Reference block for detecting debonding defect of composite material wing and manufacturing method of reference block

Abstract

The invention provides a reference block for detecting a debonding defect of a composite wing and a manufacturing method, the reference block is of a cube structure and comprises a composite skin and a foam sandwich block, the composite skin and the foam sandwich block are connected through an adhesive film layer, and the adhesive film layer is arranged between the composite skin and the foam sandwich block. A plurality of polytetrafluoroethylene film wafers I with different diameters are tightly connected between the composite material skin and the adhesive film layer; a plurality of polytetrafluoroethylene film wafers II with different diameters are tightly connected between the foam sandwich block and the adhesive film layer; according to the method, the precision and the sensitivity of ultrasonic detection equipment during detection of the composite material wing body can be ensured, so that the recognition accuracy of ultrasonic detection on the internal debonding defect of the carbon fiber composite material wing body is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of non-destructive testing of composite structural parts, and particularly to a reference block for detecting debonding defects of a composite wing and a manufacturing method thereof. Background Art

[0002] Carbon fiber reinforced polymer (CFRP) has been widely used in aircraft structural parts in the aerospace field, especially in the wing part, due to its excellent strength-to-weight ratio and outstanding fatigue resistance. When designing a CFRP wing, a skin-core structure is often adopted to reduce weight. However, during the product processing of this structure, voids are likely to form between the CFRP skin (1) and the core material, resulting in bonding failure and debonding defects, which greatly affect its mechanical properties and may even cause the wing of the aircraft to break and crash in extreme cases.

[0003] Since the appearance color of the CFRP wing is relatively dark, it is difficult to visually inspect the internal quality of the product effectively. Therefore, methods such as ultrasonic, tapping or ray are usually used to identify and judge internal defects. Considering economy, convenience and accuracy comprehensively, ultrasonic testing is often the preferred option. During ultrasonic testing, the accuracy and sensitivity of the testing equipment are crucial for the testing results. To ensure the accuracy of ultrasonic testing, a reference block is usually made before testing.

[0004] A reference block refers to a test block containing simulated defects, which is mainly used for testing system adjustment, recheck and defect evaluation; for the production of a reference standard, its raw materials, layup and surface state should be the same as those of the part to be inspected, and it is required to be detected with a sensitivity one level higher than the acceptance level to ensure that there are no natural defects affecting its use in the reference block. This involves pre-embedding artificial simulated debonding defects between the skin and the core material of the CFRP wing to make a reference block, and then using the reference block to calibrate the testing equipment. In this way, the accuracy and sensitivity of the testing equipment are ensured, and further the recognition accuracy of internal debonding defects in the CFRP wing is improved.

[0005] The invention with the application number CN201811431663.3 discloses an ultrasonic reference block for detecting thick carbon fiber composite materials. This ultrasonic reference block includes a body, and the upper surface of the body includes planes located at different horizontal levels, and two first delamination defects and second delamination defects with different diameters are preset inside corresponding to each plane. Use an ultrasonic testing device to detect the two delamination defects on different planes of this ultrasonic reference block, and adjust the gain after finding the defects to make the reflected wave amplitude reach 80% of the full screen, save the gain value, and finally directly generate a TVG curve by setting parameters in the ultrasonic testing device, so as to efficiently detect the recorded defects and reject defects in thick carbon fiber composite materials.

[0006] In the invention with the application number CN202110962963.X, a method for manufacturing a reference block for detecting delamination defects in a composite laminate structure is disclosed, such as designing a drawing of the reference block according to the object to be inspected; cutting a polytetrafluoroethylene film according to the delamination size of the object to be inspected; manufacturing a positioning plate according to the designed drawing, and the positioning plate is provided with openings corresponding to flat-bottomed holes; laying prepreg according to the designed drawing, and fixing the polytetrafluoroethylene film at the laying surface through the positioning plate; curing the reference block and drilling with a drill bit to the position of the polytetrafluoroethylene film. It has the technical effect of ensuring that the deepest part of the drilling is between layers, thereby realizing the precise positioning of artificial delamination defects in the depth direction.

[0007] These two types of reference blocks can be well detected and applied for detecting delamination defects inside carbon fiber composite materials, but it is difficult to apply them to the detection of debonding defects of carbon fiber composite wings. Because the skin and sandwich material of carbon fiber composite wings are often bonded with a film, neither of the above two types of reference blocks has this film-containing structural form, nor is it a manufacturing method of a reference block for artificially simulating debonding defects. Summary of the Invention

[0008] The purpose of the present invention is to provide a reference block and a manufacturing method for detecting debonding defects of a composite wing, which can ensure the accuracy and sensitivity of an ultrasonic detection device when detecting a composite wing, and further improve the recognition accuracy of ultrasonic detection for debonding defects inside a carbon fiber composite wing.

[0009] To achieve the above purpose, the present invention is realized through the following technical solutions:

[0010] A reference block for detecting debonding defects of a composite wing, the reference block has a cube structure, including a composite skin and a foam core block, the composite skin and the foam core block are connected through a film layer, and a plurality of polytetrafluoroethylene film discs with different diameters are closely connected between the composite skin and the film layer; a plurality of polytetrafluoroethylene film discs with different diameters are closely connected between the foam core block and the film layer.

[0011] Further, a plurality of polytetrafluoroethylene film discs with different diameters are used to simulate debonding defects of different sizes between the composite skin and the film layer; a plurality of polytetrafluoroethylene film discs with different diameters are used to simulate debonding defects of different sizes between the film layer and the foam core block; the composite skin is a carbon fiber composite skin.

[0012] Further, there is no overlap between a plurality of polytetrafluoroethylene film discs with different diameters and a plurality of polytetrafluoroethylene film discs with different diameters.

[0013] Further, a plurality of polytetrafluoroethylene film discs I with different diameters and a plurality of polytetrafluoroethylene film discs II with different diameters are respectively located on both sides of the central section of the comparison test block; the extending direction of the central section is parallel to the extending direction of the axis lines of the polytetrafluoroethylene film discs I and the polytetrafluoroethylene film discs II.

[0014] Further, the centers of the same cross-section of the plurality of polytetrafluoroethylene film discs I with different diameters are on the same straight line, and the diameters of the plurality of polytetrafluoroethylene film discs I with different diameters increase successively along this straight line direction;

[0015] The centers of the same cross-section of the plurality of polytetrafluoroethylene film discs II with different diameters are on the same straight line, and the diameters of the plurality of polytetrafluoroethylene film discs II with different diameters increase successively along this straight line direction.

[0016] Further, four polytetrafluoroethylene film discs I with different diameters are tightly connected between the composite skin and the adhesive film layer, and the diameters of the four polytetrafluoroethylene film discs I with different diameters are respectively

[0017] Four polytetrafluoroethylene film discs II with different diameters are tightly connected between the foam core block and the adhesive film layer, and the diameters of the four polytetrafluoroethylene film discs II with different diameters are respectively

[0018] Further, the length of the comparison test block is 300 - 310 mm, and the width is 300 - 310 mm.

[0019] As a general inventive concept, the present invention provides a method for manufacturing a comparison test block for detecting debonding defects of a composite material wing, including the following steps:

[0020] S1. Use a cutting machine to cut the carbon fiber prepreg and the glass fiber prepreg, and place the cut prepregs in order and in sets;

[0021] S2. The laying operation is carried out on a working platform, and the outer shape dimension lines and the ply direction angle lines are marked on the platform; wipe the working platform and the mold clean, and lay a release cloth on the mold, and the release cloth is closely attached to the surface of the mold;

[0022] S3. Dry the foam core block material;

[0023] S4. Lay the glass fiber prepreg, multiple layers of unidirectional carbon fiber prepregs, and the glass fiber prepreg in sequence according to the numbers; during the laying process, pre-compact once every 6 layers of prepregs under vacuum conditions;

[0024] S5. After the prepreg is laid, apply a medium-temperature curing adhesive film on the outermost layer of the prepreg. On the side of the medium-temperature curing adhesive film that adheres to the prepreg, closely attach a plurality of polytetrafluoroethylene film discs with different diameters in advance; gently press by hand to make the medium-temperature curing adhesive film adhere tightly to the prepreg; on the other side of the medium-temperature curing adhesive film that adheres to the prepreg, also closely attach a plurality of polytetrafluoroethylene film discs with different diameters, and then take a foam core block material piece and attach it to the medium-temperature curing adhesive film to make a contrast test block preform;

[0025] S6. Place the mold containing the contrast test block preform into a press, apply contact pressure until the heating platform contacts the mold;

[0026] S7. Heat up at a heating rate not greater than 3 °C / min to 80 - 85 °C, and keep warm for 30 - 35 min; apply pressure until the mold is closed, use a feeler gauge to detect the gap, and require the closing gap to be not greater than 0.1 mm; heat up at a heating rate not greater than 3 °C / min to 120 - 130 °C, and keep warm and under pressure for 90 - 110 min; under the condition of keeping pressure, cool down at a cooling rate not greater than 2 °C / min or naturally cool to below 60 °C to relieve pressure, and open the mold to take out the contrast test block molded part;

[0027] S8. Process the contrast test block molded part according to the predetermined size;

[0028] S9. After processing, promptly remove the moisture from the contrast test block;

[0029] S10. Conduct ultrasonic testing on the manufactured contrast test block and conduct acceptance.

[0030] Further, in step S4, the laying angle of the unidirectional carbon fiber prepreg is 0°, +45° or -45°, and the laying angle of the glass fiber prepreg is ±45°;

[0031] When laying the prepreg, lay it layer by layer, detect layer by layer, and record layer by layer; the prepreg should be kept flat and completely closely adhered to the previous layer of prepreg; the time for pre-compaction is 15 - 18 min, and the vacuum pressure is not greater than -0.094 MPa.

[0032] Further, in step S1, start the cutting machine to cut the prepreg into several pieces with a length * width of 320 mm * 320 mm; in step S7, open the mold to take out the contrast test block molded part with a length * width of 320 mm * 320 mm; in step S8, process the contrast test block molded part according to the size of length * width of 300 mm * 300 mm.

[0033] The beneficial effects of the present invention are:

[0034] In order to make up for the lack of the contrast test block scheme for debonding defects of composite material wing bodies in the existing technology, a contrast test block scheme is designed in which a film adhesive is used between the skin and the sandwich material of the composite material wing body at a specific thickness, and polytetrafluoroethylene film discs are embedded to simulate debonding defects. A manufacturing method for this contrast test block scheme is provided to ensure the accuracy and sensitivity of the ultrasonic testing equipment when detecting composite material wing bodies, thereby improving the recognition accuracy of ultrasonic testing for internal debonding defects of carbon fiber composite material wing bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained as these drawings.

[0036] Figure 1 It is a schematic structural diagram of the contrast test block in Embodiment 1 of the present invention;

[0037] Figure 2 It is a distribution diagram of the first polytetrafluoroethylene film disc and the second polytetrafluoroethylene film disc on the preformed contrast test block in Embodiment 1 of the present invention;

[0038] In the figure: 1. Composite material skin; 2. Foam sandwich block; 3. Adhesive film layer; 4. First polytetrafluoroethylene film disc; 5. Second polytetrafluoroethylene film disc. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0040] Embodiment 1:

[0041] A contrast test block for detecting debonding defects of a composite material wing. The contrast test block has a cube structure, as Figure 1 shown, including a composite material skin 1 and a foam sandwich block 2. The composite material skin 1 and the foam sandwich block 2 are connected through an adhesive film layer 3. A plurality of first polytetrafluoroethylene film discs 4 with different diameters are tightly connected between the composite material skin 1 and the adhesive film layer 3; a plurality of second polytetrafluoroethylene film discs 5 with different diameters are tightly connected between the foam sandwich block 2 and the adhesive film layer 3.

[0042] In this embodiment, a plurality of polytetrafluoroethylene film discs 1 with different diameters are used to simulate the debonding defects of composite skins 1 and adhesive film layers 3 of different sizes; a plurality of polytetrafluoroethylene film discs 2 with different diameters are used to simulate the debonding defects of the adhesive film layer 3 and the foam core block 2 of different sizes. The composite skin is a carbon fiber composite skin.

[0043] In this embodiment, there is no overlap between the plurality of polytetrafluoroethylene film discs 1 with different diameters and the plurality of polytetrafluoroethylene film discs 2 with different diameters.

[0044] In this embodiment, the plurality of polytetrafluoroethylene film discs 1 with different diameters and the plurality of polytetrafluoroethylene film discs 2 with different diameters are respectively located on both sides of the central section of the reference specimen; the extending direction of this central section is parallel to the extending direction of the axis lines of the polytetrafluoroethylene film discs 1 and the polytetrafluoroethylene film discs 2.

[0045] In this embodiment, the centers of the same section of the plurality of polytetrafluoroethylene film discs 1 with different diameters are on the same straight line, and the diameters of the plurality of polytetrafluoroethylene film discs 1 with different diameters increase sequentially along this straight line direction;

[0046] The centers of the same section of the plurality of polytetrafluoroethylene film discs 2 with different diameters are on the same straight line, and the diameters of the plurality of polytetrafluoroethylene film discs 2 with different diameters increase sequentially along this straight line direction.

[0047] In this embodiment, the straight line where the centers of the same section of the plurality of polytetrafluoroethylene film discs 1 with different diameters are located and the straight line where the centers of the same section of the plurality of polytetrafluoroethylene film discs 2 with different diameters are located are both parallel to the central section.

[0048] In this embodiment, the length of the reference specimen is 300 mm and the width is 300 mm;

[0049] Specifically, four polytetrafluoroethylene film discs 1 with different diameters are tightly connected between the composite skin 1 and the adhesive film layer 3, and the diameters of the four polytetrafluoroethylene film discs 1 with different diameters are respectively

[0050] Four polytetrafluoroethylene film discs 2 with different diameters are tightly connected between the foam core block 2 and the adhesive film layer 3, and the diameters of the four polytetrafluoroethylene film discs 2 with different diameters are respectively

[0051] In this embodiment, the method for manufacturing the reference specimen for detecting the debonding defect of the composite wing includes the following steps:

[0052] S1. Flatten and fix the carbon fiber prepreg and glass fiber prepreg on the cutting machine table. After the prepreg to be cut is adsorbed on the adsorption table of the cutting machine, start the cutting machine to cut the prepreg into several pieces with a length * width of 320 mm * 320 mm. The angular deviation of the prepreg fiber direction is controlled within ±2°. The cut prepregs are placed in order for subsequent laying and use.

[0053] S2. The laying operation is carried out on the working platform. The outer contour dimension line and ply direction angle line of the laying are marked on the platform; use a lint-free cloth dipped in alcohol to wipe the working table and the mold clean, and lay a release cloth on the mold. The release cloth is closely attached to the surface of the mold.

[0054] S3. Dry the foam core block material to prevent shrinkage during the curing process, and machine-process the surface of the foam core material to ensure the foam strength performance.

[0055] S4. Lay the glass fiber prepreg, 16 layers of unidirectional carbon fiber prepreg, and glass fiber prepreg in sequence according to the numbering order of the cutting diagram (Appendix 1); during laying, lay layer by layer, detect layer by layer, and record layer by layer; keep it flat and closely fit with the previous layer completely, and there shall be no "bridging, folding, air entrapment, inclusion". The released separator paper shall be checked according to the number of laying layers and placed neatly on one side to prevent it from being brought into the laying layer. When it is necessary to cut the prepreg, a backing plate shall be placed under the prepreg to be cut to prevent scratching other prepreg cloth layers;

[0056] During the laying process, pre-compact once every 6 layers of prepreg under vacuum conditions; the pre-compaction time is 15 min, and the vacuum pressure is not greater than -0.094 MPa.

[0057] S5. After the prepreg laying is completed, stick a medium-temperature curing adhesive film on the outermost layer of the prepreg. On the side of the medium-temperature curing adhesive film adhered to the prepreg, four polytetrafluoroethylene film discs 4 with diameters of are pre-adhered (for the specific pasting positions, see Appendix Figure 2 ). Gently press by hand to make the medium-temperature curing adhesive film closely adhere to the prepreg;

[0058] On the other side of the medium-temperature curing adhesive film adhered to the prepreg, four polytetrafluoroethylene film discs 5 with diameters of are also closely adhered (for the specific pasting positions, see Appendix Figure 2 ). Then take a foam core block 2 material block and stick it on the medium-temperature curing adhesive film to make a contrast test block preform.

[0059] S6. Place the mold containing the contrast test block preform into the press, apply contact pressure until the heating platform contacts the mold.

[0060] S7. Heat up at a heating rate not greater than 3 °C / min to 80 °C and keep warm for 32 min; apply pressure until the mold is closed, and use a feeler gauge to detect the gap, requiring that the closing gap is not greater than 0.1 mm; heat up at a heating rate not greater than 3 °C / min to 125 °C and keep warm and under pressure for 100 min; under the condition of keeping pressure, cool down at a cooling rate not greater than 2 °C / min or cool naturally to below 60 °C to relieve pressure, and open the mold to take out the compression molded part of the comparison test block with a length * width of 320 mm * 320 mm.

[0061] S8. Turn on the machining equipment, set the machining program of the sample in the computer software, confirm that the machining equipment is running well, place the compression molded part of the cured comparison test block on the machining platform of the machining equipment and use a fixture to clamp both ends of the sample and fix it; adjust the tool position of the machining equipment according to the position of the compression molded part of the comparison test block to be machined; import the machining program set on the computer and machine the compression molded part of the comparison test block according to the size of length * width of 300 mm * 300 mm, and use tap water for cooling during machining.

[0062] S9. After machining, promptly remove the moisture of the comparison test block.

[0063] S10. Conduct ultrasonic non-destructive testing on the fabricated comparison test block, fill in the corresponding records, and issue an ultrasonic testing report.

[0064] S11. Accept the test block. To pass the acceptance, the following requirements need to be met: a) The difference between the detected defect size and the actual embedded artificial defect area does not exceed ±25%; b) There should be no delamination, dispersion, porosity, debonding, inclusion or natural defects affecting the evaluation and analysis on the comparison test block; c) The appearance of the comparison test block should have no foreign matters such as edge delamination, damage, bulging, wrinkling or overflowing glue that affect the detection.

[0065] S12: Paste the comparison test block identification on the test block that passes the acceptance. For the convenience of distinction and identification, adopt the representation method of "xx - xx - xx - xx" recommended by HB7825 - 2007 "Manufacture and Requirements of Non-destructive Testing Comparison Test Blocks for Composite Parts", where "xx" represents the product code, the English abbreviation of the testing method, the composite material structure type, and the test block serial number in sequence from left to right. For example, the number of "the 1st carbon fiber composite laminate comparison test block for wing body ultrasonic testing" is "Y1 - UT - 01 - 01".

[0066] S12: Conduct regular identification on the comparison test block every year, and execute according to the acceptance requirements. It can continue to be used only when the acceptance requirements are met.

[0067] Appendix 1:

[0068]

[0069]

[0070] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A comparative test block for composite wing debonding defect detection, characterized in that: The comparison test block has a cubic structure, including a composite material skin and a foam sandwich block, wherein the composite material skin and the foam sandwich block are connected by a film layer, and a plurality of polytetrafluoroethylene film discs with different diameters are tightly connected between the composite material skin and the film layer; a plurality of polytetrafluoroethylene film discs with different diameters are tightly connected between the foam sandwich block and the film layer.

2. The comparative test block for composite wing debonding defect detection according to claim 1, characterized in that: A plurality of polytetrafluoroethylene film discs with different diameters are used to simulate debonding defects between composite material skins and film layers of different sizes; a plurality of polytetrafluoroethylene film discs with different diameters are used to simulate debonding defects between film layers and foam sandwich blocks of different sizes; the composite material skin is a carbon fiber composite material skin.

3. The comparative test block for composite wing debonding defect detection according to claim 1, characterized in that: There is no overlap between the first polytetrafluoroethylene membrane discs with different diameters and the second polytetrafluoroethylene membrane discs with different diameters.

4. The comparative test block for composite wing debonding defect detection according to any one of claims 1 to 3, characterized in that: A plurality of polytetrafluoroethylene membrane discs 1 with different diameters and a plurality of polytetrafluoroethylene membrane discs 2 with different diameters are respectively located on both sides of the central section of the comparison test block; the extension direction of the central section is parallel to the extension direction of the axis of the polytetrafluoroethylene membrane disc 1 and the polytetrafluoroethylene membrane disc 2.

5. The comparative test block for composite wing debonding defect detection according to any one of claims 1 to 3, characterized in that: The centers of the same cross section of the plurality of polytetrafluoroethylene membrane discs with different diameters are on the same straight line, and the diameters of the plurality of polytetrafluoroethylene membrane discs with different diameters increase successively along the straight line; The centers of the same cross section of the multiple polytetrafluoroethylene membrane discs 2 with different diameters are on the same straight line, and the diameters of the multiple polytetrafluoroethylene membrane discs 2 with different diameters increase successively along the straight line.

6. The comparative test block for composite wing debonding defect detection according to any one of claims 1 to 3, characterized in that: The composite material skin and the adhesive film layer are tightly connected with four polytetrafluoroethylene film discs with different diameters. The diameters of the four polytetrafluoroethylene film discs with different diameters are respectively The foam sandwich block and the adhesive film layer are tightly connected with four polytetrafluoroethylene film discs 2 with different diameters, and the diameters of the four polytetrafluoroethylene film discs 2 with different diameters are respectively 7. The comparative test block for composite wing debonding defect detection according to any one of claims 1 to 3, characterized in that: The comparison test block has a length of 290 to 310 mm and a width of 290 to 310 mm.

8. A method for making a comparative test block for composite wing debonding defect detection according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Use a cutting machine to cut the carbon fiber prepreg and glass fiber prepreg, and put the cut prepregs in order; S2. The laying operation is carried out on the working platform, and the laying dimension lines and laying direction angle lines are marked on the platform; the working table and the mold are wiped clean, and the release cloth is laid on the mold, and the release cloth is closely attached to the mold surface; S3, drying the foam sandwich block material; S4. Lay glass fiber prepreg, multi-layer unidirectional carbon fiber prepreg, and glass fiber prepreg in order of number; during the laying process, pre-compact every 6 layers of prepreg under vacuum conditions; S5. After the prepreg is laid, a layer of medium-temperature curing film is attached to the outermost layer of the prepreg, and a plurality of polytetrafluoroethylene film discs with different diameters are pre-attached to the side where the medium-temperature curing film is bonded to the prepreg; the medium-temperature curing film is pressed lightly by hand to make it close to the prepreg; a plurality of polytetrafluoroethylene film discs with different diameters are also attached to the other side where the medium-temperature curing film is bonded to the prepreg, and then a foam sandwich block material block is attached to the medium-temperature curing film to make a comparison test block preform; S6, placing the mold containing the comparison test block preform into a press, and applying contact pressure until the heating platform contacts the mold; S7. Raise the temperature to 80-85°C at a heating rate of no more than 3°C / min, and keep it warm for 30-35 minutes; pressurize until the mold is closed, and use a feeler gauge to detect the gap, requiring the mold clearance to be no more than 0.1mm; raise the temperature to 120-130°C at a heating rate of no more than 3°C / min, and keep it warm and pressurized for 90-110 minutes; under the pressure-holding condition, reduce the temperature at a rate of no more than 2°C / min or cool naturally to below 60°C to release the pressure, open the mold and take out the comparison test block molded parts; S8, processing the molded parts of the comparison test pieces according to the predetermined size; S9. After processing, remove the moisture from the comparison test block in time; S10. Perform ultrasonic testing on the prepared comparison test blocks and conduct acceptance.

9. The method for making a comparative test block for composite wing debonding defect detection according to claim 8, characterized in that: In step S4, the laying angle of the unidirectional carbon fiber prepreg is 0°, +45° or -45°, and the laying angle of the glass fiber prepreg is ±45°; When laying the prepreg, lay it layer by layer, inspect it layer by layer, and record it layer by layer; the prepreg is kept flat and completely and tightly fitted with the previous layer of prepreg; the pre-compacting time is 15 to 18 minutes, and the vacuum pressure is not greater than -0.094MPa.

10. The method for making a comparative test block for composite wing debonding defect detection according to claim 8, characterized in that: In step S1, the cutting machine is started to cut the prepreg into several pieces with a length and width of 320mm*320mm; in step S7, the mold is opened to take out the comparison test block molded parts with a length and width of 320mm*320mm; in step S8, the comparison test block molded parts are processed according to the size of length and width of 300mm*300mm.

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