JPH01319643A - Heat-resistant aluminum alloy material and its manufacture - Google Patents

Abstract

PURPOSE:To easily obtain the subject alloy material by forming the molten metal of an Al alloy having the compsn. in which the content of Fe, Ce, etc., is specified into powder by a gas atomizing method, subjecting it to compacting and limiting the size of an iron-contg. intermetallic compound. CONSTITUTION:An alloy contg., by weight, 5.0-15% Fe, 0.5-5% Ce and one or more kinds among 0.5-15% Co, 0.7-15% Cr, 0.3-10% Zr and 0.5-10% Ti, in which the total amt. of the elements to be added is regulated to <=25% and the balance Al with inevitable impurities is refined. The molten metal is subjected to rapid solidification by a gas atomizing method to form powder. The powder is subjected to hot compacting to manufacture an Al alloy material in which the average size of an Fe-contg. intermetallic compound is regulated to 0.07-1mum. If required, either about 0.5-15% Mn or about 0.2-10% Cu is furthermore added to the above compsn. By this method, the Al alloy material having excellent heat resistance can easily be mass-manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Use) The present invention relates to an aluminum alloy material with excellent heat resistance and a method for producing the same using a powder metallurgy method.

(Prior Art) Materials for automobile engine parts, gas turbine impellers, aircraft parts, etc. are required to have high-temperature strength at 100 to 400°C. If these phase materials are aluminum alloys, many advantages associated with weight reduction can be obtained. However, aluminum and its alloys are generally 1+'7; IHn
Intensity or low. For example, even in aluminum alloys (such as AA2018.2218.4032) that have excellent strength at room temperature, the strength decreases significantly at temperatures above 200°C.

In contrast, in recent years, aluminum powder metallurgy has been developed, in which a heat-resistant aluminum alloy is produced by high-temperature compression processing of a powder or ribbon-like thin strip obtained by adding large amounts of various transition elements to aluminum and rapidly solidifying the molten metal. Developed, Al-
8Fe-4Ce, Father A-8Fe-2M0. Al-8Fe
-2Go and other alloys are available.

Manufacturing process using powder metallurgy for aluminum alloys (J rapid solidification method: Aimize method, twin roll method, N is a spray roll method, etc.) to rapidly solidify the molten alloy into powder, liphon, or flake form. This is then cold formed into a green compact with a density ratio (ratio to true density) of 70% or more, sealed in a can, vacuum degassed, and then hot worked to a density ratio of 1.
A commonly used method is to form a 00% fillet h and further form it by extrusion, forging, etc. in order to increase the bonding force between the particles.

(Invention or problem to be solved) However, from-1-A, Q-8Fe-4Ce, An-
Alloys such as 8Fe-2Mo and Al-8Fe-2Go are
It is an alloy that exhibits excellent heat resistance by compacting the molten metal by ultra-rapidly solidifying it at 105°C/sec or higher and then compressing it. Speed 10~105°C/5ec)
Another problem was that sufficient strength and heat resistance could not be obtained.

On the other hand, there are ultra-rapid solidification methods that can achieve cooling rates of 105°C/sec or higher, such as the rapid-cooling roll method and the Mel-Svininck method, all of which require special manufacturing equipment and solidification technology. Therefore, it brings about 1 to 2 rises in cost. In general, the ultra-rapidly solidified material produced by the quench roll method is in the form of ribbons or flakes, and as it is, it is not suitable for compression molding, so it is necessary to cut it into small pieces. Therefore, there was a problem that the varnish was 1 to high.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a heat-resistant aluminum alloy that can be produced easily and inexpensively by compression molding a gas-amized powder, and a method for producing the same.

(Means for solving the problem) The inventors of the present invention conducted intensive research to solve the problem described in item 1 above by forming cusp 1 hemais powder using a molten metal of a specific aluminum alloy composition. The inventors discovered that the objective could be achieved, and based on this knowledge, they completed the present invention.

That is, the present invention includes (1) 5.0 to 15% by weight of Fe (hereinafter simply referred to as %), 0.5 to 5% of Ce, and 0.5 to 15% of Co.
15%, Cr 0.7-15%, Zr 0.3-1.0
% and 0.5 to 10% of Ti, the total amount of added elements is 25% or less, the balance is An and unavoidable impurities, and the average size of an intermetallic compound containing Fe. (2) F e 5. O
~15%, 0.5~5% of Ce, and 0.5% of Co.
5-15%, Cr0.7-15%, Zr0.3-10%
and 0.5 to 10% of Ti, and further contains any one of 0.5 to 15% of Mn and 82 to 10% of CuO, with the total amount of added elements being 25% or less and the remainder A, with an unavoidable lower purity, F
A heat-resistant aluminum alloy material characterized in that the average size of intermetallic compounds containing e is 007 to igm, (3) containing 5.0 to 15% of Fe, 0.5 to 5% of Ce, and 0.5-15%, Cr 0.7-
15%, one or more of Zr0.3-10% and Ti0.5-10%, and the total amount of added elements is 25%
Al with the remainder Al and unavoidable impurities
The molten alloy is rapidly solidified by gas atomization to form a powder, which is then hot compression molded. .07% 1pLm manufacturing method of heat-resistant aluminum alloy material and (4) Fe 5.0-15%, Ce 0.5-5
%, and Co 0.5-15%, Cr 0.7
~15%, Zr0.3-10% and Ti0.5-10%
Contains one or more of the following, and further includes Mn0.5 to 1
A molten Al alloy containing any one of 5% and 02 to 10% CuO, the total amount of added elements is 25% or less, and the balance is An and unavoidable impurities is rapidly solidified by gas atomization to produce a powder. The average size of the intermetallic compound containing Fe and having the above-mentioned composition is formed by hot compression molding.
The present invention provides a method for manufacturing a heat-resistant aluminum alloy material having a thickness of 1 μm.

The action of each component in the aluminum alloy material according to the present invention and the reason for limiting its content are as follows.

Fe content shall be 5.0-15%. Fe is finely dispersed as an intermetallic compound containing Fe during rapid solidification by gas atomization, and has the effect of increasing high-temperature strength. This effect is not sufficient when the Fe content is less than 5.0%, and when the Fe content exceeds 15%, not only does the degree of this effect become saturated, but the intermetallic compound becomes coarse.

The Ce content is set to 0.5 to 5%. Ce has the effect of refining the intermetallic compound containing Fe and the effect of increasing the thermal stability of the compound, and these effects increase the high-temperature strength. These effects are not sufficient when the Ce content is less than 0.5%, and on the other hand, when it exceeds 5%, the effects become saturated, resulting in a cost of 1 to 121.

Co, Cr, Zr, and Ti are each Co0.5 to 15
%, Cr 0.7 to 15%, Zr0j~]-0% and Ti 0.5 to 10%. One or more of them are added in combination. Like Ce, Co, Cr, Zr, and Ti have the effect of thermally stabilizing the intermetallic compound containing Fe, and this effect increases the high-temperature strength. Moreover, Mn 0.5-1
5% and any one of Cu 0.1 to 1.0% is added. Mn and Cu have two functions: one is to improve the strength by solid solution in Al, and the other is to improve the strength by finely precipitating in the lower part. If the amount of each element added is less than the lower limit, the effect will not be sufficient, and even if the amount exceeds the level of effect, the effect will not be saturated, leading to an increase in cost.

Further, the total amount of all additive elements is 25% or less. If the total amount exceeds 25%, the effect not only becomes saturated, but also increases the cost.

Further, even if 0.5 to 500 ppm of unavoidable impurities such as Be, B, Na, and Ca are contained in Al, the characteristics are not affected in any way.

Next, in the present invention, the average size of the intermetallic compound containing Fe in the aluminum alloy having the above composition is 0.07%.
1 lm.

In producing the aluminum alloy material of the present invention, a molten aluminum alloy having the above composition is rapidly solidified by gas atomization at a cooling rate of preferably 10 to 105° C.7 sec to form a powder, which is then hot compressed. Shape and process. Gas atomization method is used for paint, rocket 1-
This method has been widely used as a method for producing pure An powder for solid fuel, and by using the production equipment, it is possible to easily produce a large amount of alloy powder. Therefore, the manufacturing technology is well established, and the use of the customization method in mass production plans 1 to 1 has great benefits for varnish surfaces. In addition, since the rapidly solidified material produced by the cast atomization method is a particulate powder, it is also possible to
Compared to flake shapes, it has the advantage of being easier to handle and compression mold, and is advantageous in terms of manufacturing costs.

However, with the cast atomization method, it is currently difficult to reduce the size of the Fe-containing intermetallic compound that is finely dispersed during rapid solidification to less than 0.07 gm.

The powder below has a size of 0.0.
However, the proportion of powder of 5 gm or less in the powder produced by the Gasa 1 Hemeis method is low at about 2 to 3%, and it is extremely costly to classify and use only that.)
bring about a rise in Therefore, in this case, it is virtually impossible to reduce the size of the intermetallic compound containing Fe to less than 0.07 pLm. However, the average size of the Fe-containing intermetallic compound in a molded material obtained by compressing Kasua 1 Hemais powder is usually 0.07 to 1 μm. If the size of the intermetallic compound containing Fe is in the range of 0.07 to 1 m, sufficient heat resistance will be exhibited.

Next, it is preferable that the hot compression molding of the powder itself be carried out according to a conventional method, or that the temperature be 4006C or less. From the viewpoint of moldability, the higher the processing temperature, the better. However, although the addition of Ce, Co, Cr, Zr, and Ti thermally stabilizes intermetallic compounds containing Fe and prevents them from becoming coarse, processing temperatures exceeding 400°C cause intermetallic compounds to become coarse. The strength and heat resistance may deteriorate.

Further, it is preferable that the molded phase processed at high temperature is rapidly cooled by water quenching or the like immediately after processing. This increases the solid solution amount of Mn or Cu to determine whether the strength is further improved.

(Example) Next, the present invention will be explained in more detail based on examples.

Example Aluminum alloy (No. 1) having the composition shown in Table 1
~No., 20) were each made into a molten metal by a conventional method, and from this molten metal, an average particle size of 70 g was obtained by an Ar caster 1~mize method.
m powder was produced. The cooling rate in this atomization was 10 to 104°C/sec.

Next, each of the obtained alloy powders was cold preformed (compressed to a compression ratio of 80%, diameter 100 mm, length 1
20mm) - + aluminum can enclosure → high temperature vacuum degassing (
300°C) → Hot press forming (true density) → External cutting/
Through the decanning process, a fillet with a diameter of 80 mm and a length of 150 mm was produced, and this was extruded at 300°C to obtain an extruded material with a diameter of 30 mm.

For each alloy extruded material obtained as described above, a tensile test was performed at room temperature and 300°C (holding time 100 hr), and the average size of the intermetallic compound containing Fe was measured. The results are shown in Table 2.

Note that the average size of the intermetallic compound containing Fe was determined as follows. That is, the structure of each extruded material is observed using a transmission electron microscope, and the size of the compound is measured from a photograph of the structure using image analysis. Large number (1000 or more)
About the compound of l! In determination is performed and the sizes are averaged to determine the average size of the compound.

As is clear from the results in Table 2, the aluminum alloys (No. 1 to No. 17) produced by the method of the present invention were compared to the comparative examples (No. 1.8 to N.
o, 20), it is superior in both strength at room temperature and after being held at high temperatures.

(Effects of the Invention) The present invention is suitable for manufacturing engine parts, turbine impellers, aircraft parts, etc. that require heat-resistant strength (high temperature strength) by using a gas aluminization method without using an ultra-rapid solidification method. It is possible to obtain a heat-resistant aluminum alloy.

Moreover, the rapidly solidified aluminum alloy phase according to the present invention is not only easy to manufacture, but also can be obtained as an atomized powder and used as it is for compression molding. It has excellent effects.

Claims (4)

[Claims] (1) Contains 5.0 to 15% Fe, 0.5 to 5% Ce,
and Co0.5-15%, Cr0.7-15%, Zr
Contains one or more of 0.3 to 10% Ti and 0.5 to 10% Ti, and the total amount of added elements is 25% or less (or more,
% indicates weight %. ), the balance is Al and unavoidable impurities, and the average size of the Fe-containing intermetallic compound is 0.07 to 1 μm. (2) Contains Fe5.0-15%, Ce0.5-5%,
and Co0.5-15%, Cr0.7-15%, Zr
Contains one or more of 0.3-10% and Ti0.5-10%, and further contains Mn0.5-15% and Cu0.
．． A metal containing any one of 2 to 10%, the total amount of added elements is 25% or less (herein, % indicates weight %), the balance is Al and unavoidable impurities, and contains Fe. A heat-resistant aluminum alloy material characterized in that the average size of interstitial compounds is 0.07 to 1 μm. (3) Contains Fe5.0-15%, Ce0.5-5%,
and Co0.5-15%, Cr0.7-15%, Zr
Contains one or more of 0.3 to 10% Ti and 0.5 to 10% Ti, and the total amount of added elements is 25% or less (or more,
% indicates weight %. ) having the above-mentioned composition, which is characterized in that a molten Al alloy having the remainder Al and unavoidable impurities is rapidly solidified by gas atomization to form a powder, which is then hot compression molded. , and Fe
A method for producing a heat-resistant aluminum alloy material in which the average size of intermetallic compounds containing is 0.07 to 1 μm. (4) Contains Fe5.0-15%, Ce0.5-5%,
and Co0.5-15%, Cr0.7-15%, Zr
Contains one or more of 0.3-10% and Ti0.5-10%, and further contains Mn0.5-15% and Cu0.
．． A molten Al alloy containing any one of 2 to 10%, the total amount of added elements is 25% or less (herein, % indicates weight %), and the balance is Al and unavoidable impurities.
A powder having the above composition characterized in that it is rapidly solidified by gas atomization to form a powder and then hot compression molded, and the average size of the intermetallic compound containing Fe is 0.07 to 1 μm A method of manufacturing a certain heat-resistant aluminum alloy material.