THE MADE FOAM ALUMINIUM.
THE MADE FOAM ALUMINIUM.
Last years heightened interest to two is shown
To porous materials on the basis of the aluminium, possessing many
Attractive properties. A material with close pores,
Received by a method of foaming fused or
The semifused aluminium, name penoaljuminiem. Another
Material with the open time, called by porous aluminium,
Receive a method of foundry manufacture with use
Deleted napolnitelja or by a galvanic covering on
Deleted then penopoliuretane.
PENOALJUMINY.
Properties penoaljuminija.
During researches penoaljuminija at Institute of the perspective
Materials it. Fraungofera (Germany) it is established, that to the dress
With teploizoljatsionnymi and sound-proof properties
penoaljuminy shows at deformation strongly nonlinear
Behaviour, characteristic for porous structures. This property
Can be used for dempfirovanija blow. Electric
And thermal conductivity has less, than at the continuous
Metal, but lay in the field of properties of the usual metal
Materials. As well as the made foam plastic, metal foams
Possess excellent energoabsorbirujushchimi properties, but on
Higher level of durability. Wide temperature area
Applications and negorjuchest a material are others it
Advantages. Good retsikliruemost penoaljuminija
Represents not less valuable parametre. A material well
It is processed pileniem, drilling, milling, turning.
As ways of connection can be used
Pasting, the soldering or special welding.
Unlike cellular concrete and drevesnostruzhechnyh plates at
penoaljuminija low hygroscopicity (1 3 %), that
Causes frost resistance and absence of cracks at difference
Temperatures. It is not necessary to impregnate it with antiseptics and
antipirenami. On its surface are freely pasted
Various decorative materials, he well perceives
Paint.
Application.
Aluminium foams are used for protection against blow, for
Increases of rigidity of hollow profiles, for manufacturing of the nonflammable
Front elements of buildings and easy and fire-resistant cabins of lifts,
In manufacture teplostojkih dempfirujushchih materials, for
Hardenings of anchors in concrete walls.
The greatest interest to penoaljuminiju is shown by the foreign
avtomobilestroiteli. In 1998 on autoshow in Detroit
Wilhelm Karmann has presented a novelty, in which at
Body manufacturing the three-layer aluminium were used
Sheets with aluminium foam (AFS - Aluminium Foam Sandwich).
Such material possesses high specific rigidity, small
Thermal and electric conductivity, does not burn and it is good
Approaches for absorption or dempfirovanija to energy. Low
The weight of a similar design reduces the gasoline expense. A body on
50 % are easier corresponding steel, but in 10 times is stabler.
Three-dimensional multilayered structures strengthen rigidity of a frame, from
Them it is possible to make also a back wall of a body and sitting.
Karmann offers idea of the safe car of the XXI-st century, in
Which flat aluminium elements will be used not,
And three-dimensional multilayered details with penoaljuminiem - from doors
To difficult group of the bottom. Such details very easy also have in
15 times higher rigidity, than the usual sheet
Designs. Advantages penoaljuminija on shumoglusheniju are appreciable
At the raised frequencies (more than 800 Hz).
Firm Neuman Alufoam (Austria) makes of the aluminium
Foams the case not loaded details of cars and gasiteli
Lateral blow which are pawned in lateral doors.
Density of details from penoa ljuminija - 0,5-0,6/sm3
It is noticed, that the closed external cover surrounding porous
Structure, provides repeatedly higher rigidity,
Than structures with open porosity. The firm lets out also
Details of a body and the running part, working on a bend and torsion
For strengthening of their rigidity. Besides, penoaljuminy can
To be used as foundry cores. After moulding they
Remain in ready shaped casting instead of emptiness, which
Are provided for simplification of the car that gives the defined
Advantages in durability also reduces expenses for removal
Usual sandy cores.
Penomaterialy firms Cymat in the form of profiles of the rectangular
Sections are used for shock-absorbers of doors automobile
Cars and emergency partitions. Unlike the cellular
Designs of an aluminium material penoaljuminy izotropen and
Can resist to blow under any corner.
Penoaljuminy it is applied in building in the form of the fireproof
Partitions and a facing material.
Firm Alulight International GmbH created recently by
Associations of capitals of some the German and Austrian companies,
Offers following kinds of products from a material alutigtrt,
Which represents penoaljuminy in density from 300 to
1000 kg/m3:
- Case shumozaglushajushchie details;
- Electromagnetic screens in the form of wall and ceiling
The plates protecting from penetration or radiations
Electromagnetic waves frequency from 0,1 to 1000 MHz, and also
Cases of electronic devices;
- Thermal screens;
- Easy building material as fireproof alternative
To tree and plastic (it can be delivered in the form of plates with
In the maximum sizes 625я 625 mm, thickness from 8 to 25 mm);
- gasiteli blow for automobile and rail
Transport;
- shumogasiteli, working in heavy conditions (the high
Temperature, humidity, dust, vibration), in sterile or
Fire-dangerous premises (planes, hotels, department stores,
Industrial buildings).
At exhibition Aluminium ' 2000 in Essen it has been presented
Novelty - a plate from penoaljuminija with the durability similar
Durabilities of the reinforced concrete. Firm Alulight specifies
Following possible scopes of such plates:
- Building and architecture (shops, booths, racks,
Tables, furniture, exhibition stands, internal and external
Facades, dividing partitions, ceilings and floors);
- Transport and mechanical engineering (walls of rail transport,
The ships, systems of safety and superstructures for the automobile
Motor vehicles, aviacontainers, trollei, the bases of cars,
Directing elements, shumozashchitnye caps).
Way of manufacturing.
The greatest distribution was received by the developed
Institute Fraungofera the powder "know-how"
penoaljuminija. As an initial material are used
Powders of aluminium or aluminium alloys which mix up
With poroforom (substance, at heating allocating the gas
Component), for example hydride of the titan. A share porofora
It is insignificant and makes, as a rule, less than 1 %.
The prepared mix is condensed by hot pressing.
Preliminary preparation looks like prutka or a profile.
Preparation outwardly does not differ from Usual metal and can in
Further to be deformed in a half-finished product prokatkoj or
Pressing depending on a kind final made foam
Products. The received half-finished product is exposed to operation
Foaming by heating to the temperature close to
To temperature of fusion of a used alloy. In these conditions
Allocated as a result of thermal decomposition porofora gas
Forms in metal foamy structure. After achievement
Desirable increase in volume process comes to an end with cooling
Material, and the foamy structure is stabilised. Thus
Close pores are formed. The density penoaljuminija can
To make from 0,4 to 1/sm3
For manufacturing of shaped details the various is used
Technics of foaming. For example, for reception of details of the difficult
The form close to a final product, the hollow are applied
Steel, folding forms in which it is pawned
Certain quantity of the pressed preparation with poroforom.
At heating to specified above temperature foam fills
The form free space, and after cooling turns out
Desirable detail with the closed porosity. Approximately as it is possible
To make the hollow profiles filled with foam or pipes, in
Result of that at small weight considerably raise
Rigidity of details and them energoabsorbirujushchie properties. From
prokatannoj in sheets of preliminary preparation by
Foaming receive plates of a various thickness. It is possible also
To make three-layer (sandvichevye) structures, in which
External layers consist of continuous metal (for example,
Aluminium alloy), and a core - from penoaljuminija. By
Deformations before foaming of multilayered preparation in
The three-dimensional half-finished product is received also by lungs sandvichevye
Designs of the difficult form.
Company Cymat Aluminium under firm Alcan licence
International has begun manufacture penomaterialov on the
New line in the Valve (piece of Ontario, Canada). Thus
The way developed by company Norsk-Hydro is used, at
Which in rasplav aluminium with added in it for increase
Viscosity by particles oksida aluminium and silicon carbide it is blown
With the help impellera gas. Foam arising on a surface
Acts in film a conveyor tape in the form of a made foam plate,
Which porosity can vary from 80 to 97 %. Initial
The material price - $8-11 for 1 kg. Firm Alcan uses to 15 %
Ceramic particles for the purpose of stabilisation penomateriala and
Prevention of its destruction, and thus company Cymat
Plans to carry out the density control penomateriala with
Error of 0,5 % from the set.
In Russia manufacture penoaljuminija has been mastered for the first time in
VILSe. There the powder technology is used, are made
Sheets and plates in the thickness from 3 to 85 mm, width to 1000 mm.
The density penoaljuminija can make from 0,3 to 2/sm3
Pilot production of details from penoaljuminija the powder
By way it is mastered also on Kamensk-Uralsk the metallurgical
Factory. Plates, shaped products have been let out, and also
The pipes filled with aluminium foam.
POROUS ALUMINIUM.
Properties.
The density of porous aluminium lays usually in a range from
0,9 to 1,2 g/sm3 that corresponds to porosity from 55 to 67 %.
Mechanical properties of this material were studied to the last
Time not so intensively, as penoaljuminija. Mechanical
Its behaviour is rather close to what foams have with
The closed porosity: initial, almost linear lifting
Pressure it is replaced by area of the considerable plastic
Deformations and then at very big deformation passes in
Consolidation of all structure at corresponding high efforts.
They are required to deform porous structure. Such
In the image, the material possesses high rigidity. Durability on
Compression corresponds almost to the same values, as at
penoaljuminija.
Permeability.
For many spheres of application it is desirable supervised and
Operated permeability of a material gases or liquids.
Porous aluminium has the high developed internal
The surface making at density of 1,1 g/sm3 from 1 to 2
б 2 This property can be used in the compact
Heat exchangers.
Acoustic characteristics.
These indicators are a little bit worse, than at the special
shumogasjashchih materials, however porous aluminium has much
Other useful properties (negorjuchest, high firmness to
To temperature changes, negigroskopichnost, etc.), which
Do favourable its application for shumoglushenija.
Application possibilities.
Porous metals, for example spechennaja bronze, are used
For a long time already. Therefore possible scopes of the porous
Aluminium are similar.
- SHumoglushiteli. Porous aluminium is used in
Designs shumoglushitelej, in which by dekompressii noise,
Arising from a gas exit, decreases (for example, in
Pneumatic installations and compressors). SHumogasjashchie
The elements made from leaky spechennyh of powders of bronze
Or steels, are expensive enough. The porous aluminium received
In the foundry way, can be jointed at manufacturing with
Continuous metal with a carving, and connection with a gas exit at
It becomes simple. The first technical tests
Have shown, that at least the same thus are reached
Results, as at spechennoj bronze.
- Filters. A scope of porous aluminium.
As filters it is wide enough. Them it is possible to separate
Firm parts, for example soot, from liquids or gases.
- Carriers of catalysts. Owing to the developed internal
Surfaces in a combination with good permeability the porous
Aluminium can be used as a bearing lattice for
Catalysts. High heat conductivity of a material has
Value at strong ekzotermicheskih reactions, for example, at
Oxidation etilena in etilenoksid.
- Heat exchangers. High heat conductivity of aluminium
Assumes use of porous designs from this
Metal with the developed surface for heat exchange between
Liquids, gases or between a liquid and gas. Firm ERG
Materials and Aerospace (Oakland, piece California, the USA)
Makes porous aluminium which is used in
Compact nizkotemperaturnyh heat exchangers for
Artificial companions of the earth.
- Other scopes. Porous materials, in that
Number aluminium, can be used as stores
Liquids for its subsequent dosed out giving, for example, in
Porous valkah, in details of bearings of sliding (a time
Fill with greasing). At gas giving through porous materials
It it is possible in the distributed kind barbotirovat in a liquid or with
The help of an air cushion to create a sliding surface
(The air bearing). At last, porous aluminium thanking
The heat conductivity it is used in designs
plamjagasitelej.
Way of manufacture.
The way known for a long time consists in pouring of a capsule with
napolnitelem the fused metal. After removal
napolnitelja there is a body with opened on rami, connected
Among themselves. By a choice napolnitelja it is possible to vary
Density of a material and morphology of a time over a wide range. In
The past the materials made on this way had
Lacks (for example, the rests napolnitelja, neoterminated
Filling of intervals between particles napolnitelja), or
Manufacturing process had negative influence on
Environment. New variants of this way allow
To overcome the specified lacks. According to such scheme process
Manufactures it is subdivided into the following of 4 stages.
1. Preparation napolnitelja, thus preferably
To apply inorganic granules, but it is possible to use also
zasypku from organic materials.
2. Infiltratsija zasypki napolnitelja metal. That
To provide through filling of intervals between granules,
infiltratsiju spend under the raised pressure or under
razrjazheniem.
3. Material removal napolnitelja by dissolution or
vybivanija.
4. Turning of the received porous preparation, is sharp on
The demanded sizes or another mehanoobrabotka.
Advantages of the specified way:
- Initial materials are rather inexpensive - as
napolnitel, and aluminium which can be used in
Kind low-grade lomov and a waste;
- Does not pollute environment, at a careful choice
napolnitelja there are no appreciable pollution by products
krekinga or dissolution;
- retsikliruemost: the material can be used
Completely again, as usual cast details;
- The jointed structures can be made: at moulding in
One cycle probably strong connection porous and continuous
Materials;
- Possibility of giving to a product of the final form.
In Russia the manufacturing techniques of porous aluminium were
It is developed on chair of foundry manufacture Ural
Polytechnical institute. With assistance of UPI on KUMZe was
Release of various details from porous aluminium is mastered. A method
kokilnogo moulding round ingots in diameter 100 have been made
And 200 mm, and also flat ingots in the sizes 100я 500я 800 mm and
200я 500я 800 mm. After machining also were sharp
Porous disks and Plates of the various sizes with two are received
Kinds of a time of 0-1,4 mm and 1,4-5 mm. Porosity of the received details
Made 52-61 %, material density - from 1,04 to 1,38
/sm3
The conclusion.
Despite advantages of application of the described new
Materials in mechanical engineering, building, the electrical engineer and
Other industries, scales of their introduction in
Present time are insignificant. The "know-how" penoaljuminija
And porous aluminium still is at an initial stage
The formation, and it is necessary for improving.
For example, operation of foaming of intermediate preparation at
Powder way of manufacture penoaljuminija demands creation
New, not having analogues of the thermal unit. For
Workings out and constructions of such unit are necessary
Considerable means which can be allocated only at
Condition long-term and enough volume orders on
penoaljuminy.
Manufacturing on KUMZe samples of products from penoaljuminija and
Porous aluminium has allowed to define key parametres
Technologies of their manufacture. Thus substantially
The available equipment is used. Creation is planned
Specialised sites on manufacture penoaljuminija and
Porous aluminium on the existing areas pressovogo and
Foundry shops. Now business behind consumers of these
Perspective materials.
Physicomechanical properties penoaljuminija and other porous
Materials.
Property Penoaljuminy Aluminium п п 31 Drevesno - the Oak plate the Plate from
(Density - 0,7-0,8 g/sm3) struzhechnaja a foam concrete plate
Density, g/sm3 0,3-2 2,7 0,25-1,1 0,69 0,3-1,2
Hygroscopicity, % 1-3 - 4-6 12 28-40
Durability, Mpa 45 250 0,4-3,5 5-123 0,8-80
The module the Ship's boy, Mpa 45OO0 70OO0 0,4-35 107,7 1700-7500
Heat conductivity, Vt (m) 4-5 140 0,046-0,18 0,35 0,12-0,37
Relative lengthening, % 0,3-1 10-15 - - -
Zvukoprovodnost, DB/SM 1,1 50 - 2,4 -
Specific properties Nonflammable, - Trudnogorjuchy, Combustible, at Nonflammable,
Ecologically pure at burning burning the big allocates
Will allocate fonoly carbonic oxide hygroscopicity
S.Tsukrov,
k.t.n., the Moscow representation of Open Society "п пёп п ".
//* an information Source: metallosnabzhenie and sale, 30.10.00
//* Reg. Nom. - 1101000007.13-------------------------------------------
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