CN108426760A - The method for preparing carbon fibre composite interlaminar shear strength batten - Google Patents
The method for preparing carbon fibre composite interlaminar shear strength batten Download PDFInfo
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- CN108426760A CN108426760A CN201810285501.7A CN201810285501A CN108426760A CN 108426760 A CN108426760 A CN 108426760A CN 201810285501 A CN201810285501 A CN 201810285501A CN 108426760 A CN108426760 A CN 108426760A
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- fiber
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/36—Embedding or analogous mounting of samples
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/24—Investigating strength properties of solid materials by application of mechanical stress by applying steady shearing forces
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/36—Embedding or analogous mounting of samples
- G01N2001/366—Moulds; Demoulding
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Abstract
Composite material interlayer shear strength spline method is prepared the present invention relates to a kind of, belongs to the testing field of composite material.A) before sample preparation, according to the radical of carbon fiber needed for the content calculation of fiber in the specification of carbon fiber and composite material batten；B) it weighs and prepares suitable epoxy resin adhesive liquid, put it into and be hot melt to transparence in baking oven；C) carbon fiber is placed on uncoil-stand, is conducted into steeping vat, the epoxy resin adhesive liquid after hot melt is poured into steeping vat, do not had fiber, and wind the fiber after corresponding radical dipping glue on twining filament plate；D) fiber for twining and impregnating glue on filament plate is removed with blade, it is straight to be put into the groove for the mold groove body for preheating and being evenly coated with releasing agent in an oven in advance after symmetrical fold 3 times；E) fiber and groove body are put into together in 140 DEG C of baking oven and heat 60min, mold groove body is taken out when glue is hardened, it puts back in 140 DEG C of baking ovens and continues to heat 60 90min, 150 280Nm of repressurization after taking-up, it places into 160 DEG C of baking ovens after curing 2 4h, cooling, demoulding cuts into required size measuring batten.
Description
Technical field
The present invention relates to composite material test field, specifically a kind of to prepare carbon fibre composite interlayer shear strong
Spend the method for batten.
Background technology
Carbon fiber is the new carbon that 90% or more is up to through phosphorus content made from 1300-1600 DEG C of high temperature carbonization, tool
There are the superiority such as high specific strength, high ratio modulus, high temperature resistant, corrosion-resistant, endurance, radioresistance, conduction, heat transfer, damping, noise reduction
Can, it is widely used in the high-tech areas such as Aeronautics and Astronautics, is important strategic materials.As a kind of fragile material, carbon fiber
It is seldom used alone, is mostly combined with epoxy resin and composite material is made to give full play to its excellent performance, due to fibre reinforced
The mechanical property of polymer matrix composites depends on resin matrix and enhances the adhesive property at carbon fiber interface, therefore, commonly uses carbon
The height of fiber interlaminar shear strength weighs the quality of adhesive property, currently, it is logical to prepare carbon fiber interlaminar shear strength batten
Frequently with flow be：One is debatching is carried out to carbon fibre tow using uncoil-stand, glue groove then is imported through godet,
It winds to form unidirectional prepreg cloth through winding roller, another kind is to carry out uniform coating to resin through applying membrane process, then through impregnation work
Unidirectional pre-immersion material is made in sequence, and using shearing, lamination, vacuum pressing-combining, tablet is made in drying and machining operation cuts into symbol
Desired batten, both method of preparing sample not only complex process, long flow path are closed, but also sample making apparatus takes up space greatly, it is unsuitable
Sample preparation can not be completed using one to operate, in addition, the carbon fiber cylinder number needed in sample making course is more, will also result in not in laboratory
Necessary waste.
Invention content
For overcome the deficiencies in the prior art, present invention offer is a kind of preparing carbon fibre composite interlaminar shear strength sample
The method of item, can fiber surface in effective monitoring carbon fibre composite production process by the experiment of the interlaminar shear strength of batten
Adhesive property and effect, provide experimental data for the raising improvement of carbon fibre composite product quality, this method have with
Lower advantage:Sample preparation is quick, easy to operate, equipment takes up space it is small be suitble to one in laboratory independent operation, cost-effective carbon fiber
It is low to tie up material consumption.
In order to solve the above-mentioned technical problem the present invention, provides a kind of method preparing carbon fiber interlaminar shear strength batten,
Include the following steps：
A) before sample preparation, according to the root of carbon fiber needed for the content calculation of fiber in the specification of carbon fiber and composite material batten
Number：Assuming that volume fraction shared by carbon fiber is f in batten, interlayer shear batten width is b mm, and the thickness of sample preparation is h mm, often
The density of root carbon fibre tow is Dg/cm3, the line density of carbon fibre tow is dg/km, then required carbon fiber radical N should meet
Formula：N=1000fbh /(d/D)；
B) it weighs and prepares suitable epoxy resin adhesive liquid, put it into and be hot melt to transparence in baking oven；
C) carbon fiber is placed on uncoil-stand, the reeling-off tension for applying 5-15N is conducted into steeping vat, by the epoxy after hot melt
Resin adhesive liquid is poured into steeping vat, does not have fiber, and the fiber after corresponding radical dipping glue is wound on twining filament plate；
D) it removes the fiber for twining and impregnating glue on filament plate with blade, after symmetrical fold 3 times, applies certain at fiber both ends
Power, it is straight to be put into the groove for the mold groove body for preheating and being evenly coated with releasing agent in an oven in advance；
E) fiber and groove body are put into together in 140 DEG C of baking oven and heat 60min, mold groove body is taken out when glue is hardened, by slot
Body and upper cover are forced between groove body and upper cover after agreeing with there are when the gap of about 0.5-0.8mm, are put back in 140 DEG C of baking ovens and are continued
60-90min, repressurization 150-280Nm after taking-up are heated, is placed into 160 DEG C of baking ovens after curing 2-4h, cooling, demoulding
Cut into required size measuring batten.
The advantageous effect that the present invention has is can effective monitoring carbon fiber composite by the interlaminar shear strength experiment of batten
Expect that the adhesive property and effect of fiber surface in production process, the improvement for the product quality of carbon fibre composite provide experiment
The advantages of data, the invention is:Sample preparation is quick, easy to operate, equipment takes up space it is small be suitble to one independently grasped in laboratory
Make, cost-effective carbon fibre material consumption is low.
Embodiment one：
The line density of fiber used in the present embodiment is 445g/km, fibre density 1.78g/cm3, carbon fiber interlayer shear
The method for making sample of strength test is as follows：
1. calculating：Assuming that shared volume fraction is 60% to carbon fiber in the sample, then needed for carbon fiber interlaminar shear strength batten
Number of fiber be：n=60%×10×2×103/（445/1.78）=48, be 48/2=24 circle around the number of turns of fiber is taken.
2. mold preheats：Uniform smearing release agent is distinguished in the groove body of mold and on the boss of upper cover, is put into 140 DEG C of baking oven
In preheated.
It is 5N, the tree of control fiber by adjusting reeling-off tension 3. impregnating glue to carbon fibre tow using gumming device
Fat content, it is ensured that the adequacy of dipping.
4. by certain tension is applied to it after the carbon fibre tow doubling 3 times for being impregnated with epoxy resin, ensure that it is in
Straight configuration is then placed in mold slots body, and groove body both sides are stretched out at the both ends of carbon fibre tow, by mold together with the fibre after folding
Dimension is put into 140 DEG C of baking oven and heats 60min together, and after taking-up, the boss of upper cover and groove body are agreed with, be forced into mold there are
It is put back to behind the gap of 0.5mm in 140 DEG C of baking ovens and continues to heat 60min, clamping device is applied with torque spanner after taking-up
The power of 280Nm so that the volume of carbon fibre tow accounts for mold volumes 60%, and the volume of epoxy resin accounts for mold volumes at this time
40%。
5. the mold of secondary pressurized is put into baking oven, sample is made to cure 2h at 160 DEG C.
After 6. the mold in taking-up baking oven is cooled to room temperature, the batten in mold is taken out, 10 length 20mm are cut into,
Width is 6mm, is highly the test bars of 2mm.
Entire sample preparation process needs operative employee 1, used time 5-6 hour.
Embodiment two：
The line density of fiber used in the present embodiment is 198g/km, fibre density 1.78g/cm3, cut between carbon fiber layer
The method for making sample of shearing stress test is as follows：
1. calculating：Assuming that shared volume fraction is 50% to carbon fiber in the sample, then carbon fiber interlaminar shear strength batten institute
Need number of fiber be：n=50%×10×2×103/（198/1.78）=90, be 90/2=45 circle around the number of turns of fiber is taken.
2. mold preheats：Uniform smearing release agent is distinguished in the groove body of mold and on the boss of upper cover, is put into 140 DEG C
It is preheated in baking oven.
It is 10N, the tree of control fiber by adjusting reeling-off tension 3. impregnating glue to carbon fibre tow using gumming device
Fat content, it is ensured that the adequacy of dipping.
4. by certain tension is applied to it after the carbon fibre tow doubling 3 times for being impregnated with epoxy resin, ensure that it is in
Straight configuration is then placed in mold slots body, and mold groove body both sides are stretched out at the both ends of carbon fibre tow, by mold together with folding after
Fiber be put into together in 140 DEG C of baking oven heat 60min take out after, mold upper cover boss and groove body are agreed with, mould is forced into
Tool applies clamping device with torque spanner after taking-up there are putting back in 140 DEG C of baking ovens to continue to heat 75min behind the gap of 0.65mm
Add the power of 215Nm so that the volume of carbon fibre tow accounts for mold volumes 50%, and the volume of epoxy resin accounts for mold volumes at this time
50%.
5. the mold of secondary pressurized is put into baking oven, sample is made to cure 3h at 160 DEG C.
After 6. the mold in taking-up baking oven is cooled to room temperature, the batten in mold is taken out, 10 length 20mm are cut into,
Width is 6mm, is highly the test bars of 2mm.
Entire sample preparation process needs operative employee 1, about 7-8 hours used time.
Embodiment three：
The line density of fiber used in the present embodiment is 800g/km, fibre density 1.80g/cm3, cut between carbon fiber layer
The method for making sample of shearing stress test is as follows：
1. calculating：Assuming that shared volume fraction is 40% to carbon fiber in the sample, then needed for carbon fiber interlaminar shear strength batten
Number of fiber be：n=40%×10×2×103/（800/1.80）=18, be 18/2=9 circle around the number of turns of fiber is taken.
2. mold preheats：The even smearing demoulding of uniform smearing release agent respectively in the groove body of mold and on the boss of upper cover
Agent is put into 140 DEG C of baking oven and is preheated.
It is 10N, the tree of control fiber by adjusting reeling-off tension 3. impregnating glue to carbon fibre tow using gumming device
Fat content, it is ensured that the adequacy of dipping.
4. by certain tension is applied to it after the carbon fibre tow doubling 3 times for being impregnated with epoxy resin, ensure that it is in
Straight configuration is then placed in the groove body of mold, and groove body both sides are stretched out at the both ends of carbon fibre tow, by mold together with folding after
Fiber is put into 140 DEG C of baking oven together after heating 60min taking-ups, and the boss of mold upper cover and groove body are agreed with, mould is forced into
Tool applies clamping device with torque spanner after taking-up there are putting back in 140 DEG C of baking ovens to continue to heat 90min behind the gap of 0.8mm
Add the power of 150Nm so that the volume of carbon fibre tow accounts for mold volumes 40%, and the volume of epoxy resin accounts for mold volumes at this time
60%.
5. the mold of secondary pressurized is put into baking oven, sample is made to cure 4h at 160 DEG C.
After 6. the mold in taking-up baking oven is cooled to room temperature, the batten in mold is taken out, 10 length are cut into
20mm, width 6mm are highly the test bars of 2mm.
Entire sample preparation process needs operative employee 1, about 8-9 hours used time.
Carbon fibre tow length is more than the length of mold, and the gap of mold is run through the both ends of the surface in die length direction, will be soaked
The tow both ends of stain glue are put into mold after stretching, mold both sides are stretched out at tow both ends, are ensured in pressure process, can be to filament
Beam both ends apply tension, and when both having ensured that fibre bundle did not wind or crimps in mold, while also can avoid pressurization, tow occurs
Rebound phenomenon causes pressurized portion to crimp, and mold should be evenly coated with releasing agent before use, is put into preheating in baking oven, is convenient for sample
It is demoulded after item molding, the article that the material is soft need to be used to beat mold when demoulding, prevent damage batten.
When carrying out secondary pressurized to mold, applied to agreeing with rear mold by the bolt of clamping device using torque spanner
The pressure of 150-280Nm had both ensured consistency and repeatability prepared by batten, ensured that the fiber content in batten is full
Foot requires content.
Claims (1)
1. a kind of method preparing composite material interlayer shear strength batten, which is characterized in that include the following steps：
A) before sample preparation, according to the root of carbon fiber needed for the content calculation of fiber in the specification of carbon fiber and composite material batten
Number：Assuming that volume fraction shared by carbon fiber is f in batten, interlayer shear batten width is b mm, and the thickness of sample preparation is h mm, often
The density of root carbon fibre tow is Dg/cm3, the line density of carbon fibre tow is dg/km, then required carbon fiber radical N should meet
Formula：N=1000fbh /(d/D)；
B) it weighs and prepares suitable epoxy resin adhesive liquid, put it into and be hot melt to transparence in baking oven；
C) carbon fiber is placed on uncoil-stand, the reeling-off tension for applying 5-15N is conducted into steeping vat, by the epoxy after hot melt
Resin adhesive liquid is poured into steeping vat, does not have fiber, and the fiber after corresponding radical dipping glue is wound on twining filament plate；
D) it removes the fiber for twining and impregnating glue on filament plate with blade, after symmetrical fold 3 times, applies certain at fiber both ends
Power, it is straight to be put into the groove for the mold groove body for preheating and being evenly coated with releasing agent in an oven in advance；
E) fiber and groove body are put into together in 140 DEG C of baking oven and heat 60min, mold groove body is taken out when glue is hardened, by slot
Body and upper cover are forced between groove body and upper cover after agreeing with there are when the gap of about 0.5-0.8mm, are put back in 140 DEG C of baking ovens and are continued
60-90min, repressurization 150-280Nm after taking-up are heated, is placed into 160 DEG C of baking ovens after curing 2-4h, cooling, demoulding
Cut into required size measuring batten.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201810285501.7A CN108426760A (en) | 2018-04-03 | 2018-04-03 | The method for preparing carbon fibre composite interlaminar shear strength batten |
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| CN201810285501.7A CN108426760A (en) | 2018-04-03 | 2018-04-03 | The method for preparing carbon fibre composite interlaminar shear strength batten |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110487643A (en) * | 2019-07-26 | 2019-11-22 | 南京航空航天大学 | A kind of micron order fiber cutting strength test method |
| CN110553930A (en) * | 2019-09-17 | 2019-12-10 | 大连航天高科科技有限公司 | Improved test device and test method for shear performance of composite material base/fiber interface |
| CN111044426A (en) * | 2018-10-15 | 2020-04-21 | 中国商用飞机有限责任公司 | Manufacturing method of porosity contrast test block and porosity contrast test block |
| CN112730064A (en) * | 2020-12-29 | 2021-04-30 | 连云港神鹰复合材料科技有限公司 | Method for testing tensile breaking strength of carbon fiber fabric |
| CN112848383A (en) * | 2020-12-31 | 2021-05-28 | 荣成碳纤维科技有限公司 | Preparation method and preparation device of carbon fiber interlaminar shear sample strip |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111044426A (en) * | 2018-10-15 | 2020-04-21 | 中国商用飞机有限责任公司 | Manufacturing method of porosity contrast test block and porosity contrast test block |
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| CN110487643A (en) * | 2019-07-26 | 2019-11-22 | 南京航空航天大学 | A kind of micron order fiber cutting strength test method |
| CN110553930A (en) * | 2019-09-17 | 2019-12-10 | 大连航天高科科技有限公司 | Improved test device and test method for shear performance of composite material base/fiber interface |
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| CN112730064A (en) * | 2020-12-29 | 2021-04-30 | 连云港神鹰复合材料科技有限公司 | Method for testing tensile breaking strength of carbon fiber fabric |
| CN112848383A (en) * | 2020-12-31 | 2021-05-28 | 荣成碳纤维科技有限公司 | Preparation method and preparation device of carbon fiber interlaminar shear sample strip |
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