CN113122183A - Aqueous impregnation liquid for high-power honeycomb wave-absorbing material and preparation method thereof - Google Patents
Aqueous impregnation liquid for high-power honeycomb wave-absorbing material and preparation method thereof Download PDFInfo
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- CN113122183A CN113122183A CN201911412571.5A CN201911412571A CN113122183A CN 113122183 A CN113122183 A CN 113122183A CN 201911412571 A CN201911412571 A CN 201911412571A CN 113122183 A CN113122183 A CN 113122183A
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- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
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Abstract
The invention discloses an aqueous impregnation liquid for a high-power honeycomb wave-absorbing material and a preparation method thereof, wherein the impregnation liquid comprises distilled water, silicone-acrylic resin, a mixture of carbon black and graphite, aluminum hydroxide and a halogen-containing flame retardant synergistic flame retardant, a dispersing agent, a defoaming agent and trihydroxymethyl ethane, and the preparation method comprises the following steps: 1) the preparation method comprises the following steps of (1) preparing impregnation liquid, 2) uniformly stirring and grinding, 3) treating a honeycomb core material, 4) performing first honeycomb impregnation, 5) performing second honeycomb impregnation, and 6) assembling pyramid, wherein the preparation method has the beneficial technical effects that: the power resistance and the service time limit of the honeycomb wave-absorbing material are effectively improved, so that the purpose of prolonging the service life is achieved, the medium-low frequency absorption performance of the honeycomb pyramid is improved to a certain extent, and the absorption performance of the honeycomb wave-absorbing pyramid is improved.
Description
Technical Field
The invention relates to an impregnation liquid and a preparation method thereof, in particular to an aqueous impregnation liquid for a high-power honeycomb wave-absorbing material and a preparation method thereof.
Background
The honeycomb material is a composite material core material invented based on the bionics principle, has extremely low surface density, simultaneously has extremely high strength in the honeycomb axial direction, and can reduce the weight of the material to the maximum extent on the premise of meeting the structural strength. Meanwhile, along with the development of electronic technology, higher and higher requirements are provided for corresponding testing technology, the power of a tested object is improved, the testing time is prolonged, and meanwhile, the heat generated by the wave absorption material in a darkroom due to the absorption of electromagnetic waves is also greatly improved. The aramid paper honeycomb has relatively excellent heat resistance, and meanwhile, due to the porous structure, airflow can be utilized to the maximum extent for heat dissipation, so that the power density which can be responded by the material is greatly improved. The wave-absorbing pyramid with light weight, high strength, excellent wave-absorbing performance and high power resistance has become a research hotspot in recent years. The wave absorbing mechanism of the honeycomb wave absorbing material can be described as follows: electromagnetic waves are scattered and absorbed for many times in a cavity formed by the small honeycomb holes, electromagnetic wave energy is attenuated to the maximum extent, and broadband wave absorbing performance is obtained.
The wave absorbing performance of the honeycomb wave absorbing material is influenced by the thickness, the aperture and the aperture density of the honeycomb plate without considering the influence of the size of the pyramid, and is mainly dependent on the thickness of the wave absorbing layer and the content of the wave absorbing agent. The best wave-absorbing performance is an important target for selecting an immersion liquid system under the condition of controlling the weight gain proportion, and on the other hand, the honeycomb structure can be effectively utilized for heat dissipation, so that the power resistance of the wave-absorbing pyramid is improved to the maximum extent.
The phase-change material can absorb a large amount of heat when phase change occurs, so that the effect of controlling the temperature of a system is achieved. The problem of the prior art is how to control the working temperature of the material within a desired temperature and keep the temperature stable for a certain period of time.
Disclosure of Invention
The invention aims to provide an aqueous impregnation liquid for a high-power honeycomb wave-absorbing material and a preparation method of the high-power honeycomb pyramid wave-absorbing material, which solve the defects in the prior art.
The invention is realized by adopting the following technical scheme:
the aqueous impregnation liquid for the high-power honeycomb wave-absorbing material is characterized by comprising the following components in parts by mass: 80-100 parts of distilled water, 130-150 parts of silicone-acrylic resin, 9-11 parts of a carbon black and graphite mixture, 5-10 parts of a synergistic flame retardant of aluminum hydroxide and a halogen-containing flame retardant, 2.8-4 parts of a dispersing agent 750W, 0.1-0.3 part of a defoaming agent and 10-20 parts of trihydroxymethyl ethane, wherein the carbon-based wave absorbing agent is mixed fine powder of carbon black and graphite, is very loose and has very low apparent density.
A preparation method of a high-power honeycomb pyramid wave-absorbing material is characterized by comprising the following steps:
1) preparing a steeping fluid: mixing the following components in parts by mass: 80-100 parts of distilled water, 130-150 parts of silicone-acrylic resin, 9-11 parts of a carbon black and graphite mixture, 5-10 parts of a synergistic flame retardant of aluminum hydroxide and a halogen-containing flame retardant, 2.8-4 parts of a dispersing agent 750W, 0.1-0.3 part of a defoaming agent and 10-20 parts of trihydroxymethyl ethane;
2) uniformly stirring and grinding, filtering the slurry by using a 120-300 mesh screen and adding the slurry into the mixture;
3) treating a honeycomb core material: cutting the honeycomb into pyramid splicing parts with chamfers by using a vertical saw and a triaxial processing system, processing a whole honeycomb flat plate, cleaning dust on the honeycomb parts by using clean water, and blowing off the surface by connecting an air compressor with a no-load spray gun;
4) first honeycomb impregnation: soaking the honeycomb plate obtained in the step 1) and the honeycomb plate obtained in the step 3) in a soaking tank, fully soaking and fishing out, airing in air and drying;
5) second honeycomb impregnation: soaking the honeycomb plate obtained in the step 1) and the honeycomb plate obtained in the step 4) in a soaking tank, fully soaking and fishing out, airing in air and drying;
6) assembling a pyramid: the honeycomb-shaped plate is assembled into a honeycomb shape in a matching way according to plates, high-temperature epoxy glue is used for coating in a certain glue brushing direction to be adhered at a joint, and the curing is divided into three stages: and (3) waiting for stable bonding at normal temperature, quickly curing at high temperature, and standing at normal temperature to ensure the curing depth.
Further, in the step 1), the silicone-acrylic resin is 110-140 parts by mass.
Further, the plate drying conditions in the step 4) and/or the step 5) are as follows: drying at room temperature for more than 10h, and oven drying at 80 deg.C for more than 1h to completely dry.
Further, the glue brushing direction in the step 6) is as follows: the honeycomb surface which faces outwards after splicing is taken as the bottom, the vertex angle direction is taken as the front, and the motion in the glue brushing direction simultaneously comprises downward motion components and forward motion components.
Further, the curing mode in the step 6) is as follows: and (3) after the structure is stable at normal temperature, sending the mixture into an oven for curing at 80 ℃ for 1h to reach a stable state, and standing the mixture at normal temperature for more than one night to reach the curing depth.
The beneficial technical effects of the invention are as follows: the power resistance and the service time limit of the honeycomb wave-absorbing material are effectively improved, so that the purpose of prolonging the service life is achieved, the medium-low frequency absorption performance of the honeycomb pyramid is improved to a certain extent, and the absorption performance of the honeycomb wave-absorbing pyramid is improved.
Drawings
FIG. 1 is a flow chart of the operation of the present invention.
Detailed Description
The invention will be better understood by the following description of embodiments thereof, but the applicant's specific embodiments are not intended to limit the invention to the particular embodiments shown, and any changes in the definition of parts or features and/or in the overall structure, not essential changes, are intended to define the scope of the invention.
An aqueous impregnation liquid for a high-power honeycomb wave-absorbing material comprises the following components in parts by mass: 80-100 parts of distilled water, 130-150 parts of silicone-acrylic resin, 9-11 parts of a carbon black and graphite mixture, 5-10 parts of a synergistic flame retardant of aluminum hydroxide and a halogen-containing flame retardant, 2.8-4 parts of a dispersing agent 750W, 0.1-0.3 part of a defoaming agent and 10-20 parts of trihydroxymethyl ethane, wherein the carbon-based wave absorbing agent is mixed fine powder of carbon black and graphite, is very loose and has very low apparent density.
A preparation method of a high-power honeycomb pyramid wave-absorbing material is characterized by comprising the following steps:
1) preparing a steeping fluid: the mixture ratio of the components according to claim 1 is as follows: 80-100 parts of distilled water, 130-150 parts of silicone-acrylic resin, 9-11 parts of a carbon black and graphite mixture, 5-10 parts of a synergistic flame retardant of aluminum hydroxide and a halogen-containing flame retardant, 2.8-4 parts of a dispersing agent 750W, 0.1-0.3 part of a defoaming agent and 10-20 parts of trihydroxymethyl ethane;
2) uniformly stirring and grinding, filtering the slurry by using a 120-300 mesh screen and adding the slurry into the mixture;
3) treating a honeycomb core material: cutting the honeycomb into pyramid splicing parts with chamfers by using a vertical saw and a triaxial processing system, processing a whole honeycomb flat plate, cleaning dust on the honeycomb parts by using clean water, and blowing off the surface by connecting an air compressor with a no-load spray gun;
4) first honeycomb impregnation: soaking the honeycomb plate obtained in the step 1) and the honeycomb plate obtained in the step 3) in a soaking tank, fully soaking and fishing out, airing in air and drying;
5) second honeycomb impregnation: soaking the honeycomb plate obtained in the step 1) and the honeycomb plate obtained in the step 4) in a soaking tank, fully soaking and fishing out, airing in air and drying;
6) assembling a pyramid: the honeycomb is assembled by matching plates, and high-temperature epoxy glue is coated on the joint in a certain glue brushing direction for bonding. The curing is divided into three stages: and (3) waiting for stable bonding at normal temperature, quickly curing at high temperature, and standing at normal temperature to ensure the curing depth.
In step 1) of this embodiment, the silicone-acrylic resin is 110 to 140 parts by mass, and the conditions for drying the plate in step 4) and/or step 5) are as follows: drying for more than 1h at 80 ℃ in an oven after drying for more than 10h at normal temperature to achieve complete drying, wherein the glue brushing direction in the step 6) is as follows: the honeycomb surface which faces outwards after splicing is used as the bottom, the vertex angle direction is front, the movement of the glue brushing direction simultaneously comprises downward and forward movement components, and the curing mode in the step 6) is as follows: and (3) after the structure is stable at normal temperature, sending the mixture into an oven for curing at 80 ℃ for 1h to reach a stable state, and standing the mixture at normal temperature for more than one night to reach the curing depth.
The high power honeycomb of this embodiment is inhaled ripples pyramid is formed by the concatenation of high power honeycomb wave-absorbing material plate, including the fire-retardant coating of inhaling of ripples on honeycomb core and surface, the honeycomb unit is the hexagon, and the flooding is by inhaling the wave coating on the honeycomb wall, and it comprises following component to inhale the wave coating:
80-100 parts of distilled water, 110-140 parts of silicone-acrylic resin, 9-11 parts of a carbon black and graphite mixture, 5-10 parts of a synergistic flame retardant of aluminum hydroxide and a halogen-containing flame retardant, 2.8-4 parts of a dispersing agent 750W, 0.1-0.3 part of a defoaming agent, and 10-20 parts of carbon black, wherein the carbon black is a very loose fine powder with an extremely low apparent density of 50% of a compressed product.
The main component of the graphite emulsion is micro-powder graphite, which has conductivity, corrosion resistance and high temperature resistance.
The preparation process of the high-power-resistant honeycomb wave-absorbing pyramid mainly comprises the following steps:
1) raw material preparation and experimental equipment preparation: according to the requirements, distilled water, silicone-acrylic resin, carbon black, graphite, aluminum hydroxide, a halogen-containing flame retardant, a dispersant of 750W, a defoaming agent, trihydroxymethyl ethane and a corresponding honeycomb plate are prepared, a grinder and a balance are needed to be arranged in experimental equipment, and the experimental equipment is needed to be in a perfect clean state and in a normal maintenance state.
2) Preparing a coating: weighing the components (except the silicone-acrylic resin and the defoaming agent) according to the formula, adding the components into a container, uniformly stirring every time one component is added, and finally grinding by using a grinding machine, wherein the grinding speed is gradually increased from low to high, the initial speed can be 500r/min, and is gradually increased to 2000r/min, and the grinding time is 2 hours. And filtering the slurry by adopting a 120-300 mesh screen. Adding silicone-acrylic resin and a defoaming agent according to the formula, and sanding for 30min by using a vertical sand mill at the rotating speed of 500 r/min.
3) Treating a honeycomb core material: cutting a whole honeycomb plate into corresponding shapes according to design requirements, cleaning the honeycomb plate by using flowing clear water, then blowing the honeycomb surface clean by using an air gun, and weighing the mass.
4) Honeycomb impregnation: and pouring the coating A into the dipping tank, horizontally placing the honeycomb material in the dipping tank, and slightly moving the honeycomb plate by using tweezers to fully dip the honeycomb plate. And taking out the soaked solution, simply draining and weighing, and ensuring that the weight is increased by more than one and five times. And then placing the impregnated honeycomb plate on a steel wire frame, airing overnight (more than 10 h), taking back and storing, and drying the honeycomb plate for 1h at 80 ℃ by using an oven.
5) Secondary impregnation of the honeycomb: and pouring the coating B into the dipping tank, horizontally placing the honeycomb material in the dipping tank, and slightly moving the honeycomb plate by using tweezers to fully dip the honeycomb plate. And taking out the soaked solution, simply draining and weighing, and ensuring that the weight is increased by more than one time. And then placing the soaked honeycomb plate on a steel wire frame, airing for one night (more than 10 h), and taking back and storing.
6) And (3) pyramid assembly: placing the honeycomb plate in an oven at 80 ℃ for drying for one hour before assembly, coating high-temperature-resistant epoxy glue on the joint of the dried honeycomb plate, and ensuring the glue brushing amount and simultaneously preventing honeycomb pores in the glue brushing direction so as to ensure the heat exchange efficiency of air passing through the material. And adhering the assembled honeycomb pyramid on a wave-absorbing honeycomb plate serving as a base.
The average temperature during airing is about 26 ℃, and if the temperature is low, a proper extension time is needed. Practical tests show that the temperature rising speed of the wave-absorbing pyramid is obviously reduced when the wave-absorbing pyramid works at low temperature, the time for reaching the equilibrium temperature is longer, the working time under the original design power can be longer, and higher power can be endured in a short time.
Test data (4kW) comparison:
1) temperature rise rate: under the condition of room temperature to 100 ℃, the time required for adding the phase change component (A) is 61.2 seconds, and the time required for adding the phase change component (B) is 78.5 seconds;
2) temperature equilibration time: the time for the group A to reach the equilibrium temperature is about 40min, the temperature slowly rises after 110min, the time for the group B to reach the equilibrium temperature is about 45min, and the rising trend does not appear when 120 min;
3) equilibrium temperature: the balance temperature of the group B is 30-40 ℃ lower than that of the group A in the test time (120 min);
4) absorption performance: the absorption performance of 2-4 GHz is improved by 5-8 dB compared with that of a single-layer coating (without adding trihydroxymethyl ethane).
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore intended that all such changes and modifications as fall within the true spirit and scope of the invention be considered as within the following claims.
Claims (6)
1. The aqueous impregnation liquid for the high-power honeycomb wave-absorbing material is characterized by comprising the following components in parts by mass: 80-100 parts of distilled water, 130-150 parts of silicone-acrylic resin, 9-11 parts of a carbon black and graphite mixture, 5-10 parts of a synergistic flame retardant of aluminum hydroxide and a halogen-containing flame retardant, 2.8-4 parts of a dispersing agent 750W, 0.1-0.3 part of a defoaming agent and 10-20 parts of trihydroxymethyl ethane.
2. A preparation method of a high-power honeycomb pyramid wave-absorbing material is characterized by comprising the following steps:
1) preparing a steeping fluid: mixing the following components in parts by mass: 80-100 parts of distilled water, 130-150 parts of silicone-acrylic resin, 9-11 parts of a carbon black and graphite mixture, 5-10 parts of a synergistic flame retardant of aluminum hydroxide and a halogen-containing flame retardant, 2.8-4 parts of a dispersing agent 750W, 0.1-0.3 part of a defoaming agent and 10-20 parts of trihydroxymethyl ethane;
2) uniformly stirring and grinding, filtering the slurry by using a 120-300 mesh screen and adding the slurry into the mixture;
3) treating a honeycomb core material: cutting the honeycomb into pyramid splicing parts with chamfers by using a vertical saw and a triaxial processing system, processing a whole honeycomb flat plate, cleaning dust on the honeycomb parts by using clean water, and blowing off the surface by connecting an air compressor with a no-load spray gun;
4) first honeycomb impregnation: soaking the honeycomb plate obtained in the step 1) and the honeycomb plate obtained in the step 3) in a soaking tank, fully soaking and fishing out, airing in air and drying;
5) second honeycomb impregnation: soaking the honeycomb plate obtained in the step 1) and the honeycomb plate obtained in the step 4) in a soaking tank, fully soaking and fishing out, airing in air and drying;
6) assembling a pyramid: the honeycomb-shaped plate is assembled into a honeycomb shape in a matching way according to plates, high-temperature epoxy glue is used for coating in a certain glue brushing direction to be adhered at a joint, and the curing is divided into three stages: and (3) waiting for stable bonding at normal temperature, quickly curing at high temperature, and standing at normal temperature to ensure the curing depth.
3. The preparation method of the high-power honeycomb pyramid wave-absorbing material according to claim 2, wherein in the step 1), the silicone-acrylic resin is 110-140 parts by mass.
4. The preparation method of the high-power honeycomb pyramid wave-absorbing material according to claim 2, wherein the conditions for drying the plate in the step 4) and/or the step 5) are as follows: drying at room temperature for more than 10h, and oven drying at 80 deg.C for more than 1h to completely dry.
5. The preparation method of the high-power honeycomb pyramid wave-absorbing material according to claim 2, wherein the glue brushing direction in step 6) is as follows: the honeycomb surface which faces outwards after splicing is taken as the bottom, the vertex angle direction is taken as the front, and the motion in the glue brushing direction simultaneously comprises downward motion components and forward motion components.
6. The preparation method of the high-power honeycomb pyramid absorbing material according to claim 2, wherein the curing mode in step 6) is as follows: and (3) after the structure is stable at normal temperature, sending the mixture into an oven for curing at 80 ℃ for 1h to reach a stable state, and standing the mixture at normal temperature for more than one night to reach the curing depth.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114801336A (en) * | 2022-04-02 | 2022-07-29 | 芜湖创联新材料科技有限公司 | Wave-absorbing honeycomb capable of preventing surface cracking and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106947349A (en) * | 2017-04-06 | 2017-07-14 | 南京南大波平电子信息有限公司 | A kind of aqueous honeycomb Wave suction composite material and preparation method thereof |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106947349A (en) * | 2017-04-06 | 2017-07-14 | 南京南大波平电子信息有限公司 | A kind of aqueous honeycomb Wave suction composite material and preparation method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114801336A (en) * | 2022-04-02 | 2022-07-29 | 芜湖创联新材料科技有限公司 | Wave-absorbing honeycomb capable of preventing surface cracking and preparation method thereof |
| CN114801336B (en) * | 2022-04-02 | 2023-05-23 | 芜湖创联新材料科技有限公司 | Wave-absorbing honeycomb capable of preventing surface cracking and preparation method thereof |
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