CN109834247A - A kind of negative poisson's ratio open celled foam aluminum material and its Seepage Foundry preparation method - Google Patents
A kind of negative poisson's ratio open celled foam aluminum material and its Seepage Foundry preparation method Download PDFInfo
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- CN109834247A CN109834247A CN201910032411.1A CN201910032411A CN109834247A CN 109834247 A CN109834247 A CN 109834247A CN 201910032411 A CN201910032411 A CN 201910032411A CN 109834247 A CN109834247 A CN 109834247A
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Abstract
The invention discloses a kind of open celled foam aluminum material and its Seepage Foundry preparation method with negative poisson's ratio characteristic, first cell wall of Open-cell Aluminum Foam material internal structure cell is in inner concavity, to have negative poisson's ratio characteristic.Open-cell Aluminum Foam with negative poisson's ratio characteristic material when by extraneous load can concentrate at load automatically, can make full use of the mechanical characteristic of material, more effectively resistance to deformation and can absorb energy compared with the regular-type foam aluminium of positive Poisson's ratio.The Open-cell Aluminum Foam the preparation method is as follows: first passing through infiltration casting is made common open celled foam aluminum material, then under aluminium fusing point at a temperature of by triaxial compressions to which the open celled foam aluminum material with negative poisson's ratio characteristic be made.
Description
Technical field
The present invention relates to a kind of foamed aluminium material and preparation method thereof more particularly to a kind of negative poisson's ratio open celled foam aluminiums
Material and preparation method thereof.
Background technique
Negative poisson's ratio material is also known as auxetic materials (Auxetic), is the special material that a kind of Poisson's ratio is negative, works as material
When stretcher strain occurs for material, lateral expansion can occur perpendicular to the direction of load；And when compressive deformation occurs for material, perpendicular to
The direction of load can occur laterally to shrink.Since there is negative poisson's ratio material unique negative poisson's ratio characteristic and material to concentrate effect
It answers, makes it in terms of modulus of shearing, Resisting fractre toughness, resistance to indentation and energy absorption and shock resistance all than identical group
It is more excellent at, the positive Poisson ratio material of equal densities.Negative poisson's ratio material currently used for safeguard structure is mainly negative Poisson
Than fine structure material, most of microscopical structures are in inner concavity, although it is with very strong shock resistance, processing method
Complexity and high cost limit a possibility that it is further applied.
On the other hand, foamed aluminium be it is a kind of using aluminum or aluminum alloy as skeleton, containing the three-dimensional porous metal material of a large amount of hilums,
Have many advantages, such as low-density, high specific stiffness, buffering antidetonation, corrosion-resistant and unique skin effect, and its porous structure and
Metallic character allow foamed aluminium energy absorption, sound-absorbing sound insulation and in terms of have excellent performance, make its automobile,
Aviation, building etc. are widely used.Foamed aluminium can be divided into open celled foam according to whether hilum unit is interconnected
Aluminium and closed-cell aluminum foam two major classes are used widely it in terms of sound absorption due to the pore structure of Open-cell Aluminum Foam connection,
Closed-cell aluminum foam is commonly used in sound insulation, furthermore the specific stiffness of closed-cell aluminum foam, specific strength phase since hole is mutual independence
Higher than in Open-cell Aluminum Foam, cushion energy absorbing property is also stronger.Closed-cell aluminum foam mainly passes through foam melt method, gas injection foaming
Prepared by the methods of method and powder metallurgic method, bubble phase is ensured when generating bubble to stabilization and is not spilt over, aperture
Foamed aluminium is then mainly prepared by infiltration casting and model casting hair.For foamed aluminium material, relative density is it
One important structural characteristic parameter, it has the mechanical property (such as Young's modulus, yield strength) of foamed aluminium material larger
It influences.Relative density is bigger, and intensity is higher.
The Poisson's ratio of foamed aluminium is positive value, if its negative poisson's ratio can be made to become negative value by certain preparation method, solely
When special negative poisson's ratio characteristic can make it by impact loading, material can concentrate on automatically load place from surrounding, improve
The relative density of part enables material by absorbing more energy to further increase local strength.Furthermore negative Poisson
Than Open-cell Aluminum Foam rigidity also can the nonlinear raising with the increase of shock loading, be able to bear bigger load, because
This is with huge science and engineering significance.
It is involved in the present invention to be opened to negative poisson's ratio when foamed aluminium material is as a kind of buffering energy-absorbing component or materials'use
Hole foamed aluminium is prepared by traditional positive Poisson's ratio Open-cell Aluminum Foam, and inner concavity is presented in internal member cell wall, it is possible to
Realize smaller interstitial space in unit length material microstructure, the totality that foamed aluminium material not only can be improved in this is relatively close
Degree, and when traditional foamed aluminium material is filled into other components as a kind of packing material of buffering energy-absorbing, due to
The interstitial space of foamed aluminium is larger, even if the lateral expansion for reaching dense area (material is compacted) when compressed is smaller, makes
There are larger white space between foamed aluminium and component, the ability of component buffering energy-absorbing is reduced, and negative poisson's ratio open celled foam
Aluminium is exactly the opposite, lesser interstitial space, when it is compressed to dense area, can produce biggish lateral expansion, subtracts significantly
Small white space between foamed aluminium and component, improves the ability of component buffering energy-absorbing.
Summary of the invention
The technical problem to be solved by the present invention is to provide a kind of negative Poisson for defect involved in background technique
Than open celled foam aluminum material and its Seepage Foundry preparation method, the characteristic of material concentration can be generated, greatly improve its intensity,
Mechanical properties such as energy-absorbing etc..
The present invention uses following technical scheme to solve above-mentioned technical problem:
First cell wall of a kind of negative poisson's ratio open celled foam aluminum material, open celled foam aluminum material cellular is in inner concavity, so that opening
Hole foamed aluminium material has negative poisson's ratio characteristic.
The invention also discloses a kind of Seepage Foundry preparation methods of negative poisson's ratio open celled foam aluminum material, comprising following
Step:
Step 1) prepares mold, heat-resistant filler and solvent soln；The mold upper end opening, lower end are ventilative bottom plate；Institute
The fusing point for stating heat-resistant filler is higher than the fusing point of aluminium；The solvent soln can dissolve heat proof material and not send reaction with aluminium；
Step 2) is inserted on the ventilative bottom plate of mold bottom after heat-resistant filler is processed into porous preforming block, or will be resistance to
The particle of hot filler is placed on the ventilative bottom plate of mold bottom and the particle of heat-resistant filler and mould inner wall is come into full contact with；
Step 3) is heated to preset first temperature threshold to the heat proof material in mold, is subsequently poured into liquid aluminum melt；
Step 4), between making aluminum melt fully penetrate into heat-resistant filler in such a way that top compression and bottom vacuum inhale casting
Gap obtains the Open-cell Aluminum Foam with heat-resistant filler after cooled and solidified；
Open-cell Aluminum Foam with heat-resistant filler is put into solvent soln and heat-resistant filler is dissolved by step 5), is opened
Hole foamed aluminium；
Open-cell Aluminum Foam is heated to preset second temperature threshold value and kept the temperature by step 6), and described preset second
Temperature threshold is less than the melting temperature of aluminium；
Step 7) carries out triaxial compressions to Open-cell Aluminum Foam and brings it about plastic deformation, generates the open-celled structure of concave shaped；
Open-cell Aluminum Foam after triaxial compressions is cooled to room temperature by step 8), obtains negative poisson's ratio open celled foam aluminum material.
It is described resistance to as a kind of further prioritization scheme of Seepage Foundry preparation method of open celled foam aluminum material of the present invention
Hot filler uses NaCl, and the solvent soln uses water.
It is preset as a kind of further prioritization scheme of Seepage Foundry preparation method of open celled foam aluminum material of the present invention
500~730 degrees Celsius of the range of first temperature threshold.
It is described pre- as a kind of further prioritization scheme of Seepage Foundry preparation method of open celled foam aluminum material of the present invention
If second temperature threshold value range be 500~600 degrees Celsius.
As a kind of further prioritization scheme of Seepage Foundry preparation method of open celled foam aluminum material of the present invention, the step
When rapid 7) middle progress triaxial compressions, compressed simultaneously using three axis of the triaxial compressions equipment to Open-cell Aluminum Foam.
As a kind of further prioritization scheme of Seepage Foundry preparation method of open celled foam aluminum material of the present invention, the step
Specific step is as follows for rapid 7) middle progress triaxial compressions:
The first normal orientation, the second normal orientation, third normal orientation is enabled to be mutually perpendicular to；
Step 7.1) compresses preset first distance threshold value to Open-cell Aluminum Foam in the first normal orientation；
Step 7.2) compresses preset second distance threshold value to Open-cell Aluminum Foam in the second normal orientation；
Step 7.3) compresses preset third distance threshold to Open-cell Aluminum Foam in third normal orientation；
Step 7.4) repeats step 7.1) to step 7.3) n times, and N is preset the number of iterations threshold value.
The invention adopts the above technical scheme compared with prior art, has following technical effect that
Open celled foam aluminum material made of the present invention shows Negative poisson's ratio in deformation process, to generate material
The characteristic of concentration improves the density in region loaded, can greatly improve the mechanical properties such as its intensity, energy-absorbing.
Detailed description of the invention
Fig. 1 (A), Fig. 1 (B) be respectively traditional open celled foam aluminum material, the present invention in negative poisson's ratio open celled foam aluminum material
Structure cell theory schematic diagram；
Fig. 2 (A), Fig. 2 (B) be respectively traditional open celled foam aluminum material, the present invention in negative poisson's ratio open celled foam aluminum material
Deformation schematic diagram when by concentrfated load；
Fig. 3 is the Seepage Foundry preparation method schematic diagram of negative poisson's ratio Open-cell Aluminum Foam in the present invention.
Specific embodiment
The invention discloses a kind of negative poisson's ratio open celled foam aluminum materials, and the open celled foam aluminum material of preparation is in deformation process
Middle presentation Negative poisson's ratio can greatly improve the mechanical properties such as its intensity, energy-absorbing to generate the characteristic of material concentration
Deng.
A specific embodiment of the invention is further detailed with reference to the accompanying drawing.
The invention discloses a kind of negative poisson's ratio open celled foam aluminum material, first cell wall of internal structure cell is in indent
Shape, to have negative poisson's ratio characteristic.
Fig. 1 (A) illustrates the structure cell theory schematic diagram of traditional open celled foam aluminum material；Fig. 1 (B) illustrates negative Poisson
Than the structure cell theory schematic diagram of open celled foam aluminum material, inner concavity is presented.Plane between Fig. 1 (A) and (B) central sill is
Perforation, the space of foamed aluminium cellular is interconnected.
Fig. 2 (A) illustrates deformation schematic diagram of conventional foam aluminium when by concentrfated load, and material flow direction is remote
From loading direction；Fig. 2 (B) illustrates deformation schematic diagram of negative poisson's ratio Open-cell Aluminum Foam when by concentrfated load, material
Flow direction is close loading direction, therefore can more effectively resist impact.
Fig. 3 illustrates the Seepage Foundry preparation method of negative poisson's ratio open celled foam aluminum material: first preparation mold, heat-resisting fill out
Material and solvent soln；Mold upper end opening, lower end are ventilative bottom plate；Heat-resistant filler uses NaCl, and solvent soln uses water；It will be resistance to
Hot filler is inserted on the ventilative bottom plate of mold bottom after being processed into porous preforming block, or the particle of heat-resistant filler is placed in mold
On the ventilative bottom plate of bottom and the particle of heat-resistant filler and mould inner wall are come into full contact with；Heat proof material in mold is added
Heat is subsequently poured into liquid aluminum melt to 500~730 degrees Celsius, keeps aluminium molten in such a way that top compression and bottom vacuum inhale casting
Body fully penetrates into filler space, obtains Open-cell Aluminum Foam after cooled and solidified, being subsequently placed into water dissolves filler.By open celled foam
Aluminium keeps the temperature a certain temperature to aluminium fusing point, triaxial compressions is carried out to foamed aluminium using triaxial compressions equipment, thus in generating
The open-celled structure of spill, and be cooled to room temperature, obtain negative poisson's ratio open celled foam aluminum material.
When being maintained at 500~600 degrees Celsius when triaxial compressions, the negative poisson's ratio value of negative poisson's ratio Open-cell Aluminum Foam obtained
It is minimum.
When carrying out triaxial compressions, it can be compressed simultaneously using three axis of the triaxial compressions equipment to Open-cell Aluminum Foam,
It can be compressed step by step, the specific steps are as follows:
The first normal orientation, the second normal orientation, third normal orientation is enabled to be mutually perpendicular to；
Step 7.1) compresses preset first distance threshold value to Open-cell Aluminum Foam in the first normal orientation；
Step 7.2) compresses preset second distance threshold value to Open-cell Aluminum Foam in the second normal orientation；
Step 7.3) compresses preset third distance threshold to Open-cell Aluminum Foam in third normal orientation；
Step 7.4) repeats step 7.1) to step 7.3) n times, and N is preset the number of iterations threshold value.
Manufactured negative poisson's ratio Open-cell Aluminum Foam shows Negative poisson's ratio in deformation process, to generate material collection
In characteristic, improve the density in region loaded, the mechanical properties such as its intensity, energy-absorbing can greatly be improved.
Those skilled in the art can understand that unless otherwise defined, all terms used herein (including skill
Art term and scientific term) there is meaning identical with the general understanding of those of ordinary skill in fields of the present invention.Also
It should be understood that those terms such as defined in the general dictionary should be understood that have in the context of the prior art
The consistent meaning of meaning will not be explained in an idealized or overly formal meaning and unless defined as here.
Above-described specific embodiment has carried out further the purpose of the present invention, technical scheme and beneficial effects
It is described in detail, it should be understood that being not limited to this hair the foregoing is merely a specific embodiment of the invention
Bright, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done should be included in the present invention
Protection scope within.
Claims (7)
1. a kind of negative poisson's ratio open celled foam aluminum material, which is characterized in that first cell wall of open celled foam aluminum material cellular is in indent
Shape, so that open celled foam aluminum material has negative poisson's ratio characteristic.
2. the Seepage Foundry preparation method based on negative poisson's ratio open celled foam aluminum material described in claim 1, which is characterized in that
It comprises the steps of:
Step 1) prepares mold, heat-resistant filler and solvent soln；The mold upper end opening, lower end are ventilative bottom plate；It is described resistance to
The fusing point of hot filler is higher than the fusing point of aluminium；The solvent soln can dissolve heat proof material and not send reaction with aluminium；
Step 2) is inserted on the ventilative bottom plate of mold bottom after heat-resistant filler is processed into porous preforming block, or is filled out heat-resisting
The particle of material is placed on the ventilative bottom plate of mold bottom and the particle of heat-resistant filler and mould inner wall is come into full contact with；
Step 3) is heated to preset first temperature threshold to the heat proof material in mold, is subsequently poured into liquid aluminum melt；
Step 4) inhales the gap for making aluminum melt fully penetrate into heat-resistant filler by the way of casting using top compression and bottom vacuum, cold
But the Open-cell Aluminum Foam with heat-resistant filler is obtained after solidifying；
Open-cell Aluminum Foam with heat-resistant filler is put into solvent soln and heat-resistant filler is dissolved by step 5), obtains aperture bubble
Foam aluminium；
Open-cell Aluminum Foam is heated to preset second temperature threshold value and kept the temperature by step 6), the preset second temperature
Threshold value is less than the melting temperature of aluminium；
Step 7) carries out triaxial compressions to Open-cell Aluminum Foam and brings it about plastic deformation, generates the open-celled structure of concave shaped；
Open-cell Aluminum Foam after triaxial compressions is cooled to room temperature by step 8), obtains negative poisson's ratio open celled foam aluminum material.
3. the Seepage Foundry preparation method of negative poisson's ratio open celled foam aluminum material according to claim 2, which is characterized in that
The heat-resistant filler uses NaCl, and the solvent soln uses water.
4. the Seepage Foundry preparation method of negative poisson's ratio open celled foam aluminum material according to claim 2, which is characterized in that
500~730 degrees Celsius of the range of preset first temperature threshold.
5. the Seepage Foundry preparation method of negative poisson's ratio open celled foam aluminum material according to claim 2, which is characterized in that
The range of the preset second temperature threshold value is 500~600 degrees Celsius.
6. the Seepage Foundry preparation method of negative poisson's ratio open celled foam aluminum material according to claim 2, which is characterized in that
When carrying out triaxial compressions in the step 7), compressed simultaneously using three axis of the triaxial compressions equipment to Open-cell Aluminum Foam.
7. the Seepage Foundry preparation method of negative poisson's ratio open celled foam aluminum material according to claim 2, which is characterized in that
Triaxial compressions are carried out in the step 7), and specific step is as follows:
The first normal orientation, the second normal orientation, third normal orientation is enabled to be mutually perpendicular to；
Step 7.1) compresses preset first distance threshold value to Open-cell Aluminum Foam in the first normal orientation；
Step 7.2) compresses preset second distance threshold value to Open-cell Aluminum Foam in the second normal orientation；
Step 7.3) compresses preset third distance threshold to Open-cell Aluminum Foam in third normal orientation；
Step 7.4) repeats step 7.1) to step 7.3) n times, and N is preset the number of iterations threshold value.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110666139A (en) * | 2019-10-25 | 2020-01-10 | 清华大学 | Foam metal preparation device and preparation method and foam metal |
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| US20110109005A1 (en) * | 2009-11-06 | 2011-05-12 | Rolls-Royce Plc | Method of manufacturing a foam |
| US20110282452A1 (en) * | 2008-11-10 | 2011-11-17 | Friedrich-Alexander-Universitat Erlangen-Numberg | Auxetic material |
| CN104004937A (en) * | 2014-05-04 | 2014-08-27 | 昆明理工大学 | Preparation method of high-porosity through-hole aluminum or aluminum alloy foam |
| CN104681821A (en) * | 2013-12-03 | 2015-06-03 | 罗伯特·博世有限公司 | Battery cell having auxetic component |
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Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4668557A (en) * | 1986-07-18 | 1987-05-26 | The University Of Iowa Research Foundation | Polyhedron cell structure and method of making same |
| US20100029796A1 (en) * | 2005-11-04 | 2010-02-04 | Auxetic Technologies Limited | Process for the preparation of auxetic foams |
| CN101260490A (en) * | 2008-04-17 | 2008-09-10 | 西北工业大学 | Porous aluminum alloy with micron-stage pore and preparation method thereof |
| US20110282452A1 (en) * | 2008-11-10 | 2011-11-17 | Friedrich-Alexander-Universitat Erlangen-Numberg | Auxetic material |
| US20110109005A1 (en) * | 2009-11-06 | 2011-05-12 | Rolls-Royce Plc | Method of manufacturing a foam |
| CN104681821A (en) * | 2013-12-03 | 2015-06-03 | 罗伯特·博世有限公司 | Battery cell having auxetic component |
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| CN110666139A (en) * | 2019-10-25 | 2020-01-10 | 清华大学 | Foam metal preparation device and preparation method and foam metal |
| CN110666139B (en) * | 2019-10-25 | 2020-12-25 | 清华大学 | Foam metal preparation device and preparation method and foam metal |
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Application publication date: 20190604 |