CN111310346A - Method for judging failure mode of carbon nano tube in composite material by considering size parameters - Google Patents
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Abstract
The invention discloses a method for judging a failure mode of a carbon nano tube in a composite material by considering a size parameter. The method takes three dimensional variables of the pipe diameter, the length and the inner-outer diameter ratio of the carbon nano tube as fixed values respectively, substitutes the basic mechanical properties of the carbon nano tube and the composite material into a formula, draws a coordinate graph to obtain a critical dimension curve of the other two variables, substitutes the specific dimensional parameters of the carbon nano tube into the coordinate graph during judgment, and judges the damage mode of the carbon nano tube in the composite material according to the relative position relationship of the dimensional parameters of the carbon nano tube and the critical dimension curve, so that the method can be used for guiding experiments and engineering practices.
Description
Technical Field
The invention relates to the field of composite materials, in particular to a method for judging a failure mode of a carbon nano tube in a composite material by considering a size parameter.
Background
Carbon Nanotubes (CNTs) are an ideal reinforcing material and have recently received a wide range of attention and applications in the field of composite materials. In fiber reinforced composites, the failure mode of carbon nanotubes is mainly pull-out and snap-off as a reinforcing and toughening material. The fibers at the crack are anchored in the matrix at the two sides of the crack to play a bridging role and prevent the crack from expanding. The adhesion and friction between the fiber and the matrix resist the pull-out force of the carbon nanotube. Along with the increase of the external load, the crack further expands, the drawing force borne by the fiber also increases, and when the drawing force is larger than the bonding force, the fiber is debonded from the matrix and begins to be drawn out. On the other hand, in the process that the fibers are pulled, if the tensile bearing capacity of the fibers is smaller than the bonding anchoring capacity, the pulling-out capacity is larger than the tensile bearing capacity of the fibers along with the increase of the pulling-out capacity, the fibers are pulled apart, and at the moment, the two ends of the fibers are still anchored in the matrix. The failure process is as follows: the fibers at the cleft are first slightly stretched, then pulled apart and finally pulled out of the cleft.
It can be seen that when the damage mode of the carbon nano tube is pull-out damage, the carbon nano tube and the matrix generate relative displacement, so that the deformability of the matrix can be increased, the energy of external load can be consumed by the friction force acting, and the toughness of the matrix can be increased; compared with pull-out failure, the pull-out failure is more sudden, and the fibers and the matrix hardly have relative displacement, so that the deformability of the matrix cannot be effectively improved. In recent years, carbon nanotubes have been developed to be longer and thinner in order to improve the performance of materials. The tube diameter and the length of the carbon nano tube are respectively key factors for determining the tensile bearing capacity and the anchoring force of the carbon nano tube, and the damage mode of the carbon nano tube in a matrix is directly influenced. With the increasing range of applications of carbon nanotubes in composite materials, the relationship between the failure mode of carbon nanotubes in composite materials and their dimensional characteristics should be proposed.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for judging the failure mode of a carbon nano tube in a composite material by considering a size parameter. The specific technical scheme is as follows:
considering the carbon nanotube hollow, an inner-outer diameter ratio λ D/D (D and D are the outer diameter and the inner diameter of the carbon tube, respectively) is defined: the single carbon nanotube can be simplified into a hollow cylindrical tube, and is anchored in a cement matrix, and the model schematic diagram of the carbon nanotube in the tension process is shown in figure 1. The frictional resistance F between the carbon tube and the substrate during the process of pulling out the carbon tubefComprises the following steps:
Ff＝πDxτi(1)
the tensile bearing capacity T of the carbon tube is as follows:
wherein: x is the anchoring length of the carbon tube in the matrix;
τithe friction force between the carbon tube and the matrix;
σ is the tensile strength of the carbon tube itself.
Experiments prove that the large carbon nanotubes are bent in the matrix, and the bending model of the carbon nanotubes in the matrix is shown in figure 2 (a). Taking the carbon nano tube at the outlet of the matrix for stress analysis, and when the angle between the carbon nano tube and the crack surface of the matrix is theta, as shown in figure 2(b), decomposing the extraction force F, wherein the method comprises the following steps:
Ff＝F sinθ (3)
when the pulling force F reaches F firstfSin theta, the carbon tube is pulled out, and when F reaches the tensile bearing capacity T of the carbon tube, the carbon tube is broken.
It should be noted here that because of the random disorientation distribution of the carbon nanotubes, the value of θ is randomly distributed between 0 ° and 90 °, and for macroscopically predicting the overall damage law of a certain type of carbon nanotubes, θ is taken as 45 °,
if the damage condition of a certain carbon nano tube needs to be specially considered, a specific theta can be obtained according to the observation of an electron microscope.
Further, to compare the relationship between the frictional resistance and the tensile load capacity of the carbon tube, the ratio of the two is defined:
wherein κ ═ τiAnd/sigma is the ratio of the friction resistance to the tensile strength of the carbon nanotube.
When gamma is less than 1, the carbon tube is pulled out, and along with the pulling out of the carbon tube, the anchoring length x is gradually reduced, the frictional resistance F is also reduced, and gamma is continuously reduced; when gamma is more than 1, the carbon tube is directly broken.
Further, consider the relationship of the carbon nanotube length L to the failure mode. The anchoring length x of the carbon tube in the matrix in the formula (4) varies between (0, L/2) with the crack distribution (it should be noted that when x > L/2, the other end of the anchor, x' < L/2, considers the end more prone to failure). And taking the average value x as L/4.
In summary, the critical dimensions of the carbon nanotube pull-out/snap failure are:
predicting the destruction mode of the carbon nanotube using equation (6):
the formula has three parameters related to the geometric dimension of the carbon nano tube, namely an outer diameter D, an inner-outer diameter ratio lambda and a length L. When the inner-outer diameter ratio lambda of the carbon nano tube is a set value, a critical relation line with the length L as an abscissa and the outer diameter D as an ordinate is obtained through the calculation of the formula (5), when the corresponding point of the length L and the outer diameter D of the carbon nano tube with the corresponding inner-outer diameter ratio lambda falls below the critical relation line, the carbon nano tube is broken in a breaking mode, and when the corresponding point falls above the critical relation line, the carbon nano tube is pulled out in a breaking mode. When the outer diameter D of the carbon nano tube is a set value, a critical relation line with the inner diameter ratio lambda as an abscissa and the length L as an ordinate is obtained through calculation of the formula (5), when the corresponding point of the length L of the carbon nano tube with the corresponding outer diameter D and the inner diameter ratio lambda falls below the critical relation line, the carbon nano tube is pulled out in the destruction mode, and when the corresponding point falls above the critical relation line, the carbon nano tube is pulled off in the destruction mode. When the length L of the carbon nano tube is a set value, a critical relation line with the inner-outer diameter ratio lambda as an abscissa and the outer diameter D as an ordinate is obtained through calculation of the formula (5), when the corresponding point of the outer diameter D and the inner-outer diameter ratio lambda of the carbon nano tube with the corresponding length L falls below the critical relation line, the carbon nano tube is broken in a breaking mode, and when the corresponding point falls above the critical relation line, the carbon nano tube is pulled out in the breaking mode.
For example, take σ to 50GPa, τi20MPa, then k is 0.4 × 10-3The graph shows the relationship between the failure mode of the carbon nanotube and three geometric parameters (such as fig. 3, fig. 4 and fig. 5). And substituting the geometric parameters of the carbon nano tube into the graph to obtain corresponding points, and judging the failure mode of the carbon nano tube according to the positions of the points.
The invention provides a method for judging the damage mode of a carbon nano tube in a composite material by analyzing the material characteristics of the carbon nano tube, and researchers can substitute the basic performance parameters of the carbon nano tube and a matrix into the method, thereby definitely judging the damage mode of the carbon nano tube in the composite material, effectively prejudging the damage of the composite material and guiding experiments and engineering practices.
Drawings
FIG. 1 is a schematic view of a hollow tube/fiber being pulled from a matrix;
FIG. 2(a) is a model of the bending of carbon nanotubes in a matrix;
FIG. 2(b) is a force analysis diagram of the carbon nanotube at the outlet of the substrate;
FIG. 3 is a graph showing the relationship between the critical diameter D and the critical length L when the carbon nanotube undergoes pull-out/snap-off failure transition;
FIG. 4 is a relationship between the critical length L and the critical inner-outer diameter ratio λ when the carbon nanotube undergoes pull-out/snap failure transition;
FIG. 5 is a relationship between the critical outer diameter D and the critical inner and outer diameter ratio λ when the carbon nanotube is pulled out/pulled out to break;
FIGS. 6(a) and 6(b) are a judgment drawing and a microscopic observation drawing, respectively, showing the breakage of the carbon nanotubes in example one;
FIGS. 7(a) and 7(b) are a judgment view and a microscopic observation picture, respectively, of the occurrence of breakage of carbon nanotubes in example two;
FIG. 8(a) and FIG. 8(b) are a judgment picture showing the occurrence of breakage of carbon nanotubes and a microscope observation picture, respectively, in the third example.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. The conditions not specified for the implementation are generally those in routine experiments.
Carbon nanotube reinforced cement-based composites are contemplated. Examples experiments will be performed with different kinds of multi-walled carbon nanotubes. Dispersing the multi-wall carbon nano-tube in aqueous solution, and then mixing the cement-based material with the aqueous solution of the carbon nano-tube. And after stirring uniformly, molding and maintaining for 28 days, knocking the tested test block through a compression and bending resistance test, and observing the damage condition of the carbon nano tube at the damage surface.
The first embodiment is as follows: failure mode prediction of a multi-walled carbon nanotube.
The parameters of the multi-wall carbon nano tube are as follows: d25 nm, D20 nm, length L30 μm, σ 50GPa, τiWhen 20MPa, λ is 0.8, and κ is 0.4 × 10-3。
The relationship between the damage mode and the geometric parameters of the carbon nanotubes is plotted by substituting λ 0.8 into formula (5) and calculating different corresponding critical values of the length L using formula (5) by changing the diameter D, as shown in fig. 6 (a).
The point (30,25) corresponding to the carbon nanotube is substituted into fig. 6(a), and it is found that the point is below the relationship line, and it is predicted that the carbon nanotube is broken. The carbon nanotube was observed with an electron microscope for verification, as shown in fig. 6(b), and the damage trace at the cut of the carbon nanotube was found to be obvious, which indicates that the carbon nanotube was actually snapped.
Example two: failure mode prediction of a multi-walled carbon nanotube.
The parameters of the multi-wall carbon nano tube are as follows: d30 nm, D20 nm, length L60 μm, σ 50GPa, τiWhen 20MPa, λ is 0.67, and κ is 0.4 × 10-3。
The relationship between the damage mode and the geometric parameter of the carbon nanotube is plotted by substituting 30nm for D in formula (5) and calculating different corresponding critical values of the length L using formula (5) by changing the inner-outer diameter ratio λ, as shown in fig. 7 (a).
The point (0.67,60) corresponding to the carbon nanotube was substituted into fig. 7(a), and it was found that the point was above the relationship line, and it was predicted that the carbon nanotube was broken. The carbon nanotube was observed by an electron microscope for verification, as shown in fig. 7(b), and the damage trace at the cut of the carbon nanotube was found to be obvious, which indicates that the carbon nanotube was actually snapped.
Example three: failure mode prediction of a multi-walled carbon nanotube.
The parameters of the multi-wall carbon nano tube are as follows: d50 nm, D15 nm, length L30 μm, σ 50GPa, τiWhen 20MPa, λ is 0.3, and κ is 0.4 × 10-3。
The relationship between the damage pattern of the carbon nanotube and the geometric parameter is plotted by substituting 30 μm for formula (5), changing the diameter D, and calculating the different corresponding critical values of the inner and outer diameter ratios λ using formula (5), as shown in fig. 8 (a).
The points (0.3,50) corresponding to the carbon nanotubes were substituted into FIG. 8(a) to determine the points, and it was found that the points were located above the relationship line, and it was predicted that the carbon nanotubes were pulled out and damaged. The carbon nanotube is observed by an electron microscope for verification, as shown in fig. 8(b), the end part of the carbon nanotube is complete and smooth, and no fracture trace is found, which indicates that the carbon nanotube is pulled out, and the judgment method provided by the invention is accurate.
The present invention is described in detail, and the embodiments are only preferred embodiments of the present invention to help understanding the method and the core idea of the present invention, so as to enable those skilled in the art to understand the contents of the present invention and to implement the same, and not to limit the protection scope of the present invention. Any modification, equivalent change or improvement made according to the spirit of the present invention should be covered within the protection scope of the present invention.
Claims (1)
1. The method for judging the damage mode of the carbon nano tube in the composite material by considering the size parameter is characterized in that the method is used as a critical size calculation formula for the carbon nano tube damage mode conversion according to the following formula,
wherein D is*λ is the ratio of the inner diameter to the outer diameter of the carbon nanotube, L is the length of the carbon nanotube, and κ ═ τi/σ，τiIs the friction between the carbon nanotube and the matrix, and σ is the tensile strength of the carbon nanotube itself.
Taking the inner-outer diameter ratio lambda of the carbon nano tube as a set value, obtaining a critical relation line with the length L as an abscissa and the outer diameter D as an ordinate by calculation of a formula (5), wherein when the corresponding point of the length L and the outer diameter D of the carbon nano tube with the corresponding inner-outer diameter ratio lambda falls below the critical relation line, the damage mode of the carbon nano tube is snapping, and when the corresponding point falls above the critical relation line, the damage mode of the carbon nano tube is pulling out; or:
when the outer diameter D of the carbon nano tube is taken as a set value, a critical relation line with the inner diameter ratio lambda as a horizontal coordinate and the length L as a vertical coordinate is obtained through calculation of a formula (5), when the corresponding point of the length L of the carbon nano tube with the corresponding outer diameter D and the inner diameter ratio lambda falls below the critical relation line, the carbon nano tube is pulled out in a destruction mode, and when the corresponding point falls above the critical relation line, the carbon nano tube is pulled off in the destruction mode; or:
and (3) taking the length L of the carbon nanotube as a set value, obtaining a critical relation line with the inner-outer diameter ratio lambda as an abscissa and the outer diameter D as an ordinate by calculation of the formula (5), wherein when the corresponding point of the outer diameter D and the inner-outer diameter ratio lambda of the carbon nanotube with the corresponding length L falls below the critical relation line, the damage mode of the carbon nanotube is snapping, and when the corresponding point falls above the critical relation line, the damage mode of the carbon nanotube is pulling out.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101272851A (en) * | 2005-02-28 | 2008-09-24 | 霍尼韦尔国际公司 | Stationary phase for a micro fluid analyzer |
| CN102113089A (en) * | 2008-03-05 | 2011-06-29 | 伊利诺伊大学评议会 | Stretchable and foldable electronic devices |
| WO2014150890A1 (en) * | 2013-03-15 | 2014-09-25 | Hyperion Catalysis International, Inc. | Methods of making nanofiber electrodes for batteries |
| CN105723250A (en) * | 2013-09-13 | 2016-06-29 | 康宁股份有限公司 | Low-color scratch-resistant articles with a multilayer optical film |
| CN106198640A (en) * | 2016-06-27 | 2016-12-07 | 北京航空航天大学 | A kind of woven electric resistance sensor for composite and processing method thereof |
-
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- 2020-02-24 CN CN202010113645.1A patent/CN111310346B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101272851A (en) * | 2005-02-28 | 2008-09-24 | 霍尼韦尔国际公司 | Stationary phase for a micro fluid analyzer |
| CN102113089A (en) * | 2008-03-05 | 2011-06-29 | 伊利诺伊大学评议会 | Stretchable and foldable electronic devices |
| WO2014150890A1 (en) * | 2013-03-15 | 2014-09-25 | Hyperion Catalysis International, Inc. | Methods of making nanofiber electrodes for batteries |
| CN105723250A (en) * | 2013-09-13 | 2016-06-29 | 康宁股份有限公司 | Low-color scratch-resistant articles with a multilayer optical film |
| CN106198640A (en) * | 2016-06-27 | 2016-12-07 | 北京航空航天大学 | A kind of woven electric resistance sensor for composite and processing method thereof |
Non-Patent Citations (3)
| Title |
|---|
| POELMA R H等: "Mechanics of Graphene and Carbon Nanotubes Under Uniaxial Compression and Tension", 《SPRINGER INTERNATIONAL PUBLISHING》 * |
| QINGHUA LI等: "rogress in Research on Carbon Nanotubes Reinforced Cementitious Composites", 《ADVANCES IN MATERIALS SCIENCE AND ENGINEERING》 * |
| 杨健辉: "高强钢纤维碳纳米管混凝土双轴受压试验与破坏准则", 《土木工程学报》 * |
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