2 - 13), the middle vertical lower die template plate 4 (2 - 14), the middle vertical lower die template plate 5 (2 - 15), the middle vertical lower die template plate 6 (2 - 16), and the middle vertical lower die template plate 7 (2 - 17) are rigidly connected to the rear lower die template plate (2 - 1) by template plate snap 5 (2 - 11 - 4) and template plate slot hole 11 (2 - 1 - 3) respectively.In the lower die, the first middle vertical plate (2-11), the second middle vertical plate (2-12), the third middle vertical plate (2-13), the fourth middle vertical plate (2-14), the fifth middle vertical plate (2-15), the sixth middle vertical plate (2-16), the seventh middle vertical plate (2-17) and the ninth characteristic curved surface plate (2-26) of the lower die are connected by plugging with the fifth template slot (2-11-3) and the fourth template slot (2-10-3), and the plugging assembly gap is 0.8-1.8 mm; the third middle vertical plate (2-13), the fourth middle vertical plate (2-14), the fifth middle vertical plate (2-15) of the lower die and the first front template (2-3) of the lower die are rigidly connected by the fifth template buckle (2-11-4) and the thirteenth template slot hole (2-3-3); the first characteristic curved surface plate (2-18), the second characteristic curved surface plate (2-19), the third characteristic curved surface plate (2-20), the fourth characteristic curved surface plate (2-21), the fifth characteristic curved surface plate (2-22), the sixth characteristic curved surface plate (2-23), the seventh characteristic curved surface plate (2-24), the eighth characteristic curved surface plate (2-25) of the lower die are characteristic curved surface plates, which are arranged at intervals between the first left template (2-2), the first middle vertical plate (2-11), the second middle vertical plate (2-12), the third middle vertical plate (2-13), the fourth middle vertical plate (2-14), the fifth middle vertical plate (2-15), the sixth middle vertical plate (2-16), the seventh middle vertical plate (2-17), the second front template (2-4) of the lower die, and are rigidly connected by welding. Here, the curvature change of the butt-welded template is relatively large. Adding characteristic curved surface plates can better ensure the surface accuracy and reduce the elastic deformation of the surface, resulting in more repair and correction in the later stage.;

[0011] The lower die rear template (2-1) consists of a substrate eleven (2-1-1), a surface eleven (2-1-2), seven template slot holes eleven (2-1-3), and two template holes eleven (2-1-4). The outer shape of the substrate eleven (2-1-1) is processed by a wire cutting equipment. The digital model of the surface eleven (2-1-2) is consistent with the thin shell surface (3). The spacing dimension of the template slot holes eleven (2-1-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product parts and the thin shell surface (3). The lower die left template one (2-2) consists of a substrate twelve (2-2-1), a surface twelve (2-2-2), three template slot holes twelve (2-2-3), and two template holes twelve (2-2-4). The outer shape of the substrate twelve (2-2-1) is processed by a wire cutting equipment. The digital model of the surface twelve (2-2-2) is consistent with the thin shell surface (3). The spacing dimension of the template slot holes twelve (2-2-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product parts and the thin shell surface (3). The lower die front template one (2-3) consists of a substrate thirteen (2-3-1), a surface thirteen (2-3-2), and three template slot holes thirteen (2-3-3). The outer shape of the substrate thirteen (2-3-1) is processed by a wire cutting equipment. The digital model of the surface thirteen (2-3-2) is consistent with the thin shell surface (3). The spacing dimension of the template slot holes thirteen (2-3-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product parts and the thin shell surface (3). The lower die front template two (2-4) consists of a substrate fourteen (2-4-1), a surface fourteen (2-4-2), three template slot holes fourteen (2-4-3), and two template holes fourteen (2-4-4). The outer shape of the substrate fourteen (2-4-1) is processed by a wire cutting equipment. The digital model of the surface fourteen (2-4-2) is consistent with the thin shell surface (3). The spacing dimension of the template slot holes fourteen (2-4-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product parts and the thin shell surface (3). The lower die front template three (2-5) and the lower die right template one (2-6) have the same structural composition. Taking the lower die front template three (2-5) as an example, the structural composition of these two templates is described. The lower die front template three (2-5) consists of a substrate fifteen (2-5-1), a surface fifteen (2-5-2), and a template hole fifteen (2-5-3). The outer shape of the substrate fifteen (2-5-1) is processed by a wire cutting equipment. The digital model of the surface fifteen (2-5-2) is consistent with the thin shell surface (3).The lower die feature surface template nine (2-26), the lower die middle horizontal template one (2-7), the lower die middle horizontal template two (2-8), the lower die middle horizontal template three (2-9), and the lower die middle horizontal template four (2-10) have the same structure. Taking the lower die middle horizontal template four (2-10) as an example, the structural composition of these five templates is described. The lower die middle horizontal template four (2-10) is composed of the matrix sixteen (2-10-1), the surface sixteen (2-10-2), seven template slots four (2-10-3), and two template buckles four (2-10-4). The outer shape of the matrix sixteen (2-10-1) is processed by wire cutting equipment, and the digital model of the surface sixteen (2-10-2) is consistent with the thin shell surface (3); The lower die middle vertical template one (2-11), the lower die middle vertical template two (2-12), the lower die middle vertical template three (2-13), the lower die middle vertical template four (2-14), the lower die middle vertical template five (2-15), the lower die middle vertical template six (2-16), and the lower die middle vertical template seven (2-17) have the same structure. Taking the lower die middle vertical template one (2-11) as an example, the structural composition of these seven templates is described. The lower die middle vertical template one (2-11) is composed of the matrix seventeen (2-11-1), the surface seventeen (2-11-2), the template slot five (2-11-3), and two template buckles five (2-11-4). The outer shape of the matrix seventeen (2-11-1) is processed by wire cutting equipment, and the digital model of the surface seventeen (2-11-2) is consistent with the thin shell surface (3); The lower die feature surface template one (2-18), the lower die feature surface template two (2-19), the lower die feature surface template seven (2-24), and the lower die feature surface template eight (2-25) have the same structure. Taking the lower die feature surface template one (2-18) as an example, the structural composition of these four templates is described. The lower die feature surface template one (2-18) is composed of the matrix six (2-18-1) and the surface six (2-18-2). The outer shape of the matrix six (2-18-1) is processed by wire cutting equipment, and the digital model of the surface six (2-18-2) is consistent with the thin shell surface (3); The lower die feature surface template three (2-20), the lower die feature surface template four (2-21), the lower die feature surface template five (2-22), and the lower die feature surface template six (2-23) have the same structure. Taking the lower die feature surface template three (2-20) as an example, the structural composition of these four templates is described. The lower die feature surface template three (2-20) is composed of the matrix eighteen (2-20-1) and the surface eighteen (2-20-2). The outer shape of the matrix eighteen (2-20-1) is processed by wire cutting equipment, and the digital model of the surface eighteen (2-20-2) is consistent with the thin shell surface (3).;

[0012] The thin-shell surface (3) is composed of a thin-shell surface one (3-1), a thin-shell surface two (3-2), a thin-shell reference plate (3-3), and a thin-shell reference plate (3-4). The thin-shell surface one (3-1) is symmetric with the thin-shell surface two (3-2), and the thin-shell reference plate (3-3) is symmetrically welded and rigidly connected to the thin-shell reference plate (3-4). Two positioning blind holes are respectively designed on the back surfaces of the thin-shell surface one (3-1) and the thin-shell surface two (3-2) for positioning during mold closing. The thin-shell surface one (3-1) and the thin-shell surface two (3-2) are hot-pressed and formed on the upper die assembly (1) and the hot-pressing lower die assembly (2).

[0013] The positioning pin assembly (4) is rigidly connected to the left lower die plate one (2-2), the front lower die plate two (2-4), and the middle transverse lower die plate three (2-9) by welding. The positioning pin assembly (4) is composed of a matrix nineteen (4-1) and a positioning pin hole (4-2). There are two positioning pin assemblies (4) in total. Positioning is carried out through two positioning pin holes (4-2), positioning pins, and the two positioning blind holes on the back surfaces of the thin-shell surface one (3-1) and the thin-shell surface two (3-2) to ensure the positions of the thin-shell surface one (3-1) and the thin-shell surface two (3-2) during mold closing.

[0014] A manufacturing method for a hot-pressing and forming tooling of a thin-shell surface of an aviation composite material mold specifically includes the following technological steps:

[0015] (1) Establish a three-dimensional model of an aviation composite material. Since such composite material parts are generally symmetric structures, modeling is carried out through three-dimensional software. According to the working conditions of thermal curing forming and finite element stress simulation analysis, a process digital model of Invar metal material with a thickness of 10 - 15 mm is established as the digital model of the thin-shell surface (3) of the mold. The three-dimensional model of the thin-shell surface (3) is established by symmetrically dividing it into two, that is, the digital models of the thin-shell surface one (3-1), the thin-shell surface two (3-2), the thin-shell reference plate one (3-3), and the thin-shell reference plate two (3-4) are established.

[0016] (2) Establish a 3D model of the hot pressing upper die assembly (1), which is made of ordinary steel plates with a thickness of 7 - 8 mm. Twenty-seven digital models of the form plates of the hot pressing upper die assembly (1) are established. They are assembled into a grid-like frame structure through slot insertion, snap and groove connection, and welding rigid connection methods. The grid interval size is 200 - 300 mm, and the connection gap for insertion and assembly is 0.8 - 1.8 mm. At the same time, at the places where the curvature of the thin shell surface changes greatly, ten characteristic surface form plates, namely, the upper die characteristic surface form plate one (1 - 18), the upper die characteristic surface form plate two (1 - 19), the upper die characteristic surface form plate three (1 - 20), the upper die characteristic surface form plate four (1 - 21), the upper die characteristic surface form plate five (1 - 22), the upper die characteristic surface form plate six (1 - 23), the upper die characteristic surface form plate seven (1 - 24), the upper die characteristic surface form plate eight (1 - 25), the upper die characteristic surface form plate nine (1 - 26), and the upper die characteristic surface form plate ten (1 - 27), are added and arranged at intervals between the upper die right form plate one (1 - 6), the upper die middle horizontal form plate four (1 - 10), the upper die middle longitudinal form plate one (1 - 11), the upper die middle longitudinal form plate two (1 - 12), the upper die middle longitudinal form plate three (1 - 13), the upper die middle longitudinal form plate four (1 - 14), the upper die middle longitudinal form plate five (1 - 15), the upper die middle longitudinal form plate six (1 - 16), the upper die middle longitudinal form plate seven (1 - 17), and the upper die left form plate one (1 - 2), so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce more maintenance and correction caused by elastic deformation of the thin shell surface in the later stage;

[0017] (3) Establish a 3D model of the hot pressing lower die assembly (2), which is made of ordinary steel plates with a thickness of 7 - 8 mm. Twenty-six digital models of the form plates of the hot pressing lower die assembly (2) are established. They are assembled into a grid-like frame structure through slot insertion, snap and groove connection, and welding rigid connection methods. The grid interval size is 200 - 300 mm, and the connection gap for insertion and assembly is 0.8 - 1.8 mm. At the same time, at the places where the curvature of the thin shell surface changes greatly, eight characteristic surface form plates, namely, the lower die characteristic surface form plate one (2 - 18), the lower die characteristic surface form plate two (2 - 19), the lower die characteristic surface form plate three (2 - 20), the lower die characteristic surface form plate four (2 - 21), the lower die characteristic surface form plate five (2 - 22), the lower die characteristic surface form plate six (2 - 23), the lower die characteristic surface form plate seven (2 - 24), and the lower die characteristic surface form plate eight (2 - 25), are added and arranged at intervals between the lower die left form plate one (2 - 2), the lower die middle longitudinal form plate one (2 - 11), the lower die middle longitudinal form plate two (2 - 12), the lower die middle longitudinal form plate three (2 - 13), the lower die middle longitudinal form plate four (2 - 14), the lower die middle longitudinal form plate five (2 - 15), the lower die middle longitudinal form plate six (2 - 16), the lower die middle longitudinal form plate seven (2 - 17), and the lower die front form plate two (2 - 4), so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce more maintenance and correction caused by elastic deformation of the thin shell surface in the later stage;

[0018] (4) Prepare the hot pressing upper die assembly (1) and the hot pressing lower die assembly (2). Prepare ordinary steel plates with a thickness of 7 - 8 mm. The 27 types of templates of the hot pressing upper die assembly (1) are processed by wire cutting equipment according to the digital model in step (2), and the 26 types of templates of the hot pressing lower die assembly (2) are laser cut according to the digital model in step (3). After being assembled together by inserting and combining the snap fasteners with the card slots and slots according to the shape requirements, the hot pressing upper die assembly (1) and the hot pressing lower die assembly (2) are welded and assembled. The grid frame type is mainly used to provide sufficient support for the upper templates, which can not only ensure strength but also reduce weight, save costs and quickly and evenly heat the thin shell surface (3) of the die;

[0019] (5) Prepare the positioning pin assembly (4). Establish the process digital model of the positioning pin assembly (4), process the positioning pin assembly (4) according to the process digital model and weld it at the positions of the left lower die template one (2 - 2), the front lower die template two (2 - 4), and the middle horizontal lower die template three (2 - 9) of the hot pressing lower die assembly (2);

[0020] (6) Prepare the thin shell reference plate one (3 - 3) or the thin shell reference plate two (3 - 4). Prepare Invar metal materials with a thickness of 10 - 15 mm, and process the thin shell reference plate one (3 - 3) or the thin shell reference plate two (3 - 4) by wire cutting equipment according to the digital model in step (1);

[0021] (7) Prepare materials for the thin shell surface one (3 - 1) or the thin shell surface two (3 - 2). Prepare Invar metal materials with a thickness of 10 - 15 mm. Unfold the thin shell surface one (3 - 1) or the thin shell surface two (3 - 2) into a flat form through 3D software in step (1), determine the shape and size after unfolding for blanking, and leave a 20 - mm margin for the outer dimension of the blanking. Drill two same positioning blind holes on the back of the prepared materials for the thin shell surface one (3 - 1) or the thin shell surface two (3 - 2) according to the positions of the two positioning pin assemblies (4) in step (4);

[0022] (8) Hot press forming to manufacture thin shell surface one (3-1) or thin shell surface two (3-2): ① Prepare the stock materials of thin shell surface one (3-1) or thin shell surface two (3-2) prepared in step (6) and put them into the heating furnace; ② The heating temperature range is 750-800 °C. Take out the stock materials of thin shell surface one (3-1) or thin shell surface two (3-2) and place them on the hot press lower die assembly (2); ③ Position through 2 positioning pin holes (4-2), positioning pins and 2 positioning blind holes on the back of thin shell surface one (3-1) and thin shell surface two (3-2) to ensure the position of thin shell surface one (3-1) or thin shell surface two (3-2) during hot press die closing; ④ Clamp the hot press upper die assembly (1) with a punching fixture for stamping. Wait for cooling and then take it out. After taking it out, conduct a preliminary inspection to check whether it conforms to the surface. If it is qualified, proceed to manufacture the next thin shell surface one (3-1) or thin shell surface two (3-2). If it is inconsistent, execute the process steps ①, ②, ③, and ④ again until it is qualified;

[0023] (9) Weld the thin shell surface (3) in groups. Open grooves on the back of the thin shell surface one (3-1), thin shell surface two (3-2), thin shell reference plate one (3-3), and thin shell reference plate two (3-4) processed in step (8) and step (6), and weld them into the thin shell surface (3) on the back as required. Finish machining the surface by CNC polishing;

[0024] (10) Air tightness test: ① Normal temperature air tightness: Place a vacuum bag on the upper surface of the thin shell surface (3). When it is an empty mold, install the bag and pump it to a vacuum of more than 0.09 MPa; close the air extraction port, keep the pressure for 5 minutes, and the pressure drop not exceeding 0.02 MPa is qualified; ② Enter the hot press autoclave high temperature air tightness: Pump the vacuum to 0.07 Mpa, heat up to 180 ± 5 °C, apply a pressure of 0.8 ± 0.02 MPa, keep the temperature and pressure for 30 minutes, close the vacuum pipeline, and the reading of the vacuum gauge should not drop by more than 0.017 MPa within 5 minutes to be qualified; Only when both the normal temperature air tightness and high temperature air tightness tests are qualified can it be determined that the air tightness of the thin shell surface (3) is qualified. Brief Description of the Drawings

[0025] Figure 1 It is a three-dimensional structural schematic diagram of the present invention.

[0026] Figure 2 It is a three-dimensional structural schematic diagram of the hot press upper die assembly (1) of the present invention.

[0027] Figure 3 It is a structural schematic diagram of the hot press lower die assembly (2) of the present invention.

[0028] Figure 4 It is a three-dimensional structural schematic diagram of the upper die rear plate (1-1) of the present invention.

[0029] Figure 5It is a schematic three-dimensional structure diagram of the upper die left template one (1-2) of the present invention.

[0030] Figure 6 It is a schematic three-dimensional structure diagram of the upper die front template one (1-3) of the present invention.

[0031] Figure 7 It is a schematic three-dimensional structure diagram of the upper die front template two (1-4) of the present invention.

[0032] Figure 8 It is a schematic three-dimensional structure diagram of the upper die middle horizontal template one (1-7) of the present invention.

[0033] Figure 9 It is a schematic three-dimensional structure diagram of the upper die middle horizontal template four (1-10) of the present invention.

[0034] Figure 10 It is a schematic three-dimensional structure diagram of the upper die middle vertical template one (1-11) of the present invention.

[0035] Figure 11 It is a schematic three-dimensional structure diagram of the upper die middle vertical template three (1-13) of the present invention.

[0036] Figure 12 It is a schematic three-dimensional structure diagram of the upper die characteristic curved surface template one (1-18) of the present invention.

[0037] Figure 13 It is a schematic three-dimensional structure diagram of the lower die rear template (2-1) of the present invention.

[0038] Figure 14 It is a schematic three-dimensional structure diagram of the lower die left template one (2-2) of the present invention.

[0039] Figure 15 It is a schematic three-dimensional structure diagram of the lower die front template one (2-3) of the present invention.

[0040] Figure 16 It is a schematic three-dimensional structure diagram of the lower die front template two (2-4) of the present invention.

[0041] Figure 17 It is a schematic three-dimensional structure diagram of the lower die front template three (2-5) of the present invention.

[0042] Figure 18 It is a schematic three-dimensional structure diagram of the lower die middle horizontal template four (2-10) of the present invention.

[0043] Figure 19 It is a schematic three-dimensional structure diagram of the lower die middle vertical template one (2-11) of the present invention.

[0044] Figure 20 It is a schematic three-dimensional structure diagram of the lower die characteristic curved surface template one (2-18) of the present invention.

[0045] Figure 21 It is a schematic three-dimensional structure diagram of the lower die feature curved surface plate three (2 - 20) of the present invention.

[0046] Figure 22 It is a schematic three-dimensional structure diagram of the positioning pin assembly (4) of the present invention.

[0047] Figure 23 It is a schematic three-dimensional structure diagram of the hot curing forming die for manufacturing aviation composite materials of the present invention.

[0048] Figure 24 It is a schematic three-dimensional structure diagram of the thin shell surface (3) of the hot curing forming die of the present invention.

[0049] Figure 25 It is a schematic three-dimensional structure diagram of the thin shell surface (3 - 1) of the present invention.

[0050] 1 - Hot pressing upper die assembly, 2 - Hot pressing lower die assembly, 3 - Thin shell surface, 4 - Positioning pin assembly. Detailed implementation manners

[0051] This technical solution can also be realized by the following technical measures and the present invention will be further described below with reference to the accompanying drawings:

[0052] Figure 1 It is a schematic three-dimensional structure diagram of the present invention. The thin shell surface hot pressing forming tooling for aviation composite material mold is composed of a hot pressing upper die assembly (1), a hot pressing lower die assembly (2), a thin shell surface (3), and a positioning pin assembly (4). It is characterized in that: the hot pressing upper die assembly (1), the hot pressing lower die assembly (2) and the positioning pin assembly (4) form a hot pressing forming tooling, and the thin shell surface (3) of the aviation composite material mold is manufactured by hot pressing forming.

[0053] Figure 2It is a schematic three-dimensional structure diagram of the hot pressing upper die assembly (1) of the present invention. The hot pressing upper die assembly (1) is composed of 27 types of template plates, made of ordinary steel plates with a thickness of 7 - 8 mm, and is formed into a grid-like frame structure by using slot insertion, snap-fastener and card slot connection, and welding rigid connection methods among them; the hot pressing upper die assembly (1) is composed of an upper die rear template plate (1-1), an upper die left template plate one (1-2), an upper die front template plate one (1-3), an upper die front template plate two (1-4), an upper die front template plate three (1-5), an upper die right template plate one (1-6), an upper die middle horizontal template plate one (1-7), an upper die middle horizontal template plate two (1-8), an upper die middle horizontal template plate three (1-9), an upper die middle horizontal template plate four (1-10), an upper die middle vertical template plate one (1-11), an upper die middle vertical template plate two (1-12), an upper die middle vertical template plate three (1-13), an upper die middle vertical template plate four (1-14), an upper die middle vertical template plate five (1-15), an upper die middle vertical template plate six (1-16), an upper die middle vertical template plate seven (1-17), an upper die characteristic curved surface template plate one (1-18), an upper die characteristic curved surface template plate two (1-19), an upper die characteristic curved surface template plate three (1-20), an upper die characteristic curved surface template plate four (1-21), an upper die characteristic curved surface template plate five (1-22), an upper die characteristic curved surface template plate six (1-23), an upper die characteristic curved surface template plate seven (1-24), an upper die characteristic curved surface template plate eight (1-25), an upper die characteristic curved surface template plate nine (1-26), and an upper die characteristic curved surface template plate ten (1-27). The 27 types of template plates are rigidly connected into a grid-like frame structure through slot insertion, snap-fastener and card slot. The grid interval size is 200 - 300 m, and the specific number of grids and interval size are determined by the composite material product parts and the thin shell surface (3); the upper die rear template plate (1-1), the upper die left template plate one (1-2), the upper die front template plate one (1-3), the upper die front template plate two (1-4), the upper die front template plate three (1-5), and the upper die right template plate one (1-6) are welded rigidly to form the outer frame of the hot pressing upper die assembly (1); the upper die rear template plate (1-1) is rigidly connected to the upper die middle vertical template plate one (1-11), the upper die middle vertical template plate two (1-12), the upper die middle vertical template plate six (1-16), and the upper die middle vertical template plate seven (1-17) by using the template plate card slot hole one (1-1-3) and the template plate snap-fastener two (1-11-4); the upper die rear template plate (1-1) is rigidly connected to the upper die middle vertical template plate two (1-12), the upper die middle vertical template plate three (1-13), and the upper die middle vertical template plate four (1-14) by using the template plate card slot hole one (1-1-3) and the template plate snap-fastener three (1-12-4); the upper die front template plate two (1-4) is rigidly connected to the upper die middle vertical template plate two (1-12), the upper die middle vertical template plate three (1-13), and the upper die middle vertical template plate four (1-14) by using the template plate card slot hole three (1-4-3) and the template plate snap-fastener three (1-12-4);The upper die middle horizontal template one (1-7), the upper die middle horizontal template two (1-8), and the upper die middle horizontal template three (1-9) are rigidly connected to the upper die left template one (1-2) and the upper die right template one (1-6) respectively by the template snap one (1-7-4) and the template slot hole two (1-2-3); the upper die middle vertical template one (1-11), the upper die middle vertical template two (1-12), the upper die middle vertical template three (1-13), the upper die middle vertical template four (1-14), the upper die middle vertical template five (1-15), the upper die middle vertical template six (1-16), and the upper die middle vertical template seven (1-17) are inserted and connected to the upper die middle horizontal template one (1-7), the upper die middle horizontal template two (1-8), and the upper die middle horizontal template three (1-9) respectively by the template slot six (1-10-3) and the template slot one (1-7-3), and the insertion assembly gap is 0.8 - 1.8 mm; the upper die middle horizontal template four (1-10) is inserted and connected to the upper die middle vertical template one (1-11), the upper die middle vertical template two (1-12), the upper die middle vertical template three (1-13), the upper die middle vertical template four (1-14), the upper die middle vertical template five (1-15), the upper die middle vertical template six (1-16), and the upper die middle vertical template seven (1-17) by the plate slot two (1-10-3) and the plate slot one (1-7-3), and the insertion assembly gap is 0.8 - 1.8 mm; the upper die characteristic curved surface templates one (1-18), two (1-19), three (1-20), four (1-21), five (1-22), six (1-23), seven (1-24), eight (1-25), nine (1-26), and ten (1-27) are characteristic curved surface templates, which are arranged at intervals between the upper die right template one (1-6), the upper die middle horizontal template four (1-10), the upper die middle vertical template one (1-11), the upper die middle vertical template two (1-12), the upper die middle vertical template three (1-13), the upper die middle vertical template four (1-14), the upper die middle vertical template five (1-15), the upper die middle vertical template six (1-16), the upper die middle vertical template seven (1-17), and the upper die left template one (1-2), and are rigidly connected by welding to form a space grid framework. At the places where the curvature of the thin shell surface changes greatly, the number of characteristic curved surface templates is increased, so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce the more maintenance and correction caused by the elastic deformation of the thin shell surface in the later stage.;

[0054] Figure 3It is a schematic structural diagram of the hot pressing lower die assembly (2) of the present invention. The hot pressing lower die assembly (2) is composed of 26 types of templates, made of ordinary steel plates with a thickness of 7-8 mm, and a grid-like frame structure is formed by using slot insertion, snap connection with card slots and welding rigid connection methods among them; the hot pressing lower die assembly (2) is composed of a rear lower die template (2-1), a first left lower die template (2-2), a first front lower die template (2-3), a second front lower die template (2-4), a third front lower die template (2-5), a first right lower die template (2-6), a first middle horizontal lower die template (2-7), a second middle horizontal lower die template (2-8), a third middle horizontal lower die template (2-9), a fourth middle horizontal lower die template (2-10), a first middle vertical lower die template (2-11), a second middle vertical lower die template (2-12), a third middle vertical lower die template (2-13), a fourth middle vertical lower die template (2-14), a fifth middle vertical lower die template (2-15), a sixth middle vertical lower die template (2-16), a seventh middle vertical lower die template (2-17), a first lower die feature curved surface template (2-18), a second lower die feature curved surface template (2-19), a third lower die feature curved surface template (2-20), a fourth lower die feature curved surface template (2-21), a fifth lower die feature curved surface template (2-22), a sixth lower die feature curved surface template (2-23), a seventh lower die feature curved surface template (2-24), an eighth lower die feature curved surface template (2-25), and a ninth lower die feature curved surface template (2-26). The 26 types of templates are rigidly connected in a grid-like frame structure with equal interval distances through slot insertion, snap connection with card slots. The grid interval size is 200-300 mm, and the specific number of grids and interval size are determined by the composite material product parts and the thin shell surface (3); the rear lower die template (2-1), the first left lower die template (2-2), the first front lower die template (2-3), the second front lower die template (2-4), the third front lower die template (2-5), and the first right lower die template (2-6) are welded rigidly to form the outer frame of the hot pressing lower die assembly (2); the first middle horizontal lower die template (2-7), the second middle horizontal lower die template (2-8), the third middle horizontal lower die template (2-9), and the fourth middle horizontal lower die template (2-10) are rigidly connected to the first left lower die template (2-2) and the second front lower die template (2-4) respectively by using a fourth template snap (2-10-4), a twelfth template card slot hole (2-2-3), and a fourteenth template card slot hole (2-4-3); the first middle vertical lower die template (2-11), the second middle vertical lower die template (2-12), the third middle vertical lower die template (2-13), the fourth middle vertical lower die template (2-14), the fifth middle vertical lower die template (2-15), the sixth middle vertical lower die template (2-16), and the seventh middle vertical lower die template (2-17) are rigidly connected to the rear lower die template (2-1) respectively by using a fifth template snap (2-11-4) and an eleventh template card slot hole (2-1-3).The longitudinal plate one (2-11), longitudinal plate two (2-12), longitudinal plate three (2-13), longitudinal plate four (2-14), longitudinal plate five (2-15), longitudinal plate six (2-16), longitudinal plate seven (2-17) in the lower mold and the lower mold characteristic curved surface plate nine (2-26) are connected by plugging with the template slot five (2-11-3) and the template slot four (2-10-3), and the plugging assembly gap is 0.8 - 1.8 mm; the longitudinal plate three (2-13), longitudinal plate four (2-14), longitudinal plate five (2-15) in the lower mold and the front plate one (2-3) of the lower mold are rigidly connected by the template buckle five (2-11-4) and the template card slot hole thirteen (2-3-3); the positioning pin assembly (4) is rigidly connected to the left plate one (2-2) of the lower mold, the front plate two (2-4) of the lower mold, and the middle transverse plate three (2-9) of the lower mold by welding; the lower mold characteristic curved surface plates one (2-18), two (2-19), three (2-20), four (2-21), five (2-22), six (2-23), seven (2-24), eight (2-25) are characteristic curved surface plates, which are arranged at intervals between the left plate one (2-2) of the lower mold, the longitudinal plate one (2-11) of the lower mold, the longitudinal plate two (2-12) of the lower mold, the longitudinal plate three (2-13) of the lower mold, the longitudinal plate four (2-14) of the lower mold, the longitudinal plate five (2-15) of the lower mold, the longitudinal plate six (2-16) of the lower mold, the longitudinal plate seven (2-17) of the lower mold, and the front plate two (2-4) of the lower mold, and are rigidly connected by welding. Here, the curvature of the spliced plates changes greatly. Adding characteristic curved surface plates can better ensure the accuracy of the surface and reduce more maintenance and correction caused by elastic deformation of the surface.;

[0055] Figure 4 It is a three-dimensional structural schematic diagram of the rear plate (1-1) of the upper mold of the present invention. The rear plate (1-1) of the upper mold is composed of a base one (1-1-1), a surface one (1-1-2), 7 template card slot holes one (1-1-3), and 2 template holes one (1-1-4). The outer shape of the base one (1-1-1) is processed by a wire cutting device. The digital model of the surface one (1-1-2) is consistent with the thin shell surface (3). The spacing dimension of the template card slot holes one (1-1-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product parts and the thin shell surface (3).

[0056] Figure 5It is a three-dimensional structural schematic diagram of the first left upper die plate (1-2) of the present invention. The first left upper die plate (1-2) has the same structure as the first right upper die plate (1-6). The first left upper die plate (1-2) is representative and illustrates the structural composition of the two die plates. The first left upper die plate (1-2) is composed of a second base body (1-2-1), a second profile surface (1-2-2), three second die plate slot holes (1-2-3), and two second die plate holes (1-2-4). The outer shape of the second base body (1-2-1) is processed by a wire cutting device. The digital model of the second profile surface (1-2-2) is consistent with the thin shell profile surface (3). The spacing dimension of the second die plate slot holes (1-1-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell profile surface (3).

[0057] Figure 6 It is a three-dimensional structural schematic diagram of the first front upper die plate (1-3) of the present invention. The first front upper die plate (1-3) has the same structure as the third front upper die plate (1-5). The first front upper die plate (1-3) is representative and illustrates the structural composition of the two die plates. The first front upper die plate (1-3) is composed of a third base body (1-3-1), a third profile surface (1-3-2), and a third die plate hole (1-3-3). The outer shape of the third base body (1-3-1) is processed by a wire cutting device. The digital model of the third profile surface (1-3-2) is consistent with the thin shell profile surface (3).

[0058] Figure 7 It is a three-dimensional structural schematic diagram of the second front upper die plate (1-4) of the present invention. The second front upper die plate (1-4) is composed of a fourth base body (1-4-1), a fourth profile surface (1-4-2), and a third die plate slot hole (1-4-3). The outer shape of the fourth base body (1-4-1) is processed by a wire cutting device. The digital model of the fourth profile surface (1-4-2) is consistent with the thin shell profile surface (3). The spacing dimension of the third die plate slot hole (1-4-3) is 200 - 300 mm and is consistent with the spacing of the slot holes of the rear upper die plate (1-1).

[0059] Figure 8 It is a three-dimensional structural schematic diagram of the first middle horizontal upper die plate (1-7) of the present invention. The first middle horizontal upper die plate (1-7), the second middle horizontal upper die plate (1-8), and the third middle horizontal upper die plate (1-9) have the same structural composition. Taking the first middle horizontal upper die plate (1-7) as an example, it illustrates the structural composition of these three die plates. The first middle horizontal upper die plate (1-7) is composed of a seventh base body (1-7-1), a seventh profile surface (1-7-2), seven first die plate slots (1-7-3), and two first die plate buckles (1-7-4). The outer shape of the seventh base body (1-7-1) is processed by a wire cutting device. The digital model of the seventh profile surface (1-7-2) is consistent with the thin shell profile surface (3). The spacing dimension of the first die plate slots (1-7-3) is 200 - 300 mm and is consistent with the spacing of the slot holes of the rear upper die plate (1-1).

[0060] Figure 9 It is a three-dimensional structural schematic diagram of the fourth middle cross-plate (1-10) of the upper die of the present invention. The fourth middle cross-plate (1-10) of the upper die is composed of a base body five (1-10-1), a profile five (1-10-2), and seven template slots six (1-10-3). The outer shape of the base body five (1-10-1) is processed by a wire cutting device. The digital model of the profile five (1-10-2) is consistent with the thin shell profile (3). The spacing dimension of the template slots six (1-10-3) is 200-300 mm, which is consistent with the spacing of the slot holes of the rear template (1-1) of the upper die.

[0061] Figure 10 It is a three-dimensional structural schematic diagram of the first middle longitudinal plate (1-11) of the upper die of the present invention. The first middle longitudinal plate (1-11), the second middle longitudinal plate (1-12), the sixth middle longitudinal plate (1-16), and the seventh middle longitudinal plate (1-17) of the upper die have the same structural composition. Taking the first middle longitudinal plate (1-11) as an example, the structural composition of these four templates is described. The first middle longitudinal plate (1-11) is composed of a base body eight (1-11-1), a profile eight (1-11-2), three template slots two (1-11-3), and a template buckle two (1-11-4). The outer shape of the base body eight (1-11-1) is processed by a wire cutting device. The digital model of the profile eight (1-11-2) is consistent with the thin shell profile (3). The spacing dimension of the template slots two (1-11-3) is 200-300 mm, which is consistent with the spacing of the slot holes of the left template one (1-2) of the upper die.

[0062] Figure 11 It is a three-dimensional structural schematic diagram of the third middle longitudinal plate (1-13) of the upper die of the present invention. The third middle longitudinal plate (1-13), the fourth middle longitudinal plate (1-14), and the fifth middle longitudinal plate (1-15) of the upper die have the same structural composition. Taking the third middle longitudinal plate (1-13) as an example, the structural composition of these three templates is described. The third middle longitudinal plate (1-13) is composed of a base body nine (1-13-1), a profile nine (1-13-2), three template slots three (1-13-3), and two template buckles three (1-13-4). The outer shape of the base body nine (1-13-1) is processed by a wire cutting device. The digital model of the profile nine (1-13-2) is consistent with the thin shell profile (3). The spacing dimension of the template slots three (1-13-3) is 200-300 mm, which is consistent with the spacing of the slot holes of the left template one (1-2) of the upper die.

[0063] Figure 12It is a three-dimensional structural schematic diagram of the first upper die characteristic curved surface template (1-18) of the present invention. The first upper die characteristic curved surface template (1-18), the second upper die characteristic curved surface template (1-19), the third upper die characteristic curved surface template (1-20), the fourth upper die characteristic curved surface template (1-21), the fifth upper die characteristic curved surface template (1-22), the sixth upper die characteristic curved surface template (1-23), the seventh upper die characteristic curved surface template (1-24), the eighth upper die characteristic curved surface template (1-25), the ninth upper die characteristic curved surface template (1-26), and the tenth upper die characteristic curved surface template (1-27) have the same structure. Taking the first upper die characteristic curved surface template (1-18) as an example, the structural composition of these 10 characteristic curved surface templates is described. The first upper die characteristic curved surface template (1-18) is composed of a tenth base body (1-18-1) and a tenth surface (1-18-2). The outer shape of the tenth base body (1-18-1) is processed by a wire cutting device, and the digital model of the tenth surface (1-18-2) is consistent with the thin shell surface (3).

[0064] Figure 13 It is a three-dimensional structural schematic diagram of the rear lower die template (2-1) of the present invention. The rear lower die template (2-1) is composed of an eleventh base body (2-1-1), an eleventh surface (2-1-2), seven template slot holes eleven (2-1-3), and two template holes eleven (2-1-4). The outer shape of the eleventh base body (2-1-1) is processed by a wire cutting device, the digital model of the eleventh surface (2-1-2) is consistent with the thin shell surface (3), and the spacing dimension of the template slot holes eleven (2-1-3) is 200-300 mm. The specific spacing dimension is determined by the composite material product parts and the thin shell surface (3).

[0065] Figure 14 It is a three-dimensional structural schematic diagram of the first left lower die template (2-2) of the present invention. The first left lower die template (2-2) is composed of a twelfth base body (2-2-1), a twelfth surface (2-2-2), three template slot holes twelve (2-2-3), and two template holes twelve (2-2-4). The outer shape of the twelfth base body (2-2-1) is processed by a wire cutting device, the digital model of the twelfth surface (2-2-2) is consistent with the thin shell surface (3), and the spacing dimension of the template slot holes twelve (2-2-3) is 200-300 mm. The specific spacing dimension is determined by the composite material product parts and the thin shell surface (3).

[0066] Figure 15It is a three-dimensional structural schematic diagram of the first front lower die plate (2-3) of the present invention. The first front lower die plate (2-3) is composed of the thirteenth base body (2-3-1), the thirteenth surface (2-3-2), and three thirteenth die plate slot holes (2-3-3). The outer shape of the thirteenth base body (2-3-1) is processed by a wire cutting device. The digital model of the thirteenth surface (2-3-2) is consistent with the thin shell surface (3). The spacing dimension of the thirteenth die plate slot holes (2-3-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product parts and the thin shell surface (3).

[0067] Figure 16 It is a three-dimensional structural schematic diagram of the second front lower die plate (2-4) of the present invention. The second front lower die plate (2-4) is composed of the fourteenth base body (2-4-1), the fourteenth surface (2-4-2), three fourteenth die plate slot holes (2-4-3), and two fourteenth die plate holes (2-4-4). The outer shape of the fourteenth base body (2-4-1) is processed by a wire cutting device. The digital model of the fourteenth surface (2-4-2) is consistent with the thin shell surface (3). The spacing dimension of the fourteenth die plate slot holes (2-4-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product parts and the thin shell surface (3).

[0068] Figure 17 It is a three-dimensional structural schematic diagram of the third front lower die plate (2-5) of the present invention. The third front lower die plate (2-5) and the first right lower die plate (2-6) have the same structural composition. Taking the third front lower die plate (2-5) as an example, the structural composition of these two die plates is described. The third front lower die plate (2-5) is composed of the fifteenth base body (2-5-1), the fifteenth surface (2-5-2), and the fifteenth die plate hole (2-5-3). The outer shape of the fifteenth base body (2-5-1) is processed by a wire cutting device. The digital model of the fifteenth surface (2-5-2) is consistent with the thin shell surface (3).

[0069] Figure 18 It is a three-dimensional structural schematic diagram of the fourth middle lower die plate (2-10) of the present invention. The ninth characteristic surface die plate of the lower die (2-26), the first middle lower die plate (2-7), the second middle lower die plate (2-8), the third middle lower die plate (2-9), and the fourth middle lower die plate (2-10) have the same structural composition. Taking the fourth middle lower die plate (2-10) as an example, the structural composition of these five die plates is described. The fourth middle lower die plate (2-10) is composed of the sixteenth base body (2-10-1), the sixteenth surface (2-10-2), seven fourth die plate slots (2-10-3), and two fourth die plate buckles (2-10-4). The outer shape of the sixteenth base body (2-10-1) is processed by a wire cutting device. The digital model of the sixteenth surface (2-10-2) is consistent with the thin shell surface (3).

[0070] Figure 19It is a three-dimensional structure schematic diagram of the first longitudinal plate (2-11) in the lower mold of the present invention. The first longitudinal plate (2-11), the second longitudinal plate (2-12), the third longitudinal plate (2-13), the fourth longitudinal plate (2-14), the fifth longitudinal plate (2-15), the sixth longitudinal plate (2-16), and the seventh longitudinal plate (2-17) in the lower mold have the same structure. Taking the first longitudinal plate (2-11) in the lower mold as an example, the structural composition of these seven types of plates is described. The first longitudinal plate (2-11) in the lower mold is composed of the seventeenth base (2-11-1), the seventeenth profile surface (2-11-2), the fifth template slot (2-11-3), and two fifth template buckles (2-11-4). The outer shape of the seventeenth base (2-11-1) is processed by a wire cutting device, and the digital model of the seventeenth profile surface (2-11-2) is consistent with the thin shell profile surface (3).

[0071] Figure 20 It is a three-dimensional structure schematic diagram of the first characteristic curved surface plate (2-18) in the lower mold of the present invention. The first characteristic curved surface plate (2-18), the second characteristic curved surface plate (2-19), the seventh characteristic curved surface plate (2-24), and the eighth characteristic curved surface plate (2-25) in the lower mold have the same structure. Taking the first characteristic curved surface plate (2-18) in the lower mold as an example, the structural composition of these four types of plates is described. The first characteristic curved surface plate (2-18) in the lower mold is composed of the sixth base (2-18-1) and the sixth profile surface (2-18-2). The outer shape of the sixth base (2-18-1) is processed by a wire cutting device, and the digital model of the sixth profile surface (2-18-2) is consistent with the thin shell profile surface (3).

[0072] Figure 21 It is a three-dimensional structure schematic diagram of the third characteristic curved surface plate (2-20) in the lower mold of the present invention. The third characteristic curved surface plate (2-20), the fourth characteristic curved surface plate (2-21), the fifth characteristic curved surface plate (2-22), and the sixth characteristic curved surface plate (2-23) in the lower mold have the same structure. Taking the third characteristic curved surface plate (2-20) in the lower mold as an example, the structural composition of these four types of plates is described. The third characteristic curved surface plate (2-20) in the lower mold is composed of the eighteenth base (2-20-1) and the eighteenth profile surface (2-20-2). The outer shape of the eighteenth base (2-20-1) is processed by a wire cutting device, and the digital model of the eighteenth profile surface (2-20-2) is consistent with the thin shell profile surface (3).

[0073] Figure 22It is a schematic three-dimensional structure diagram of the positioning pin assembly (4) of the present invention. The positioning pin assembly (4) is composed of a base body XIX (4-1) and positioning pin holes (4-2). There are a total of 2 positioning pin assemblies (4), which are positioned through 2 positioning pin holes (4-2), positioning pins, and 2 positioning blind holes on the back of the thin shell surface I (3-1) and the thin shell surface II (3-2) to ensure the positions of the thin shell surface I (3-1) and the thin shell surface II (3-2) during mold closing.

[0074] Figure 23 It is a schematic three-dimensional structure diagram of the hot curing forming mold for manufacturing aviation composite materials of the present invention. Figure 24 It is a schematic three-dimensional structure diagram of the thin shell surface (3) of the hot curing forming mold of the present invention. Figure 25 It is a schematic three-dimensional structure diagram of the thin shell surface (3-1) of the present invention. The thin shell surface (3) is symmetrically composed of the thin shell surface I (3-1) and the thin shell surface II (3-2), and is rigidly connected by welding. 2 positioning blind holes are respectively designed on the backs of the thin shell surface I (3-1) and the thin shell surface II (3-2) for positioning during mold closing. The thin shell surface I (3-1) and the thin shell surface II (3-2) are hot pressed and formed on the upper mold assembly (1) and the hot pressing lower mold assembly (2).

[0075] The manufacturing method of the hot pressing forming tooling for the thin shell surface of the aviation composite material mold specifically includes the following technological steps:

[0076] (1) Establish a three-dimensional model of the aviation composite material. Since such composite material parts are generally symmetric structures, modeling is carried out through three-dimensional software. According to the working conditions of hot curing forming and finite element stress simulation analysis, a process digital model of Invar metal material with a thickness of 10-15 mm is established as the digital model of the thin shell surface (3) of the mold. The three-dimensional model of the thin shell surface (3) is established by dividing it symmetrically into two, that is, the digital models of the thin shell surface I (3-1), the thin shell surface II (3-2), the thin shell reference plate I (3-3), and the thin shell reference plate II (3-4) are established.

[0077] (2) Establish the 3D model of the hot pressing upper die assembly (1), which is made of ordinary steel plates with a thickness of 7 - 8 mm. Twenty-seven types of plate digital models of the hot pressing upper die assembly (1) are established. They are composed of a grid-like frame structure through slot insertion, snap and slot connection, and welding rigid connection methods. The grid interval size is 200 - 300 mm, and the insertion assembly connection gap is 0.8 - 1.8 mm. At the same time, at the places where the curvature of the thin shell surface changes greatly, ten characteristic surface plates are added, namely the upper die characteristic surface plate one (1 - 18), the upper die characteristic surface plate two (1 - 19), the upper die characteristic surface plate three (1 - 20), the upper die characteristic surface plate four (1 - 21), the upper die characteristic surface plate five (1 - 22), the upper die characteristic surface plate six (1 - 23), the upper die characteristic surface plate seven (1 - 24), the upper die characteristic surface plate eight (1 - 25), the upper die characteristic surface plate nine (1 - 26), and the upper die characteristic surface plate ten (1 - 27). They are arranged at intervals between the upper die right plate one (1 - 6), the upper die middle horizontal plate four (1 - 10), the upper die middle longitudinal plate one (1 - 11), the upper die middle longitudinal plate two (1 - 12), the upper die middle longitudinal plate three (1 - 13), the upper die middle longitudinal plate four (1 - 14), the upper die middle longitudinal plate five (1 - 15), the upper die middle longitudinal plate six (1 - 16), the upper die middle longitudinal plate seven (1 - 17), and the upper die left plate one (1 - 2), so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce more maintenance and correction caused by elastic deformation of the thin shell surface in the later stage;

[0078] (3) Establish the 3D model of the hot pressing lower die assembly (2), which is made of ordinary steel plates with a thickness of 7 - 8 mm. Twenty-six types of plate digital models of the hot pressing lower die assembly (2) are established. They are composed of a grid-like frame structure through slot insertion, snap and slot connection, and welding rigid connection methods. The grid interval size is 200 - 300 mm, and the insertion assembly connection gap is 0.8 - 1.8 mm. At the same time, at the places where the curvature of the thin shell surface changes greatly, eight characteristic surface plates are added, namely the lower die characteristic surface plate one (2 - 18), the lower die characteristic surface plate two (2 - 19), the lower die characteristic surface plate three (2 - 20), the lower die characteristic surface plate four (2 - 21), the lower die characteristic surface plate five (2 - 22), the lower die characteristic surface plate six (2 - 23), the lower die characteristic surface plate seven (2 - 24), and the lower die characteristic surface plate eight (2 - 25). They are arranged at intervals between the lower die left plate one (2 - 2), the lower die middle longitudinal plate one (2 - 11), the lower die middle longitudinal plate two (2 - 12), the lower die middle longitudinal plate three (2 - 13), the lower die middle longitudinal plate four (2 - 14), the lower die middle longitudinal plate five (2 - 15), the lower die middle longitudinal plate six (2 - 16), the lower die middle longitudinal plate seven (2 - 17), and the lower die front plate two (2 - 4), so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce more maintenance and correction caused by elastic deformation of the thin shell surface in the later stage;

[0079] (4) Prepare the hot pressing upper die assembly (1) and the hot pressing lower die assembly (2). Prepare ordinary steel plates with a thickness of 7 - 8 mm. The 27 types of templates of the hot pressing upper die assembly (1) are processed by wire cutting equipment according to the digital model in step (2), and the 26 types of templates of the hot pressing lower die assembly (2) are laser cut according to the digital model in step (3). After being assembled together by inserting and connecting with buckles, grooves and slots according to the shape requirements, the hot pressing upper die assembly (1) and the hot pressing lower die assembly (2) are welded and assembled. The grid framework is mainly used to provide sufficient support for the upper templates, which can not only ensure strength but also reduce weight, save costs and quickly and uniformly heat the thin shell surface (3) of the die;

[0080] (5) Prepare the positioning pin assembly (4). Establish the process digital model of the positioning pin assembly (4), and process and weld the positioning pin assembly (4) at the positions of the left lower die template one (2 - 2), the front lower die template two (2 - 4), and the middle horizontal lower die template three (2 - 9) of the hot pressing lower die assembly (2);

[0081] (6) Prepare the thin shell reference plate one (3 - 3) or the thin shell reference plate two (3 - 4). Prepare Invar metal materials with a thickness of 10 - 15 mm, and process the thin shell reference plate one (3 - 3) or the thin shell reference plate two (3 - 4) by wire cutting equipment according to the digital model in step (1);

[0082] (7) Prepare materials for the thin shell surface one (3 - 1) or the thin shell surface two (3 - 2). Prepare Invar metal materials with a thickness of 10 - 15 mm. Unfold the thin shell surface one (3 - 1) or the thin shell surface two (3 - 2) into a flat plate form through 3D software in step (1), determine the shape and size after unfolding for blanking, and leave a 20 - mm margin for the outer dimension of the blanking. Drill two same positioning blind holes on the back of the materials for the thin shell surface one (3 - 1) or the thin shell surface two (3 - 2) according to the positions of the two positioning pin assemblies (4) in step (4);

[0083] (8) Hot press forming to manufacture thin shell surface one (3-1) or thin shell surface two (3-2): ① Prepare the stock materials of thin shell surface one (3-1) or thin shell surface two (3-2) prepared in step (6) and put them into the heating furnace; ② Heat at a temperature range of 750-800 °C, take out the stock materials of thin shell surface one (3-1) or thin shell surface two (3-2) and place them on the hot press lower die assembly (2); ③ Position through 2 positioning pin holes (4-2), positioning pins and 2 positioning blind holes on the back of thin shell surface one (3-1) and thin shell surface two (3-2) to ensure the position of thin shell surface one (3-1) or thin shell surface two (3-2) during hot press clamping; ④ Clamp the hot press upper die assembly (1) with a punching fixture for stamping, wait for cooling and then take out. After taking out, initially conduct inspection to check if it conforms to the surface. If it is qualified, proceed to manufacture the next thin shell surface one (3-1) or thin shell surface two (3-2). If it is inconsistent, execute the process steps ①, ②, ③, ④ again until it is qualified;

[0084] (9) Assemble and weld the thin shell surface (3). Open bevels on the back of thin shell surface one (3-1), thin shell surface two (3-2), thin shell reference plate one (3-3) and thin shell reference plate two (3-4) processed in step (8) and step (6), and assemble and weld them on the back into the thin shell surface (3) as required;

[0085] (10) Air tightness test: ① Normal temperature air tightness: Place a vacuum bag on the upper surface of the thin shell surface (3). When it is an empty mold, install the bag and pump to a vacuum of more than 0.09 MPa; close the air extraction port, keep the pressure for 5 minutes, and the pressure drop not exceeding 0.02 MPa is qualified; ② Enter the hot press autoclave for high temperature air tightness: Pump to a vacuum of 0.07 Mpa, heat up to 180 ± 5 °C, apply a pressure of 0.8 ± 0.02 MPa, keep the temperature and pressure for 30 minutes, close the vacuum pipeline, and the vacuum gauge reading should not drop by more than 0.017 MPa within 5 minutes to be qualified; Only when both the normal temperature air tightness and high temperature air tightness tests are qualified can it be determined that the air tightness of the thin shell surface (3) is qualified.

Claims

1. A hot pressing tooling for the thin shell surface of an aviation composite material mold, which is composed of a hot pressing upper die assembly (1), a hot pressing lower die assembly (2), a thin shell surface (3), and a positioning pin assembly (4), and is characterized in that: The hot pressing upper die assembly (1), the hot pressing lower die assembly (2) and the positioning pin assembly (4) form a hot pressing forming tooling, and the thin shell surface (3) of the composite material mold for aviation is manufactured by hot pressing forming; the hot pressing upper die assembly (1) is composed of 27 types of plates, made of ordinary steel plates with a thickness of 7 - 8 mm, and are connected by slot insertion, snap and slot connection and welding rigid connection methods to form a grid - type frame structure. The hot pressing upper die assembly (1) is composed of the rear upper die plate (1 - 1), the left upper die plate one (1 - 2), the front upper die plate one (1 - 3), the front upper die plate two (1 - 4), the front upper die plate three (1 - 5), the right upper die plate one (1 - 6), the middle horizontal upper die plate one (1 - 7), the middle horizontal upper die plate two (1 - 8), the middle horizontal upper die plate three (1 - 9), the middle horizontal upper die plate four (1 - 10), the middle vertical upper die plate one (1 - 11), the middle vertical upper die plate two (1 - 12), the middle vertical upper die plate three (1 - 13), the middle vertical upper die plate four (1 - 14), the middle vertical upper die plate five (1 - 15), the middle vertical upper die plate six (1 - 16), the middle vertical upper die plate seven (1 - 17), the upper die feature surface plate one (1 - 18), the upper die feature surface plate two (1 - 19), the upper die feature surface plate three (1 - 20), the upper die feature surface plate four (1 - 21), the upper die feature surface plate five (1 - 22), the upper die feature surface plate six (1 - 23), the upper die feature surface plate seven (1 - 24), the upper die feature surface plate eight (1 - 25), the upper die feature surface plate nine (1 - 26), and the upper die feature surface plate ten (1 - 27). The 27 types of plates are rigidly connected to form a grid - type frame structure through slot insertion, snap and slot connection. The grid interval size is 200 - 300 mm, and the specific number of grids and interval size are determined by the composite material product parts and the thin shell surface (3); the hot pressing lower die assembly (2) is composed of 26 types of plates, made of ordinary steel plates with a thickness of 7 - 8 mm, and are connected by slot insertion, snap and slot connection and welding rigid connection methods to form a grid - type frame structure;The hot pressing lower die assembly (2) is composed of a lower die rear template (2-1), a lower die left template one (2-2), a lower die front template one (2-3), a lower die front template two (2-4), a lower die front template three (2-5), a lower die right template one (2-6), a lower die middle horizontal template one (2-7), a lower die middle horizontal template two (2-8), a lower die middle horizontal template three (2-9), a lower die middle horizontal template four (2-10), a lower die middle vertical template one (2-11), a lower die middle vertical template two (2-12), a lower die middle vertical template three (2-13), a lower die middle vertical template four (2-14), a lower die middle vertical template five (2-15), a lower die middle vertical template six (2-16), a lower die middle vertical template seven (2-17), a lower die characteristic curved surface template one (2-18), a lower die characteristic curved surface template two (2-19), a lower die characteristic curved surface template three (2-20), a lower die characteristic curved surface template four (2-21), a lower die characteristic curved surface template five (2-22), a lower die characteristic curved surface template six (2-23), a lower die characteristic curved surface template seven (2-24), a lower die characteristic curved surface template eight (2-25), and a lower die characteristic curved surface template nine (2-26). The 26 templates are rigidly connected to each other through slot insertion, snap-fasteners and card slots to form an equally spaced grid structure. The grid spacing dimension is 200 - 300 mm, and the specific number of grids and spacing dimension are determined by the composite material product parts and the thin shell surface (3). The thin shell surface (3) is symmetrically composed of a thin shell surface one (3-1) and a thin shell surface two (3-2), and is rigidly connected by welding. Two positioning blind holes are respectively designed on the back of the thin shell surface one (3-1) and the thin shell surface two (3-2) for positioning during mold closing. The thin shell surface one (3-1) and the thin shell surface two (3-2) are hot-pressed and formed on the upper die assembly (1) and the hot pressing lower die assembly (2). The positioning pin assembly (4) is rigidly connected to the lower die left template one (2-2), the lower die front template two (2-4), and the lower die middle horizontal template three (2-9) by welding.

2. The hot pressing forming tooling for the thin shell surface of the composite material mold for aviation according to claim 1, characterized in that: The upper die rear template (1-1), the upper die left template one (1-2), the upper die front template one (1-3), the upper die front template two (1-4), the upper die front template three (1-5), and the upper die right template one (1-6) are rigidly connected by welding to form the outer frame of the hot pressing upper die assembly (1); the upper die rear template (1-1) is rigidly connected to the upper die middle longitudinal template one (1-11), the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template six (1-16), and the upper die middle longitudinal template seven (1-17) by the template slot hole one (1-1-3) and the template buckle two (1-11-4); the upper die rear template (1-1) is rigidly connected to the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template three (1-13), and the upper die middle longitudinal template four (1-14) by the template slot hole one (1-1-3) and the template buckle three (1-12-4); the upper die front template two (1-4) is rigidly connected to the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template three (1-13), and the upper die middle longitudinal template four (1-14) by the template slot hole three (1-4-3) and the template buckle three (1-12-4); the upper die middle transverse template one (1-7), the upper die middle transverse template two (1-8), and the upper die middle transverse template three (1-9) are respectively rigidly connected to the upper die left template one (1-2) and the upper die right template one (1-6) by the template buckle one (1-7-4) and the template slot hole two (1-2-3); the upper die middle longitudinal template one (1-11), the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template three (1-13), the upper die middle longitudinal template four (1-14), the upper die middle longitudinal template five (1-15), the upper die middle longitudinal template six (1-16), and the upper die middle longitudinal template seven (1-17) are respectively connected by inserting and connecting with the upper die middle transverse template one (1-7), the upper die middle transverse template two (1-8), and the upper die middle transverse template three (1-9) through the template slot two (1-11-3) and the template slot one (1-7-3), and the inserting and assembling gap is 0.8 - 1.8 mm; the upper die middle transverse template four (1-10) is connected to the upper die middle longitudinal template one (1-11), the upper die middle longitudinal template two (1-12), the upper die middle longitudinal template three (1-13), the upper die middle longitudinal template four (1-14), the upper die middle longitudinal template five (1-15), the upper die middle longitudinal template six (1-16), and the upper die middle longitudinal template seven (1-17) by inserting and connecting with the template slot six (1-10-3) and the template slot one (1-7-3), and the inserting and assembling gap is 0.8 - 1.8 mm; the upper die feature surface template one (1-18), upper die feature surface template two (1-19), upper die feature surface template three (1-20), upper die feature surface template four (1-21), upper die feature surface template five (1-22), upper die feature surface template six (1-23), upper die feature surface template seven (1-24), upper die feature surface template eight (1-25), upper die feature surface template nine (1-26), and upper die feature surface template ten (1-27) are feature surface templates, which are arranged at intervals between the upper die right template one (1-6), upper die middle horizontal template four (1-10), upper die middle vertical template one (1-11), upper die middle vertical template two (1-12), upper die middle vertical template three (1-13), upper die middle vertical template four (1-14), upper die middle vertical template five (1-15), upper die middle vertical template six (1-16), upper die middle vertical template seven (1-17), and upper die left template one (1-2), and are rigidly connected by welding to form a space grid framework. At the places where the curvature of the thin shell surface changes greatly, the number of feature surface types is increased, so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce the more maintenance and correction in the later stage caused by the elastic deformation of the thin shell surface.

3. The hot pressing forming tooling for the thin shell surface of the composite material mold for aviation according to claim 1, characterized in that: The lower die rear template (2-1), the lower die left template one (2-2), the lower die front template one (2-3), the lower die front template two (2-4), the lower die front template three (2-5), and the lower die right template one (2-6) are rigidly connected by welding to form the outer frame of the hot pressing lower die assembly (2); the lower die middle horizontal template one (2-7), the lower die middle horizontal template two (2-8), the lower die middle horizontal template three (2-9), and the lower die middle horizontal template four (2-10) are rigidly connected to the lower die left template one (2-2) and the lower die front template two (2-4) respectively by plate snap fasteners four (2-10-4), template slot holes twelve (2-2-3), and template slot holes fourteen (2-4-3); the lower die middle vertical template one (2-11), the lower die middle vertical template two (2-12), the lower die middle vertical template three (2-13), the lower die middle vertical template four (2-14), the lower die middle vertical template five (2-15), the lower die middle vertical template six (2-16), and the lower die middle vertical template seven (2-17) are rigidly connected to the lower die rear template (2-1) respectively by template snap fasteners five (2-11-4) and template slot holes eleven (2-1-3); the lower die middle vertical template one (2-11), the lower die middle vertical template two (2-12), the lower die middle vertical template three (2-13), the lower die middle vertical template four (2-14), the lower die middle vertical template five (2-15), the lower die middle vertical template six (2-16), and the lower die middle vertical template seven (2-17) are connected to the lower die feature curved surface template nine (2-26) by plugging and connecting with template slots five (2-11-3) and template slots four (2-10-3), and the plugging and assembling gap is 0.8 - 1.8 mm; the lower die middle vertical template three (2-13), the lower die middle vertical template four (2-14), and the lower die middle vertical template five (2-15) are rigidly connected to the lower die front template one (2-3) by template snap fasteners five (2-11-4) and template slot holes thirteen (2-3-3); the lower die feature curved surface template one (2-18), the lower die feature curved surface template two (2-19), the lower die feature curved surface template three (2-20), the lower die feature curved surface template four (2-21), the lower die feature curved surface template five (2-22), the lower die feature curved surface template six (2-23), the lower die feature curved surface template seven (2-24), and the lower die feature curved surface template eight (2-25) are feature curved surface templates, which are arranged at intervals between the lower die left template one (2-2), the lower die middle vertical template one (2-11), the lower die middle vertical template two (2-12), the lower die middle vertical template three (2-13), the lower die middle vertical template four (2-14), the lower die middle vertical template five (2-15), the lower die middle vertical template six (2-16), the lower die middle vertical template seven (2-17), and the lower die front template two (2-4), and are rigidly connected by welding. Here, the curvature of the butt-welded template changes greatly, and adding feature curved surface templates can better ensure the accuracy of the surface and reduce the elastic deformation of the surface, resulting in less maintenance and correction in the later stage.

4. The hot pressing forming tooling for the thin shell surface of the composite material mold for aviation according to claim 1 or 2, characterized in that: The upper die rear template (1-1) is composed of a first base body (1-1-1), a first mold surface (1-1-2), seven first template slot holes (1-1-3), and two first template holes (1-1-4). The outer shape of the first base body (1-1-1) is processed by a wire cutting device. The digital model of the first mold surface (1-1-2) is consistent with the thin shell mold surface (3). The spacing dimension of the first template slot holes (1-1-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell mold surface (3). The left upper die template one (1-2) and the right upper die template one (1-6) have the same structure. Taking the left upper die template one (1-2) as an example, the structural composition of these two templates is described. The left upper die template one (1-2) is composed of a second base body (1-2-1), a second mold surface (1-2-2), three second template slot holes (1-2-3), and two second template holes (1-2-4). The outer shape of the second base body (1-2-1) is processed by a wire cutting device. The digital model of the second mold surface (1-2-2) is consistent with the thin shell mold surface (3). The spacing dimension of the second template slot holes (1-2-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell mold surface (3). The front upper die template one (1-3) and the front upper die template three (1-5) have the same structure. Taking the front upper die template one (1-3) as an example, the structural composition of these two templates is described. The front upper die template one (1-3) is composed of a third base body (1-3-1), a third mold surface (1-3-2), and a third template hole (1-3-3). The outer shape of the third base body (1-3-1) is processed by a wire cutting device. The digital model of the third mold surface (1-3-2) is consistent with the thin shell mold surface (3). The front upper die template two (1-4) is composed of a fourth base body (1-4-1), a fourth mold surface (1-4-2), and a third template slot hole (1-4-3). The outer shape of the fourth base body (1-4-1) is processed by a wire cutting device. The digital model of the fourth mold surface (1-4-2) is consistent with the thin shell mold surface (3). The spacing dimension of the third template slot hole (1-4-3) is 200 - 300 mm and is consistent with the spacing of the slot holes of the upper die rear template (1-1). The upper die middle horizontal template one (1-7), the upper die middle horizontal template two (1-8), and the upper die middle horizontal template three (1-9) have the same structural composition. Taking the upper die middle horizontal template one (1-7) as an example, the structural composition of these three templates is described. The upper die middle horizontal template one (1-7) is composed of a seventh base body (1-7-1), a seventh mold surface (1-7-2), seven first template slots (1-7-3), and two first template buckles (1-7-4). The outer shape of the seventh base body (1-7-1) is processed by a wire cutting device. The digital model of the seventh mold surface (1-7-2) is consistent with the thin shell mold surface (3). The spacing dimension of the first template slots (1-7-3) is 200 - 300 mm and is consistent with the spacing of the slot holes of the upper die rear template (1-1).The upper die middle horizontal template four (1-10) is composed of a matrix five (1-10-1), a profile five (1-10-2), and seven template slots six (1-10-3). The outer shape of the matrix five (1-10-1) is processed by a wire cutting device. The digital model of the profile five (1-10-2) is consistent with the thin shell profile (3). The spacing dimension of the template slots six (1-10-3) is 200 - 300 mm, which is consistent with the spacing of the slot holes of the upper die rear template (1-1). The upper die middle vertical template one (1-11), the upper die middle vertical template two (1-12), the upper die middle vertical template six (1-16), and the upper die middle vertical template seven (1-17) have the same structural composition. Taking the upper die middle vertical template one (1-11) as an example, the structural composition of these four templates is described. The upper die middle vertical template one (1-11) is composed of a matrix eight (1-11-1), a profile eight (1-11-2), three template slots two (1-11-3), and a template buckle two (1-11-4). The outer shape of the matrix eight (1-11-1) is processed by a wire cutting device. The digital model of the profile eight (1-11-2) is consistent with the thin shell profile (3). The spacing dimension of the template slots two (1-11-3) is 200 - 300 mm, which is consistent with the spacing of the slot holes of the upper die left template one (1-2). The upper die middle vertical template three (1-13), the upper die middle vertical template four (1-14), and the upper die middle vertical template five (1-15) have the same structural composition. Taking the upper die middle vertical template three (1-13) as an example, the structural composition of these three templates is described. The upper die middle vertical template three (1-13) is composed of a matrix nine (1-13-1), a profile nine (1-13-2), three template slots three (1-13-3), and two template buckles six (1-13-4). The outer shape of the matrix nine (1-13-1) is processed by a wire cutting device. The digital model of the profile nine (1-13-2) is consistent with the thin shell profile (3). The spacing dimension of the template slots three (1-13-3) is 200 - 300 mm, which is consistent with the spacing of the slot holes of the upper die left template one (1-2). The upper die characteristic curved surface templates one (1-18) to ten (1-27) have the same structural composition. Taking the upper die characteristic curved surface template one (1-18) as an example, the structural composition of these 10 characteristic curved surface templates is described. The upper die characteristic curved surface template one (1-18) is composed of a matrix ten (1-18-1) and a profile ten (1-18-2). The outer shape of the matrix ten (1-18-1) is processed by a wire cutting device. The digital model of the profile ten (1-18-2) is consistent with the thin shell profile (3).; 5. The hot pressing forming tooling for the thin shell surface of the composite material mold for aviation according to claim 1 or 3, characterized in that: The lower die rear template (2-1) is composed of a substrate eleven (2-1-1), a profile eleven (2-1-2), seven template slot holes eleven (2-1-3), and two template holes eleven (2-1-4). The outer shape of the substrate eleven (2-1-1) is processed by a wire cutting device. The digital model of the profile eleven (2-1-2) is consistent with the thin shell profile (3). The spacing dimension of the template slot holes eleven (2-1-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell profile (3). The lower die left template one (2-2) is composed of a substrate twelve (2-2-1), a profile twelve (2-2-2), three template slot holes twelve (2-2-3), and two template holes twelve (2-2-4). The outer shape of the substrate twelve (2-2-1) is processed by a wire cutting device. The digital model of the profile twelve (2-2-2) is consistent with the thin shell profile (3). The spacing dimension of the template slot holes twelve (2-2-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell profile (3). The lower die front template one (2-3) is composed of a substrate thirteen (2-3-1) and a profile thirteen (2-3-2) and three template slot holes thirteen (2-3-3). The outer shape of the substrate thirteen (2-3-1) is processed by a wire cutting device. The digital model of the profile thirteen (2-3-2) is consistent with the thin shell profile (3). The spacing dimension of the template slot holes thirteen (2-3-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell profile (3). The lower die front template two (2-4) is composed of a substrate fourteen (2-4-1), a profile fourteen (2-4-2), three template slot holes fourteen (2-4-3), and two template holes fourteen (2-4-4). The outer shape of the substrate fourteen (2-4-1) is processed by a wire cutting device. The digital model of the profile fourteen (2-4-2) is consistent with the thin shell profile (3). The spacing dimension of the template slot holes fourteen (2-4-3) is 200 - 300 mm, and the specific spacing dimension is determined by the composite material product part and the thin shell profile (3). The lower die front template three (2-5) and the lower die right template one (2-6) have the same structural composition. Taking the lower die front template three (2-5) as an example, the structural composition of these two templates is described. The lower die front template three (2-5) is composed of a substrate fifteen (2-5-1), a profile fifteen (2-5-2), and a template hole fifteen (2-5-3). The outer shape of the substrate fifteen (2-5-1) is processed by a wire cutting device. The digital model of the profile fifteen (2-5-2) is consistent with the thin shell profile (3).The lower die feature curved surface template nine (2-26), the lower die middle horizontal template one (2-7), the lower die middle horizontal template two (2-8), the lower die middle horizontal template three (2-9), and the lower die middle horizontal template four (2-10) have the same structure. Taking the lower die middle horizontal template four (2-10) as an example, the structural composition of these five templates is described. The lower die middle horizontal template four (2-10) is composed of the base sixteen (2-10-1), the surface sixteen (2-10-2), seven template slots four (2-10-3), and two template buckles four (2-10-4). The outer shape of the base sixteen (2-10-1) is processed by wire cutting equipment, and the digital model of the surface sixteen (2-10-2) is consistent with the thin shell surface (3); The lower die middle vertical template one (2-11), the lower die middle vertical template two (2-12), the lower die middle vertical template three (2-13), the lower die middle vertical template four (2-14), the lower die middle vertical template five (2-15), the lower die middle vertical template six (2-16), and the lower die middle vertical template seven (2-17) have the same structure. Taking the lower die middle vertical template one (2-11) as an example, the structural composition of these seven templates is described. The lower die middle vertical template one (2-11) is composed of the base seventeen (2-11-1), the surface seventeen (2-11-2), the template slot five (2-11-3), and two template buckles five (2-11-4). The outer shape of the base seventeen (2-11-1) is processed by wire cutting equipment, and the digital model of the surface seventeen (2-11-2) is consistent with the thin shell surface (3); The lower die feature curved surface template one (2-18), the lower die feature curved surface template two (2-19), the lower die feature curved surface template seven (2-24), and the lower die feature curved surface template eight (2-25) have the same structure. Taking the lower die feature curved surface template one (2-18) as an example, the structural composition of these four templates is described. The lower die feature curved surface template one (2-18) is composed of the base six (2-18-1) and the surface six (2-18-2). The outer shape of the base six (2-18-1) is processed by wire cutting equipment, and the digital model of the surface six (2-18-2) is consistent with the thin shell surface (3); The lower die feature curved surface template three (2-20), the lower die feature curved surface template four (2-21), the lower die feature curved surface template five (2-22), and the lower die feature curved surface template six (2-23) have the same structure. Taking the lower die feature curved surface template three (2-20) as an example, the structural composition of these four templates is described. The lower die feature curved surface template three (2-20) is composed of the base eighteen (2-20-1) and the surface eighteen (2-20-2). The outer shape of the base eighteen (2-20-1) is processed by wire cutting equipment, and the digital model of the surface eighteen (2-20-2) is consistent with the thin shell surface (3).; 6. The hot pressing forming tooling for the thin shell surface of the composite material mold for aviation according to claim 1, characterized in that: The positioning pin assembly (4) consists of a base XIX (4-1) and positioning pin holes (4-2). There are two positioning pin assemblies (4) in total. They are positioned through two positioning pin holes (4-2), positioning pins, and two positioning blind holes on the back of the thin shell surface I (3-1) and the thin shell surface II (3-2) to ensure the positions of the thin shell surface I (3-1) and the thin shell surface II (3-2) during mold closing.

7. The manufacturing method of the thin-shell surface hot pressing forming tooling for the aviation composite material mold according to claim 1, characterized in that: The manufacturing method of the hot pressing forming tooling for the thin shell surface of the aviation composite material mold specifically includes the following technological steps: (1) Establish a three-dimensional model of the aviation composite material. Since such composite material parts are generally symmetric structures, modeling is carried out through three-dimensional software. According to the working conditions of thermal curing forming and finite element stress simulation analysis, a process digital model of Invar metal material with a thickness of 10-15 mm is established as the digital model of the thin shell surface (3) of the mold. The three-dimensional model of the thin shell surface (3) is established by splitting it symmetrically into two, that is, the digital models of the thin shell surface I (3-1), the thin shell surface II (3-2), the thin shell reference plate I (3-3), and the thin shell reference plate II (3-4) are established; (2) Establish a three-dimensional model of the hot pressing upper mold assembly (1), which is made of ordinary steel plates with a thickness of 7-8 mm. Twenty-seven types of plate digital models of the hot pressing upper mold assembly (1) are established. They are composed of a grid-like frame structure by using slot plugging, snap and slot connection, and welding rigid connection methods among each other. The grid interval dimension is 200-300 mm, and the plugging and assembling connection gap is 0.8-1.8 mm; at the same time, at the places where the curvature of the thin shell surface changes greatly, ten characteristic curved surface plates, namely the upper mold characteristic curved surface plate I (1-18), the upper mold characteristic curved surface plate II (1-19), the upper mold characteristic curved surface plate III (1-20), the upper mold characteristic curved surface plate IV (1-21), the upper mold characteristic curved surface plate V (1-22), the upper mold characteristic curved surface plate VI (1-23), the upper mold characteristic curved surface plate VII (1-24), the upper mold characteristic curved surface plate VIII (1-25), the upper mold characteristic curved surface plate IX (1-26), and the upper mold characteristic curved surface plate X (1-27), are added and arranged at intervals between the upper mold right plate I (1-6), the upper mold middle transverse plate IV (1-10), the upper mold middle longitudinal plate I (1-11), the upper mold middle longitudinal plate II (1-12), the upper mold middle longitudinal plate III (1-13), the upper mold middle longitudinal plate IV (1-14), the upper mold middle longitudinal plate V (1-15), the upper mold middle longitudinal plate VI (1-16), the upper mold middle longitudinal plate VII (1-17), and the upper mold left plate I (1-2), so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce more maintenance and correction caused by elastic deformation of the thin shell surface in the later stage; (3) Establish a 3D model of the hot pressing lower die assembly (2), which is made of ordinary steel plates with a thickness of 7 - 8 mm. Twenty-six types of template digital models of the hot pressing lower die assembly (2) are established. They are assembled into a grid-frame structure by means of slot insertion, snap-fastener and slot connection, and welding rigid connection. The grid interval size is 200 - 300 mm, and the insertion assembly connection gap is 0.8 - 1.8 mm. At the same time, at the places where the curvature of the thin shell surface changes greatly, eight characteristic surface templates, namely the lower die characteristic surface template one (2-18), the lower die characteristic surface template two (2-19), the lower die characteristic surface template three (2-20), the lower die characteristic surface template four (2-21), the lower die characteristic surface template five (2-22), the lower die characteristic surface template six (2-23), the lower die characteristic surface template seven (2-24), and the lower die characteristic surface template eight (2-25), are added. They are arranged at intervals between the lower die left template one (2-2), the lower die middle longitudinal template one (2-11), the lower die middle longitudinal template two (2-12), the lower die middle longitudinal template three (2-13), the lower die middle longitudinal template four (2-14), the lower die middle longitudinal template five (2-15), the lower die middle longitudinal template six (2-16), the lower die middle longitudinal template seven (2-17), and the lower die front template two (2-4), so as to increase the stiffness, obtain better thin shell surface accuracy, and reduce the more maintenance and correction caused by the elastic deformation of the thin shell surface in the later stage; (4) Prepare the hot pressing upper die assembly (1) and the hot pressing lower die assembly (2). Prepare ordinary steel plates with a thickness of 7 - 8 mm. Twenty-seven types of templates of the hot pressing upper die assembly (1) are processed by wire cutting equipment according to the digital model in step (2). Twenty-six types of templates of the hot pressing lower die assembly (2) are laser cut according to the digital model in step (3). After being assembled together by snap-fastener and slot insertion according to the shape requirements, the hot pressing upper die assembly (1) and the hot pressing lower die assembly (2) are welded and assembled. The main function of the grid frame is to provide sufficient support for the upper templates, which can not only ensure the strength but also reduce the weight, save costs and quickly and evenly heat the thin shell surface of the die (3); (5) Prepare the positioning pin assembly (4). Establish the process digital model of the positioning pin assembly (4). Process the positioning pin assembly (4) according to the process digital model and weld it at the positions of the lower die left template one (2-2), the lower die front template two (2-4), and the lower die middle transverse template three (2-9) of the hot pressing lower die assembly (2); (6) Prepare the thin shell reference plate one (3-3) or the thin shell reference plate two (3-4). Prepare Invar metal materials with a thickness of 10 - 15 mm. Process the thin shell reference plate one (3-3) or the thin shell reference plate two (3-4) by wire cutting equipment according to the digital model in step (1); Prepare materials for the thin shell surface one (3-1) or the thin shell surface two (3-2). Prepare Invar metal materials with a thickness of 10-15 mm. Unfold the thin shell surface one (3-1) or the thin shell surface two (3-2) into a flat plate form through 3D software according to step (1), determine the shape and size after unfolding for blanking, and leave a 20-mm margin for the outer dimension of the blanking. Drill two identical positioning blind holes on the back of the material prepared for the thin shell surface one (3-1) or the thin shell surface two (3-2) according to the positions of the two positioning pin assemblies (4) in step (4). Hot press forming to manufacture the thin shell surface one (3-1) or the thin shell surface two (3-2): ① Put the material prepared for the thin shell surface one (3-1) or the thin shell surface two (3-2) prepared in step (6) into the heating furnace. ② Heat within the temperature range of 750-800 °C, and take out the material prepared for the thin shell surface one (3-1) or the thin shell surface two (3-2) and place it on the hot press lower die assembly (2). ③ Position through the two positioning pin holes (4-2), positioning pins and the two positioning blind holes on the back of the thin shell surface one (3-1) and the thin shell surface two (3-2) to ensure the position of the thin shell surface one (3-1) or the thin shell surface two (3-2) during hot press clamping. ④ Clamp the hot press upper die assembly (1) with a punching fixture for stamping, wait for cooling and then take out. After taking out, initially conduct inspections to check whether it conforms to the surface. If it is qualified, proceed to manufacture the next thin shell surface one (3-1) or the thin shell surface two (3-2). If it is inconsistent, repeat steps ①, ②, ③, and ④ until it is qualified. Group weld the thin shell surface (3). Open bevels on the back of the thin shell surface one (3-1), the thin shell surface two (3-2), the thin shell reference plate one (3-3), and the thin shell reference plate two (3-4) processed in step (8) and step (6), and group weld them into the thin shell surface (3) on the back according to requirements. Air tightness test: ① Normal temperature air tightness: Place a vacuum bag on the upper surface of the thin shell surface (3). When it is an empty mold, evacuate the bag to a vacuum of more than 0.09 MPa; close the air extraction port, keep the pressure for 5 minutes, and if the pressure drop is not more than 0.02 MPa, it is qualified. ② Enter the autoclave for high temperature air tightness: Evacuate to 0.07 Mpa, heat up to 180 ± 5 °C, apply a pressure of 0.8 ± 0.02 MPa, keep the temperature and pressure for 30 minutes, close the vacuum pipeline, and the reading of the vacuum gauge shall not drop by more than 0.017 MPa within 5 minutes to be qualified. Only when both the normal temperature air tightness and the high temperature air tightness tests are qualified can it be determined that the air tightness of the thin shell surface (3) is qualified.

Images