CN106079481A - A kind of forming method of the composite with lightning protected effect - Google Patents
A kind of forming method of the composite with lightning protected effect Download PDFInfo
- Publication number
- CN106079481A CN106079481A CN201610517789.7A CN201610517789A CN106079481A CN 106079481 A CN106079481 A CN 106079481A CN 201610517789 A CN201610517789 A CN 201610517789A CN 106079481 A CN106079481 A CN 106079481A
- Authority
- CN
- China
- Prior art keywords
- composite
- resin
- forming method
- protected effect
- lightning protected
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- 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
- B29C70/40—Shaping or impregnating by compression not applied
- B29C70/42—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles
- B29C70/44—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding
- B29C70/443—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding and impregnating by vacuum or injection
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B7/00—Mixing; Kneading
- B29B7/002—Methods
-
- 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
-
- 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
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
- B29C41/12—Spreading-out the material on a substrate, e.g. on the surface of a liquid
Abstract
The invention discloses the forming method of a kind of composite with lightning protected effect.First the method will be dispersed with the resin molding paving of conductive nano granule on fiber weaving cloth preform, then by the Resin film infusion improved, conductive nano granule is made to form Gradient distribution along thickness of composite material direction, thus improve composite material conductive characteristic, reduce the lightning damage of composite.It is compared to tradition and uses the lightning protected mode of composite of metal surface modification; forming method of the present invention is simple; it is greatly saved the consumption of the energy; save manufacturing cost; it is effectively reduced the weight of composite element, it is to avoid corrosion that metallic protective material exists and the problem such as the strongest with composite caking property.
Description
Technical field
The present invention relates to the lightning protected field of composite, particularly to a kind of composite with lightning protected effect
Forming method.
Background technology
It is strong that fiber-reinforced resin matrix compound material has high ratio, high resistance to corrosion, and the programmable advantage of intensity is the most extensively applied
On vehicle construction material, to improve aircraft weight, mobility, reliability, it is also possible to when being greatly improved aircraft flight
Between, its consumption has become with application level weighs the important symbol that Flight Vehicle Structure is advanced.But, compare traditional metal material
Material, although the carbon fiber in composite has preferable electric conductivity, but insulative resin matrix has intercepted conductive path so that
Lightning current is difficult to derive at material surface generate substantial amounts of Joule heat, composite is carried out ablation, is substantially reduced its intensity
And rigidity, thus the safety and economy to aircaft configuration brings great challenge.
At present for the method for composite lightning strike protection, mainly by methods such as net paper tinsel cladding, surface sprayings by height
The metal material of conductivity is attached on composite structure surface.Lightning protection such as Boeing 787 technique for aircraft composite airframe structure
The measure of hitting is to add people's wire netting, by thunder-strike current carrying-off in composite fuselage manufacture process.But, highdensity metal material
Material not only increases the weight of composite structure, too increases the manufacturing cost of composite structure simultaneously；Further, metal material
Material easily corrodes, relatively low with resin bonding intensity so that and easily there is space in the surface between composite, when thunderbolt electricity
Stream can be through out-of-date generation electric arc and spark, and the fuel tank in structure that the most possibly even ignites causes aircraft to explode.Purport of the present invention
In the problem existed for current lightning Protection measure, new solution is proposed.
Summary of the invention
It is an object of the invention to overcome above-mentioned prior art not enough, it is provided that a kind of composite wood with lightning protected effect
The forming method of material.
The technology of the present invention solution is so to solve:
The present invention has the advantage that and beneficial effect, and the present invention is by the Resin film infusion improved so that nanometer
Conductive particle forms Gradient distribution along thickness of composite material direction, to improve composite material conductive characteristic, reduces composite
Lightning damage.Being compared to tradition and use the lightning protected mode of composite of metal surface modification, the present invention uses one
Change molding mode, simple, it is greatly saved the consumption of the energy, has saved manufacturing cost, be effectively reduced composite structure
The weight of part, it is to avoid the problems such as the corrosion that metal exists is the strongest with caking property.Moreover, the present invention can also pass through resin molding
Conductive nano granule content and infiltration process state modulator conductive nano granule are in the distribution of composite inner, thus realize
Composite material conductive characteristic is designed, meets the lightning strike protection demand of aircraft different parts.
Accompanying drawing explanation
A kind of composite with lightning protected effect of Fig. 1 and the shaping schematic view of forming method thereof
Detailed description of the invention
The present invention will be further described below in conjunction with the accompanying drawings.
1) preparation of conductive nano particulate resin film it is dispersed with.By conductive nano granule with the resin containing solvent at a high speed
Carry out under blender mixing and disperse 2-3 hour, then, film former is dissolved in the scattered conductive nano granule of previous step and
Resin compound, adds high temperature modification firming agent and mixes.Finally, obtained resin system is poured on 90-120 DEG C of iron plate,
Its flow casting molding is made to form the resin molding containing dispersion conductive nano granule.
2) fiber preform body-shaping.It is first according to die size cutting resin molding and fiber cloth, then will cut
Fiber cloth carries out paving along die surface, then by resin molding cover it, finally, uses sealant by preform four
Zhou Jinhang seals.
3) fiber preform is body formed.According to Resin film infusion, described preform is coated with microporous filter membrane,
Build vacuum diversion system on microporous filter membrane, and form die cavity with vacuum bag film sealed mold, the die cavity after sealing is taken out
Application of vacuum, heats mould simultaneously so that it is temperature reaches between 100-140 DEG C.When resin infiltration, due to sealant
Effect, the lay on fiber cloth surface has the resin molding of conductive nano granule can only carry out infiltration by through-thickness, and due to fibre
Wei Bu can intercept the flowing of conductive nano-particles, and therefore conductive particle will form concentration ladder along thickness of composite material direction
Degree.
4) composite solidification.Above-mentioned fiber preform body is put in vacuum drying oven, according to the solidification of resin types
Process conditions are heating and curing, and make surface and contain the composite product of conductive nano granule.
Described one or more nanometers that conductive nano granule is CNT, Graphene, nanometer silver, nano nickel etc.
Grain, described conductive nano particle surface can be through different modification mode with the dispersion requirement of satisfied reality.
The described resin containing solvent, for unsaturated polyester (UP), epoxy resin, bimaleimide resin, cyanate resin
Fat and the dicyandiamide solution of correspondence thereof, or mix and dicyandiamide solution for various kinds of resin.
Described fiber cloth is a kind of fiber or the fibers of multiple fibrage such as glass fibre, carbon fiber, aramid fiber
Cloth.
The effect of described sealant is to limit resin flow direction, makes resin carry out infiltration along thickness direction.Described close
The kind of envelope agent is the refractory seals agent such as rubber, politef.
The effect of described microporous filter membrane is to prevent nano conducting powders from discharging curing system with resin, described microporous filter membrane
Kind is the microporous filter membrane such as nylon, polypropylene, polyether sulfone.
In above-mentioned preparation method, need use Resin Film Infusion auxiliary material mainly include flow-guiding cloth, lead sebific duct with
And vacuum bag, these constitute described Resin Film Infusion system together.
When described evacuation processes, making the vacuum of described die cavity preferably reach more than 0.09MPa, mould heating-up temperature needs
Reaching between 110 DEG C-140 DEG C, the whole Resin Film Infusion time is preferably between 3-5h, and then insulation 7-12h is as resin
Precuring.
In above-mentioned preform forming process, the time of described precuring need to be special according to the solidification of resin system with temperature
Depending on property, this preferred precuring system can allow the first resin system suitably harden, and prevents resin system completion of cure simultaneously.
Its principle of the present invention is as it is shown in figure 1, by Resin film infusion, be coated with 2 containing conductive nano in 1 fiber cloth
The resin molding of granule, by heating 3 moulds, completes Resin film infusion, thus conductive nano granule is deposited on composite wood
Material surface, to improve composite material surface electrical conductivity, reduces the lightning damage of composite.
Embodiment 1
The present embodiment, as a example by preparing aircraft passenger compartment hatch door, uses multi-walled carbon nano-tubes to improve fibre reinforced cyanate multiple
The surface conductivity of condensation material, reduces the thunder and lightning infringement for aircraft passenger compartment hatch door.
Concrete grammar is,
1) preparation of multi-walled carbon nano-tubes resin molding it is dispersed with.By the multi-walled carbon nano-tubes modified through cetylamine of 0.5 part
Join in the dimethyl phthalate of 300 parts, carry out mixing under homogenizer and disperse 3 hours, being subsequently adding 100
The N, N'-(4,4'-methylenediphenyl) of part, after 30 minutes high-speed stirred 2 hours for ultrasonic disperse at normal temperatures.
Scattered multi-walled carbon nano-tubes and resin compound are stirred 12 hours at 180 DEG C, evaporative removal solvent.
Then, material temperature is increased to 135 DEG C, adds the 2 of 86 parts, 2 '-diallyl bisphenol, stirs 40 minutes, then adds at 100 DEG C
Enter the bisphenol A cyanate ester of 186 parts, stir to clarify.Material temperature is heated at 190 DEG C, adds the film former polyether sulfone of 5 parts,
Stirring makes it be dissolved in the middle of resin, stirs to clarify.The reinforcement mixed and resin system mixture are poured into 120 DEG C
Upper iron plate, cool to room temperature and make casting resin films molding.
2) carbon fibre preform sizing.The 300g/m that carbon cloth is selected2T300 unidirectional carbon is weaved cotton cloth.It is first according to
The size cutting resin molding of aircraft passenger compartment hatch door and carbon cloth, then the carbon cloth cut is carried out along die surface
Paving, then by resin molding cover it, finally, uses (5) sealant rubber preform surrounding to be sealed.
3) carbon fibre preform molding.According to Resin film infusion, described preform is coated with microporous filter membrane,
Microporous filter membrane builds vacuum diversion system, and forms closing die cavity with vacuum bag film sealed mold, to the die cavity after sealing
Carrying out evacuation process, vacuum reaches 0.09MPa, mould is heated to 120 DEG C simultaneously, the whole Resin Film Infusion time
For 3h, then insulation 8h carries out the precuring of resin.
4) composite solidification.Above-mentioned carbon fibre preform is put in vacuum drying oven, carries out 200 DEG C/5h+230
DEG C/cured of 3h, cool to room temperature with the furnace, it is thus achieved that the carbon fiber of multi-walled carbon nano-tubes through-thickness Gradient distribution is combined
Material aircraft passenger compartment hatch door, its sheet resistance can reach 4 × 102square-1。
Embodiment 2
The present embodiment, as a example by preparing unmanned plane wing, uses nanometer silver to improve glass fiber reinforced epoxy resin composite wood
The surface conductivity of material, reduces the thunder and lightning infringement for unmanned plane wing.
Concrete grammar is,
1) preparation of nanometer silver resin molding it is dispersed with.The nanometer silver of 1 part is joined in the acetone of 300 parts, high-speed stirred,
It is subsequently adding the novolac epoxy resin F-51 of 100 parts, at normal temperatures ultrasonic disperse 30 minutes, then carries out under homogenizer
Mixing and dispersion 2 hours 1 hour.It is little that scattered multi-walled carbon nano-tubes and epoxy resin composition are stirred 12 at 90 DEG C
Time, evaporative removal solvent.Then, material temperature being increased to 190 DEG C, add the film former polyether sulfone of 5 parts, stirring makes it be dissolved in tree
In the middle of fat, then cool to 120 DEG C, add the high temperature modification firming agent DADPS of 30 parts, stir to clarify.By mix
Reinforcement and resin system mixture are poured into the upper iron plate of 130 DEG C, cool to room temperature and make casting resin films molding.
2) glass fibre preform body-shaping.The 480g/m that glass fabric is selected2Non-twisting glass fibre is weaved cotton cloth.First press
According to size cutting resin molding and the glass fabric of unmanned plane wing, then by the glass fabric that cuts along die surface
Carry out paving, then by resin molding cover it, finally, use (5) sealant politef preform surrounding to be entered
Row seals.
3) glass fibre preform is body formed.According to Resin film infusion, described preform is coated with micropore filter
Film, builds vacuum diversion system on microporous filter membrane, and forms closing die cavity with vacuum bag film sealed mold, to the mould after sealing
Chamber carries out evacuation process, and vacuum reaches 0.095MPa, mould is heated to 130 DEG C, whole Resin Film Infusion simultaneously
Time is 4h, and then insulation 9h carries out the precuring of resin.
4) composite solidification.Above-mentioned carbon fibre preform is put in vacuum drying oven, carries out 180 DEG C/5h+200
DEG C/cured of 3h, cool to room temperature with the furnace, it is thus achieved that the glass fiber compound material of nanometer silver through-thickness Gradient distribution
Unmanned plane wing, its sheet resistance can reach 104square-1。
Claims (7)
1. the forming method of a composite with lightning protected effect, it is characterised in that step is as follows:
1) preparation of conductive nano particulate resin film it is dispersed with；By conductive nano granule with the resin containing solvent in high-speed stirred
Carry out under machine mixing and disperse 2-3 hour, then film former is dissolved in scattered conductive nano granule and resin compound,
Add high temperature modification firming agent to mix；Obtained resin system is poured on the iron plate that temperature is 90-120 DEG C again so that it is stream
Prolong molding and form the resin molding containing dispersion conductive nano granule；
2) fiber preform body-shaping；It is first according to die size cutting resin molding and fiber cloth, the fibre that then will cut
Wei Bu carries out paving along die surface, then by resin molding cover it, uses sealant to carry out close by preform surrounding
Envelope；
3) fiber preform is body formed；According to Resin film infusion, above-mentioned preform is coated with microporous filter membrane, at micropore
Build vacuum diversion system on filter membrane, and form die cavity with vacuum bag film sealed mold, the die cavity after sealing is carried out evacuation
Process, mould is heated so that it is temperature reaches between 100-140 DEG C simultaneously；
4) composite solidification；Above-mentioned fiber preform body is put in vacuum drying oven, according to the curing process of resin types
Condition is heating and curing, and makes surface and contains the composite product of conductive nano granule.
The forming method of a kind of composite with lightning protected effect the most according to claim 1, it is characterised in that:
Described conductive nano granule is one or more nano-particle of CNT, Graphene, nanometer silver, nano nickel.
The forming method of a kind of composite with lightning protected effect the most according to claim 1, it is characterised in that:
The described resin containing solvent, for unsaturated polyester (UP), epoxy resin, bimaleimide resin, cyanate ester resin and right
The dicyandiamide solution answered, or mix and dicyandiamide solution for various kinds of resin.
The forming method of a kind of composite with lightning protected effect the most according to claim 1, it is characterised in that:
Described high temperature modification firming agent be aromatic polyamine, anhydride, resol, dicyandiamide one or more.
The forming method of a kind of composite with lightning protected effect the most according to claim 1, it is characterised in that:
Described fiber cloth is glass fibre, carbon fiber, a kind of fiber of aramid fiber or the fiber cloth of multiple fibrage.
The forming method of a kind of composite with lightning protected effect the most according to claim 1, described sealant
Kind be rubber, politef refractory seals agent.
The forming method of a kind of composite with lightning protected effect the most according to claim 1, described micropore is filtered
The kind of film is nylon, polypropylene or polyethersulfone millipore filter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201610517789.7A CN106079481B (en) | 2016-07-04 | 2016-07-04 | Forming method of composite material with lightning protection effect |
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|---|---|---|---|
| CN201610517789.7A CN106079481B (en) | 2016-07-04 | 2016-07-04 | Forming method of composite material with lightning protection effect |
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| CN106079481A true CN106079481A (en) | 2016-11-09 |
| CN106079481B CN106079481B (en) | 2020-11-10 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109808201A (en) * | 2019-01-22 | 2019-05-28 | 西安交通大学 | Forming method is prepared with the fibre-reinforced wearing composite material of nanometer gradient |
| CN111716835A (en) * | 2020-06-19 | 2020-09-29 | 哈尔滨工业大学 | Lightning protection composite material and preparation method thereof |
| CN115431605A (en) * | 2022-07-25 | 2022-12-06 | 成都飞机工业（集团）有限责任公司 | X-band stealth/lightning protection skin and preparation method thereof |
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Cited By (3)
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|---|---|---|---|---|
| CN109808201A (en) * | 2019-01-22 | 2019-05-28 | 西安交通大学 | Forming method is prepared with the fibre-reinforced wearing composite material of nanometer gradient |
| CN111716835A (en) * | 2020-06-19 | 2020-09-29 | 哈尔滨工业大学 | Lightning protection composite material and preparation method thereof |
| CN115431605A (en) * | 2022-07-25 | 2022-12-06 | 成都飞机工业（集团）有限责任公司 | X-band stealth/lightning protection skin and preparation method thereof |
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| CN106079481B (en) | 2020-11-10 |
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