Powder metal material for additive manufacturing made of aluminum alloy, and additive manufacturing method

Abstract

To provide a powder metal material for additive manufacturing that is composed of an aluminum alloy with a high laser absorption rate, and an additive manufacturing method using the powder metal material.SOLUTION: Provided is a powder metal material for additive manufacturing, which is composed of an aluminum alloy and has an absorption rate of 65% or more determined by the following regression equation: Absorption rate (%)=23.5+1.9[Si]+7.4[Fe]-4.0[Cu]+109.6[Mn]+45.1[Mg]-14.5[Zn]-14.2[Ti]+2.6[Ni]-3.0[Zr]-218.1[Sc], where, [ ] represents a content (mass%) of each element.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a powder metal material for laminated manufacturing made of an aluminum alloy and a laminated manufacturing method.

Background Art

[0002] Aluminum alloys are used, for example, in applications where weight reduction is required, such as vehicles and aircraft. A laminated manufacturing method using aluminum alloy powder is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Conventional aluminum alloy powders have mainly been developed for the purpose of improving the mechanical properties of objects formed by a laminated manufacturing method. However, conventional aluminum alloy powders such as Al10SiMg and AlMgSc have problems such as high laser reflectivity and slow forming speed. Also, from the perspective of energy efficiency, it is required to increase the laser absorption rate. The present invention provides a powder metal material for laminated manufacturing made of an aluminum alloy with a high laser absorption rate, and a laminated manufacturing method using the above powder metal material.

Means for Solving the Problems

[0005] The powder metal material of the present invention is a powder metal material for laminated manufacturing made of an aluminum alloy, and is a powder metal material having an absorption rate of 65% or more obtained by the following regression formula. Absorption rate (%)=23.5+1.9[Si]+7.4[Fe]-4.0[Cu]+109.6[Mn]+45.1[Mg]-14.5[Zn]-14.2[Ti]+2.6[Ni]-3.0[Zr]-218.1[Sc] In the above formula, [ ] indicates the content (mass%) of each element. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a powder metal material for additive manufacturing made of an aluminum alloy with a high laser absorption rate, and an additive manufacturing method using the above powder metal material. [Brief explanation of the drawing]

[0007] [Figure 1] This graph shows the relationship between measured and calculated values ​​of the absorption rate of aluminum alloy powder using a laser (wavelength 1081 nm). [Modes for carrying out the invention]

[0008] The embodiments for carrying out the present invention will be described in detail below.

[0009] [Powder metal materials] The powder metal material of the present invention is a powder metal material for additive manufacturing made of an aluminum alloy, wherein the absorption rate determined by the following regression equation is 65% or more. Absorption rate (%)=23.5+1.9[Si]+7.4[Fe]-4.0[Cu]+109.6[Mn]+45.1[Mg]-14.5[Zn]-14.2[Ti]+2.6[Ni]-3.0[Zr]-218.1[Sc] In the above formula, [ ] indicates the content (mass%) of each element. Specifically, [Si] indicates the Si content (mass%) in the powder metal material, [Fe] indicates the Fe content (mass%) in the powder metal material, [Cu] indicates the Cu content (mass%) in the powder metal material, [Mn] indicates the Mn content (mass%) in the powder metal material, [Mg] indicates the Mg content (mass%) in the powder metal material, [Zn] indicates the Zn content (mass%) in the powder metal material, [Ti] indicates the Ti content (mass%) in the powder metal material, [Ni] indicates the Ni content (mass%) in the powder metal material, [Zr] indicates the Zr content (mass%) in the powder metal material, and [Sc] indicates the Sc content (mass%) in the powder metal material.

[0010] The regression equation above was obtained by multiple regression analysis. Specifically, 21 types of aluminum alloy powders with different chemical compositions were prepared, and the absorption rate of a 1081 nm laser was measured. Multiple regression analysis was then performed using the content (mass %) of the atoms contained in the powders as the explanatory variable and the laser absorption rate as the dependent variable. Figure 1 is a graph showing the relationship between the measured absorption rate of aluminum alloy powder under a laser (wavelength 1081 nm) and the calculated value using the regression equation described above. As shown in Figure 1, there is little variation between the calculated values ​​using the above regression equation and the measured values, indicating that the accuracy of the above regression equation is good.

[0011] The powder metal material of the present invention has a high laser absorption rate, and when used in additive manufacturing (preferably additive manufacturing using a 3D printer), it offers faster manufacturing speeds, superior productivity, and excellent energy efficiency compared to conventional materials.

[0012] The absorption rate of the powder metal material of the present invention, as determined by the above regression equation, is preferably 70% or higher. Furthermore, the absorption rate of the powder metal material of the present invention, as determined by the above regression equation, may be 90% or less, or 85% or less.

[0013] The aluminum alloy of the powder metal material of the present invention is, by mass%, Ti: 0.1~3.0%, Zr: 3.0% or less, Si: 3.0 - 20.0%, Cu: 0.1 - 10.0%, Mn: 1.0% or less, Mg: 0.1 - 3.0%, Ni: 3.0% or less, Cr: 0.5% or less, Zn: 0.05 - 3.0%, Fe: 0.1 - 5.0%, Sc: 3.0% or less and preferably contains the following. Unless otherwise specified, the content of each alloy element is a value based on a mass standard with the entire aluminum alloy being 100%.

[0014] The powder metal material of the present invention can increase the specific resistance and the laser absorption rate by actively containing elements that become the above-mentioned impurities with respect to Al, which is the main constituent element of the aluminum alloy. Since the powder metal material of the present invention may actively contain elements that become impurities, for example, it can also be manufactured using secondary ingots containing a large amount of impurities such as Fe and Zn, or recycled materials containing a large amount of impurities as raw materials, which is also preferable from the viewpoints of reducing carbon dioxide emissions during manufacturing, resource conservation, and environmental load reduction.

[0015] The aluminum alloy of the powder metal material of the present invention preferably has the above chemical composition, with the balance consisting of Al and unavoidable impurities. The content of Al in the aluminum alloy of the powder metal material of the present invention is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more.

[0016] Unavoidable impurities are components that can inevitably be mixed in from raw materials and the environment when manufacturing the aluminum alloy in the present invention. The content of unavoidable impurities is usually 2% by mass or less.

[0017] The Ti content in the aluminum alloy is preferably 0.1 to 3.0%, more preferably 0.5 to 2.5%, and even more preferably 1.0 to 2.0%.

[0018] The Zr content in the aluminum alloy is preferably 3.0% or less, more preferably 2.0% or less, and even more preferably 1.5% or less. The lower limit of the Zr content in the aluminum alloy is not particularly limited and can be 0% by mass or more. The aluminum alloy does not need to contain Zr. If the aluminum alloy contains Zr, the Zr content may be 0.7 to 2.5% or 1.0 to 1.3%.

[0019] The Si content in the aluminum alloy is preferably 3.0 to 20.0%, more preferably 5.0 to 17.0%, and even more preferably 8.0 to 15.0%.

[0020] The Cu content in the aluminum alloy is preferably 0.1 to 10.0%, more preferably 1.0 to 7.0%, and even more preferably 3.0 to 5.0%.

[0021] The Mn content in the aluminum alloy is preferably 1.0% or less, more preferably 0.03 to 0.8%, and even more preferably 0.1 to 0.5%.

[0022] The Mg content in the aluminum alloy is preferably 0.1 to 3.0%, more preferably 0.2 to 2.0%, and even more preferably 0.3 to 1.0%.

[0023] The nickel content in the aluminum alloy is preferably 3.0% or less, more preferably 2.0% or less, and even more preferably 1.5% or less. The lower limit of the nickel content in the aluminum alloy is not particularly limited and can be 0% by mass or more. The aluminum alloy does not need to contain nickel. If the aluminum alloy contains nickel, the nickel content may be 0.1 to 2.5% or 0.5 to 1.0%.

[0024] The Cr content in the aluminum alloy is preferably 0.5% or less, more preferably 0.3% or less, and even more preferably 0.1% or less. The lower limit of the Cr content in the aluminum alloy is not particularly limited and can be 0% by mass or more. The aluminum alloy does not need to contain Cr. If the aluminum alloy contains Cr, the Cr content may be 0.01-0.2% or 0.03-0.1%.

[0025] The Zn content in the aluminum alloy is preferably 0.05 to 3.0%, more preferably 0.1 to 2.0%, and even more preferably 0.2 to 1.0%.

[0026] The Fe content in the aluminum alloy is preferably 0.1 to 5.0%, more preferably 0.5 to 3.0%, and even more preferably 1.0 to 2.0%.

[0027] The Sc content in the aluminum alloy is preferably 3.0% or less, more preferably 2.0% or less, and even more preferably 1.0% or less. The lower limit of the Sc content in the aluminum alloy is not particularly limited and can be 0% by mass or more. The aluminum alloy may not contain Sc at all.

[0028] The particle size of the powder metal material of the present invention is not particularly limited, and is a known particle size suitable for additive manufacturing (for example, the volume-average particle size (D) measured by a laser diffraction particle size distribution analyzer). 50 The thickness can be set to 10-200 μm, for example.

[0029] The method for producing the powder metal material of the present invention is not particularly limited, and known methods (for example, gas atomization, plasma atomization, centrifugal atomization, etc.) can be employed.

[0030] [Additive Manufacturing Method] The additive manufacturing method of the present invention preferably uses the above-mentioned powder metal material, and it is particularly preferable to use the above-mentioned powder metal material to manufacture the object with a 3D printer. The additive manufacturing method of the present invention offers faster manufacturing speed, superior productivity, and better energy efficiency compared to conventional metal powder additive manufacturing methods. Publicly available 3D printers can be used. The additive manufacturing method is not particularly limited, but for example, powder bed fusion and directed energy deposition are preferred.

[0031] The products manufactured by the additive manufacturing method of the present invention can be used for a variety of applications, such as automotive parts. [Examples]

[0032] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited thereto.

[0033] Aluminum alloy powder with the composition shown in Table 1 (average particle size 40 μm) was used, and the absorption rate of the laser was measured using a spectrophotometer manufactured by Hitachi High-Tech Science Corporation after irradiation with a laser at a wavelength of 1081 nm. In Table 1, "Bal" indicates "remainder".

[0034] Commercially available aluminum alloy powders were used for Comparative Example 1 and Comparative Example 2.

[0035] The measurement results (actual values) of the absorption rate are shown in Table 1.

[0036] [Table 1]

[0037] Table 1 shows that the laser absorption rates of the aluminum alloy powders in Examples 1-4 are higher than those of the aluminum alloy powders in Comparative Examples 1-2. This invention makes it possible to increase the laser absorption rate of aluminum alloy powder for metal additive manufacturing compared to conventional products, thereby improving the manufacturing speed, reducing costs, and reducing carbon dioxide emissions.

[0038] Although embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and modifications, improvements, etc., can be made as appropriate.

[0039] Furthermore, this specification contains at least the following information:

[0040] (1) A powder metal material for additive manufacturing made of an aluminum alloy, wherein the absorption rate determined by the following regression equation is 65% or more. Absorption rate (%)=23.5+1.9[Si]+7.4[Fe]-4.0[Cu]+109.6[Mn]+45.1[Mg]-14.5[Zn]-14.2[Ti]+2.6[Ni]-3.0[Zr]-218.1[Sc] In the above formula, [ ] indicates the content (mass%) of each element.

[0041] According to (1), the laser has a high absorption rate, and when used in additive manufacturing (preferably additive manufacturing using a 3D printer), the manufacturing speed is faster than conventional methods, resulting in superior productivity and energy efficiency.

[0042] (2) The aluminum alloy is In mass percent, Ti: 0.1~3.0%, Zr: 3.0% or less, Si: 3.0~20.0%, Cu: 0.1~10.0%, Mn: 1.0% or less, Mg: 0.1~3.0%, Ni: 3.0% or less, Cr: 0.5% or less, Zn: 0.05~3.0%, Fe: 0.1~5.0%, Sc:3.0% or less The powder metal material described in (1), which contains the above.

[0043] According to (2), by actively including elements that act as impurities in relation to Al, the main constituent element of the aluminum alloy, the resistivity can be increased and the laser absorption rate can be increased. Furthermore, since it is possible to actively include elements that act as impurities, it is possible to manufacture the alloy using secondary metals containing many impurities such as Fe and Zn, or recycled materials containing many impurities, as raw materials, which is preferable from the viewpoint of reducing carbon dioxide emissions during manufacturing, conserving resources, and reducing environmental impact.

[0044] (3) A method of additive manufacturing in which a 3D printer is used to fabricate a material using the powder metal material described in (1) or (2).

[0045] According to (3), the molding speed is faster than conventional methods, productivity is superior, and energy efficiency is also superior.

Claims

1. A powder metal material for additive manufacturing made of aluminum alloy, wherein the absorption rate determined by the following regression equation is 65% or more. The aforementioned aluminum alloy, In mass percent, Ti: 0.1-2.0%, Zr: 2.0% or less, Si: 8.0 to 15.0%, Cu: 3.0-5.0%, Mn: 0.5% or less, Mg: 0.1-3.0%, Ni: 1.5% or less, Cr: 0.1% or less, Zn: 1.0% or less, Fe: 2.0% or less, A powder metal material containing [a certain substance], with the remainder consisting of Al and unavoidable impurities. Absorption rate (%) = 23.5 + 1.9 [Si] + 7.4 [Fe] - 4.0 [Cu] + 109.6 [Mn] + 45.1 [Mg] - 14.5 [Zn] - 14.2 [Ti] + 2.6 [Ni] - 3.0 [Zr] - 218.1 [Sc] In the above formula, [ ] indicates the content (mass %) of each element.

2. A method of additive manufacturing using a 3D printer to create an object using the powder metal material described in claim 1.

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