Forming preparation method of high-temperature-resistant continuous carbon fiber reinforced polyimide cylinder

Abstract

The invention relates to a forming preparation method of a high-temperature-resistant continuous carbon fiber reinforced polyimide cylinder, which is characterized by comprising the following steps of: 1, disassembling and cleaning a winding core mold and a mold pressing outer mold; secondly, the winding core mold is assembled, and the surface of a cavity used for forming is evenly coated with a release agent together with the mold pressing outer mold; the winding core mold and the mold pressing outer mold are combined to form a closed mold cavity, the winding core mold is used for forming an inner molded surface of a product, and the mold pressing outer mold is used for forming an outer molded surface of the product. Step 3, mounting the polyimide prepreg tape on a winding machine; the method is matched with a mould pressing curing process, has the characteristics of low equipment use cost, low auxiliary material consumption and the like, and can obviously reduce the production cost of the product. According to the forming preparation method, the production efficiency of the product is improved by more than 5 times.

Description

Technical Field

[0001] The invention belongs to the field of composite materials, and in particular relates to a method for forming and preparing a high-temperature resistant continuous carbon fiber reinforced polyimide tube. Background Art

[0002] With the rapid development of airborne radar and battlefield early warning and reconnaissance systems, the perception capabilities of fighters and unmanned aerial vehicles have been greatly extended. The fourth-generation fighters generally have supersonic cruise and high maneuverability. The launch platform and the target move at high speed. The air combat situation changes rapidly. In order to gain the upper hand in the battle, the aircraft must fly farther and farther, fly faster and faster, and launch more flexibly. There is a strong demand for miniaturized and lightweight weapons and equipment. In addition, the shortening of the delivery cycle of weapons and equipment and the reduction of costs have become a trend. High-temperature resistant polyimide materials have the characteristics of high temperature resistance, light weight and high strength, and have gradually begun to be widely used in the aerospace field. High-temperature resistant polyimide tubes are mainly made of carbon fiber reinforced polyimide prepreg as the main raw material. They are formed by high-temperature molding on a hot press after paving, or by high-temperature curing in an autoclave after paving. Manual work accounts for a large proportion in the barrel laying process, and the laying experience of the laying workers also seriously affects the laying quality of the product. The laying of a product often requires 3-5 people to work at the same time for 3-10 days, which is inefficient and difficult to control the quality. In addition, the high-temperature resistant polyimide material is formed by autoclaves, and the temperature resistance of the autoclave is required to be high during the curing process. The current commonly used autoclave temperature is 0-250℃. The purchase cost of autoclaves with higher temperature resistance grades is significantly increased, and the equipment failure rate is also greatly increased. At the same time, auxiliary materials with higher temperature resistance grades are required in the autoclave molding process, which greatly increases the production cost of the product. It is not conducive to the low-cost and high-quality mass production of high-temperature resistant polyimide barrels.

[0003] In view of the current problems of long production cycle, poor production quality consistency and high production cost of high-temperature resistant polyimide tubes, a low-cost, high-quality batch molding method using a winding process to form blanks and a compression molding process to cure products is introduced. The products prepared using the method of the present invention have smooth surfaces and excellent mechanical properties. Since automated winding equipment is used for winding molding, the production efficiency and production quality of the products are improved. In addition, compression molding is used to reduce the cost of using equipment for high-temperature resistant polyimide molding, while reducing the use of auxiliary materials, further reducing the production cost of the products. Summary of the invention

[0004] The purpose of the present invention is to provide a method for forming and preparing a high-temperature resistant continuous carbon fiber reinforced polyimide tube, so as to overcome the defects of the prior art high-temperature resistant polyimide tube, such as long production cycle, poor production quality consistency and high production cost.

[0005] A method for preparing a high temperature resistant continuous carbon fiber reinforced polyimide tube by molding, characterized in that it comprises the following steps:

[0006] Step 1: disassemble and clean the winding core mold and the molded outer mold;

[0007] Step 2: Assemble the winding core mold and evenly apply a release agent on the surface of the cavity used for molding together with the molded outer mold; the winding core mold and the molded outer mold are combined to form a closed mold cavity, the winding core mold is used to mold the inner surface of the product, and the molded outer mold is used to mold the outer surface of the product.

[0008] Step 3: Install the polyimide prepreg tape on the winding machine;

[0009] Step 4: Install the winding core mold on the winding machine, and then use the winding machine to evenly wind the polyimide prepreg tape on the winding core mold under a certain tension and at a certain design angle;

[0010] Step 5, removing the winding core mold for winding the polyimide prepreg tape from the winding machine;

[0011] Step 6, assembling the winding core mold wrapped with the polyimide prepreg tape and the molding outer mold;

[0012] Step 7: Place the assembled mold into a hot press at a set temperature;

[0013] Step 8: Put the assembled mold on the hot press and pressurize it, and set the curing program to cure it;

[0014] Step 9: After the heat preservation and pressure holding of the hot pressing mold on the hot pressing machine is completed, the mold is opened and the product is taken out;

[0015] Step 10: Finally, the product is post-processed such as deburring, and then machined according to the length of the product to obtain 2-3 products. Finally, the product is inspected and packaged;

[0016] Among them, in step 2, the axial length of the winding core mold can be 2-3 times the length of the tube, and 2-3 tubes can be wound at a time.

[0017] In step 4, the polyimide prepreg tape is a roll-shaped prepreg tape of a set width cut from a carbon fiber reinforced polyimide unidirectional prepreg.

[0018] In step S3, the polyimide prepreg tape of a certain width has a width of 6 mm to 10 mm.

[0019] The certain tensioning force in step 4 is 55N-65N, and the certain design angle is [90, ±18, 90].

[0020] In step seven, the assembled mold is placed in a hot press at a certain temperature, and the temperature of the hot press is 80°C-85°C.

[0021] In the curing process described in step eight, the hot pressing temperature is 320° C.-350° C., the heat preservation time of the curing process is 120 min-150 min, and the hot pressing pressure of the curing process is 8 MPa-10 MPa.

[0022] Features and advantages of the present invention:

[0023] The present invention changes the current situation that the traditional manual laying and molding curing of high temperature resistant carbon fiber reinforced polyimide composite materials have low efficiency and high requirements for hardware equipment and auxiliary materials for autoclave curing after winding molding. It utilizes the high efficiency of winding molding and can realize the winding of 2-3 cylinders at a time, while also reducing the proportion of manual work, which has great advantages in improving product production efficiency and quality; in addition, it matches the molding curing process, has the characteristics of low equipment use cost and low auxiliary material consumption, and can significantly reduce the production cost of the product. This molding preparation method improves the production efficiency of the product by more than 5 times. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a flow chart of an embodiment of the present invention;

[0025] Figure 2 These are some basic mechanical properties of the high temperature resistant polyimide tube prepared in the embodiment of the present invention. DETAILED DESCRIPTION

[0026] The invention discloses a high temperature resistant continuous carbon fiber reinforced polyimide tube molding preparation method, which comprises the following steps:

[0027] S1. Disassemble and clean the winding core mold and the molded outer mold;

[0028] S2. Assemble the winding core mold and evenly apply a release agent on the surface of the mold cavity for molding together with the molded outer mold;

[0029] S3. The polyimide prepreg tape is installed on the winding machine;

[0030] S4. The polyimide prepreg tape is evenly wound on the winding mandrel;

[0031] S5. The winding mandrel of the polyimide prepreg tape is removed from the winding machine;

[0032] S6. The winding core mold of the polyimide prepreg tape is assembled with the molded outer mold;

[0033] S7. Place the assembled mold into a hot press at a certain temperature;

[0034] S8. The assembled mold is pressed on the hot press and the curing program is set for curing;

[0035] S9. After the heat preservation and pressure holding on the hot press is completed, the hot pressing mold is opened and the product is taken out;

[0036] S10. Finally, the product is post-processed such as deburring, and then machined according to the length of the product to obtain 2-3 products, and finally the product is inspected and packaged;

[0037] In the step S1, the winding core mold and the molded outer mold are combined to form a closed mold cavity, the winding core mold is used to form the inner surface of the product, and the molded outer mold is used to form the outer surface of the product.

[0038] In the step S1, the axial length of the winding core mold can be 2-3 times the length of the tube, and 2-3 tubes can be wound at one time.

[0039] The specific operation in step S1 is: disassemble the winding core mold and the parts of the molded outer mold, use a non-metallic blade to clean the excess materials attached to the surface, then use a clean white cotton cloth to clean the impurities and other foreign matter on the mold surface, and use the white cotton cloth dipped in alcohol to clean it again until the cavity surface is clean.

[0040] The specific operation in step S2 is: after the winding core mold is assembled, a certain amount of mold release agent is dipped on the cavity surface of the winding core mold and the molded outer mold with cotton cloth, and the mold cavity surface is wiped from one side of the cavity to the other opposite side, and it is repeated 6 times, with an interval of 20 minutes each time.

[0041] In the step S3, the polyimide prepreg tape is a roll-shaped prepreg tape of a certain width cut from a carbon fiber reinforced polyimide unidirectional prepreg, and the prepreg tape is installed on a winding machine.

[0042] The specific operation in step S4 is: the polyimide prepreg tape in step S3 is evenly wound on the winding core mold at a certain design angle under a certain tension.

[0043] The specific operation in step S5 is: after the winding core mold is wound with the polyimide prepreg tape, it is removed from the winding machine.

[0044] The specific operation in step S6 is: assembling the molded outer mold on the outer side of the winding core mold wound with the polyimide prepreg tape.

[0045] The specific operation in step S7 is: placing the assembled mold in step S6 into a hot press at a certain temperature.

[0046] In the step S8, a hot press machine is used to close the hot press mold, and the set curing system is: curing temperature 320° C.-350° C., insulation time 120 min-150 min, and molding pressure 8 MPa-10 MPa.

[0047] Example:

[0048] The present invention can be better understood according to the following examples. However, the contents described in this embodiment are only used to illustrate the present invention, and should not and will not limit the present invention described in the claims.

[0049] A certain type of high temperature resistant polyimide tube molding process. The product uses carbon fiber reinforced polyimide prepreg tape. The molding process is as follows:

[0050] S1. Disassemble and clean the winding core mold and the molded outer mold;

[0051] S2. Assemble the winding core mold and evenly apply a release agent on the surface of the mold cavity for molding together with the molded outer mold;

[0052] S3. The polyimide prepreg tape is installed on the winding machine;

[0053] S4. The polyimide prepreg tape is evenly wound on the winding mandrel;

[0054] S5. The winding mandrel of the polyimide prepreg tape is removed from the winding machine;

[0055] S6. The winding core mold of the polyimide prepreg tape is assembled with the molded outer mold;

[0056] S7. Place the assembled mold into a hot press at a certain temperature;

[0057] S8. The assembled mold is pressed on the hot press and the curing program is set for curing;

[0058] S9. After the heat preservation and pressure holding on the hot press is completed, the hot pressing mold is opened and the product is taken out;

[0059] S10. Finally, the product is post-processed such as deburring, and then machined according to the length of the product to obtain 2-3 products;

[0060] In the step S1, the winding core mold and the molded outer mold are combined to form a closed mold cavity, the winding core mold is used to form the inner surface of the product, and the molded outer mold is used to form the outer surface of the product.

[0061] In the step S1, the axial length of the winding core mold can be 2-3 times the length of the tube, and 2-3 tubes can be wound at one time.

[0062] The specific operation in step S1 is: disassemble the winding core mold and the parts of the molded outer mold, use a non-metallic blade to clean the excess materials attached to the surface, then use a clean white cotton cloth to clean the impurities and other foreign matter on the mold surface, and use a white cotton cloth dipped in a small amount of alcohol to clean again until the cavity surface is clean.

[0063] The specific operation in step S2 is: after the winding core mold is assembled, a proper amount of release agent is applied to the cavity surface of the winding core mold and the molded outer mold with cotton cloth each time, and the mold cavity surface is wiped from one side of the cavity to the other opposite side, and this is repeated 6 times, with an interval of 20 minutes each time.

[0064] In the step S3, the polyimide prepreg tape is a carbon fiber reinforced polyimide unidirectional prepreg cut into a roll-shaped prepreg tape with a width of 8 mm, and 10 rolls of the polyimide prepreg tape are installed on a winding machine.

[0065] The specific operation in step S4 is: the polyimide prepreg tape in step S3 is evenly wound on the winding core mold at a designed angle of [90, ±18, 90] under a tensioning force of 55N-65N.

[0066] The specific operation in step S5 is: after the winding core mold is wound with the polyimide prepreg tape, it is removed from the winding machine.

[0067] The specific operation in step S6 is: assembling the molded outer mold on the outer side of the winding core mold wound with the polyimide prepreg tape.

[0068] The specific operation in step S7 is: placing the assembled mold in step S6 into a hot press at a temperature of 80° C.-85° C.

[0069] In the step S8, a hot press is used to close the hot press mold, and the set curing system is: molding temperature 320° C.-350° C., insulation time 120 min-150 min, and molding pressure 8 MPa-10 MPa.

[0070] A method for preparing a high temperature resistant continuous carbon fiber reinforced polyimide tube by molding, characterized in that it comprises the following steps:

[0071] S1. Disassemble and clean the winding core mold and the molded outer mold;

[0072] S2. Assemble the winding core mold and evenly apply a release agent on the surface of the mold cavity for molding together with the molded outer mold;

[0073] S3. The polyimide prepreg tape is installed on the winding machine;

[0074] S4. The polyimide prepreg tape is evenly wound on the winding mandrel at a certain design angle under a certain tension;

[0075] S5. The winding mandrel of the polyimide prepreg tape is removed from the winding machine;

[0076] S6. The winding core mold of the polyimide prepreg tape is assembled with the molded outer mold;

[0077] S7. Place the assembled mold into a hot press at a certain temperature;

[0078] S8. The assembled mold is pressed on the hot press and the curing program is set for curing;

[0079] S9. After the heat preservation and pressure holding on the hot press is completed, the hot pressing mold is opened and the product is taken out;

[0080] S10. Finally, the product is post-processed such as deburring, and then machined according to the length of the product to obtain 2-3 products, and finally the product is inspected and packaged;

[0081] In step S1, the winding core mold and the molding outer mold are combined to form a closed mold cavity, the winding core mold is used to form the inner surface of the product, and the molding outer mold is used to form the outer surface of the product.

[0082] In step S1, the axial length of the winding core mold can be 2-3 times the length of the tube, and 2-3 tubes can be wound at one time.

[0083] In step S3, the polyimide prepreg tape is a roll-shaped prepreg tape of a certain width cut from a carbon fiber reinforced polyimide unidirectional prepreg.

[0084] In step S3, the polyimide prepreg tape of a certain width has a width of 6 mm to 10 mm.

[0085] The certain tensioning force in step S4 is 55N-65N, and the certain design angle is [90, ±18, 90].

[0086] In step S7, the assembled mold is placed in a hot press at a certain temperature, and the temperature of the hot press is 80°C-85°C.

[0087] In step S8, the curing procedure has a hot pressing temperature of 320° C.-350° C., a heat preservation time of 120 min-150 min, and a hot pressing pressure of 8 MPa-10 MPa.

[0088] The raw material of the high-temperature resistant polyimide tube in the present invention is a carbon fiber reinforced polyimide prepreg tape. The high-temperature resistant polyimide tube molding method involved in the present invention is to use a winding machine to wind the prepreg tape on a winding core mold of a mold to form the prepreg tape, and then install the winding core mold of the wound prepreg tape on the outer mold of a molding mold, and put it on a hot press for curing and molding, thereby solving the problems of low efficiency of artificial paving molding of the high-temperature resistant polyimide tube, poor consistency of molding quality, and high requirements of hot autoclave molding on curing hardware equipment and auxiliary materials, and the high-temperature resistant polyimide tube obtained by the present invention has good mechanical properties.

[0089] The invention discloses a method for forming a high-temperature resistant continuous carbon fiber reinforced polyimide tube, wherein the raw material of the high-temperature resistant polyimide tube is a carbon fiber reinforced polyimide prepreg tape. The method for forming the high-temperature resistant polyimide tube involves using a winding machine to wind the prepreg tape on a winding core mold of a mold, and then installing the winding core mold of the wound prepreg tape on an outer mold of a molding mold, and curing the prepreg tape on a hot press. The method solves the problems of low efficiency of artificial paving and forming of the high-temperature resistant polyimide tube, poor consistency of forming quality, and high requirements of hot autoclave forming on curing hardware equipment and auxiliary materials. The high-temperature resistant polyimide tube obtained by the invention has good mechanical properties.

Claims

1. A method for preparing a high temperature resistant continuous carbon fiber reinforced polyimide tube, characterized in that: The following steps are involved: Step 1: disassemble and clean the winding core mold and the molded outer mold; Step 2: Assemble the winding core mold and evenly apply a release agent on the surface of the cavity used for molding together with the molded outer mold; the winding core mold and the molded outer mold are combined to form a closed mold cavity, the winding core mold is used to mold the inner surface of the product, and the molded outer mold is used to mold the outer surface of the product. Step 3: Install the polyimide prepreg tape on the winding machine; Step 4: Install the winding mandrel on the winding machine, and then use the winding machine to evenly wind the polyimide prepreg tape on the winding mandrel at a certain design angle under a certain tension; Step 5, removing the winding core mold for winding the polyimide prepreg tape from the winding machine; Step 6, assembling the winding core mold wrapped with the polyimide prepreg tape and the molding outer mold; Step 7: Place the assembled mold into a hot press at a set temperature; Step 8: Put the assembled mold on the hot press and pressurize it, and set the curing program to cure it; Step 9: After the heat preservation and pressure holding of the hot pressing mold on the hot pressing machine is completed, the mold is opened and the product is taken out; Step 10. Finally, the product is post-processed by deflashing and other methods, and then machined according to the product length to obtain 2-3 products. Finally, the product is inspected and packaged.

2. A method for preparing a high temperature resistant continuous carbon fiber reinforced polyimide tube as claimed in claim 1, characterized in that: In step 2, the axial length of the winding core mold can be 2-3 times the length of the tube, and 2-3 tubes can be wound at one time.

3. A method for preparing a high temperature resistant continuous carbon fiber reinforced polyimide tube as claimed in claim 1 or 2, characterized in that: In step 4, the polyimide prepreg tape is a roll-shaped prepreg tape of a set width cut from a carbon fiber reinforced polyimide unidirectional prepreg.

4. A method for preparing a high temperature resistant continuous carbon fiber reinforced polyimide tube as claimed in claim 3, characterized in that: In step S3, the polyimide prepreg tape of a certain width has a width of 6 mm to 10 mm.

5. A method for preparing a high temperature resistant continuous carbon fiber reinforced polyimide tube as claimed in claim 1 or 2, characterized in that: The certain tensioning force in step 4 is 55N-65N, and the certain design angle is [90, ±18, 90].

6. A method for forming a high temperature resistant continuous carbon fiber reinforced polyimide tube as claimed in claim 1 or 2, characterized in that: In step seven, the assembled mold is placed in a hot press at a certain temperature, and the temperature of the hot press is 80°C-85°C.

7. A method for preparing a high temperature resistant continuous carbon fiber reinforced polyimide tube as claimed in claim 1 or 2, characterized in that: In the curing process described in step eight, the hot pressing temperature is 320° C.-350° C., the heat preservation time of the curing process is 120 min-150 min, and the hot pressing pressure of the curing process is 8 MPa-10 MPa.

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