Thermoplastic composite material induction repair method based on carbon nano tube (CNTs) reinforcement

Abstract

The invention provides a thermoplastic composite material induction repair method based on carbon nano tube (CNTs) reinforcement, and relates to the field of composite material repair. According to the method, high conductivity and thermal stability of CNTs are utilized, an electromagnetic induction heating technology is adopted, a repairing material is rapidly melted, and therefore rapid and accurate repairing of damage of the thermoplastic composite material is achieved. The repairing process comprises the steps of damage detection, local injection of the CNTs reinforcing agent, induction heating, curing forming and the like. According to the method, the repairing efficiency is effectively improved, material waste is reduced, and the mechanical property of the repaired part is enhanced. The method is suitable for repairing structural damage of thermoplastic composite materials in the fields of aerospace, automobile manufacturing, sports equipment and the like.

Description

Technical Field

[0001] The invention relates to the technical field of composite material repair, and in particular to an induction repair method for thermoplastic composite materials reinforced by carbon nanotubes (CNTs). Background Art

[0002] With the rapid development of modern industry, thermoplastic composites are increasingly used in aerospace, automobile manufacturing, sports equipment and other fields. However, damage will inevitably occur during use. If these damages are not repaired in time, they will seriously affect the integrity and service life of the structure. Traditional composite material repair methods have many limitations. First, the repair process is often time-consuming and inefficient, and cannot meet the needs of rapid repair. Secondly, traditional methods waste materials seriously during the repair process, and the mechanical properties after repair are often difficult to reach the original state, causing the repaired part to become a new weak link. In addition, the repair process has a low degree of automation and relies on manual operation, which not only increases the labor intensity, but also limits the repair accuracy and consistency. Therefore, the development of an efficient and precise composite material repair technology is of great significance to ensure industrial safety and extend product life.

[0003] To solve the above problems, the present invention provides an induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs). The method uses an industrial control system, a nozzle heating system, a spraying system, and a monitoring system to collaboratively complete the repair work of the composite material. The method can form a repair scheme according to the damage morphology, and autonomously feed the wire to complete the precise repair operation, thereby improving the repair efficiency and accuracy. In addition, the design of the double nozzles further ensures the feasibility of the repair method, and can adjust the ratio of carbon nanotube reinforcing agent to matrix according to different repair schemes, thereby adjusting the repair material with the best performance. Through the present invention, frequent manual intervention can be avoided, which not only improves the repair efficiency, but also avoids the delay of repair time caused by human factors. The automated operation can accurately control the spraying and heating position of the material, reduce the accumulation of the material in the non-defective area, and further reduce the waste of materials. Through precise temperature control and repair schemes, the internal structure of the repaired material is more uniform, and the material performance of the defective area is more fully restored, ensuring that the repaired material has good mechanical properties in all directions and positions. The present invention has brought important technical breakthroughs in the field of composite material repair technology. Summary of the invention

[0004] The present invention aims at solving the problems of low efficiency, uneven repair and insufficient precision in the process of composite material damage repair, and provides an induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs).

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for induction repair of thermoplastic composite materials reinforced with carbon nanotubes (CNTs), characterized by comprising an industrial control system, a nozzle heating system, a spraying system, and a monitoring system, wherein:

[0007] The industrial control system comprises a disperser (1), a mixer (2), an industrial control center (3), an induction heating control system (5), a robot support, a six-axis robot machine (8), and a repair operation platform (11);

[0008] The nozzle heating system comprises an induction heating power supply (4), an induction heating control system (5), and a protection device (9);

[0009] The spraying system comprises a carbon nanotube extrusion nozzle (12) and a composite material extrusion nozzle (13);

[0010] The monitoring system comprises a three-dimensional scanning camera (14) and an infrared thermometer (7);

[0011] The induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs) is characterized in that the nozzle heating temperature is controlled by an induction heating control system, and the electromagnetic induction heating principle is used to achieve rapid and accurate repair of damaged parts of the thermoplastic composite materials. A telescopic device is installed between the carbon nanotube extrusion nozzle (12) and the composite material extrusion nozzle (13), and the robot is also connected to the telescopic device, so as to achieve flexible control of the repair area and improve the automation and accuracy of the repair process.

[0012] The induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs) is characterized in that a carbon nanotube extrusion nozzle (12), a composite material extrusion nozzle (13) and a protective device (9) are fixed on a robotic arm, a wire feed line is connected to a mixer via the robotic arm, an induction heating power line is connected to an induction heating device and fixed to the robotic arm, an automatic extrusion device is provided at the connection between the wire feed line and the mixer, and a pressure sensor is installed to avoid damage to the wire feed pipeline. Considering the internal wear of the wire feed pipeline, the wire feed device can be replaced regularly to ensure the smooth progress of the wire feeding process.

[0013] The induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs) is characterized in that a carbon nanotube extrusion nozzle (12) and a composite material extrusion nozzle (13) cooperate with each other, the carbon nanotube extrusion nozzle (12) can independently spray out molten carbon nanotube material, and the composite material extrusion nozzle (13) can spray out molten thermoplastic composite materials with carbon nanotubes as the reinforcement phase. This dual nozzle design helps to accurately control the distribution of materials and the repair quality.

[0014] The induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs) is characterized in that a three-dimensional scanning camera (14) performs digital model analysis on material defects to obtain a repair plan, and an infrared thermometer (7) monitors the temperature in real time and feeds back the temperature data to the industrial control center (3). For the protection device of the induction heating system, sensor fans controlled by the heating protection device (9) are installed on both sides of the dual nozzle design to cool the induction heating device and prevent the dual nozzles from being damaged due to local high temperature, which affects the repair effect.

[0015] The induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs) is characterized in that a three-dimensional scanning camera (14) performs digital model analysis on material defects to obtain a repair plan, and an infrared thermometer (7) monitors the temperature in real time and feeds back the temperature data to the industrial control center (3). For the protection device of the induction heating system, sensor fans controlled by the heating protection device (9) are installed on both sides of the dual nozzle design to cool the induction heating device and prevent the dual nozzles from being damaged due to local high temperature, which affects the repair effect.

[0016] The induction repair method of thermoplastic composite material reinforced with carbon nanotubes (CNTs) is characterized by comprising the following steps:

[0017] Step 1: Add fully dispersed carbon nanotubes and a thermoplastic composite material containing carbon nanotubes as a reinforcement phase into the feed port of a mixer.

[0018] Step 2: Turn on the power of the industrial control center (3). At this time, the three-dimensional scanning camera (14) starts to work, scans the surface to be repaired, obtains its detailed shape and feature information, and transmits these data back to the industrial control center (3). The industrial control center (3) analyzes the model data of the area to be repaired, and thus formulates a detailed repair plan, and sends the plan to various relevant parts of the entire repair system.

[0019] Step three, according to the obtained repair plan, determine the key process parameters such as appropriate temperature parameters, spinning speed and induction heating frequency through the induction heating control system (5) and the infrared temperature measuring instrument (7).

[0020] Step 4: Start the nozzle heating system, spraying system and monitoring system. According to the previously formulated repair plan, control the six-axis robot (8) to perform precise repair operations along the predetermined repair path until the repair work of all the areas to be repaired on the workpiece is completed.

[0021] The beneficial effects of the present invention are:

[0022] The present invention is an induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs). The high conductivity and thermal stability of CNTs are utilized to realize rapid and accurate repair of damaged parts of materials through the principle of electromagnetic induction heating. The repair process covers steps such as damage detection, local injection of CNTs reinforcing agent, induction heating and curing molding, which effectively improves the repair efficiency, reduces material waste and enhances the mechanical properties of the repaired parts. The nozzle heating temperature is accurately controlled by the induction heating control system, and the robot is connected with the telescopic device to realize flexible control of the repair area, thereby improving the automation and accuracy of the repair process. The dual nozzle design helps to accurately control the material distribution and ensure the quality of the repair. At the same time, a three-dimensional scanning camera is used to perform digital model analysis on material defects to obtain a repair plan, and an infrared thermometer monitors the temperature in real time and feeds back the data to the industrial control center to ensure the accuracy and safety of the repair process. In addition, sensor fans controlled by a heating protection device are equipped on both sides of the dual nozzles to cool the induction heating device to prevent the nozzle from being damaged by local high temperature and affecting the repair effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of an induction repair method for a thermoplastic composite material with carbon nanotubes as a reinforcement phase provided by an embodiment of the present invention;

[0024] Figure 2 It is a schematic diagram of a thermoplastic composite material induction repair and protection device with carbon nanotubes as a reinforcement phase provided by an embodiment of the present invention;

[0025] Figure 3 It is a schematic diagram of an extrusion nozzle for induction repair of a thermoplastic composite material with carbon nanotubes as a reinforcement phase provided by an embodiment of the present invention;

[0026] Figure 4 It is a schematic diagram of a carbon nanotube extrusion nozzle for induction repair of a thermoplastic composite material with carbon nanotubes as a reinforcement phase provided by an embodiment of the present invention;

[0027] Explanation of numbers in the figure: 1. Disperser; 2. Mixer; 3. Industrial control center; 4. Induction heating power supply; 5. Induction heating control system; 6. Robot support; 7. Infrared thermometer; 8. Six-axis robot; 9. Protection device; 10. Working platform; 11. Repair work platform; 12. Carbon nanotube extrusion nozzle; 13. Composite material extrusion nozzle; 14. 3D scanning camera; 15. Nozzle induction heating controller; 16. Composite material delivery pipeline; 17. Sensor cooling fan; 18. Carbon nanotube delivery pipeline. DETAILED DESCRIPTION

[0028] Step 1: Pour the dispersed carbon nanotubes and thermoplastic composite material into the feeding port of the mixer.

[0029] Step 2: Turn on the power of the industrial control center (3), obtain the morphological features of the interface to be repaired through the three-dimensional scanning camera (14), and feed it back to the industrial control center (3), obtain the repair plan by analyzing the model data of the area to be repaired, and transmit the repair plan to the entire repair system.

[0030] Step three, according to the obtained repair plan, use the induction heating control system (5) and the infrared temperature measuring instrument (7) to set the appropriate temperature, spinning speed and induction heating frequency.

[0031] Step 4, turn on the nozzle heating system, spraying system and monitoring system, and according to the established repair plan, control the six-axis robot machine (8) to complete the repair work on the established repair path until the area to be repaired of the workpiece is completely repaired. Specific embodiments

[0033] The present invention relates to an induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs), and the present invention is further described in detail below through drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0034] Figure 1 It is a specific embodiment of the present invention. The figure shows an induction repair device based on carbon nanotube (CNTs) reinforced thermoplastic composite material. The damaged workpiece is a glass fiber reinforced plastic (GFRP) aircraft skin, and the selected repair material is a carbon nanotube reinforced nylon 66 thermoplastic composite material;

[0035] In the embodiment, the dispersed carbon nanotubes and the carbon nanotube-reinforced nylon 66 thermoplastic composite material with carbon nanotubes as the reinforcement phase are poured into the feed port of the mixer to ensure that the materials are fully mixed to facilitate the subsequent spraying process;

[0036] In the embodiment, the power of the industrial control center is turned on, and the 3D scanning camera is started to obtain the morphological features of the interface to be repaired, and the features are fed back to the industrial control center. By analyzing the model data of the area to be repaired, the industrial control center formulates a repair plan and transmits the repair plan to the entire repair system;

[0037] According to the repair plan, the induction heating control system and infrared thermometer were used to set the appropriate temperature, spinning speed, and induction heating frequency. The temperature was set to 230°C, the spinning speed was 5mm / s, and the induction heating frequency was 30MHz.

[0038] Turn on the nozzle heating system, spray carbon nanotube extrusion nozzle and composite material extrusion nozzle to cooperate with each other, accurately spray molten carbon nanotube material and molten thermoplastic composite material system and monitoring system with carbon nanotubes as reinforcement phase, control the six-axis robot machine to complete the repair work on the established repair path, and use the infrared thermometer to monitor the temperature of the repair area in real time to ensure that the induction heating control system can adjust the heating power in time to maintain a constant repair temperature. The sensor fan controlled by the heating protection device cools down the induction heating device to prevent equipment damage due to local high temperature.

[0039] After the repair is completed, the repair area is scanned again using a 3D scanning camera and compared with the original model data to ensure that the repair quality meets the requirements.

[0040] In the embodiment, if the repair quality meets the requirements, subsequent curing and post-processing work is performed to ensure the mechanical properties and durability of the repaired part.

[0041] The above description is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be regarded as within the protection scope of the present invention.

Claims

1. An induction repair method for thermoplastic composite materials reinforced with carbon nanotubes (CNTs), which features include an industrial control system, a nozzle heating system, a spraying system, and a monitoring system. The industrial control system comprises a disperser (1), a mixer (2), an industrial control center (3), an induction heating control system (5), a robot support (6), a six-axis robot machine (8), and a repair operation platform (11); The nozzle heating system comprises an induction heating power supply (4), an induction heating control system (5), and a protection device (9); The spraying system comprises a carbon nanotube extrusion nozzle (12) and a composite material extrusion nozzle (13); The monitoring system comprises a three-dimensional scanning camera (14) and an infrared thermometer (7); The composite material is a hydrogen-bonded composite material, in which the hydroxylated carbon nanotubes added as a reinforcing agent to the epoxy resin matrix can cooperate with the matrix resin material to show good repair performance in the range of room temperature to 80°C. In addition, the composite material may also contain materials such as oligomeric acid, diethylenetriamine and urea, which work synergistically with carbon nanotubes to form a self-repairing polymer with strong and weak hydrogen bonds, in which the strong cross-linked hydrogen bonds make the self-repairing polymer strong and elastic, and the weak cross-linked hydrogen bonds consume strain energy through reversible fracture and deformation, reducing the sensitivity of the material to minor damage, thereby improving the damage repair effect.

2. The induction repair method of thermoplastic composite material based on carbon nanotubes (CNTs) reinforcement according to claim 1 is characterized in that: Electromagnetic induction heating technology is used to quickly melt the repair material, thereby realizing rapid and accurate repair of thermoplastic composite material damage. A telescopic device is installed between the carbon nanotube extrusion nozzle (12) and the composite material extrusion nozzle (13), and the robot is also connected with the telescopic device, so as to realize flexible control of the repair area, and can quickly and accurately perform heating, extrusion, and coating, thereby improving the automation and accuracy of the repair process.

3. The induction repair method of thermoplastic composite material reinforced with carbon nanotubes (CNTs) according to claim 1, characterized in that: The carbon nanotube extrusion nozzle (12), the composite material extrusion nozzle (13) and the protection device (9) are fixed on the mechanical arm. The wire feed line is connected to the mixer through the mechanical arm. The connection point is equipped with an automatic extrusion device and a pressure sensor to avoid the problem of wire feed pipeline damage. The carbon nanotube extrusion nozzle (12) and the composite material extrusion nozzle (13) cooperate with each other. The carbon nanotube extrusion nozzle (12) can independently spray out molten carbon nanotube material, and the composite material extrusion nozzle (13) can spray out molten thermoplastic composite material with carbon nanotubes as reinforcement phase. This double nozzle design helps to accurately control the distribution of materials and the repair quality. Sensor fans controlled by the heating protection device (9) are installed on both sides of the double nozzles to cool the induction heating device to prevent the double nozzles from being damaged due to local high temperature and affecting the repair effect.

4. The induction repair method of thermoplastic composite material based on carbon nanotubes (CNTs) reinforcement according to claim 1, characterized in that: A three-dimensional scanning camera (14) is used to perform digital model analysis on the material defects to obtain a repair plan, and an infrared thermometer (7) is used to monitor in real time and feed back the temperature data to the industrial control center (3). With the help of the infrared thermometer and the feedback control of the industrial control center, the temperature of different parts can be adjusted separately to ensure that the repair effect of the entire component is uniform and reliable. This method can accurately measure the length, width and depth of the defect, and can maximize the repair effect and avoid over-repair or under-repair.

5. The induction repair method of thermoplastic composite material reinforced with carbon nanotubes (CNTs) according to claim 1, characterized in that: The method comprises the following steps: Step 1: Pour the dispersed carbon nanotubes and thermoplastic composite material into the feeding port of the mixer. Step 2: Turn on the power of the industrial control center (3), obtain the morphological features of the interface to be repaired through the three-dimensional scanning camera (14), and feed it back to the industrial control center (3), obtain the repair plan by analyzing the model data of the area to be repaired, and transmit the repair plan to the entire repair system. Step three, according to the obtained repair plan, use the induction heating control system (5) and the infrared temperature measuring instrument (7) to set the appropriate temperature, spinning speed and induction heating frequency. Step 4, turn on the nozzle heating system, spraying system and monitoring system, and according to the established repair plan, control the six-axis robot machine (8) to complete the repair work on the established repair path until the area to be repaired of the workpiece is completely repaired.

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