Method of making and curing device for low residual stress interlaminar hybrid composite components

Abstract

The application discloses a preparation method and device of a low-residual-stress interlaminar hybrid composite component, and the preparation method comprises the following steps: sealing an interlaminar hybrid composite component on a mold; fixing the sealed component on a vibration test platform; heating and heat-preserving the interlaminar hybrid composite component on the vibration test platform, and applying mechanical vibration and ultrasonic vibration in the process; rapidly cooling and secondarily heating the interlaminar hybrid composite component, and completing subsequent solidification of the interlaminar hybrid composite component. The application introduces wideband high-energy mechanical vibration in the thickness direction of the component, so as to accelerate the escape speed of large-size bubbles, effectively suppresses defects such as pores and delamination, adds ultrasonic vibration along the in-plane direction of the component, uses cavitation effect generated by the ultrasonic field to reduce micro-bubbles, further makes up incompleteness of pore reduction caused by only mechanical vibration, and finally improves thermal mismatch effect between heterogeneous materials through rapid temperature change, and releases residual stress.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of curing molding technology of interlaminar hybrid composite material, and particularly relates to a preparation method and a curing device of interlaminar hybrid composite material component with low residual stress. BACKGROUND

[0002] Interlaminar hybrid composite material is a new type of composite material developed on the basis of advanced composite material, which is made of two or more than two fibers as reinforcing materials and the same resin matrix. It is widely used in aerospace and other fields due to its simple preparation, superior functional diversity, low comprehensive manufacturing cost, low maintenance rate and many other advantages. During the curing process of interlaminar hybrid composite material parts, due to the mismatch of thermal expansion coefficients between different fiber systems and between fibers and resin, as well as the chemical shrinkage of resin, a large amount of curing residual stress will be generated in the component, and the large residual stress will cause deformation of the component and affect its mechanical properties.

[0003] Fast temperature change is one of the effective means to improve the thermal mismatch effect between heterogeneous materials and improve the forming precision of components. During the forming process of interlaminar hybrid composite material parts, the temperature is raised to the gel point temperature of the resin matrix, the parts are cooled to room temperature at a rate of 10~20℃ / min, and then the parts are heated to the curing temperature to complete the subsequent curing reaction. At this time, the resin matrix produces a viscoelastic mutation to release residual stress, resulting in a second reconstruction of the bonding temperature between carbon / glass fiber-resin and each direction layer, reducing the temperature gradient of the part and the demolding temperature, thereby reducing the residual stress caused by the thermal mismatch effect between heterogeneous materials without changing the material system, and improving the profile precision of the formed part. However, the research on fast temperature change curing process is usually carried out in a vacuum negative pressure or pressureless manufacturing environment, which is difficult to match with the high pressure manufacturing demand in a hot press tank, and cannot effectively eliminate defects such as porosity and delamination caused by the lack of curing pressure. Therefore, under the condition of fast temperature change process only, it is difficult to realize the formability and performance synergy of high-performance interlaminar hybrid composite material due to the unattainable pressure.

[0004] When interlaminar hybrid composite material is not cured in a hot press tank, if a high-precision interlaminar hybrid composite material curing component with low defects and low curing residual stress under high pressure curing of the hot press forming process can be obtained, it is a problem that needs to be solved by those skilled in the art. Therefore, those skilled in the art need to develop a device and method for curing high-performance interlaminar hybrid composite material components. SUMMARY

[0005] The present application aims to provide a method for preparing a low-residual-stress interlaminar hybrid composite component, so as to solve the problems of porosity and delamination of low-pressure cured interlaminar hybrid composites and curing residual stress caused by the mismatch of thermal expansion coefficients between different media.

[0006] To achieve the above-mentioned purpose, the present application provides a method for preparing a low-residual-stress interlaminar hybrid composite component, comprising the following steps:

[0007] 1) sealing the interlaminar hybrid composite workpiece to be processed on a mold by using a vacuum bag;

[0008] 2) fixing the sealed interlaminar hybrid composite workpiece and the mold as a whole on a mechanical vibration test platform located in a curing oven;

[0009] 3) heating the interlaminar hybrid composite workpiece to be processed from room temperature to a first temperature at a first heating rate by using an electric heating element and keeping it at the first temperature; in the first heating process, the interlaminar hybrid composite workpiece to be processed is subjected to mechanical vibration in the thickness direction by the mechanical vibration test platform; and in a specified period of time of the first keeping, the interlaminar hybrid composite workpiece to be processed is subjected to ultrasonic vibration transmitted in the in-plane direction by an ultrasonic vibration auxiliary device;

[0010] 4) after the first keeping, first rapidly cooling the interlaminar hybrid composite workpiece processed in the step 3) from the first temperature to room temperature, then heating the rapidly cooled interlaminar hybrid composite workpiece from room temperature to a second temperature at a second heating rate by using an electric heating element and keeping it at the second temperature, and finally obtaining a cured interlaminar hybrid composite component after cooling with the oven;

[0011] wherein the second heating rate is greater than the first heating rate, and the second temperature is higher than the first temperature; the steps 1) to 4) are all subjected to vacuumizing treatment by a vacuumizing device on the vacuum bag, so that the interlaminar hybrid composite workpiece is always in a vacuum negative pressure state throughout the process.

[0012] Further, in the step 2), the interlaminar hybrid composite workpiece to be processed is fixed on the mechanical vibration test platform by using a pressing strip through a bolt connection method to prevent vibration transmission distortion.

[0013] Further, in the step 3), the interlaminar hybrid composite workpiece to be processed is subjected to first heating by using an electric heating element, and the specific process parameters are as follows: the first heating rate is 1.2℃ / min-1.8℃ / min; the first temperature is 120℃-150℃; and the time of the first keeping is 20min-35min.

[0014] Further, in the step 3), the mechanical vibration acceleration is 5g-20g, g=9.8m / s; the mechanical vibration duration is the whole process of the first heating.

[0015] Further, in the step 3), 40s-50s of ultrasonic vibration is added within the first 1min after the beginning of the first holding, the ultrasonic vibration power is 300W-800W, and the ultrasonic amplitude percentage is 40%.

[0016] Further, in the step 4), the rapid cooling is to use liquid nitrogen to rapidly reduce the layer inter-hybrid composite material product after the step 3) from the first temperature to room temperature at a cooling rate of 10℃ / min-12℃ / min, the second heating is to heat the layer inter-hybrid composite material product to 180℃-250℃ at a heating rate of 10℃ / min-12℃ / min, and the second holding time is 135min-160min. The rapid cooling adopted by the present application is to reduce the temperature by the principle of liquid nitrogen vaporization heat absorption. Nitrogen is light and has small density, and will not cause pressure to the product to be cooled. Under normal pressure, the boiling point of liquid nitrogen is-196.56℃, when the passageway between the liquid nitrogen tank and the curing box is opened, the curing temperature is 130℃, and the refrigeration temperature difference can reach 300℃, so the liquid nitrogen will quickly absorb heat and convert into nitrogen gas, and the refrigeration speed is very fast, and the product temperature can be reduced to the target temperature in a short time. When the temperature reaches room temperature, the passageway between the liquid nitrogen tank and the curing box is closed.

[0017] Further, the porosity of the obtained layer inter-hybrid composite material member is 0.26%-0.28%, the curing residual stress is-14.5MPa--15.3MPa, the bending strength is 365MPa-420MPa, and the profile accuracy error is 0.2mm-0.35mm.

[0018] The application further provides a curing device for the preparation method of the low-residual-stress interlaminar hybrid composite component, which comprises an electric heating element, a vacuum bag, a curing box, a rapid cooling device, a mechanical vibration device, an ultrasonic vibration auxiliary device, a vacuumizing device and a mold, the rapid cooling device comprises a liquid nitrogen tank arranged outside the curing box, the liquid nitrogen tank is communicated with the curing box through a nitrogen pipe and is used for conveying liquid nitrogen into the curing box, the mechanical vibration device comprises a mechanical vibration experiment platform horizontally arranged in the curing box, the mechanical vibration experiment platform is used for placing the mold, the vacuum bag is used for sealing the interlaminar hybrid composite component to be processed on the mold, the ultrasonic vibration auxiliary device comprises an ultrasonic vibration head, a transducer and an ultrasonic generator, the ultrasonic vibration head is arranged in the vacuum bag, the transducer is arranged in the curing box and is led out to the outside of the curing box at one end and is connected with the ultrasonic generator, the vacuumizing device is communicated with the vacuum bag through a vacuum pipe and is used for timely extracting the gas generated in the curing process of the interlaminar hybrid composite material to be processed, the electric heating element is used for heating air and then heating the sealed interlaminar hybrid composite material as a whole, the mechanical vibration experiment platform can provide the interlaminar hybrid composite material with vibration with a frequency of 5000 Hz or below and a vibration acceleration of 2g or above, and the ultrasonic vibration auxiliary device can provide the interlaminar hybrid composite material with ultrasonic waves with an ultrasonic power of 1000 W or below, an output frequency of 20 kHz and an amplitude percentage of 20% to 100%.

[0019] Further, the curing box is provided with a gas storage tank outside, each corner of the bottom of the mechanical vibration experiment platform is provided with a vibration spring, and the bottom of the mechanical vibration experiment platform is provided with a plurality of air hammers, and each air hammer is communicated with the gas storage tank through a gas supply pipe.

[0020] Further, the side wall of the curing box is provided with a hot air outlet and a cold air outlet above the mechanical vibration experiment platform, the hot air outlet is connected with the electric heating element through a hot air pipe, and the cold air outlet is communicated with the liquid nitrogen tank through the nitrogen pipe; and the electric heating element adopts a nichrome heating wire heater.

[0021] Compared with the prior art, the application has the following beneficial effects:

[0022] (1) The preparation method of the low-residual-stress interlaminar hybrid composite component, which combines mechanical vibration and ultrasonic vibration in space to form multi-dimensional vibration, and uses multi-dimensional vibration pretreatment to reduce the porosity of the product, and reduces the solidification residual stress by rapid temperature change after the first holding to obtain a low-residual-stress high-performance interlaminar hybrid composite component. The present application firstly introduces 10-2000Hz wide-band high-energy mechanical vibration in the thickness direction of the product to accelerate the escape speed of large-size bubbles, thereby effectively inhibiting defects such as 50-500μm pores and delamination; then adds ultrasonic vibration along the in-plane direction of the product, and uses the cavitation effect generated by the ultrasonic field to eliminate 5-50μm micro-bubbles, thereby further making up the incompleteness of the pore reduction range caused by mechanical vibration alone; finally, the combination temperature between different layers of the composite material and between the fibers and the resin is reduced by rapid temperature change, the difference between the actual combination temperature and the room temperature is reduced, and the temperature gradient of the cooling stage is reduced, thereby improving the thermal mismatch effect between heterogeneous materials and releasing residual stress.

[0023] (2) The preparation device of the low-residual-stress interlaminar hybrid composite component, which is provided with a mechanical vibration device and an ultrasonic vibration auxiliary device, and realizes a preparation method of a low-residual-stress interlaminar hybrid composite component by using the preparation device, i.e. realizes a new method of multi-dimensional vibration-rapid temperature change combined regulation of interlaminar hybrid composite component shape and performance. On the one hand, without changing the existing interlaminar hybrid composite material system, the thermal mismatch effect between carbon / quartz fiber-resin and each layer in the product is improved by rapid temperature change, the solidification residual stress of the product is reduced, and the forming precision is improved; on the other hand, the mechanical vibration along the thickness direction of the product and the ultrasonic vibration along the in-plane direction are comprehensively applied to form a multi-dimensional vibration field, the compaction effect of the interlaminar hybrid composite product and the wettability of the resin to the carbon / quartz fiber are strengthened, the wettability of the fiber to the resin is better, the combination of the quartz fiber and the carbon fiber with the resin in the interlaminar hybrid composite product is more compact, the inhibition of the two fibers to the resin expansion is increased, and the defects such as pores and delamination in the product are effectively eliminated. The low-residual-stress interlaminar hybrid composite component is prepared by using the device, and the multi-dimensional vibration-rapid temperature change forming method combining the two methods weakens the thermal expansion coefficient mismatch effect between the media, effectively reduces the pores and delamination defects of the product under low-pressure curing conditions, reduces the final solidification residual stress, and realizes the shape and performance collaborative manufacturing of the interlaminar hybrid composite product.

[0024] In addition to the objects, features, and advantages described above, the present application has other objects, features, and advantages. The present application will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings are included to provide a further understanding of embodiments of the application, and are incorporated in and constitute a part of this specification, illustrate embodiments of the application, and together with the description serve to explain embodiments of the application, but do not limit the application. In the drawings:

[0026] Fig. 1 is a process flow diagram of a method for preparing a low-residual-stress interlaminar hybrid composite component of the application;

[0027] Fig. 2 is a structural diagram of a curing device for a low-residual-stress interlaminar hybrid composite component of the application;

[0028] Fig. 3 is a schematic diagram of the placement position of an interlaminar hybrid composite component in the application;

[0029] wherein 1 is an interlaminar hybrid composite component, 2 is a vacuum bag, 21 is a vacuum pumping device, 22 is a vacuum pipe, 3 is a curing box, 31 is a hot air outlet, 32 is a cold air outlet, 41 is a liquid nitrogen tank, 42 is a nitrogen pipe, 5 is a mechanical vibration test platform, 51 is an air storage tank, 52 is an air supply pipe, 53 is a small air hammer, 54 is a large air hammer, 55 is a vibration spring, 61 is an ultrasonic horn, 62 is a transducer, 63 is an ultrasonic generator, 7 is a display platform, and 8 is a control cabinet. DETAILED DESCRIPTION

[0030] The embodiments of the application are described in detail below with reference to the accompanying drawings, but the application can be implemented in various different ways as limited and covered by the claims.

[0031] Please refer to Figs. 1 to 3 The method for preparing a low-residual-stress interlaminar hybrid composite component of the embodiments of the application includes the following specific implementation steps:

[0032] 1. The interlaminar hybrid composite component 1 to be processed is sealed on a mold using a vacuum bag 2, wherein the interlaminar hybrid composite component 1 to be processed can be selected from ZT7H / 5429 and QW280 / 5429 interlaminar hybrid composite components.

[0033] 2. The sealed interlaminar hybrid composite component 1 and the mold are integrally fixed on a mechanical vibration test platform 5 using a pressing strip to prevent vibration transmission distortion, wherein the pressing strip is connected to the mechanical vibration test platform by a bolt connection mode, and the mechanical vibration test platform is arranged in a curing box.

[0034] 3. The first heating rate of 1.2℃ / min~1.8℃ / min is used to heat the interlaminar hybrid composite material workpiece from room temperature to 120℃~150℃ by using the electric heating element, and the temperature is kept for 20min-35min; wherein, in the first heating process, the mechanical vibration along the thickness direction is applied to the interlaminar hybrid composite material workpiece 1 by the mechanical vibration experiment platform 5, the mechanical vibration acceleration is 5g~20g, g=9.8m / s; the mechanical vibration duration is the whole process of the first heating. After the mechanical vibration, the ultrasonic vibration along the in-plane direction is provided to the interlaminar hybrid composite material workpiece within the first 1min after the first temperature keeping by using the ultrasonic vibration auxiliary device, the ultrasonic vibration power is 300W~800W, the ultrasonic amplitude percentage is 40%, and the duration is 40s~50s.

[0035] 4) After the first temperature keeping, the interlaminar hybrid composite material workpiece treated in step 3) is rapidly cooled and secondly heated; the rapid cooling is to make the interlaminar hybrid composite material workpiece rapidly cooled from 180℃~250℃ to room temperature at the cooling rate of 10℃ / min~12℃ / min by using the principle of rapid heat absorption when liquid nitrogen is converted into nitrogen gas; the second heating is to heat the interlaminar hybrid composite material workpiece treated in step 3) from room temperature to 180℃~250℃ at the heating rate of 10℃ / min~12℃ / min, and then keep the temperature for 135min~160min; finally, the interlaminar hybrid composite material workpiece is cooled in the oven to obtain the cured interlaminar hybrid composite material workpiece.

[0036] In the above steps, the vacuum bag 2 is vacuumized by the vacuumizing device 21, so that the interlaminar hybrid composite material workpiece 1 is always in the vacuum negative pressure state in the whole process. The heating and temperature keeping in the above process are to heat the air by using the nickel-chromium alloy electric heating wire heater, and the heated air is transferred into the curing box through the hot air outlet, and the heating or temperature keeping of the interlaminar hybrid composite material workpiece is carried out by forced convection. The porosity of the interlaminar hybrid composite material workpiece prepared by the method is 0.26%~0.28%, the curing residual stress is -14.5MPa~-15.3MPa, the bending strength is 365MPa~420MPa, and the profile accuracy error is 0.2mm~0.35mm.

[0037] In a specific embodiment, the mechanical vibration experiment platform used in the present application has a vibration frequency range of 0-5000 Hz, with higher energy excitation within 10-2000 Hz; a temperature range of -70-200°C, a maximum vibration acceleration of 70g, an effective working range of the mechanical vibration experiment platform of 0.915m x 0.915m x 1m (length x width x height), and a maximum bearing weight of 145 Kg. The mechanical vibration experiment platform is supported by four fixed vibration springs 55, and a plurality of air hammers are connected to the lower part of the mechanical vibration experiment platform through threaded fastening. An external air compressor is used as a power source to continuously provide stable vibration sources for the mechanical vibration experiment platform by using the air hammers. The vibration excitation is transmitted from the bottom to the top of the workpiece along the thickness direction of the workpiece.

[0038] In a specific embodiment, the ultrasonic vibration auxiliary device used in the present application has an output frequency of 20 kHz ± 1% for the ultrasonic generator 63, an amplitude percentage of 20%-100%, and an output power adjustment range of 0-1000 W. The ultrasonic vibration head 61 of the ultrasonic vibration auxiliary device is fixed in the vacuum bag 2 and in contact with the workpiece, and provides ultrasonic vibration transmitted in the in-plane direction to the interlaminar hybrid composite workpiece.

[0039] Example 1

[0040] The interlaminar hybrid composite material is cured using the preparation method of the present application, and the carbon fiber is ZT7H / 5429 and the quartz fiber is QW280 / 5429.

[0041] After sealing and fastening the interlaminar hybrid composite material, the electric heating element is used for temperature rising and curing treatment of the interlaminar hybrid composite material, and the mechanical vibration table is used for vibration treatment of the workpiece at the same time. The temperature is heated from room temperature to 130°C at a heating rate of 1.5°C / min, and then kept for 30 min. Ultrasonic vibration of 45s is introduced at the beginning of the holding. The mechanical vibration along the thickness direction is applied during the whole heating process, the vibration acceleration is 10g, and the vibration frequency is 10-5000 Hz. Ultrasonic vibration of 45s in the in-plane direction is introduced at the beginning of the holding, the ultrasonic power is 400W, and the output frequency is 20kHz. The interlaminar hybrid composite material is subjected to vacuum treatment during the vibration process.

[0042] After the first holding is completed, the interlaminar hybrid composite workpiece is rapidly cooled at a cooling rate of 10°C / min from 130°C to room temperature, and then is subjected to secondary heating at a heating rate of 10°C / min from room temperature to 200°C and kept for 150 min. The interlaminar hybrid composite workpiece is continuously subjected to vacuum treatment during this stage, and the environmental pressure of the workpiece is 0MPa. After the holding is completed, the interlaminar hybrid composite workpiece is obtained after furnace cooling.

[0043] The porosity of the obtained interlaminar hybrid composite part is 0.27%, the curing residual stress is -14.72 MPa, the bending strength is 376.6 MPa, and the profile accuracy error is 0.273 mm.

[0044] Comparative Example 1

[0045] In this comparative example, the carbon / quartz fiber interlaminar hybrid composite material is cured as a whole by using a hot press tank alone at high temperature and low pressure. The curing pressure is 0 MPa. The temperature of the composite material is raised from room temperature to 130°C at a rate of 1.5°C / min in the electric heating of the hot press tank, and then kept at 130°C for 30 min. Then the temperature is raised to 200°C at a rate of 1.5°C / min, and kept at 200°C for 150 min. After cooling in the furnace, the interlaminar hybrid composite part is obtained. Vacuum treatment is performed on the part during the entire curing process.

[0046] The porosity of the obtained part is 7.44%, the interlaminar shear strength is 54.74 MPa, the curing residual stress is -38.2 MPa, the bending strength is 243.9 MPa, and the profile accuracy error is 0.436 mm.

[0047] Comparative Example 2

[0048] In this comparative example, the carbon / quartz fiber interlaminar hybrid composite material is cured as a whole by using a hot press tank alone at high temperature and high pressure. The curing pressure is 0.6 MPa. The temperature of the composite material is raised from room temperature to 130°C at a rate of 1.5°C / min in the electric heating of the hot press tank, and then kept at 130°C for 30 min. Then the temperature is raised to 200°C at a rate of 1.5°C / min, and kept at 200°C for 150 min. After cooling in the furnace, the interlaminar hybrid composite part is obtained. Vacuum treatment is performed on the part during the entire curing process.

[0049] The porosity of the obtained part is 0.33%, the interlaminar shear strength is 79.91 MPa, the curing residual stress is -17.71 MPa, the bending strength is 389.1 MPa, and the profile accuracy error is 0.264 mm.

[0050] Comparative Example 3

[0051] In this comparative example, the carbon / quartz fiber interlaminar hybrid composite material is cured by using a curing device alone at low pressure by using multi-dimensional vibration pretreatment. The interlaminar hybrid composite material is heated and cured by using an electric heating element, and the part is vibrated by using a vibration table at the same time. The temperature is raised from room temperature to 130°C at a rate of 1.5°C / min, and then kept at 130°C for 30 min. Mechanical vibration is applied along the thickness direction of the part during the entire heating process. The vibration acceleration is 10g, and the vibration frequency is 10-5000 Hz. Vacuum treatment is performed on the interlaminar hybrid composite material during the vibration process.

[0052] After the holding, the interlaminar hybrid composite part is subjected to secondary heating at a heating rate of 1.5 ℃ / min from 130 ℃ to 200 ℃ and is held for 150 min. In this stage, the composite material is continuously subjected to vacuum extraction, and the pressure of the environment in which the composite material is located is 0 MPa. After the holding, the interlaminar hybrid composite part is obtained after furnace cooling.

[0053] The obtained interlaminar hybrid composite material has a porosity of 0.29%, an interlaminar shear strength of 81.29 MPa, a curing residual stress of -24.03 MPa, a bending strength of 358 MPa, and a surface accuracy error of 0.379 mm.

[0054] Comparative Example 4:

[0055] In this comparative example, the carbon / quartz fiber interlaminar hybrid composite material is subjected to low-pressure curing by using a curing device and a rapid temperature change method alone. The interlaminar hybrid composite material is subjected to heating and curing by using an electric heating element, and the temperature is heated from room temperature to 130 ℃ at a heating rate of 1.5 ℃ / min, and then is held for 30 min. In this process, the interlaminar hybrid composite material is subjected to vacuum extraction.

[0056] After the holding, the interlaminar hybrid composite part is subjected to rapid cooling at a cooling rate of 10 ℃ / min from 130 ℃ to room temperature, and then is subjected to secondary heating at a heating rate of 10 ℃ / min from room temperature to 200 ℃ and is held for 150 min. In this stage, the composite material is continuously subjected to vacuum extraction, and the pressure of the environment in which the composite material is located is 0 MPa. After the holding, the interlaminar hybrid composite part is obtained after furnace cooling.

[0057] The obtained interlaminar hybrid composite material has a porosity of 1.7%, an interlaminar shear strength of 69.76 MPa, a curing residual stress of -19.03 MPa, a bending strength of 341 MPa, and a surface accuracy error of 0.388 mm.

[0058] As can be seen from Example 1, Comparative Example 1 and Comparative Example 2, the interlaminar hybrid composite part obtained by the multi-dimensional vibration-rapid temperature change curing method has a large improvement in appearance and performance compared with the part obtained by the autoclave process at a curing pressure of 0 MPa, and has a quality similar to that of the part obtained by the autoclave high-pressure curing forming, and can meet the demand for high-performance interlaminar hybrid composite materials.

[0059] From the comparative example 1, comparative example 2 and comparative example 3, it can be seen that after the introduction of the spatially compounded multi-dimensional vibration, the porosity of the obtained interlaminar hybrid composite part is reduced by 95% relative to the 0 MPa autoclave forming part, and is similar to the porosity of the 0.6 MPa autoclave high-pressure curing forming part. Although the curing residual stress of the part pretreated by vibration is reduced by 37.09% relative to the 0 MPa autoclave forming part, it is still 26.3% higher than the residual stress of the 0.6 MPa autoclave curing forming part.

[0060] From the comparative example 1, comparative example 2 and comparative example 4, it can be seen that under the 0 MPa curing pressure, the interlaminar hybrid composite part obtained only by the rapid temperature change treatment has a morphology and performance far lower than the 0.6 MPa autoclave high-pressure curing forming part, but its porosity is reduced by 77.15% relative to the 0 MPa autoclave forming part, and the curing residual stress is reduced by 50.18%.

[0061] In summary, after the introduction of the spatially compounded multi-dimensional vibration under the low-pressure curing condition, the porosity of the interlaminar hybrid composite part is reduced by a cliff relative to the 0 MPa autoclave forming part, and the curing residual stress is also reduced. On the basis of the multi-dimensional vibration pretreatment, after the first holding is finished, the rapid temperature change is added, the obtained interlaminar hybrid composite part not only has a great improvement in the morphology, but also has a great improvement in the performance, and the quality of the obtained part is close to the quality of the autoclave high-pressure curing forming part, which meets the requirements of the interlaminar hybrid composite part for aerospace use.

[0062] See Fig. 2 and Fig. 3As shown, the present application also provides a curing device for realizing the preparation method of the low residual stress interlaminar hybrid composite component, which comprises an electric heating element, a vacuum bag 2, a curing box 3, a liquid nitrogen tank 41, a mechanical vibration device, an ultrasonic vibration auxiliary device, a vacuumizing device 21, a mold, a display table 7 and a control cabinet 8. The liquid nitrogen tank is arranged outside the curing box 3 and is communicated with the curing box 3 through a nitrogen pipe 42 for conveying liquid nitrogen into the curing box 3. The mechanical vibration device comprises a mechanical vibration experimental platform 5 arranged horizontally in the curing box, which is used for placing the mold. The interlaminar hybrid composite component 1 to be processed is sealed on the mold through the vacuum bag 2. The ultrasonic vibration auxiliary device comprises an ultrasonic vibration head 61, a transducer 62 and an ultrasonic generator 63. The ultrasonic vibration head 61 is arranged in the vacuum bag 2. The transducer 62 is arranged in the curing box 3 and is led out to the outside of the curing box 3 at one end and is connected with the ultrasonic generator 63. The vacuumizing device 21 is connected with the vacuum bag 2 through a vacuum pipe 22 for timely extracting the gas generated in the curing process of the interlaminar hybrid composite component 1 to be processed. The electric heating element heats the sealed interlaminar hybrid composite component 1 as a whole through heated air. The mechanical vibration experimental platform 5 can provide the interlaminar hybrid composite component 1 with vibration of high energy input with a frequency of 5000 Hz or below and vibration acceleration of 2 g or above. The ultrasonic vibration auxiliary device can provide the interlaminar hybrid composite component with ultrasonic waves with an ultrasonic power of 1000 W or below, an output frequency of 20 kHz and an amplitude percentage of 20% to 100%. The control cabinet is connected with the electric heating element, the vacuumizing device, the control device of the liquid nitrogen tank, the mechanical vibration device, the ultrasonic vibration auxiliary device and the display table, etc. for controlling the whole curing device.

[0063] In a specific embodiment, the gas storage tank 51 is arranged outside the curing box 3. The mechanical vibration experimental platform 5 is provided with a vibration spring 55 at each of the four corners of the bottom. The bottom of the mechanical vibration experimental platform is provided with a plurality of air hammers. All the air hammers are communicated with the gas storage tank through a gas supply pipe 52. Specifically, the air hammers comprise a plurality of small air hammers 53 arranged in the middle and a plurality of large air hammers 54 arranged at the two sides of the bottom.

[0064] In a specific embodiment, the side wall of the curing box is provided with a hot air outlet 31 and a cold air outlet 32 above the mechanical vibration experimental platform. The hot air outlet 31 is connected with the electric heating element through a hot air pipe. The cold air outlet is communicated with the liquid nitrogen tank through the nitrogen pipe 42. The electric heating element adopts a nichrome heating wire heater.

[0065] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method of making a low residual stress interlaminar hybrid composite component, characterized by, The method comprises the following steps: 1) sealing the interlaminar hybrid composite part to be processed on a mold by using a vacuum bag; 2) fixing the sealed interlaminar hybrid composite part to be processed and the mold as a whole on a mechanical vibration test platform located in a curing box; 3) heating the interlaminar hybrid composite part to be processed from room temperature to a first temperature at a first heating rate of 1.2-1.8 ℃ / min and keeping the temperature, the first temperature being 120-150 ℃, the first time for keeping the temperature being 20-35 min; during the first heating, the interlaminar hybrid composite part to be processed is subjected to mechanical vibration along the thickness direction by the mechanical vibration test platform, the mechanical vibration acceleration being 5-20 g (g=9.8 m / s), and the mechanical vibration duration being the whole process of the first heating; and within the first 1 min after the start of the first keeping of the temperature, the interlaminar hybrid composite part to be processed is subjected to ultrasonic vibration transmitted along the in-plane direction for 40-50 s by an ultrasonic vibration auxiliary device, the ultrasonic vibration power being 300-800 W, and the ultrasonic amplitude percentage being 40%; 4) after the first keeping of the temperature, the interlaminar hybrid composite part processed in step 3) is rapidly cooled from the first temperature to room temperature by using liquid nitrogen, and then the interlaminar hybrid composite part after the rapid cooling is heated from room temperature to a second temperature at a second heating rate and kept at the second temperature, and finally the interlaminar hybrid composite part is cooled in the furnace to obtain a cured interlaminar hybrid composite part; the second heating rate being 10-12 ℃ / min, the second temperature being 180-250 ℃, the second time for keeping the temperature being 135-160 min, the cooling rate being 10-12 ℃ / min; the porosity of the prepared interlaminar hybrid composite part being 0.26-0.28%, the curing residual stress being -14.5 to -15.3 MPa, the bending strength being 365-420 MPa, and the profile accuracy error being 0.2-0.35 mm; wherein the vacuum bag is subjected to vacuumizing treatment by a vacuumizing device in steps 1) to 4), so that the interlaminar hybrid composite part is always in a vacuum negative pressure state during the whole process. In step 2), the interlaminar hybrid composite part to be processed is fixed on the mechanical vibration test platform by using a pressing strip through a bolt connection mode to prevent vibration transmission distortion.

2. The production method according to claim 1, characterized by, ​ 3. A curing device for realizing the production method of the low residual stress interlaminar hybrid composite member according to claim 1 or 2, characterized by, The application relates to a curing device for interlaminar hybrid composite materials, which comprises an electric heating element, a vacuum bag, a curing box, a rapid cooling device, a mechanical vibration device, an ultrasonic vibration auxiliary device, a vacuumizing device and a mold, wherein the rapid cooling device comprises a liquid nitrogen tank arranged outside the curing box, the liquid nitrogen tank is communicated with the curing box through a nitrogen pipe and is used for conveying liquid nitrogen into the curing box; the mechanical vibration device comprises a mechanical vibration experiment platform horizontally arranged in the curing box, the mechanical vibration experiment platform is used for placing the mold, the vacuum bag is used for sealing the interlaminar hybrid composite material to be processed on the mold, the ultrasonic vibration auxiliary device comprises an ultrasonic vibration head, a transducer and an ultrasonic generator, the ultrasonic vibration head is arranged in the vacuum bag, the transducer is arranged in the curing box and is led out to the outside of the curing box at one end and is connected with the ultrasonic generator; the vacuumizing device is communicated with the vacuum bag through a vacuum pipe and is used for timely extracting the gas generated in the curing process of the interlaminar hybrid composite material; the electric heating element heats air and then heats the sealed interlaminar hybrid composite material as a whole; the mechanical vibration experiment platform can provide the interlaminar hybrid composite material with vibration with high energy input at a frequency of 5000 Hz or below and vibration with vibration acceleration of 2g or above; the ultrasonic vibration auxiliary device can provide the interlaminar hybrid composite material with ultrasonic waves with ultrasonic power below 1000 W, an output frequency of 20 kHz and an amplitude percentage of 20%-100%.

4. The curing device of claim 3, wherein An air storage tank is arranged outside the curing box, a vibration spring is arranged at each of the four corners of the bottom of the mechanical vibration experiment platform, and a plurality of air hammers are arranged at the bottom of the mechanical vibration experiment platform and are communicated with the air storage tank through air supply pipes.

5. The curing device of claim 3, wherein A hot air outlet and a cold air outlet are arranged on the side wall of the curing box and above the mechanical vibration experiment platform, the hot air outlet is connected with the electric heating element through a hot air pipe, the cold air outlet is communicated with the liquid nitrogen tank through the nitrogen pipe, and the electric heating element adopts a nickel-chromium alloy electric heating wire heater.

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