Three-dimensional fabric prepreg sewing manufacturability evaluation device and method

Abstract

The invention discloses a device and a method for evaluating sewing manufacturability of three-dimensional fabric prepreg. The device comprises a fixing mechanism and a needle puncture driving force testing mechanism, the three-dimensional fabric prepreg is fixed through the fixing mechanism and then placed on the platform, the needle puncture pushing force testing mechanism pushes a needle to move and penetrate through the three-dimensional fabric prepreg in a manner of being perpendicular to the three-dimensional fabric prepreg through air pressure, the pressure is tested through a high-precision pressure gauge, and then the pushing force of the needle is calculated. Finally, the sewing manufacturability of the three-dimensional fabric prepreg is represented through the pushing force. The method is simple in operation process, high in test precision and capable of quantitatively evaluating the sewing manufacturability of the three-dimensional fabric prepreg with the thickness of 1-30 mm.

Description

Technical Field

[0001] The invention belongs to the technical field of fabric prepreg process performance evaluation, and in particular relates to a three-dimensional fabric prepreg sewing process performance evaluation device and method. Background Art

[0002] Currently, 70% of advanced composite products are made of prepregs that are stacked and cured. Prepreg refers to a semi-finished product that is stored and prepared after fibers or fabrics are impregnated with a resin matrix under strictly controlled conditions and then processed through a certain process. It is an important intermediate material for manufacturing composite products. As early as the late 1940s, foreign countries began to use glass fiber reinforced prepregs. It was not until the late 1960s and early 1970s that with the advent of high-performance fibers such as carbon fiber and aramid, the process stability and quality control of prepregs were reliably guaranteed, and the preparation technology of various prepregs has made great progress. Afterwards, with the continuous improvement of the performance of reinforcing fibers and resin matrices, the research and development of prepregs has been promoted, and its process technology has become increasingly mature and its application scope has continued to expand.

[0003] The fibers in prepregs are in several forms, such as chopped fibers, fiber mats, fiber cloths, and three-dimensional fiber fabrics. In terms of performance, due to the interaction between fibers, the composite materials prepared by three-dimensional fabric prepregs have excellent overall mechanical properties; in terms of production effect, compared with the ply, the three-dimensional fabric prepreg itself has a large thickness, which can quickly prepare composite materials and achieve efficiency improvement. Three-dimensional fabric prepregs have become an emerging and important prepreg.

[0004] At present, the main aspects of evaluating the performance of prepregs include volatile content, resin content, gel time, viscosity, resin fluidity, surface density, fiber surface density, etc. These evaluations are mainly for short fiber and fiber cloth fabric prepregs. In the process of preparing composite materials with three-dimensional fabric prepregs, they often need to be overlapped and sewn together. Good sewing processability is the basis for the wide application of three-dimensional fabric prepregs. At present, there is no evaluation standard and method for the sewing processability of three-dimensional fabric prepregs. Summary of the invention

[0005] The technical problem solved by the present invention is to overcome the deficiencies of the prior art and provide a device and method for evaluating the sewing processability of a three-dimensional fabric prepreg, aiming to achieve quantitative evaluation of the sewing processability of the three-dimensional fabric prepreg.

[0006] In order to solve the above technical problems, the present invention discloses a three-dimensional fabric prepreg sewing processability evaluation device, comprising: a fixing mechanism and a needle puncture driving force testing mechanism;

[0007] The fixing mechanism comprises: a first clamping plate, a second clamping plate, a third clamping plate and a fourth clamping plate; wherein the first clamping plate and the second clamping plate form a group, the third clamping plate and the fourth clamping plate form a group, and each group of clamping plates is connected by two screws;

[0008] The needle puncture pushing force testing mechanism comprises: a piston, a cylinder body, a needle, a pipeline A, a pipeline B, a pipeline C, a pipeline D, a valve A, a pressure gauge A, a valve B, a pressure gauge B, a valve C and a valve D; wherein, the piston is located in the cylinder body and can make up and down reciprocating movements in the cylinder body; the needle is arranged at the bottom of the piston; the pipeline A and the pipeline C are respectively connected to the upper part of the cylinder body; the pipeline B and the pipeline D are respectively connected to the lower part of the cylinder body; the valve A and the pressure gauge A are arranged in sequence on the pipeline A along the air intake direction; the valve B and the pressure gauge B are arranged in sequence on the pipeline B along the air intake direction; the valve C is arranged on the pipeline C; the valve D is arranged on the pipeline D.

[0009] In the above-mentioned three-dimensional fabric prepreg sewing processability evaluation device, the fixing mechanism is used to fix the three-dimensional fabric prepreg.

[0010] In the above-mentioned three-dimensional fabric prepreg sewing processability evaluation device, the needle penetration driving force testing mechanism is used to implement the sewing processability test of the fixed three-dimensional fabric prepreg.

[0011] In the above-mentioned three-dimensional fabric prepreg sewing processability evaluation device, the structural size parameters of the first splint, the second splint, the third splint and the fourth splint are consistent; wherein the width of the splint is 5 to 10 cm, the length is 5 to 20 cm, and the thickness is 1 to 3 cm.

[0012] In the above-mentioned three-dimensional fabric prepreg sewing processability evaluation device, one end of pipeline A is connected to the cylinder body, and the other end is connected to air source A; one end of pipeline B is connected to the cylinder body, and the other end is connected to air source B.

[0013] In the above-mentioned three-dimensional fabric prepreg sewing processability evaluation device, the accuracy of pressure gauge A and pressure gauge B are both ≤10Pa, and the measuring range is both ≥5MPa.

[0014] In the above-mentioned three-dimensional fabric prepreg sewing processability evaluation device, the length of the needle minus the thickness of the fabric prepreg is greater than 1 to 2 cm; and the diameter of the needle is 1 to 3 mm.

[0015] Correspondingly, the present invention also discloses a method for evaluating the sewing processability of a three-dimensional fabric prepreg based on the above device, comprising:

[0016] Placing one side of the three-dimensional fabric prepreg between the first clamping plate and the second clamping plate and clamping them by tightening the screws; placing the other side of the three-dimensional fabric prepreg between the third clamping plate and the fourth clamping plate and clamping them by tightening the screws;

[0017] The three-dimensional fabric prepreg and the fixing mechanism are placed as a whole just below the needle of the needle penetration pushing force testing mechanism;

[0018] Close valve B and valve C, and open valve D; then, open valve A, and when the needle starts to move, record the pressure P1 of pressure gauge A at this time; when the needle moves to pass through the three-dimensional fabric prepreg, record the pressure P2 of pressure gauge A at this time;

[0019] Close valve A and valve D, and open valve C; then, open valve B, and when the piston rises to the starting position, close valve B;

[0020] Based on the recorded pressure P1 and pressure P1, the thrust F when the needle passes through the three-dimensional fabric prepreg is calculated;

[0021] According to the calculated thrust F, the evaluation result of the stitching processability of the three-dimensional fabric prepreg is given; among them, when F≤5N, the stitching processability evaluation result is excellent; when 5N<F≤10N, the stitching processability evaluation result is good; when 10N<F, the stitching processability evaluation result is poor.

[0022] In the above method, F=S*(P2-P1); wherein S represents the area of ​​the circular region on the upper surface of the piston.

[0023] In the above method, the movement speed of the needle is ensured to be 0.5 to 2.0 mm / s by controlling the opening of valve A or valve B.

[0024] The present invention has the following advantages:

[0025] The invention discloses a device and method for evaluating the sewing processability of a three-dimensional fabric prepreg, which are simple to operate and have good effects, and can quickly and quantitatively evaluate the sewing processability of the three-dimensional fabric prepreg. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of a three-dimensional fabric prepreg sewing processability evaluation device in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0028] Reference Figure 1 In this embodiment, the three-dimensional fabric prepreg sewing processability evaluation device includes: a fixing mechanism and a needle penetration driving force testing mechanism. The fixing mechanism is used to fix the three-dimensional fabric prepreg; the needle penetration driving force testing mechanism is used to test the sewing processability of the fixed three-dimensional fabric prepreg.

[0029] The fixing mechanism mainly includes: a first clamping plate 101, a second clamping plate 102, a third clamping plate 103 and a fourth clamping plate 104. The first clamping plate 101 and the second clamping plate 102 are a group, and the third clamping plate 103 and the fourth clamping plate 104 are a group, and each group of clamping plates is connected by two screws. The first clamping plate 101, the second clamping plate 102, the third clamping plate 103 and the fourth clamping plate 104 have the same structural size parameters; the width of the clamping plate is 5 to 10 cm, the length is 5 to 20 cm, and the thickness is 1 to 3 cm.

[0030] The needle puncture driving force testing mechanism mainly includes: a piston 201, a cylinder body 202, a needle 203, a pipeline A204, a pipeline B205, a pipeline C206, a pipeline D207, a valve A208, a pressure gauge A209, a valve B210, a pressure gauge B211, a valve C212 and a valve D213. Among them, the piston 201 is located in the cylinder body 202 and can move up and down in the cylinder body 202; the needle 203 is set at the bottom of the piston 201; the pipeline A204 and the pipeline C206 are respectively connected to the upper part of the cylinder body 202; the pipeline B205 and the pipeline D207 are respectively connected to the lower part of the cylinder body 202; the pipeline A204 is provided with a valve A208 and a pressure gauge A209 in sequence along the air intake direction; the pipeline B205 is provided with a valve B210 and a pressure gauge B211 in sequence along the air intake direction; the pipeline C206 is provided with a valve C212; the pipeline D207 is provided with a valve D213. One end of the pipeline A204 is connected to the cylinder body 202, and the other end is connected to the gas source A; one end of the pipeline B205 is connected to the cylinder body 202, and the other end is connected to the gas source B. The precision of pressure gauge A209 and pressure gauge B211 are both ≤10Pa, and the measuring range is both ≥5MPa. The length of needle 203-the thickness of fabric prepreg>1-2cm; the diameter of needle 203 is 1-3mm.

[0031] In this embodiment, the method for evaluating the sewing processability of a three-dimensional fabric prepreg based on the above-mentioned device includes:

[0032] S1, place one side of the three-dimensional fabric prepreg 300 between the first clamping plate 101 and the second clamping plate 102, and clamp it by tightening the screws; place the other side of the three-dimensional fabric prepreg 300 between the third clamping plate 103 and the fourth clamping plate 104, and clamp it by tightening the screws.

[0033] S2, placing the three-dimensional fabric prepreg 300 and the fixing mechanism as a whole just below the needle 203 of the needle penetration pushing force testing mechanism.

[0034] S3, close valve B210 and valve C212, open valve D213; then, open valve A208, when needle 203 starts to move, record the pressure P1 at this time on pressure gauge A209; when needle 203 moves to pass through the three-dimensional fabric prepreg 300, record the pressure P2 at this time on pressure gauge A209.

[0035] S4, close valve A208 and valve D213, open valve C212; then, open valve B210, and when piston 201 rises to the starting position, close valve B210.

[0036] S5, according to the recorded pressure P1 and pressure P1, the thrust F when the needle 203 passes through the three-dimensional fabric prepreg 300 is calculated. Wherein, F=S*(P2-P1), S represents the area of ​​the circular region on the upper surface of the piston 201.

[0037] S6, according to the calculated thrust F, the evaluation result of the sewing processability of the three-dimensional fabric prepreg 300 is given. When F≤5N, the evaluation result of the sewing processability is excellent; when 5N<F≤10N, the evaluation result of the sewing processability is good; when 10N<F, the evaluation result of the sewing processability is poor.

[0038] It should be noted that when controlling valve A208 and valve B210, they need to be opened slowly. By controlling the opening of valve A208 or valve B210, the movement speed of needle 203 is ensured to be 0.5-2.0 mm / s, thereby achieving slow movement of needle 203.

[0039] Based on the above embodiments, two specific examples are provided below for illustration.

[0040] Example 1

[0041] The three-dimensional fabric prepreg sewing processability evaluation device is made of 45# steel, the size of the splint is 10*5*2cm; the piston diameter is 10cm, and the upper surface area of ​​the piston is 78.5cm 2 The diameter of the needle is 1 mm and the length is 3 cm. The pressure gauge is a digital pressure gauge with an accuracy of 1 Pa and a range of 10 MPa.

[0042] Test the sewing processability of 10mm thick three-dimensional fabric prepreg, the steps are as follows:

[0043] One side of the three-dimensional fabric prepreg is placed between the first clamping plate and the second clamping plate, and is clamped by tightening screws; the other side of the three-dimensional fabric prepreg is placed between the third clamping plate and the fourth clamping plate, and is clamped by tightening screws.

[0044] The three-dimensional fabric prepreg and the fixing mechanism are placed as a whole just below the needle of the needle penetration pushing force testing mechanism.

[0045] Close valve B and valve C, and open valve D; then, slowly open valve A. When the needle starts to move at a speed of 1 mm / s, record the pressure P1 = 10200 Pa on pressure gauge A at this time; when the needle touches the three-dimensional fabric prepreg, the needle stops moving, and continue to slowly increase valve A. When the needle continues to move at a speed of 1 mm / s and passes through the three-dimensional fabric prepreg by 1 cm, record the pressure P2 = 10800 Pa on pressure gauge A at this time.

[0046] Close valve A and valve D, and open valve C; then, open valve B, and when the piston rises to the starting position, close valve B.

[0047] The thrust force F when the needle passes through the three-dimensional fabric prepreg is calculated to be 600*78.5*10 -4 =4.7N, the suture processability evaluation result is excellent.

[0048] Example 2

[0049] The three-dimensional fabric prepreg sewing processability evaluation device is made of 45# steel, the size of the splint is 10*5*2cm; the piston diameter is 10cm, and the upper surface area of ​​the piston is 78.5cm 2 The diameter of the needle is 1 mm and the length is 3 cm. The pressure gauge is a digital pressure gauge with an accuracy of 1 Pa and a range of 10 MPa.

[0050] Test the sewing processability of 15mm thick three-dimensional fabric prepreg, the steps are as follows:

[0051] One side of the three-dimensional fabric prepreg is placed between the first clamping plate and the second clamping plate, and is clamped by tightening screws; the other side of the three-dimensional fabric prepreg is placed between the third clamping plate and the fourth clamping plate, and is clamped by tightening screws.

[0052] The three-dimensional fabric prepreg and the fixing mechanism are placed as a whole just below the needle of the needle penetration pushing force testing mechanism.

[0053] Close valve B and valve C, and open valve D; then, slowly open valve A. When the needle starts to move at a speed of 0.5 mm / s, record the pressure P1 = 10100 Pa on pressure gauge A; when the needle touches the three-dimensional fabric prepreg, the needle stops moving, and continue to slowly increase valve A. When the needle continues to move at a speed of 0.5 mm / s and passes through the three-dimensional fabric prepreg by 1.5 cm, record the pressure P2 = 11200 Pa on pressure gauge A.

[0054] Close valve A and valve D, and open valve C; then, open valve B, and when the piston rises to the starting position, close valve B.

[0055] The thrust force F when the needle passes through the three-dimensional fabric prepreg is calculated to be 1100*78.5*10 -4 =8.6N, the suture processability evaluation result is good.

[0056] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

[0057] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A three-dimensional fabric prepreg sewing processability evaluation device, characterized in that: include: Fixing mechanism and needle penetration pushing force testing mechanism; The fixing mechanism comprises: a first clamping plate (101), a second clamping plate (102), a third clamping plate (103) and a fourth clamping plate (104); wherein the first clamping plate (101) and the second clamping plate (102) form a group, and the third clamping plate (103) and the fourth clamping plate (104) form a group, and each group of clamping plates is connected by two screws; The needle puncture driving force testing mechanism comprises: a piston (201), a cylinder body (202), a needle (203), a pipeline A (204), a pipeline B (205), a pipeline C (206), a pipeline D (207), a valve A (208), a pressure gauge A (209), a valve B (210), a pressure gauge B (211), a valve C (212) and a valve D (213); wherein the piston (201) is located in the cylinder body (202) and can move up and down in the cylinder body (202); the needle (203) is arranged in the piston (201 ) bottom; pipeline A (204) and pipeline C (206) are respectively connected to the upper part of the cylinder body (202); pipeline B (205) and pipeline D (207) are respectively connected to the lower part of the cylinder body (202); valve A (208) and pressure gauge A (209) are sequentially arranged on pipeline A (204) along the air intake direction; valve B (210) and pressure gauge B (211) are sequentially arranged on pipeline B (205) along the air intake direction; valve C (212) is arranged on pipeline C (206); and valve D (213) is arranged on pipeline D (207).

2. The three-dimensional fabric prepreg sewing processability evaluation device according to claim 1 is characterized in that: The fixing mechanism is used to fix the three-dimensional fabric prepreg.

3. The three-dimensional fabric prepreg sewing processability evaluation device according to claim 2, characterized in that: The needle penetration force testing mechanism is used to carry out a stitching processability test on the fixed three-dimensional fabric prepreg.

4. The three-dimensional fabric prepreg sewing processability evaluation device according to claim 1, characterized in that: The first clamping plate (101), the second clamping plate (102), the third clamping plate (103) and the fourth clamping plate (104) have the same structural dimension parameters; wherein the width of the clamping plate is 5 to 10 cm, the length is 5 to 20 cm, and the thickness is 1 to 3 cm.

5. The three-dimensional fabric prepreg sewing processability evaluation device according to claim 1, characterized in that: One end of the pipeline A (204) is connected to the cylinder body (202), and the other end is connected to the gas source A; one end of the pipeline B (205) is connected to the cylinder body (202), and the other end is connected to the gas source B.

6. The three-dimensional fabric prepreg sewing processability evaluation device according to claim 1, characterized in that: The accuracy of pressure gauge A (209) and pressure gauge B (211) are both ≤10Pa, and the range is both ≥5MPa.

7. The three-dimensional fabric prepreg sewing processability evaluation device according to claim 1, characterized in that: The length of the needle (203) is greater than the thickness of the fabric prepreg by 1 to 2 cm; the diameter of the needle (203) is 1 to 3 mm.

8. A method for evaluating the sewing processability of three-dimensional fabric prepregs based on the device of claim 1, characterized in that: include: Placing one side of the three-dimensional fabric prepreg (300) between the first clamping plate (101) and the second clamping plate (102) and clamping them by tightening screws; placing the other side of the three-dimensional fabric prepreg (300) between the third clamping plate (103) and the fourth clamping plate (104) and clamping them by tightening screws; Placing the three-dimensional fabric prepreg (300) and the fixing mechanism as a whole directly below the needle (203) of the needle penetration driving force testing mechanism; Close valve B (210) and valve C (212), and open valve D (213); then, open valve A (208), and when the needle (203) starts to move, record the pressure P1 of pressure gauge A (209) at this time; when the needle (203) moves to pass through the three-dimensional fabric prepreg (300), record the pressure P2 of pressure gauge A (209) at this time; Close valve A (208) and valve D (213), and open valve C (212); then, open valve B (210), and when the piston (201) rises to the starting position, close valve B (210); Based on the recorded pressure P1 and pressure P1, the thrust F when the needle (203) passes through the three-dimensional fabric prepreg (300) is calculated; According to the thrust force F obtained by calculation, the evaluation result of the sewing processability of the three-dimensional fabric prepreg (300) is given; wherein, when F≤5N, the evaluation result of the sewing processability is excellent; when 5N<F≤10N, the evaluation result of the sewing processability is good; and when 10N<F, the evaluation result of the sewing processability is poor.

9. The method according to claim 8, characterized in that F=S*(P2-P1); wherein S represents the area of ​​the circular region on the upper surface of the piston (201).

10. The method according to claim 9, characterized in that By controlling the opening of valve A (208) or valve B (210), the movement speed of the needle (203) is ensured to be 0.5 to 2.0 mm / s.

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