JP2019183191A - Aluminum alloy powder and manufacturing method therefor, aluminum alloy extrusion material and manufacturing method therefor - Google Patents

Abstract

To provide an aluminum alloy extrusion material excellent in mechanical property at high temperature.SOLUTION: There is provided an aluminum alloy extrusion material containing Fe:5.0 mass% to 9.0 mass%, V:0.1 mass% to 3.0 mass%, Mo:0.1 mass% to 3.0 mass%, Zr:0.1 mass% to 2.0 mass%, Ti:0.02 mass% to 2.0 mass%, and one or two kind of metal selected from a group consisting of Cr and Mn of 0.02 mass% to 2.0 mass% respectively, and the balance Al with inevitable impurities, containing an Al-Fe-based intermetallic compound in the aluminum alloy extrusion material and having a structure with average circle equivalent diameter of the Al-Fe-based intermetallic compound in a cross section organization structure of the aluminum alloy extrusion material in a range of 0.1 μm to 3.0 μm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an aluminum alloy powder excellent in mechanical properties at high temperatures and a production method thereof, an aluminum alloy extruded material (extruded product) excellent in mechanical properties at high temperatures, and a production method thereof.

  A compressor impeller such as a compressor wheel in a turbocharger as an internal combustion engine of an automobile is provided with high strength and high rigidity at a high temperature exceeding 10,000 rpm under a high temperature condition of about 150 ° C. Required. In addition, the compressor impeller is required to be lightweight in order to reduce energy loss, and to be strong enough to withstand high-speed rotation.

  For example, conventionally, a compressor impeller is made of a 2618 alloy (Cu: 1.9 mass% to 2.7 mass%, Mg: 1.3 mass% to 1.8 mass%, Ni: 0.9 mass% to 1. mass%). 2 mass%, Fe: 0.9 mass% to 1.3 mass%, Si: 0.1 mass% to 0.25 mass%, Ti: 0.04 mass% to 0.1 mass%, the balance Was manufactured by cutting a cast / forged product made of Al).

  However, due to the recent increase in cutting speed, the aluminum alloy extruded material has been made into a cut product, and further improvements in machinability and high temperature strength are required.

  For example, Patent Document 1 discloses a technique for providing an Al—Cu—Mg-based aluminum alloy extruded material whose strength at a high temperature (160 ° C.) is improved as compared with the prior art. That is, in Patent Document 1, Cu: 3.4 to 5.5% (mass%, the same applies hereinafter), Mg: 1.7 to 2.3%, Ni: 1.0 to 2.5%, Fe: 0.5-1.5%, Mn: 0.1-0.4%, Zr: 0.05-0.3%, Si: less than 0.1%, Ti: less than 0.1%, the balance A heat-resistant aluminum alloy extruded material excellent in high-temperature strength and high-temperature fatigue characteristics characterized by comprising Al and inevitable impurities is described.

Japanese Patent No. 5284935

  By the way, in the technical field of internal combustion engines such as automobiles, compressor impellers and the like are required to be further rotated at high speed. Therefore, as an aluminum alloy material as a constituent material of compressor impellers and the like, even in a higher temperature range than before. What has excellent mechanical properties is desired. Moreover, as a characteristic requested | required of these members, it is requested | required that dynamic strengths, such as a creep characteristic other than static strength, are excellent.

  The present invention has been made in view of such a technical background, and provides an aluminum alloy powder excellent in mechanical properties at high temperatures and a manufacturing method thereof, an aluminum alloy extruded material excellent in mechanical properties at high temperatures, and a manufacturing method thereof. The purpose is to do.

  In order to achieve the above object, the present invention provides the following means.

[1] Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass, Zr: 0.1 1% or 2 types of metals selected from the group consisting of Cr and Mn, each containing 0.02% by mass, containing 0.02% by mass to 2.0% by mass, Ti: 0.02% by mass, -2.0 mass% aluminum alloy powder containing the balance and Al and inevitable impurities,
The aluminum alloy powder contains an Al—Fe based intermetallic compound, and the average equivalent circle diameter of the Al—Fe based intermetallic compound is in the range of 0.1 μm to 3.0 μm in the cross-sectional structure of the aluminum alloy powder. An aluminum alloy powder characterized by being.

  [2] The aluminum alloy powder according to item 1, wherein the aluminum alloy further contains 0.0001% by mass to 0.03% by mass of B.

  [3] Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass, Zr: 0.1 1% or 2 types of metals selected from the group consisting of Cr and Mn, each containing 0.02% by mass, containing 0.02% by mass to 2.0% by mass, Ti: 0.02% by mass, A method for producing an aluminum alloy powder, characterized in that an aluminum alloy powder is obtained by quenching and solidifying a molten aluminum alloy containing ~ 2.0% by mass, the balance being Al and inevitable impurities, by an atomizing method.

[4] Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass, Zr: 0.1 1% or 2 types of metals selected from the group consisting of Cr and Mn, each containing 0.02% by mass, containing 0.02% by mass to 2.0% by mass, Ti: 0.02% by mass, It is an aluminum alloy extruded material containing ~ 2.0% by mass, the balance being Al and inevitable impurities,
The aluminum alloy extrudate contains an Al—Fe intermetallic compound, and the average equivalent circle diameter of the Al—Fe intermetallic compound is 0.1 μm to 3.0 μm in the cross-sectional structure of the aluminum alloy extrudate. An aluminum alloy extruded material characterized by being in a range.

  [5] The aluminum alloy extruded material according to item 4, wherein the aluminum alloy extrusion further contains 0.0001% by mass to 0.03% by mass of B.

[6] The intermetallic compound is an Al—Fe—V—Mo intermetallic compound containing at least Al, Fe, V, and Mo,
In the intermetallic compound, the Al content is 81.60 mass% to 92.37 mass%, the Fe content is 2.58 mass% to 10.05 mass%, and the V content is 1.44 mass%. The aluminum alloy extruded material according to claim 4 or 5, which has ˜4.39 mass% and a Mo content of 2.45 mass% to 3.62 mass%.

[7] A compression molding step for obtaining a green compact by compression molding the aluminum alloy powder according to the item 1 or 2,
An extrusion step of hot extruding the green compact to obtain an extruded material,
The extrudate contains an Al—Fe intermetallic compound in the extrudate, and an average equivalent circle diameter of the Al—Fe intermetallic compound in the cross-sectional structure of the extrudate is 0.1 μm to 3.0 μm. The manufacturing method of the aluminum alloy extruded material characterized by the above-mentioned.

  According to the invention of [1], an aluminum alloy powder excellent in mechanical properties at a high temperature is provided. Therefore, by using this aluminum alloy powder, an aluminum alloy extruded material (extruded product) excellent in mechanical properties (static strength, creep properties, etc.) at high temperatures can be produced.

  According to the invention of [2], an aluminum alloy powder with improved mechanical properties (value) at high temperatures is provided.

  According to the invention of [3], since the molten aluminum alloy is rapidly solidified by atomization and powdered, the diffusion of each element of the alloy during solidification is suppressed, and the coarsening of crystal grains and precipitates is suppressed. In addition, the appearance of equilibrium and metastable phases can be further suppressed, the solid solution amount of the transition element Fe can be increased, and the aluminum has excellent mechanical properties (static strength, creep properties, etc.) at high temperatures. Alloy powder can be produced. Therefore, by using this aluminum alloy powder, an aluminum alloy extruded material (extruded product) excellent in mechanical properties at high temperatures can be produced.

  According to the invention of [4], an aluminum alloy extruded material (extruded product) excellent in mechanical properties (static strength, creep properties, etc.) at a high temperature is provided. This aluminum alloy extruded material is suitable as an internal combustion engine member such as a turbo compressor impeller of a turbocharger for automobiles. In other words, this aluminum alloy extruded material is suitable, for example, as an internal combustion engine member (internal combustion engine component) that rotates at high speed under high temperature.

  According to the invention of [5], an aluminum alloy extruded material with improved mechanical properties (value) at high temperature is provided.

  According to the invention of [6], an aluminum alloy extruded material further improved in mechanical properties (value) at a high temperature is provided.

  According to the invention of [7], an aluminum alloy extruded material (extruded product) excellent in mechanical properties (static strength, creep properties, etc.) at high temperatures can be produced. The obtained aluminum alloy extruded material is suitable as an internal combustion engine member such as a turbo compressor impeller of a turbocharger for automobiles. In other words, the obtained aluminum alloy extruded material is suitable, for example, as an internal combustion engine member (internal combustion engine component) that rotates at high speed under high temperature.

It is a perspective view which shows an example of the aluminum alloy extrusion material (extruded product) of this invention.

  The aluminum alloy powder according to the present invention includes Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass. , Zr: 0.1% by mass to 2.0% by mass, Ti: 0.02% by mass to 2.0% by mass, and one or two metals selected from the group consisting of Cr and Mn, Each aluminum alloy powder containing 0.02% by mass to 2.0% by mass with the balance being Al and inevitable impurities, the aluminum alloy powder containing an Al—Fe intermetallic compound, and the aluminum alloy In the cross-sectional structure of the powder, the average equivalent circle diameter of the Al—Fe intermetallic compound is in the range of 0.1 μm to 3.0 μm. With such a configuration, an aluminum alloy powder excellent in mechanical properties at high temperatures is provided. Therefore, by using the aluminum alloy powder of the present invention, an aluminum alloy extruded material (extruded product) excellent in mechanical properties (static strength, creep properties, etc.) at high temperatures can be produced.

  The average particle diameter of the aluminum alloy powder is not particularly limited, but is preferably in the range of 30 μm to 70 μm. When the thickness is 30 μm or more, the yield of manufacturing the alloy powder can be remarkably improved, and when the thickness is 70 μm or less, mixing of coarse oxides and foreign matters can be avoided.

  Next, the manufacturing method of the aluminum alloy powder based on this invention is demonstrated. In this production method, Fe: 5.0 mass% to 9.0 mass%, V: 0.1 mass% to 3.0 mass%, Mo: 0.1 mass% to 3.0 mass%, Zr: 0 0.1% by mass to 2.0% by mass, Ti: 0.02% by mass to 2.0% by mass, and one or two metals selected from the group consisting of Cr and Mn are each 0.02%. Aluminum alloy powder (aluminum alloy atomized powder) is obtained by rapidly solidifying a molten aluminum alloy containing mass% to 2.0 mass%, the balance being Al and unavoidable impurities by an atomizing method (powdering step). . By such a manufacturing method, an aluminum alloy powder having the above-described configuration can be provided, that is, by the above manufacturing method, an aluminum alloy powder having the above specific composition, and an Al—Fe-based intermetallic compound in the aluminum alloy powder. In which the average equivalent circle diameter of the Al—Fe intermetallic compound is in the range of 0.1 μm to 3.0 μm in the cross-sectional structure of the aluminum alloy powder.

In the powdering step, the molten aluminum alloy having the specific composition is prepared by a normal melting method. The obtained molten aluminum alloy is pulverized by an atomizing method. The atomization method is a method in which fine droplets of molten aluminum alloy are atomized and sprayed by a gas flow such as nitrogen gas from a spray nozzle, and the fine droplets are rapidly solidified to obtain a fine aluminum alloy powder. The cooling rate is preferably 10 ² to 10 ⁵ ° C / second. It is preferable to obtain an aluminum alloy powder having an average particle size of 30 μm to 70 μm. The obtained aluminum alloy powder is preferably classified using a sieve.

  The aluminum alloy powder according to the present invention (the invention of [1]) is not limited to the aluminum alloy powder obtained by the above production method, but also includes those obtained by other production methods.

Next, the manufacturing method of the aluminum alloy extrusion material which concerns on this invention is demonstrated. The aluminum alloy powder obtained in the powdering step is compression molded to obtain a green compact (compression molding step). For example, an aluminum alloy powder heated to 250 ° C. to 300 ° C. is filled in a mold heated to 230 ° C. to 270 ° C., and compression molded into a predetermined shape to obtain a green compact. The pressure for the compression molding is not particularly limited, but usually it is preferably set to 0.5 ton / cm ^{2 to} 3.0 ton / cm ² . Moreover, it is preferable to use a green compact with a relative density of 60% to 90%. The shape of the green compact is not particularly limited, but it is preferably a cylindrical shape or a disk shape in consideration of the next extrusion process.

  Next, the green compact obtained in the compression molding step is hot-extruded to obtain an extruded material (extrusion step). The green compact is subjected to machining such as chamfering as necessary, and then subjected to degassing treatment and heated to be subjected to an extrusion process. The heating temperature of the green compact before extrusion is preferably 300 ° C to 450 ° C. At the time of extrusion, for example, the green compact is inserted into an extrusion container, pressure is applied by an extrusion ram, and the extrusion die is extruded into, for example, a round bar shape. At this time, it is desirable to heat the extrusion container to 300 ° C. to 400 ° C. in advance. By extruding in this way, plastic deformation of the green compact proceeds, and an extruded body in which aluminum alloy powders (particles) are combined and integrated is obtained. During the extrusion, the extrusion pressure is preferably set to 10 MPa to 25 MPa.

  The extruded material 1 obtained in the extrusion process contains an Al—Fe-based intermetallic compound in the extruded material, and the average equivalent circle diameter of the Al—Fe-based intermetallic compound in the cross-sectional structure of the extruded material is It is the structure which exists in the range of 0.1 micrometer-5.0 micrometers. Thus, the aluminum alloy extruded material of the present invention can be obtained.

  The aluminum alloy extruded material (aluminum alloy extruded material according to the present invention) obtained by the method for producing an aluminum alloy extruded material according to the present invention described above is Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass, Zr: 0.1% by mass to 2.0% by mass, Ti: 0.02% by mass to 2.% by mass. Aluminum alloy containing 0% by mass, one or two metals selected from the group consisting of Cr and Mn, each containing 0.02% by mass to 2.0% by mass, with the balance being Al and inevitable impurities The aluminum alloy extrudate contains an Al—Fe intermetallic compound, and the average equivalent circle diameter of the Al—Fe intermetallic compound is 0. 0 in the cross-sectional structure of the aluminum alloy extrudate. Range of 1 μm to 3.0 μm It is the composition which is.

  In addition, the aluminum alloy extrusion material which concerns on this invention is not limited to the aluminum alloy extrusion material obtained by the said manufacturing method, The thing obtained by the other manufacturing method is also included.

  Next, the composition of “aluminum alloy” in the above-described aluminum alloy powder, aluminum alloy powder manufacturing method, aluminum alloy extruded material, and aluminum alloy extruded material manufacturing method according to the present invention will be described in detail below. The aluminum alloy contains Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass, Zr: 0. 0.1% by mass to 2.0% by mass, Ti: 0.02% by mass to 2.0% by mass, and one or two metals selected from the group consisting of Cr and Mn are each 0.02%. It is an aluminum alloy containing from mass% to 2.0 mass%, with the balance being Al and inevitable impurities.

  The Fe (component) is an element that generates an Al—Fe-based intermetallic compound having a high melting point and can improve mechanical properties (static strength, creep properties, etc.) in a high temperature range of, for example, 200 ° C. to 350 ° C. is there. The Fe content in the aluminum alloy is in the range of 5.0 mass% to 9.0 mass%. When the Fe content is less than 5.0% by mass, the strength of the product such as an aluminum alloy extruded material is reduced. When the Fe content exceeds 9.0% by mass, the ductility of the product such as the aluminum alloy extruded material is reduced. It cannot decrease and cannot obtain a product having excellent mechanical properties (static strength, creep properties, etc.) at a high temperature of a product such as an aluminum alloy extruded material. Especially, it is preferable that the Fe content rate in the said aluminum alloy is the range of 7.0 mass%-8.0 mass%.

  Said V (component) is an element which produces | generates an Al-Fe-V-Mo type | system | group intermetallic compound, and can improve the mechanical characteristics (static strength, creep characteristics, etc.) in the high temperature range of 200 to 350 degreeC, for example. is there. V content rate in the said aluminum alloy shall be the range of 0.1 mass%-3.0 mass%. When the V content is less than 0.1% by mass, the strength of the product such as an aluminum alloy extruded material is reduced. When the V content exceeds 3.0% by mass, the ductility of the product such as the aluminum alloy extruded material is reduced. It cannot decrease and cannot obtain a product having excellent mechanical properties (static strength, creep properties, etc.) at a high temperature of a product such as an aluminum alloy extruded material. Especially, it is preferable that the V content rate in the said aluminum alloy is the range of 1.0 mass%-2.0 mass%.

  The Mo (component) is an element that generates an Al-Fe-V-Mo intermetallic compound and can improve mechanical properties (static strength, creep properties, etc.) in a high temperature range of, for example, 200 ° C to 350 ° C. is there. Mo content rate in the said aluminum alloy shall be the range of 0.1 mass%-3.0 mass%. When the Mo content is less than 0.1% by mass, the strength of the product such as an aluminum alloy extruded material is reduced. When the Mo content exceeds 3.0% by mass, the ductility of the product such as the aluminum alloy extruded material is reduced. It cannot decrease and cannot obtain a product having excellent mechanical properties (static strength, creep properties, etc.) at a high temperature of a product such as an aluminum alloy extruded material. Especially, it is preferable that the Mo content rate in the said aluminum alloy is the range of 1.0 mass%-2.0 mass%.

  The Zr (component) is an element that does not cause coarsening of the Al—Fe—V—Mo intermetallic compound and can realize fine crystallization of the intermetallic compound. Further, by containing Zr, the high temperature strength can be improved, and the self-diffusion of Al in the Al matrix can be suppressed and the creep characteristics can be improved. The Zr content in the aluminum alloy is in the range of 0.1% by mass to 2.0% by mass. When the Zr content is less than 0.1% by mass, there arises a problem that the effects of precipitation strengthening and dispersion strengthening cannot be exhibited. On the other hand, when the Zr content exceeds 2.0% by mass, a coarse intermetallic compound containing Zr is generated (see Comparative Example 9 described later), so that good mechanical properties cannot be obtained. Especially, it is preferable that the Zr content rate in the said aluminum alloy is the range of 0.5 mass%-1.5 mass%.

The Ti (component) has a role of forming an Al— (Ti, Zr) -based intermetallic compound having an L ₁₂ structure with Al in cooperation with the Zr. Moreover, since Ti has a small diffusion coefficient in the Al matrix, the effect of improving the creep characteristics can be obtained. Ti content rate in the said aluminum alloy shall be 0.02 mass%-2.0 mass%. When the Ti content is less than 0.02% by mass, there arises a problem that the effects of precipitation strengthening and dispersion strengthening cannot be exhibited. On the other hand, when the Ti content exceeds 2.0% by mass, ductility is lowered, and an aluminum alloy powder and an aluminum alloy extruded material excellent in mechanical properties (static strength, creep properties, etc.) at high temperatures cannot be obtained. Especially, it is preferable that Ti content rate in the said aluminum alloy is the range of 0.5 mass%-1.0 mass%.

  In the present invention, the aluminum alloy further contains one or two metals selected from the group consisting of Cr and Mn. That is, the aluminum alloy may have a composition further containing Cr: 0.02% by mass to 2.0% by mass, or may further contain Mn: 0.02% by mass to 2.0% by mass. The composition may also be a composition containing Cr: 0.02% by mass to 2.0% by mass and Mn: 0.02% by mass to 2.0% by mass. Cr (component) and Mn (component) are dissolved in the Al matrix and exert an effect as solid solution strengthening. However, when the extrusion temperature is 500 ° C. or higher, precipitation proceeds and the mechanical properties at high temperatures are likely to be lowered. Therefore, the extrusion temperature is preferably set to less than 500 ° C. Moreover, since the dispersed particles of Cr or / and Mn have the effect of suppressing the grain boundary movement after recrystallization, for example, the coarsening of the average crystal grain size in the ST direction of the parting line structure during the forging process can be suppressed. Further, fine crystal grains and sub-crystal grains can be obtained over the entire aluminum alloy extruded material and forged material of the present invention, and the mechanical characteristics can be further improved.

  Moreover, by containing Zr and Cr or / and Mn at the above-mentioned contents, respectively, it is possible to increase the 0.2% yield strength by solid solution in the Al matrix.

  By containing 0.02% by mass or more of Cr, Cr can be dissolved in the Al matrix and mechanical characteristics (particularly fatigue strength at high temperatures) can be improved, and wear resistance can be improved. The Cr can be dissolved in the Al matrix to improve the corrosion resistance, and the resistance to temper softening can be improved. Therefore, by adding Cr, the hardenability can be improved and the heat treatment hardness can be improved. . In addition, by setting the Cr content to 2.0 mass% or less, Cr can be dissolved in the Al matrix, and a coarse intermetallic compound containing Cr is produced, resulting in a decrease in mechanical properties. Can be prevented, a decrease in thermal conductivity can be avoided, and the temperature rise of the contact surface due to sliding can be prevented, thereby improving the scuffing resistance. Especially, when Cr is contained, it is more preferable to set the Cr content to 0.05 mass% to 1.5 mass%.

  Further, by containing 0.02% by mass or more of Mn, the effect that Mn can be dissolved in the Al matrix and the mechanical properties (particularly fatigue strength at high temperature) can be improved is obtained. It is done. In addition, when the Mn content is 2.0% by mass or less, Mn can be dissolved in the Al matrix, and a coarse intermetallic compound containing Mn is generated, resulting in a decrease in mechanical properties. Can be prevented. Especially, when Mn is contained, it is more preferable to set the Mn content to 0.05 mass% to 1.5 mass%.

  In this invention, the said aluminum alloy is good also as a structure (composition) which contains 0.0001 mass%-0.03 mass% of B (boron) further. By setting it as the composition which contained B by the said specific ratio, a crystal grain can be refined | miniaturized and a mechanical characteristic can be improved.

  In the present invention, the aluminum alloy powder or the aluminum alloy extrudate contains an Al-Fe intermetallic compound, and the Al-Fe intermetallics in the cross-sectional structure of the aluminum alloy powder or the aluminum alloy extrudate. The average equivalent circle diameter of the compound is in the range of 0.1 μm to 3.0 μm. When the average equivalent circle diameter of the intermetallic compound is less than 0.1 μm, the effect of dispersion strengthening cannot be exhibited. In addition, when the average equivalent circle diameter of the intermetallic compound exceeds 3.0 μm, a coarse intermetallic compound is formed, and since it breaks from the starting point, the mechanical property is deteriorated. Among these, in the cross-sectional structure of the aluminum alloy powder or the aluminum alloy extruded material, the average equivalent circle diameter of the Al—Fe intermetallic compound is preferably in the range of 0.3 μm to 2.0 μm, and more preferably 0.4 μm. A range of ˜1.5 μm is particularly preferred.

  The Al—Fe-based intermetallic compound is not particularly limited, and examples thereof include an Al—Fe—V—Mo-based intermetallic compound containing at least Al, Fe, V, and Mo. . In the Al—Fe—V—Mo intermetallic compound, the Al content is 81.60 mass% to 92.37 mass%, the Fe content is 2.58 mass% to 10.05 mass%, The content ratio is preferably 1.44% by mass to 4.39% by mass, and the Mo content is preferably 2.45% by mass to 3.62% by mass. In this case, the composition is good in a high temperature range of 200 ° C. or higher. Mechanical properties can be obtained.

  The equivalent circle diameter of the Al-Fe intermetallic compound has the same area as the area of the Al-Fe intermetallic compound in the SEM photograph (image) of the cross section of the aluminum alloy powder or the extruded aluminum alloy material. It is a value converted as the diameter of a circle.

  Next, specific examples of the present invention will be described, but the present invention is not particularly limited to these examples.

<Example 1>
Fe: 8.0 mass%, V: 2.0 mass%, Mo: 2.0 mass%, Zr: 1.0 mass%, Ti: 1.0 mass%, Cr: 0.1 mass%, Al: After heating an aluminum alloy containing 85.9% by mass and containing inevitable impurities to obtain a molten aluminum alloy at 1000 ° C., the molten aluminum alloy is atomized with a gas, rapidly solidified, and powdered. An aluminum alloy powder (aluminum alloy atomized powder) having an average particle diameter of 50 μm was obtained.

Next, the obtained aluminum alloy powder is preheated to a temperature of 280 ° C., the preheated aluminum alloy powder is filled in a mold heated and held at the same 280 ° C., and the pressure is 1.5 ton / cm ² . Compression molding was performed to obtain a cylindrical green compact (molded body) having a diameter of 210 mm and a length of 250 mm. Next, the obtained green compact was chamfered to a diameter of 203 mm with a lathe to obtain a green compact billet.

  Next, the obtained billet is heated to 400 ° C., and the heated billet is inserted into an extrusion container having an inner diameter of 210 mm heated and held at 400 ° C., and an extrusion ratio of 6.4 is obtained by an indirect extrusion method using a die having an inner diameter of 83 mm. Extruded material 1 was obtained by extrusion (see FIG. 1).

<Example 2>
As an aluminum alloy for forming a molten aluminum alloy, Fe: 8.0 mass%, V: 2.0 mass%, Mo: 2.0 mass%, Zr: 1.0 mass%, Ti: 1.0 mass Extruded material 1 was obtained in the same manner as in Example 1 except that an aluminum alloy containing 0.5% by mass, Cr: 0.5% by mass, and Al: 85.5% by mass and containing inevitable impurities was used.

<Examples 3 to 8>
Extruded material 1 was obtained in the same manner as in Example 1, except that an aluminum alloy having an alloy composition (containing unavoidable impurities) shown in Table 1 was used as the aluminum alloy for forming the molten aluminum alloy.

<Examples 9 to 16>
Extruded material 1 was obtained in the same manner as in Example 1 except that an aluminum alloy having an alloy composition (containing inevitable impurities) shown in Table 2 was used as the aluminum alloy for forming the molten aluminum alloy.

<Examples 17 and 18, Comparative Examples 1 to 6>
Extruded material 1 was obtained in the same manner as in Example 1 except that an aluminum alloy having an alloy composition (containing inevitable impurities) shown in Table 3 was used as the aluminum alloy for forming the molten aluminum alloy.

<Comparative Examples 7-14>
Extruded material 1 was obtained in the same manner as in Example 1 except that an aluminum alloy having an alloy composition shown in Table 4 (containing inevitable impurities) was used as the aluminum alloy for forming the molten aluminum alloy.

  Each aluminum alloy extruded material (extruded product) obtained as described above was evaluated based on the following evaluation method. The results are shown in Tables 1-4. In addition, in each element column in Tables 1 to 4, the notation “−” indicates that the value is less than the detection limit (0.005 mass%) (that is, the element was not detected).

In Tables 1 to 4, “average equivalent circle diameter (μm) of intermetallic compounds” is an Al—Fe—V—Mo intermetallic compound (Al, Fe, It is an average equivalent circular diameter (μm) of an intermetallic compound containing at least V and Mo. This “average circle equivalent diameter (μm) of intermetallic compound” is vertical from the center (intermediate bisection position) in the L direction (length direction, that is, axial direction) of the obtained aluminum alloy extruded material (cylindrical body). A sample piece for tissue observation having a size of 10 mm × width 10 mm × thickness 10 mm was cut out, this sample piece was micro-polished using a cross-section sample preparation device (Cross section polisher), and an SEM photograph of the sample piece after micro-polishing. (Scanning electron micrograph) was taken, and the average equivalent circle diameter (μm) of the intermetallic compound was determined (evaluated) from this photographic image. The average equivalent circle diameter was determined for 10 Al—Fe—V—Mo intermetallic compounds existing in the field of view of 1.5815 mm ² in the SEM photograph.

<Tensile strength evaluation method at high temperature>
The obtained aluminum alloy extruded material (cylindrical body) is processed into a tensile test piece having a distance between gauge points of 20 mm and a parallel part diameter of 4 mm, and a high temperature tensile test is performed on the tensile test piece (260 ° C.). Tensile strength) was measured. The high temperature tensile test was performed in a measurement environment at 260 ° C. after holding the high temperature tensile test piece at 260 ° C. for 100 hours. Evaluation was made based on the following criteria.
(Criteria)
“◎”: The tensile strength at 260 ° C. is 356 MPa or more “O”: The tensile strength at 260 ° C. is 351 MPa or more and 355 MPa or less “Δ” ... The tensile strength at 260 ° C. is 346 MPa or more and 350 MPa or less “X”: At 260 ° C. Has a tensile strength of 345 MPa or less.

<High-temperature fatigue test method>
The obtained aluminum alloy extruded material (cylindrical body) is processed into a fatigue test piece having a distance between the gauge points of 30 mm and a parallel part diameter of 8 mm, and the fatigue test piece is subjected to a high temperature fatigue test (260 ° C.). Fatigue strength) was measured. In the high temperature fatigue test, the fatigue test piece was held at 260 ° C. for 100 hours, and then the test was conducted 500,000 times under a measurement environment of 260 ° C. under a condition of a repetition rate of 3600 rpm. Evaluation was made based on the following criteria.
(Criteria)
“◎”: the fatigue strength at 260 ° C. is 226 MPa or more “O”: the fatigue strength at 260 ° C. is 221 MPa or more and 225 MPa or less “Δ”: the fatigue strength at 260 ° C. is 216 MPa or more and 220 MPa or less “×”: at 260 ° C. Has a fatigue strength of 215 MPa or less.

<Creep test method at high temperature>
The obtained aluminum alloy extruded material (cylindrical body) is processed into a creep test piece having a distance between gauge points of 30 mm and a parallel part diameter of 6 mm, and a high temperature creep test is performed on the creep test piece (260 ° C.). Creep characteristics) were measured. The high temperature creep test was conducted in a measurement environment at 260 ° C. after the creep test piece was held at 260 ° C. for 100 hours. The creep rupture strength was calculated under the conditions of temperature: 260 ° C. and rupture time of 300 hours, and evaluated based on the following criteria.
(Criteria)
“◎”: Creep rupture strength at 260 ° C. is 216 MPa or more “O” ... Creep rupture strength at 260 ° C. is 211 MPa or more and 215 MPa or less “Δ” ... Creep rupture strength at 260 ° C. is 206 MPa or more and 210 MPa or less “×” ... The creep rupture strength at 260 ° C. is 205 MPa or less.

  As is apparent from the table, the extruded aluminum alloy materials of Examples 1 to 18 according to the present invention were excellent in various mechanical properties at a high temperature (260 ° C.).

  On the other hand, the aluminum alloy extruded materials of Comparative Examples 1 to 14 deviating from the specified range of the present invention were inferior in mechanical properties at a high temperature (260 ° C.).

  The aluminum alloy material formed using the aluminum alloy powder according to the present invention and the aluminum alloy powder obtained by the production method of the present invention is excellent in mechanical properties at high temperatures. Moreover, since the aluminum alloy extruded material according to the present invention and the aluminum alloy extruded material obtained by the production method of the present invention are excellent in mechanical properties at high temperatures, a turbo compressor for a turbocharger used in an internal combustion engine such as an automobile. It is suitably used as an internal combustion engine member (internal combustion engine component) that rotates at high speed under high temperature, such as an impeller.

1 ... Aluminum alloy extruded material (extruded product)

Claims (7)

Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass, Zr: 0.1% by mass to 2.0% by mass, Ti: 0.02% by mass to 2.0% by mass, and one or two metals selected from the group consisting of Cr and Mn are each 0.02% by mass to 2.% by mass. An aluminum alloy powder containing 0% by mass, the balance being Al and inevitable impurities,
The aluminum alloy powder contains an Al—Fe based intermetallic compound, and the average equivalent circle diameter of the Al—Fe based intermetallic compound is in the range of 0.1 μm to 3.0 μm in the cross-sectional structure of the aluminum alloy powder. An aluminum alloy powder characterized by being.   The aluminum alloy powder according to claim 1, wherein the aluminum alloy further contains 0.0001 mass% to 0.03% by mass of B.   Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass, Zr: 0.1% by mass to 2.0% by mass, Ti: 0.02% by mass to 2.0% by mass, and one or two metals selected from the group consisting of Cr and Mn are each 0.02% by mass to 2.% by mass. A method for producing an aluminum alloy powder, characterized in that an aluminum alloy powder is obtained by rapidly solidifying a molten aluminum alloy containing 0% by mass and the balance consisting of Al and inevitable impurities by an atomizing method. Fe: 5.0% by mass to 9.0% by mass, V: 0.1% by mass to 3.0% by mass, Mo: 0.1% by mass to 3.0% by mass, Zr: 0.1% by mass to 2.0% by mass, Ti: 0.02% by mass to 2.0% by mass, and one or two metals selected from the group consisting of Cr and Mn are each 0.02% by mass to 2.% by mass. An aluminum alloy extruded material containing 0% by mass and the balance being Al and inevitable impurities,
The aluminum alloy extrudate contains an Al—Fe intermetallic compound, and the average equivalent circle diameter of the Al—Fe intermetallic compound is 0.1 μm to 3.0 μm in the cross-sectional structure of the aluminum alloy extrudate. An aluminum alloy extruded material characterized by being in a range.   The said aluminum alloy extrusion is an aluminum alloy extrusion material of Claim 4 which contains 0.0001 mass%-0.03 mass% of B further. The intermetallic compound is an Al-Fe-V-Mo intermetallic compound containing at least Al, Fe, V and Mo,
In the intermetallic compound, the Al content is 81.60 mass% to 92.37 mass%, the Fe content is 2.58 mass% to 10.05 mass%, and the V content is 1.44 mass%. The aluminum alloy extruded material according to claim 4 or 5, which has ˜4.39 mass% and a Mo content of 2.45 mass% to 3.62 mass%. A compression molding step for obtaining a green compact by compression molding the aluminum alloy powder according to claim 1 or 2,
An extrusion step of hot extruding the green compact to obtain an extruded material,
The extrudate contains an Al—Fe intermetallic compound in the extrudate, and an average equivalent circle diameter of the Al—Fe intermetallic compound in the cross-sectional structure of the extrudate is 0.1 μm to 3.0 μm. The manufacturing method of the aluminum alloy extruded material characterized by the above-mentioned.

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