CN111844804B - Microwave curing process and device for fiber winding composite material - Google Patents
Microwave curing process and device for fiber winding composite material Download PDFInfo
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- CN111844804B CN111844804B CN202010698684.2A CN202010698684A CN111844804B CN 111844804 B CN111844804 B CN 111844804B CN 202010698684 A CN202010698684 A CN 202010698684A CN 111844804 B CN111844804 B CN 111844804B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
- B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C33/00—Moulds or cores; Details thereof or accessories therefor
- B29C33/38—Moulds or cores; Details thereof or accessories therefor characterised by the material or the manufacturing process
- B29C33/40—Plastics, e.g. foam or rubber
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
- B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
- B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/54—Component parts, details or accessories; Auxiliary operations, e.g. feeding or storage of prepregs or SMC after impregnation or during ageing
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
- B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
- B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
- B29C2035/0855—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation using microwave
Abstract
A microwave curing process for a fiber winding composite material belongs to the field of composite material manufacturing, and is characterized in that: preparing a fiber winding composite material by adopting a winding mode; placing the prepared fiber winding composite material in a microwave curing device to start microwave curing; the microwave curing process sequentially comprises a heating stage, a curing stage and a cooling stage; a plurality of heat preservation stages are arranged in the temperature rising stage and the curing stage; and in the heat preservation stage, the temperature is stopped rising when the curing temperature rises to a preset temperature value, the curing temperature is maintained within a preset time period, and the temperature is continued rising after the preset time is up. Controlling the initial heating rate in the microwave curing process of the fiber wound composite material, and reducing the porosity of the microwave cured product of the fiber wound composite material; compared with the traditional thermosetting process, the curing period can be shortened by more than 40 percent, and the production cost of the composite material is reduced; improves the quality of the cured product, and is beneficial to promoting the microwave curing to be widely applied to the production and the manufacture of composite materials.
Description
Technical Field
The invention belongs to the field of composite material manufacturing, and particularly relates to a microwave curing process and device for a manufacturing process of a fiber winding composite material.
Background
The fiber reinforced composite material has the characteristics of high specific strength, high specific stiffness, good corrosion resistance and the like, and is widely applied to the fields of aerospace, sports equipment and the like. In the application field with clear revolving body characteristics like a high-pressure gas cylinder, the fiber winding composite material has wide application.
In the traditional composite material manufacturing process, a large amount of energy is wasted due to the adoption of an autoclave curing mode, so that the cost of the composite material is high. In the research of low cost of the composite material, the microwave curing has the outstanding advantages of high hot efficiency, uniform heat transfer and the like, thereby having wide development prospect. However, in the practical application of microwave curing, too fast curing process often results in more pores in the final product, resulting in poor mechanical properties of the material.
Disclosure of Invention
The invention aims to solve the problems and provides a microwave curing process and a microwave curing device for a fiber wound composite material, which can improve the quality of a cured product.
The microwave curing process of the fiber winding composite material comprises the following steps of firstly preparing the fiber winding composite material by adopting a wet method or a dry method winding manner; placing the prepared fiber winding composite material in a microwave curing device to start microwave curing; the microwave curing process sequentially comprises a heating stage, a curing stage and a cooling stage; the temperature rise stage and the curing stage are both provided with a plurality of heat preservation stages; and in the heat preservation stage, the temperature is stopped when the curing temperature rises to a preset temperature value, the curing temperature is maintained within a preset time period, and the temperature is continuously raised after the preset time is up.
The microwave curing process of the fiber winding composite material comprises the following steps:
1) the specific process of the temperature rise stage is as follows: firstly, heating the fiber winding composite material by using 70W of microwave power, stopping heating when the temperature is raised to 40 ℃, keeping the fixed temperature for 10min, and then continuing heating; stopping heating when the temperature is raised to 70 ℃ and keeping the fixed temperature for 10 min;
2) the concrete process of the curing stage is as follows: heating the composite material by using 140W microwave power after the temperature is raised to 70 ℃ of curing temperature and is kept for 10min, stopping heating when the temperature is raised to 90 ℃, keeping the fixed temperature for 5min, and continuing heating; stopping heating when the temperature is raised to 110 ℃ and keeping the fixed temperature for 35 min;
3) the specific process of the cooling stage is as follows: stopping heating when the temperature is raised to 110 ℃, keeping the fixed temperature for 35min, then entering a cooling stage, and stopping heating to naturally cool the temperature of the fiber winding composite material.
The microwave curing process of the fiber winding composite material comprises the following steps:
1) preparing epoxy resin system glue solution according to the proportion at the temperature of 50-70 ℃, uniformly stirring, and pouring into a glue tank;
2) winding a fiber winding composite material with the thickness of 3 +/-0.1 mm on a die by using a numerical control winding machine;
3) standing the wound fiber winding composite material for 3-5h until no glue flowing phenomenon is generated, and finishing the preparation.
The invention relates to a microwave curing process of a fiber winding composite material, wherein a mold is a polytetrafluoroethylene mold.
The invention relates to a microwave curing process of a fiber winding composite material, which comprises the following steps: t700 carbon fiber composite material, bisphenol A type epoxy resin, TDE-85 epoxy resin and mixed aromatic amine curing agent.
The microwave curing device for the microwave curing process of the fiber wound composite material comprises a microwave curing cavity and a PID control system; a glass turntable is arranged in the microwave curing cavity; a winding mould is arranged on the glass turntable; the bottom of the glass turntable is provided with a rotating shaft; a magnetron is arranged on the outer side of the bottom wall of the microwave curing cavity; an infrared probe is arranged on the side wall of the microwave curing cavity; the infrared probe, the PID control system and the magnetron are electrically connected in sequence.
The microwave curing process and the microwave curing device for the fiber wound composite material can control the initial heating rate in the microwave curing process of the fiber wound composite material and reduce the porosity of a microwave cured product of the fiber wound composite material; compared with the traditional thermosetting process, the curing period can be shortened by more than 40 percent, and the production cost of the composite material is reduced; meanwhile, the quality of the cured product is improved, and the microwave curing is promoted to be widely applied to the production and the manufacture of the composite material.
Drawings
FIG. 1 is a schematic view of a microwave curing process curve for a filament wound composite material according to the present invention;
FIG. 2 is a schematic structural view of a microwave curing apparatus for filament wound composite material according to the present invention;
the microwave curing device comprises a magnetron 1, a composite material 2, a polytetrafluoroethylene mold 3, a microwave curing cavity 4, an infrared probe 5, a glass turntable 6, a rotating shaft 7 and a PID control system 8.
Detailed Description
The microwave curing process and apparatus for filament wound composite material according to the present invention will be described in detail with reference to the accompanying drawings and examples.
The microwave curing process of the fiber wound composite material adopts a microwave curing device as shown in figure 2, wherein the microwave curing device comprises a microwave curing cavity 4 and a PID control system 8; a glass rotary table 6 is arranged in the microwave curing cavity 4; a winding mould is arranged on the glass turntable 6; the bottom of the glass rotary table 6 is provided with a rotating shaft 7; a magnetron 1 is arranged on the outer side of the bottom wall of the microwave curing cavity 4; an infrared probe 5 is arranged on the side wall of the microwave curing cavity 4; the infrared probe 5, the PID control system 8 and the magnetron 1 are electrically connected in sequence. The temperature of a test piece of the feedback composite material 2 is measured by an infrared temperature measuring probe, and the microwave output power is controlled by a PID control system 8, so that the heat preservation of the test piece is realized.
Firstly, preparing a fiber winding composite material by adopting a wet method or a dry method winding mode; placing the prepared fiber winding composite material in a microwave curing device to start microwave curing; the microwave curing process sequentially comprises a heating stage, a curing stage and a cooling stage; the temperature rise stage and the curing stage are both provided with a plurality of heat preservation stages; and in the heat preservation stage, the temperature is stopped to rise when the curing temperature rises to a preset temperature value, the fixed temperature is maintained in a preset time period, and the temperature is continued to rise after the preset time is up.
The microwave curing process of the fiber winding composite material disclosed by the invention comprises the following steps of:
1) the specific process of the temperature rise stage is as follows: firstly, heating the fiber winding composite material by using 70W of microwave power, stopping heating when the temperature is raised to 40 ℃, keeping the fixed temperature for 10min, and continuing heating; stopping heating when the temperature is raised to 70 ℃ and keeping the fixed temperature for 10 min;
2) the concrete process of the curing stage is as follows: heating the composite material 2 by using 140W microwave power after the temperature is raised to 70 ℃ of curing temperature and the temperature is kept for 10min, stopping heating when the temperature is raised to 90 ℃, keeping the fixed temperature for 5min and continuing heating; stopping heating when the temperature is raised to 110 ℃ and keeping the fixed temperature for 35 min;
3) the specific process of the cooling stage is as follows: stopping heating when the temperature is raised to 110 ℃, keeping the fixed temperature for 35min, then entering a cooling stage, and stopping heating to naturally cool the temperature of the fiber winding composite material.
The microwave curing process of the fiber winding composite material comprises the following steps:
1) preparing epoxy resin system glue solution according to the proportion at the temperature of 50-70 ℃, uniformly stirring, and pouring into a glue tank; the composition of the filament wound composite material comprises: t700 carbon fiber composite material 2, bisphenol A epoxy resin, TDE-85 epoxy resin and mixed aromatic amine curing agent;
2) winding the fiber winding composite material with the thickness of 3 +/-0.1 mm on a die by using a numerical control winding machine; the mould is a polytetrafluoroethylene mould 3;
3) standing the wound fiber winding composite material for 3-5h until no glue flowing phenomenon is generated, and finishing the preparation.
According to the microwave curing process for the fiber-wound composite material, a plurality of pre-insulation platforms are arranged before the insulation stage of the curing system of the fiber-wound composite material is reached, so that the fiber-reinforced composite material 2 is prevented from being heated too fast due to strong microwave response. In the initial stage of microwave curing, the average heating rate in the heating process is slowed down by controlling the microwave power, and the phenomena of bubble expansion and the like caused by the excessively high heating rate are inhibited. The heat preservation process is controlled by a PID system. And natural cooling is adopted in the cooling stage.
In specific implementation, in the initial temperature rise stage, the composite material 2 is heated by using 70W of microwave power, and when the curing temperature rises to 70 ℃, the composite material 2 is heated by using 140W of microwave power; secondly, in the aspect of curing temperature control, a 'step-type' temperature control measure is adopted to prevent the composite material 2 from heating up too fast. In the temperature rise stage, a plurality of pre-heat preservation platforms are arranged, so that the power of the initial temperature rise stage is effectively controlled, and the influence on the quality of the product due to excessive pores in the product caused by the excessively high temperature rise rate is avoided. In the process of controlling the temperature, the infrared probe 5 measures the surface temperature of the fiber winding composite material test piece, the temperature signal is transmitted to the PID control system 8, the control system outputs control voltage according to the feedback signal, and the output power is changed by controlling the working voltage of the magnetron 1, so that the purpose of heat preservation on a fixed temperature platform is achieved. Tests show that the porosity of the fiber winding composite material cured by the original microwave curing process (without the pre-insulation platform) is 1.68-2.13%; the porosity of the filament wound composite material cured by the improved microwave curing process of the embodiment is 0.82-1.15%.
The foregoing is only a preferred embodiment of the present invention, and it should be understood that modifications made without departing from the principles of the invention are also within the scope of the invention.
Claims (5)
1. A microwave curing process for a fiber-wound composite material is characterized by comprising the following steps: firstly, preparing a fiber winding composite material by adopting a wet method or a dry method winding mode; placing the prepared fiber winding composite material in a microwave curing device to start microwave curing; the microwave curing process sequentially comprises a heating stage, a curing stage and a cooling stage; the method specifically comprises the following steps:
1) the specific process of the temperature rise stage is as follows: firstly, heating the fiber winding composite material by using 70W of microwave power, stopping heating when the temperature is raised to 40 ℃, keeping the fixed temperature for 10min, and continuing heating; stopping heating when the temperature is raised to 70 ℃ and keeping the fixed temperature for 10 min;
2) the concrete process of the curing stage is as follows: heating the composite material by using 140W microwave power after the temperature is raised to 70 ℃ of curing temperature and is kept for 10min, stopping heating when the temperature is raised to 90 ℃, keeping the fixed temperature for 5min, and continuing heating; stopping heating when the temperature is raised to 110 ℃ and keeping the fixed temperature for 35 min;
3) the specific process of the cooling stage is as follows: stopping heating when the temperature rises to 110 ℃, keeping the fixed temperature for 35min, then entering a cooling stage, and stopping heating to naturally cool the temperature of the fiber wound composite material;
the temperature rise stage and the curing stage are both provided with a plurality of heat preservation stages; and in the heat preservation stage, the temperature is stopped to rise when the curing temperature rises to a preset temperature value, the fixed temperature is maintained in a preset time period, and the temperature is continued to rise after the preset time is up.
2. A process for microwave curing of a filament wound composite material according to claim 1 wherein: the process for preparing the fiber winding composite material comprises the following steps:
1) preparing epoxy resin system glue solution according to the proportion at the temperature of 50-70 ℃, uniformly stirring, and pouring into a glue tank;
2) winding a fiber winding composite material with the thickness of 3 +/-0.1 mm on a die by using a numerical control winding machine;
3) standing the wound fiber winding composite material for 3-5h until no glue flowing phenomenon is generated, and finishing the preparation.
3. A process for microwave curing of a filament wound composite material according to claim 2 wherein: the mould is a polytetrafluoroethylene mould.
4. A process for microwave curing of a filament wound composite material according to claim 3 wherein: the composition of the filament wound composite material comprises: t700 carbon fiber composite material, bisphenol A type epoxy resin, TDE-85 epoxy resin and mixed aromatic amine curing agent.
5. A microwave curing apparatus for a microwave curing process of filament wound composite material as in claim 1, wherein: comprises a microwave curing cavity and a PID control system; a glass rotary table is arranged in the microwave curing cavity; a winding mould is arranged on the glass turntable; the bottom of the glass turntable is provided with a rotating shaft; a magnetron is arranged on the outer side of the bottom wall of the microwave curing cavity; an infrared probe is arranged on the side wall of the microwave curing cavity; the infrared probe, the PID control system and the magnetron are electrically connected in sequence;
the PID control system is used for controlling microwave output power in the microwave curing process, and specifically comprises the following steps: 1) the specific process of the temperature rise stage is as follows: firstly, heating the fiber winding composite material by using 70W of microwave power, stopping heating when the temperature is raised to 40 ℃, keeping the fixed temperature for 10min, and continuing heating; stopping heating when the temperature is raised to 70 ℃ and keeping the fixed temperature for 10 min;
2) the concrete process of the curing stage is as follows: heating the composite material by using 140W microwave power after the temperature is raised to 70 ℃ of curing temperature and is kept for 10min, stopping heating when the temperature is raised to 90 ℃, keeping the fixed temperature for 5min, and continuing heating; stopping heating when the temperature is raised to 110 ℃ and keeping the fixed temperature for 35 min;
3) the specific process of the cooling stage is as follows: and stopping heating when the temperature rises to 110 ℃, keeping the fixed temperature for 35min, then entering a cooling stage, and stopping heating to naturally cool the temperature of the fiber wound composite material.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010698684.2A CN111844804B (en) | 2020-07-20 | 2020-07-20 | Microwave curing process and device for fiber winding composite material |
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| CN202010698684.2A CN111844804B (en) | 2020-07-20 | 2020-07-20 | Microwave curing process and device for fiber winding composite material |
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| DE10251580B4 (en) * | 2002-03-08 | 2013-01-10 | Airbus Operations Gmbh | Method for producing a component made of fiber-reinforced plastic |
| CN101402256B (en) * | 2008-09-05 | 2012-08-15 | 中国船舶重工集团公司第七二五研究所 | Compression moulding forming method with wet-process for wave-suction composite material |
| CN103587128B (en) * | 2013-10-15 | 2015-10-07 | 南京航空航天大学 | The method and apparatus of the shaping high-performance composite material structural member of microwave-pressurized tank |
| CN106273536B (en) * | 2016-08-16 | 2018-11-23 | 中国商用飞机有限责任公司 | The microwave curing manufacturing process and its laminate of carbon fiber/epoxy resin composite material |
| CN109203510B (en) * | 2018-09-21 | 2020-07-14 | 江苏新扬新材料股份有限公司 | Preparation method of joint flange |
| CN209096062U (en) * | 2018-12-07 | 2019-07-12 | 中南大学 | A kind of automatic control of resin-based carbon fiber composite is heating and curing device |
| CN110696389B (en) * | 2019-11-20 | 2020-07-28 | 西安交通大学 | Fiber reinforced thermosetting composite material preformed body curing method |
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