阅读说明：本技术 一种捕获型抗弹道冲击复合材料风扇机匣及其制造方法 (Capturing type ballistic impact resistant composite material fan casing and manufacturing method thereof ) 是由 孙建波 刘永佼 易凯 杨智勇 张建宝 左小彪 张艺萌 于 2020-09-30 设计创作，主要内容包括：本发明提供了一种捕获型抗弹道冲击复合材料风扇机匣及其制造方法,该风扇机匣为回转体结构,包括两法兰区域、两非包容区域和包容区域,其中,所述法兰区域位于风扇机匣的中部,为两端至中部逐渐增厚的变厚度区域。本发明的风扇机匣设计重点针对包容区域,包容区域为主要承担抗叶片断裂后的冲击区域,针对高速冲击的特定破坏模式与机理,采用与之对应的多相结构,利用其每一相的最佳力学性能来应对冲击,从而提升整体构件抗弹道冲击的结构效率,并使整体结构更易捕获高速叶片弹体,有利于控制一次及二次损伤,增强结构可靠性,解决了叶片破裂的捕获包容问题。(The invention provides a capture type ballistic impact resistant composite material fan casing and a manufacturing method thereof. The fan case is mainly designed aiming at a containing region which is an impact region mainly bearing the resistance to blade fracture, and aiming at a specific damage mode and mechanism of high-speed impact, the fan case adopts a corresponding multiphase structure and utilizes the optimal mechanical property of each phase to deal with the impact, so that the structural efficiency of the integral member for resisting ballistic impact is improved, the integral structure is easier to capture high-speed blade bullets, primary and secondary damage is favorably controlled, the structural reliability is enhanced, and the problem of capturing and containing the blade fracture is solved.)

1. A capture type ballistic impact resistant composite material fan case is characterized in that the fan case is of a revolving body structure and comprises two flange regions, two non-containing regions and a containing region, wherein the flange regions are located at two ends of the fan case, the thickness of the flange regions is 12-17 mm, and the maximum outer diameter is set according to the pneumatic design requirement of an aircraft engine; the non-containing area is arranged between the containing area and the flange area, and the thickness of the non-containing area is 12-17 mm; the flange region is located in the middle of the fan casing and is a variable thickness region gradually thickened from two ends to the middle, the maximum thickness of the middle is 28-35 mm, and the flange region is of a multi-phase structure correspondingly selected according to damage modes of different stages of high-speed impact.

2. The fan case according to claim 1, wherein the flange region is formed by curing a high modulus carbon fiber reinforced high tenacity epoxy resin prepreg, and the high modulus carbon fiber reinforced high tenacity epoxy resin prepreg is selected from one or a combination of unidirectional tapes of M40J or M55J or twill weaves thereof.

3. The fan case according to claim 2, wherein when the high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg is a unidirectional tape, the flange area is formed by laying on a mold in an automatic filament laying mode, the number of the filament bundles can be selected from single filament bundles, 4 filament bundles and 8 filament bundles, and the angle is selected to be [ ± 60/0 ];

when the high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg is twill fabric, the flange area is formed by being laid on a die in a winding mode.

4. The fan case as set forth in claim 1, wherein said flange region and non-containment region meet at an R-angle, both an inner R-angle and an outer R-angle being R5-R20.

5. The fan case according to claim 1, wherein the uncontained area is formed by curing a high modulus carbon fiber reinforced high tenacity epoxy prepreg, and the thickness and lay-up pattern are consistent with those of the flange area.

6. The fan case according to claim 1, wherein the containment region comprises, from inside to outside of the flow passage surface, a compression shear resistant layer, a tensile layer, a fence layer, an energy absorbing layer, and an anti-deformation layer;

the compression-shear resistant layer is made of a high-modulus carbon fiber reinforced composite material or an aramid fiber reinforced composite material; the tensile modulus of the high-modulus carbon fibers in the high-modulus carbon fiber reinforced composite material is more than 350GPa, and the tensile strength of the aramid fibers in the aramid fiber reinforced composite material is more than 4.2 GPa;

the tensile layer is made of a high-strength carbon fiber reinforced composite material, and the tensile strength of high-strength carbon fibers in the high-strength carbon fiber reinforced composite material is more than 5.5 GPa;

the fence layer is a glue film containing a metal net, and the peeling strength of the roller is required to be more than 40N/25 mm;

the energy absorption layer is made of a small-tow aramid fiber satin fabric reinforced composite material or small-tow aramid fiber cloth and an epoxy resin composition with the mass fraction of 20-40%, wherein the linear density of aramid fibers is less than 40 tex;

the anti-deformation layer is a metal alloy back plate, and the tensile strength is greater than 350 MPa.

7. The fan case according to claim 6, wherein when the high modulus carbon fiber reinforced composite material is selected as the compression-resistant layer, the fabric design is satin fabric; when the anti-pressure shear layer is made of aramid fiber reinforced composite materials, the fabric is designed in a satin weave mode.

8. The fan case according to claim 6, wherein the compression-resistant layer is between 17 wt% and 20 wt% in the containment region;

the proportion of the tensile layer in the containing area is between 17 wt% and 33 wt%;

the proportion of the fence layer in the containing area is between 2 and 3 weight percent;

the proportion of the energy absorption layer in the containing region is between 17 and 25 weight percent;

the thickness of the anti-deformation layer is 1-1.5 mm.

9. The fan case according to claim 6, wherein the thickness of the housing area is changed by changing the laying range of the anti-pressure-shear layer, the tensile layer, the fence layer, the energy absorbing layer and the deformation preventing layer, and the area corresponding to the fan blade of the flying fan in the housing area has the anti-pressure-shear layer, the tensile layer, the fence layer, the energy absorbing layer and the deformation preventing layer.

10. The fan case according to claim 6, wherein, in addition to the deformation prevention layer, when the types of fibers in the composite materials selected between the adjacent two layers of the compression-resistant shear layer, the tensile layer, the fence layer and the energy absorption layer are different, a transition layer of 1mm to 3mm can be arranged between the adjacent two layers, the transition layer is a mixed fiber reinforced composite material, and the mixed fiber is a fiber used in the composite materials of the adjacent two layers.

11. A manufacturing method of a capture type ballistic impact resistant composite material fan casing is characterized by comprising the following steps:

step 1, paving a 1-2 mm environment protection layer on the whole fan casing die, wherein the environment protection layer is a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg and is used for forming a flange area and an uncontained area;

step 2, paving a pressure-resistant shear layer of the passivated elastomer in the range of the corresponding containing area on the fan case die, and sucking and compacting the glue;

step 3, paving prepreg in a range corresponding to the whole fan case on a fan case die, forming a tensile layer in a range corresponding to a containing region, and forming a flange region and a non-containing region together with an environment protection layer outside the range corresponding to the containing region;

step 4, paving a fence layer and an energy absorption layer in the range of the corresponding containing area on the fan case mould, and performing glue absorption and compaction;

step 5, paving a 1-5 mm environment protection layer on the whole fan casing die, wherein the environment protection layer is a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg and is used for forming a flange area and an uncontaining area;

step 6, curing the paved material, performing size measurement and nondestructive testing after demolding and cleaning, and performing machining according to the specification after the testing requirements are met;

and 7, anodizing the split aluminum alloy panel by adopting a medium-temperature adhesive film, and then bonding and curing the aluminum alloy panel in a containing area.

Technical Field

The invention belongs to the technical field of structural composite material manufacturing, and particularly relates to a capture type ballistic impact resistant composite material fan casing and a manufacturing method thereof.

Background

The fan casing is the largest stationary part in an aircraft engine with a large bypass ratio and is one of the most important parts of a large civil passenger plane. The aero-engine fan blade with the large bypass ratio rotates at a high speed in the fan casing, and under the action of foreign object impact or self internal defects, once the fan blade fails (such as breaking and flying out), the fan casing is required to be capable of effectively containing fragments of the failed fan blade, otherwise the fragments are likely to rush out of the engine, penetrate through the casing, further enlarge the damage of the engine, even break through an oil tank, damage a fuselage or break through an airplane, and further cause catastrophic results. From the perspective of economy and efficiency, the fan casing is also required to reduce the weight of the fan casing on the basis of meeting the inclusion, so that the weight of the whole engine is reduced, the fuel consumption is reduced, the thrust-weight ratio is improved, and the economy and the competitiveness of the engine are improved.

Although the fan case goes through three stages of an all-metal case, a partially composite case, and a fully composite case, there is no targeted design for blade capture, and due to its stringent weight reduction requirements, further improvement in the structural efficiency of the case against ballistic impact is needed.

Aiming at the requirements of the containment of the trapping characteristics and weight reduction of the casing, a trapping type ballistic impact resistant composite material fan casing and a manufacturing method thereof are needed urgently to improve the structural efficiency of the casing for ballistic impact resistance and solve the problem of the trapping containment of blade fracture.

Disclosure of Invention

Aiming at the contained casing of the fan of the aero-engine, according to the damage mode and the structural efficiency of the contained casing, a contained structure is divided into five layers, namely a compression-resistant shear layer, a tensile layer, a fence layer consisting of high-toughness metal, an energy absorbing layer and an anti-deformation layer, wherein each layer has unique ballistic impact characteristics.

The technical scheme provided by the invention is as follows:

the fan casing is of a revolving body structure and comprises two flange areas, two uncontained areas and a contained area, wherein the flange areas are located at two ends of the fan casing, the thickness of the flange areas is 12-17 mm, and the maximum outer diameter is set according to the pneumatic design requirement of an aeroengine; the non-containing area is arranged between the containing area and the flange area, and the thickness of the non-containing area is 12-17 mm; the flange region is located in the middle of the fan casing and is a variable thickness region gradually thickened from two ends to the middle, the maximum thickness of the middle is 28-35 mm, and the flange region is of a multi-phase structure correspondingly selected according to damage modes of different stages of high-speed impact.

In a second aspect, a method for manufacturing a captured ballistic impact resistant composite fan case includes the steps of:

step 1, paving a 1-2 mm environment protection layer on the whole fan casing die, wherein the environment protection layer is a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg and is used for forming a flange area and an uncontained area;

step 2, paving a pressure-resistant shear layer of the passivated elastomer in the range of the corresponding containing area on the fan case die, and sucking and compacting the glue;

step 3, paving prepreg in a range corresponding to the whole fan case on a fan case die, forming a tensile layer in a range corresponding to a containing region, and forming a flange region and a non-containing region together with an environment protection layer outside the range corresponding to the containing region;

step 4, paving a fence layer and an energy absorption layer in the range of the corresponding containing area on the fan case mould, and performing glue absorption and compaction;

step 5, paving a 1-5 mm environment protection layer on the whole fan casing die, wherein the environment protection layer is a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg and is used for forming a flange area and an uncontaining area;

step 6, curing the paved material, performing size measurement and nondestructive testing after demolding and cleaning, and performing machining according to the specification after the testing requirements are met;

and 7, anodizing the split aluminum alloy panel by adopting a medium-temperature adhesive film, and then bonding and curing the aluminum alloy panel in a containing area.

According to the capture type ballistic impact resistant composite material fan case and the manufacturing method thereof provided by the invention, the following beneficial effects are achieved:

(1) the invention provides a capture type ballistic impact resistant composite material fan case and a manufacturing method thereof, aiming at the fan case of an aero-engine, a containing structure is divided into five layers according to the damage mode and the structural efficiency of the fan case, each layer has unique ballistic impact characteristics, the structural efficiency of the case for resisting ballistic impact is improved, and the capture and containing problems of blade fracture are solved;

(2) compared with other structures, the capture type ballistic impact resistant composite material fan case provided by the invention is easier to capture high-speed projectiles instead of rebound, penetration or large-area failure, is beneficial to controlling primary and secondary damage, and enhances the structural reliability.

Drawings

FIG. 1 illustrates a schematic cross-sectional view of a captured ballistic impact resistant composite fan case of the present invention;

FIG. 2 shows a curing schedule for the composite fan case of examples 1 and 2.

Description of the reference numerals

1-containing region, 2-flange region, 3-non-containing region.

Detailed Description

The features and advantages of the present invention will become more apparent and appreciated from the following detailed description of the invention.

According to a first aspect of the invention, a captured ballistic impact resistant composite material fan casing is provided, as shown in fig. 1, the fan casing is of a revolving body structure and comprises two flange regions 2, two non-containing regions 3 and a containing region 1, wherein the flange regions 2 are located at two ends of the fan casing, the thickness of the flange regions is 12-17 mm, and the maximum outer diameter is set according to the aerodynamic design requirement of an aeroengine and is used as a connecting part to be connected with an external structure; the non-containing region 3 is arranged between the variable thickness containing region 1 and the flange region 2, the thickness is 12-17 mm, and the function of transition connection is achieved; the flange region 2 is located in the middle of the fan casing and is a variable thickness region gradually thickened from two ends to the middle, the maximum thickness of the middle is 28-35 mm, and the flange region 2 is a multi-phase structure correspondingly selected according to the damage modes of different stages of high-speed impact and is an impact region mainly used for resisting blade fracture.

In the invention, the flange region 2 is formed by curing a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg.

The high-modulus carbon fiber reinforced high-tenacity epoxy resin prepreg can be selected from one or a combination of unidirectional tapes of M40J or M55J or twill weaves thereof. The selection strategy of the prepreg is mainly based on the adopted process method, if the prepreg is a unidirectional tape, the prepreg is realized by adopting an automatic filament paving mode (the width of a single tape is 6.35mm), the number of the filament bundles can be single filament bundles, 4 filament bundles and 8 filament bundles, and the angle is +/-60/0; if the fabric is twill fabric, the winding mode is adopted.

In a preferred embodiment of the invention, the junction between the flange region 2 and the non-containment region 3 forms a rounded corner (R-corner), both the inner R-corner and the outer R-corner being R5-R20, preferably R5.

In a preferred embodiment of the present invention, the circumferential flange surface of the flange region 2 is uniformly provided with e.g. 100 connecting through holesAnd a plurality of error-proof holes, e.g. 3The error-protection hole of (1).

In the invention, the non-containing region 3 is formed by curing a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg, and preferably, the thickness and the laying mode are both consistent with those of the flange region 2.

In the invention, the containing region 1 comprises a pressure shear resistant layer, a tensile layer, a fence layer, an energy absorbing layer and an anti-deformation layer from the inside to the outside of the flow passage surface, and the light capture type ballistic impact resistant composite material is formed by composite materials with corresponding performance requirements according to a proportion.

In the containing region 1, the compression-shear resistant layer can be made of a high-modulus carbon fiber reinforced composite material or an aramid fiber reinforced composite material, the tensile modulus of high-modulus carbon fibers in the high-modulus carbon fiber reinforced composite material needs to be more than 350GPa, and the tensile strength of aramid fibers in the aramid fiber reinforced composite material needs to be more than 4.2 GPa. The compression shear resistant layer acts to passivate the projectile, to deform the projectile by interacting with the projectile to dissipate energy and to capture it, and to convert the load into a face load by fabric design, reducing the probability of penetration.

Preferably, for the high-modulus carbon fiber reinforced composite material, the fabric design mode is satin fabric; aiming at the aramid fiber reinforced composite material, the fabric design mode is satin fabric.

Preferably, in order to deal with the flying-off of the fan blade, the proportion of the anti-pressure shear layer in the containing region is between 17 and 20 weight percent.

In the containing region 1, the tensile layer may be made of a high-strength carbon fiber reinforced composite material, and the tensile strength of the high-strength carbon fibers in the high-strength carbon fiber reinforced composite material needs to be greater than 5.5GPa, including but not limited to T800H, T1000G, and the like. The tensile layer is mainly used for coping with the failure mode mainly based on stretching at the current moment, further dispersing energy and slowing down the inertia of the first compression-shear resistant layer in fracture. Preferably, the proportion of the tensile layer in the containing area is between 17 wt% and 33 wt%.

In the containing area 1, the fence layer is an adhesive film containing a metal net, and the peeling strength of the roller is required to be more than 40N/25 mm. Preferably, the proportion of the fence layer in the containment zone is between 2 wt% and 3 wt%.

In the containing region 1, the energy absorption layer can be made of a small-tow aramid fiber satin fabric reinforced composite material or a small-tow aramid fiber cloth and an epoxy resin composition with the mass fraction of 20-40%, wherein the linear density of aramid fibers is less than 40 tex. The energy absorbing layer is mainly used to absorb a large amount of energy by the fracture strain of the composite material. Preferably, the ratio of the energy absorption layer in the containing region is between 17 wt% and 25 wt%.

In the containing region 1, the deformation-preventing layer is usually a metal alloy backboard, preferably a metal aluminum alloy backboard, the tensile strength is required to be greater than 350MPa, the main function is to limit the total deformation of the front four layers, and the phenomenon that the deformation caused after ballistic impact is too large to interfere with the assembly relation of related parts is prevented. Preferably, the thickness of the deformation prevention layer is 1-1.5 mm.

In a preferred embodiment of the invention, the containing region 1 is a variable thickness region, and is realized by changing the laying range of the pressure shear resistant layer, the tensile layer, the fence layer, the energy absorbing layer and the deformation preventing layer, and the region corresponding to the flying-off blade capturing region in the containing region has the pressure shear resistant layer, the tensile layer, the fence layer, the energy absorbing layer and the deformation preventing layer.

In a preferred embodiment of the invention, except for the deformation-preventing layer, when the types of fibers in the composite materials selected between the adjacent two layers of the compression-resistant shear layer, the tensile layer, the fence layer and the energy absorption layer are different, a transition layer of 1 mm-3 mm can be arranged between the adjacent two layers, the transition layer is a mixed fiber reinforced composite material, and the mixed fiber is a fiber used in the composite materials of the adjacent two layers, so as to meet the requirement of rigidity matching.

Furthermore, the transition layer is a gradient mixed-woven fiber reinforced composite material, the proportion of the used fibers is gradually changed in the interlayer direction, and the fibers in the transition layer are changed from single fibers on one side into mixed-woven fibers and then into single fibers on the other side.

According to a second aspect of the present invention, there is provided a method for manufacturing a captive ballistic impact resistant composite fan case, for preparing the captive ballistic impact resistant composite fan case according to the first aspect, comprising the steps of:

step 1, paving a 1-2 mm environment protection layer on the whole fan casing die, wherein the environment protection layer is a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg and is used for forming a flange area and an uncontained area;

step 2, paving a pressure-resistant shear layer of the passivated elastomer in the range of the corresponding containing area on the fan case die, and sucking and compacting the glue;

step 3, paving prepreg in a range corresponding to the whole fan case on a fan case die, forming a tensile layer in a range corresponding to a containing region, and forming a flange region and a non-containing region together with an environment protection layer outside the range corresponding to the containing region;

step 4, paving a fence layer and an energy absorption layer in the range of the corresponding containing area on the fan case mould, and performing glue absorption and compaction;

step 5, paving a 1-5 mm environment protection layer on the whole fan casing die, wherein the environment protection layer is a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg and is used for forming a flange area and an uncontaining area;

step 6, curing the paved material, performing size measurement and nondestructive testing after demolding and cleaning, and performing machining according to the specification after the testing requirements are met;

and 7, anodizing the split aluminum alloy panel by adopting a medium-temperature adhesive film, and then bonding and curing the aluminum alloy panel in a containing area.

In the present invention, the materials and thicknesses of the compression-resistant layer, the tensile layer, the fence layer, the energy absorbing layer and the deformation-resistant layer are the same as those of the first aspect, and thus, the detailed description thereof is omitted.

In the invention, if the fiber types of the composite materials selected between the adjacent two layers of the pressure shear resistant layer, the tensile layer, the fence layer and the energy absorption layer are different, a transition layer of 1-3 mm can be arranged between the adjacent two layers, the transition layer is a mixed fiber reinforced composite material, and the mixed fiber is a fiber used in the composite materials of the adjacent two layers so as to meet the requirement of rigidity matching.

Examples

Example 1

a) The whole 2mm environment protection layer of the casing is paved by adopting automatic filament paving (the bandwidth of a single filament is 6.35mm), the number of the filament bundles is 8, the angle is selected to be +/-60/0, and the adopted material is M40J/603B high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg;

b) in the containing region, an aramid prepreg (F-8H3/603B) with the thickness of 5mm is laid and covered automatically to serve as a compression-resistant shearing layer;

c) sucking and compacting the glue;

d) adopting aramid fiber and carbon fiber mixed prepreg (F-T800/603B) as a transition layer to wind and cover 2mm in a containing region; the proportion of the fibers used in the transition layer is gradually changed in the interlayer direction, and the fibers in the transition layer are changed into the mixed fiber from the single fiber on one side and then into the single fiber on the other side;

e) adopting M40J/603B high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg in the integral area of the casing, and automatically laying wires to form a tensile layer with the thickness of 5 mm;

f) covering AF535XS metal net film with thickness of 1mm in the containing region;

g) adopting aramid fiber and carbon fiber mixed prepreg (F-T800/603B) as a transition layer to wind and cover 2mm in a containing region; the proportion of the fibers used in the transition layer is gradually changed in the interlayer direction, and the fibers in the transition layer are changed into the mixed fiber from the single fiber on one side and then into the single fiber on the other side;

h) an aramid prepreg (F-8H3/603B) with the thickness of 5mm is paved and covered in the containing area automatically to be used as an energy absorbing layer;

i) sucking and compacting the glue;

j) adopting M40J/603B high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg in the integral area of the casing, and automatically laying or winding to form an environment protection layer by 5 mm;

k) the casing is cured by adopting a curing system as shown in figure 2, the heating rate is 20 +/-5 ℃/h, the temperature is kept at 180 ℃ for 4 hours, the cooling rate is less than or equal to 30 ℃, the machine is stopped at 80 ℃, the door is opened, the temperature is reduced, the casing is taken out when the temperature is less than or equal to 50 ℃, and the curing and heat-preserving time can be properly shortened as required;

l) dimensional measurement and non-destructive testing

After the product is cured, demoulded and cleaned, size measurement and ultrasonic nondestructive detection are carried out;

the nondestructive testing method comprises the following steps: DqES219-88 ultrasonic flaw detection method for carbon epoxy composite material;

m) machining

And processing the upper end face and the lower end face, the thickened area and the like according to the requirements of a drawing.

n) adopting a J-47 adhesive film, anodizing the 1mm aluminum alloy panel divided into three sections, and then bonding and curing in a containing area, wherein the curing system is as follows:

the curing pressure is (0.30 +/-0.02) MPa. Heating to 130 +/-5 ℃ from room temperature at the heating speed of 2-4 ℃/min (the temperature is the temperature of the test piece), keeping the temperature for 3h, stopping heating, and naturally cooling the test piece to below 60 ℃ under the pressure. In the containing area of the prepared fan case, the proportion of the compression-resistant shear layer is 18.5 wt%, the proportion of the tensile layer is 18.5 wt%, the proportion of the fence layer is 2.8 wt%, the proportion of the energy-absorbing layer is 21.2 wt%, and the proportion of the deformation-preventing layer is 6.0 wt%. The average thickness of the two flange regions and the two non-containing regions is 12mm, an angle R is formed at the joint of the flange regions and the non-containing regions, and the inner angle R and the outer angle R are both R5.

Example 2

a) Paving an environment protection layer of 2mm of the whole casing, and winding, wherein the material M40J-XW/603B is a high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg, and the number of fiber tows is single tows;

b) paving 5mm aramid prepreg (F-8H3/603B) as a compression-resistant shear layer in a wrapping mode in a containing region;

c) sucking and compacting the glue;

d) adopting aramid fiber and carbon fiber mixed prepreg (F-T800/603B) as a transition layer to wind and cover 2mm in a containing region; the proportion of the fibers used in the transition layer is gradually changed in the interlayer direction, and the fibers in the transition layer are changed into the mixed fiber from the single fiber on one side and then into the single fiber on the other side;

e) adopting M40J-XW/603B high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg in the integral area of the casing, and winding and forming a tensile layer by 5 mm;

f) covering AF535XS metal-containing net glue film on the containing region;

g) adopting aramid fiber and carbon fiber mixed prepreg (F-T800/603B) as a transition layer to wind and cover 2mm in a containing region; the proportion of the fibers used in the transition layer is gradually changed in the interlayer direction, and the fibers in the transition layer are changed into the mixed fiber from the single fiber on one side and then into the single fiber on the other side;

h) paving 5mm aramid prepreg (F-8H3/603B) as an energy absorption layer in a winding manner in the containing region;

i) sucking and compacting the glue;

j) an M40J-XW/603B high-modulus carbon fiber reinforced high-toughness epoxy resin prepreg is adopted in the integral area of the casing, and an environment protection layer is wound and molded by 5 mm;

k) the casing is solidified by adopting a solidification system as shown in figure 2, the temperature rise rate is 20 +/-5 ℃/h, the temperature is kept at 180 ℃ for 4 hours, the temperature reduction rate is less than or equal to 30 ℃, the machine is stopped at 80 ℃, the door is opened, the temperature is reduced, the casing is taken out when the temperature is less than or equal to 50 ℃, and the solidification and heat preservation time can be properly shortened according to the requirement.

l) after the product is cured, demoulded and cleaned, carrying out size measurement and ultrasonic nondestructive testing. The nondestructive testing method comprises the following steps: DqES219-88 ultrasonic flaw detection method for carbon epoxy composite material;

m) processing the upper end face and the lower end face, a thickening area and the like according to the requirements of a drawing;

n) adopting a J-154 adhesive film, anodizing the 1mm aluminum alloy panel divided into three sections, and then bonding and curing in a containing area, wherein the curing system is as follows:

the curing pressure is (0.30 +/-0.02) MPa. Heating to 130 +/-5 ℃ from room temperature at the heating speed of 2-4 ℃/min (the temperature is the temperature of the test piece), keeping the temperature for 3h, stopping heating, and naturally cooling the test piece to below 60 ℃ under the pressure. In the containing area of the prepared fan case, the proportion of the compression-resistant shear layer is 18.5 wt%, the proportion of the tensile layer is 18.5 wt%, the proportion of the fence layer is 2.8 wt%, the proportion of the energy-absorbing layer is 21.2 wt%, and the proportion of the deformation-preventing layer is 6.0 wt%. The average thickness of the two flange regions and the two non-containing regions is 12mm, an angle R is formed at the joint of the flange regions and the non-containing regions, and the inner angle R and the outer angle R are both R5.

The invention has been described in detail with reference to specific embodiments and illustrative examples, but the description is not intended to be construed in a limiting sense. Those skilled in the art will appreciate that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, which fall within the scope of the present invention. The scope of the invention is defined by the appended claims.