JPH01100204A - Porous aluminum or aluminum alloy body - Google Patents

Abstract

PURPOSE:To improve the heat and weather resistances of a porous body by compression-working an Al material mixed with an inorg. binder and specifying the porosity by hardening. CONSTITUTION:Powdery or fibrous Al or Al alloy is mixed with an inorg. binder such as sodium silicate. The mixture is compression-worked at >=90% rate and hardened by heating to obtain a lightweight porous body having 30-96% porosity. This porous body has high gas permeability and a significant sound absorbing effect and can be utilized as a sound absorbing material, a filter, a heat exchanger, etc.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention uses aluminum or its alloys in various forms such as powder and fiber, and combines them with an inorganic binder to produce sound absorbing materials, filters, and heat exchangers. The present invention relates to a porous body having a porosity of 30% to 96%, which is excellent in weather resistance, economical efficiency, etc. and can be used for containers and the like.

(Prior art) Sintered materials have been developed that use spherical, rod-shaped, or elliptical aluminum or alloys thereof, and use metal or organic materials as binders, and can be used for applications such as sound-absorbing materials, filters, and heat exchangers. .

[Problem that the invention seeks to solve]

A porous body made of aluminum or its alloy and sintered with a metal binder has the disadvantage that only a certain range of shapes can be used for the aluminum and its alloy.

In other words, in the case of a porous body using a metal binder, a powdery material made of aluminum or its alloy is mixed with a powdery material made of an aluminum alloy whose melting point is 10°C or more lower, and heated at a temperature intermediate between the melting points of the two. However, in this case, in order to control the shape of the pores, there are some restrictions on the shape of the aluminum or aluminum alloy used as the material. Furthermore, when sintering with a metal binder, it is necessary to use flux or a heating furnace whose atmosphere can be adjusted in order to remove the oxide film on the material and suppress its formation.

Therefore, when a metal binder is used, there are many disadvantages in terms of usage, such as high manufacturing costs and large restrictions on shape.

Further, in the case of a porous body using an organic binder, the high temperature strength is also insufficient.

(Means for solving problems) The present invention solves these problems and provides a powder-like product.

This was the result of extensive research to develop a lightweight porous body that is highly heat resistant, weather resistant, and highly breathable, using aluminum or its alloys in all forms, including fibrous forms.

That is, the present invention uses powdered or fibrous aluminum or aluminum alloy mixed with an inorganic binder to contain 90%
Rapidly hardened with the following compression processing, porosity 30-96%
It is characterized by the following.

[For production]

When an inorganic binder is used in this way, there is no limit to the shape of aluminum or its alloy used as a material, and not only can the material be supplied at a low cost, but also the shape of the pores and the porosity can be set freely. That is, in the present invention, control of porosity is achieved not only by changing the shape of aluminum or its alloy used as a material, but also by applying pressure during mixing with an inorganic binder and curing. In addition, if water glass (sodium silicate, potassium silicate, lithium silicate, etc.), ethyl silicate, acidic metal phosphate (aluminum phosphate, magnesium phosphate, etc.) or colloidal silica is used as an unmodified binder, it will be non-flammable.・Excellent heat resistance. It is hard and has excellent wear resistance. It becomes possible to produce a porous body that has characteristics such as low thermal expansion, little blistering and peeling, non-toxicity, very easy handling, and low cost.

The porous body of the present invention can be made of aluminum C-shim or its alloy in various shapes such as powder or fiber, and can be mixed with an inorganic binder and pressurized before hardening to change the shape of the pores and the porosity. can be set freely, and is nonflammable and heat resistant.

Weather resistant 2 strength, lightweight, low thermal expansion, non-toxic, inexpensive.

Porous bodies with a porosity of 30% to 96% can be obtained, with no restrictions on the dimensions and shapes that can be manufactured, so they have a wide range of uses such as sound absorbing materials, filters, and heat exchangers. .

(Example〕 Next, examples of the present invention will be described.

Example-1 A1-4% Mg alloy φ50m 9 rods cut m1 with a lathe
．． Long chips obtained by cutting with OMM are mixed with aluminum phosphate as an inorganic binder, and after applying a load of 2 tons, the aluminum phosphate is hardened by heating to 300 ° C.
A porous body with a thickness of 0m x width of 20Os x length of 200m was prepared. Sufficient breathability can be confirmed by water pressure, and the porosity is 8.
It was 1%.

Example-2 Industrial pure aluminum φ50HR round bar cut with a lathe ω
After cutting the chips obtained by cutting with 0.5 inch into a length of about 10 m, they were mixed with sodium silicate as an inorganic binder,
After applying a load of 0.3 tons, heat to 80°C to harden the aluminum silicate to 15#n thickness x 150M width x 150
A porous body with a length of m was prepared. The porosity of this porous body was 91%.

Furthermore, the sound absorption coefficients for various frequencies were measured and the results are shown in FIG. 1, and it can be seen that a high sound absorption effect can be obtained at around 1000112.

Example-3 AJ-Mn alloy φ507111+1 round bar was cut with a lathe at ff11. After cutting the chips obtained by cutting with Osn to a length of about 1.0 m, the chips were mixed with aluminum phosphate as an inorganic binder and subjected to a load of 1.0 m. After loading O tons, heat it to 200°C to harden the aluminum phosphate and make it 15m thick x 20
A porous body with Os width x 200 m length was created. The porosity of this porous body was 66%.

Furthermore, the sound absorption coefficients for various frequencies were measured and the results are shown in FIG. 2, and it can be seen that a high sound absorption effect can be obtained at a frequency of 500 Hz.

(Effects of the Invention) As described above, according to the present invention, by using an inorganic binder and using aluminum or its alloy, a lightweight product with excellent heat resistance, weather resistance, breathability, sound absorption effect, etc. This has industrially significant effects such as the ability to obtain porous bodies.

[Brief explanation of the drawing]

Both FIG. 1 and FIG. 2 are actual measurement diagrams showing the sound absorption characteristics of the porous body of the present invention. 1HiΔArtificial]RoL1 Rate (%) Now! x41 chewing rate (%)

Claims (1)

[Claims] 1. A porous aluminum or aluminum alloy body, characterized in that powdered or fibrous aluminum or aluminum alloy mixed with an inorganic binder is compressed to 90% or less and then hardened to have a porosity of 30 to 96%.