阅读说明：本技术 一种铝合金粉末与制备方法及其在激光增材制造中的应用 (Aluminum alloy powder, preparation method and application of aluminum alloy powder in laser additive manufacturing ) 是由 王协彬 刘相法 高通 于 2020-12-03 设计创作，主要内容包括：本发明公开了一种铝合金粉末与制备方法及其在激光增材制造中的应用,其方法为采用气雾化方法将中间合金制成中间合金球形粉末,根据激光增材制造工艺对中间合金球形粉末进行筛分,将筛分后的中间合金球形粉末与Al-Si合金的球形粉末进行混合；其中,中间合金为Al-Ti-C中间合金、Al-Ti-B中间合金或Al-Ti-C-B中间合金的一种或几种。本发明方法制备的铝合金粉末适用于激光增材制造技术,可以极大地细化激光增材制造材料组织,并提高其力学性能。(The invention discloses aluminum alloy powder, a preparation method and application thereof in laser additive manufacturing, wherein the method comprises the steps of preparing intermediate alloy into intermediate alloy spherical powder by adopting an air atomization method, screening the intermediate alloy spherical powder according to a laser additive manufacturing process, and mixing the screened intermediate alloy spherical powder with Al-Si alloy spherical powder; wherein the intermediate alloy is one or more of Al-Ti-C intermediate alloy, Al-Ti-B intermediate alloy or Al-Ti-C-B intermediate alloy. The aluminum alloy powder prepared by the method is suitable for a laser additive manufacturing technology, can greatly refine the structure of a laser additive manufacturing material, and improves the mechanical property of the laser additive manufacturing material.)

1. A preparation method of aluminum alloy powder is characterized in that a gas atomization method is adopted to prepare intermediate alloy into intermediate alloy spherical powder, the intermediate alloy spherical powder is screened according to a laser additive manufacturing process, and the screened intermediate alloy spherical powder is mixed with spherical powder of Al-Si alloy; wherein the intermediate alloy is one or more of Al-Ti-C intermediate alloy, Al-Ti-B intermediate alloy or Al-Ti-C-B intermediate alloy.

2. The method for producing an aluminum alloy powder as recited in claim 1, wherein the intermediate alloy has a Ti mass fraction of not less than 3%.

3. The method for producing an aluminum alloy powder as recited in claim 1, wherein the mixing is performed by dry mechanical mixing; the mixing time is 1min to 100 hours.

4. The method for producing an aluminum alloy powder as recited in claim 1, wherein the amount of the spherical powder of the master alloy added is 0.5 to 50% by mass of the total mass of the powders after mixing.

5. The method for producing an aluminum alloy powder as recited in claim 1, wherein the particle diameter of the sieved spherical master alloy powder is 1 to 300 μm.

6. The method for producing an aluminum alloy powder as recited in claim 1, wherein the particle diameter of the sieved spherical powder of the master alloy is 15 to 53 μm in a powder bed melting process using laser; when the directional energy deposition process of laser is adopted, the particle size of the screened intermediate alloy spherical powder is 53-105 microns.

7. The method for producing an aluminum alloy powder as recited in claim 1, wherein the gas atomization method comprises the steps of melting the master alloy to obtain a melt, and gas-atomizing the melt using an inert gas as a medium;

preferably, the temperature of the melt is kept to be 660-1500 ℃;

preferably, the gas pressure during gas atomization is 0.1-15 MPa.

8. An aluminum alloy powder obtained by the method for producing an aluminum alloy powder according to any one of claims 1 to 7.

9. Use of the aluminium alloy powder according to claim 8 in laser additive manufacturing.

10. An aluminum alloy structural member obtained by laser additive manufacturing using the aluminum alloy powder according to claim 8.

Technical Field

The invention belongs to the field of metal materials and the field of additive manufacturing, and relates to aluminum alloy powder, a preparation method and application thereof in laser additive manufacturing.

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

The laser additive manufacturing technology adopts laser beams to melt/solidify and accumulate metal powder layer by layer to form, and can directly manufacture complex metal components according to a three-dimensional model. As a novel intelligent manufacturing technology, laser additive manufacturing has received great attention and developed rapidly at home and abroad. The laser additive manufacturing aluminum alloy can not only realize the weight reduction of the structure through the structural optimization, but also realize the weight reduction of the material due to the lower density of the aluminum alloy. Therefore, the laser additive manufacturing aluminum alloy has wide application prospect in the fields of aerospace, transportation and the like. However, the aluminum alloy powder suitable for laser additive manufacturing at present is generally an Al-Si series, belongs to a cast aluminum alloy system, has low strength and poor plasticity on the whole, and cannot meet the requirements of the fields of aerospace and the like on light-weight, high-strength and high-toughness alloy components. Therefore, the development of a high-strength aluminum alloy powder system suitable for laser additive manufacturing is of great significance.

The introduction of nucleation particles promotes the nucleation of aluminum alloy grains in the rapid solidification process of laser additive manufacturing, and is an effective means for refining the aluminum alloy structure, inhibiting thermal cracks and improving the strength of the aluminum alloy. The passenger air company, a subordinate company, APWorks, adds Sc elements to a 5 xxx series aluminum alloy to form Al during solidification₃The Sc particles are used as nucleation particles, so that the aluminum alloy structure is refined and the strength of the aluminum alloy structure is improved. However, Sc is expensive and the above method greatly increases the material cost. The literature (Martin et al, Nature,2017,549: 365-. However, in the above method, the element Zr needs to be ZrH₂Added in the form of a powder. The introduction of the H element can bring adverse effects on the mechanical property and the fatigue property of the material.

In recent years, in-situ reaction is adopted to introduce TiB into aluminum alloy matrix₂The particles improve the strength of the aluminum alloy manufactured by the laser additiveHas received a great deal of attention. Patent application CN108372292A discloses "an aluminum-based composite powder for laser additive manufacturing and a preparation method thereof", patent application CN108315577A discloses "7 xxx series in-situ aluminum-based composite powder for laser additive manufacturing and preparation", patent application CN108380865A discloses "6 xxx series in-situ aluminum-based composite powder for laser additive manufacturing and preparation", patent application CN108330347A discloses "a preparation method for preparing an aluminum-based composite material based on laser selective melting", and patent application CN108356259A discloses "a nano aluminum-based composite powder and a preparation method thereof". The methods disclosed in the above patents all use molten salt reaction to generate TiB in situ in the aluminum alloy matrix₂And (4) a reinforcing phase. According to published literature (X.Li et al, actaMaterialia,2017,129:183-193.), the use of the above-described method using molten salt reaction requires the addition of a relatively large amount of TiB₂The granule can obtain good effect. However, the inventors have found that TiB₂Agglomeration of particles in the material can impair the fatigue properties of the monolithic component. In addition, the molten salt reaction causes problems such as environmental pollution.

Disclosure of Invention

In order to solve the disadvantages of the prior art, the object of the present invention is to provide an aluminum alloy powder and a method for preparing the same and the use thereof in laser additive manufacturing, wherein one or more of Al-Ti-C, Al-Ti-B or Al-Ti-C-B master alloy powders are mechanically mixed with commonly used Al-Si alloy (such as AlSi10Mg, AlSi7Mg, AlSi12, etc.) powders by introducing TiC or/and TiB₂The nano particles are used as nucleation particles to promote nucleation of aluminum alloy grains in the solidification process, so that the aluminum alloy structure is refined, and the strength and the plasticity of the final aluminum alloy member are improved. The method can avoid adopting a molten salt reaction method, is simple and easy in process, low in cost and high in efficiency, and is suitable for large-scale batch production.

In order to achieve the purpose, the technical scheme of the invention is as follows:

on one hand, the preparation method of the aluminum alloy powder comprises the steps of firstly preparing intermediate alloy into intermediate alloy spherical powder by adopting an air atomization method, screening the intermediate alloy spherical powder according to a laser additive manufacturing process, and mechanically mixing the screened intermediate alloy spherical powder with spherical powder of common Al-Si alloys (such as AlSi10Mg, AlSi7Mg, AlSi12 and the like); wherein the intermediate alloy is one or more of Al-Ti-C intermediate alloy, Al-Ti-B intermediate alloy or Al-Ti-C-B intermediate alloy.

The invention firstly prepares Al-Ti-C, Al-Ti-B or Al-Ti-C-B intermediate alloy into spherical powder by a gas atomization method, selects intermediate alloy powder with proper grain diameter and mechanically mixes the intermediate alloy powder with the spherical powder of common Al-Si alloy (such as AlSi10Mg, AlSi7Mg, AlSi12 and the like). In the laser additive manufacturing process, the master alloy powder in the mixed powder releases TiC or/and TiB₂The nano particles as nucleation particles can greatly refine the microstructure of the Al-Si alloy manufactured by laser additive manufacturing, thereby improving the strength and the plasticity of the Al-Si alloy.

In another aspect, an aluminum alloy powder is obtained by the above method of preparing an aluminum alloy powder.

In a third aspect, use of an aluminium alloy powder as described above in laser additive manufacturing.

In a fourth aspect, an aluminum alloy member is obtained by performing laser additive manufacturing using the aluminum alloy powder.

The invention has the beneficial effects that:

1) the preparation method of the aluminum alloy powder provided by the invention adopts mechanical mixing of the intermediate alloy powder and the Al-Si alloy powder, and TiC or TiB is released by the intermediate alloy in the laser additive manufacturing process₂The particles are used as nucleation particles to refine the aluminum alloy structure, so that the strength and the plasticity of the additive manufacturing aluminum alloy component are improved.

2) The invention provides a preparation method of an aluminum alloy powder material suitable for an additive manufacturing process, which is obtained by adding a certain amount of one or more intermediate alloy powders of Al-Ti-C, Al-Ti-B, Al-Ti-C-B into Al-Si series aluminum alloy (such as AlSi10Mg, AlSi7Mg or AlSi12 and the like) powder and mechanically mixing. Mechanical mixing is adopted instead of molten salt reaction, and the method is simple, easy to operate and environment-friendly.

3) Because the master alloy powder and the Al-Si-Mg alloy powder are both aluminum alloyThe powder can be mixed very uniformly in the subsequent powder mixing process. In the subsequent laser additive manufacturing process, evenly distributed TiC or TiB can be obtained₂Particles, inhibiting TiC or TiB₂The agglomeration of the particles obviously improves the microstructure thinning effect and is also beneficial to improving the fatigue performance of the component. 4) When adding master alloy powders containing Al-Ti-C or Al-Ti-C-B, TiC is the dominant nucleation site. Compared with the TiB2 (close-packed hexagonal structure) particles, the TiC crystal structure (face-centered cubic structure, lattice constant of 0.433nm) is consistent with the aluminum crystal structure (face-centered cubic structure, lattice constant of 0.405nm), and the difference of the lattice parameters is very small, so that higher nucleation efficiency can be provided.

5) The base body of the aluminum alloy powder is Al-Si alloy (such as AlSi10Mg, AlSi7Mg, AlSi12 and the like) commonly used in the field of laser additive manufacturing, and has better laser additive manufacturing process adaptability compared with aluminum alloy powder of 7 XXX, 2 XXX and the like.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a scanning electron micrograph of powders of Al-Ti-C-B master alloy prepared in examples and after mixing the master alloy powders with Al-Si-Mg alloy powders; wherein (a) is an overall photograph of the Al-Ti-C-B master alloy powder; (b) is a section structure photo of single powder of the Al-Ti-C-B intermediate alloy; (c) is a photograph of the whole of the mixed powder, in which the content of the Al-Ti-C-B master alloy powder is 10%.

FIG. 2 is a photograph of an electron backscattered diffraction structure of the corresponding powder formed by a selective laser melting process in the example; wherein (a) is a structure photograph of the AlSi10Mg alloy without the addition of the master alloy powder; (b) the structure picture of the AlSi10Mg alloy after adding the master alloy powder.

FIG. 3 is a tensile curve of the test pieces in the examples. Tensile strength is greater than 480MPa, and elongation is greater than 10%.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

In view of the existing method for generating TiB in situ in aluminum alloy matrix by adopting molten salt reaction₂Method for enhancing the phase presents TiB₂The invention provides aluminum alloy powder, a preparation method and application thereof in laser additive manufacturing, and solves the problems of more particle addition, environmental pollution and the like, and the problem of high cost caused by adding elements such as Sc, Zr and the like by a metallurgical method.

In a typical embodiment of the present invention, a method for preparing an aluminum alloy powder is provided, which comprises preparing an intermediate alloy into an intermediate alloy spherical powder by a gas atomization method, sieving the intermediate alloy spherical powder according to a laser additive manufacturing process, and mixing the sieved intermediate alloy spherical powder with a spherical powder of a common Al — Si alloy (e.g., AlSi10Mg, AlSi7Mg, AlSi12, etc.); wherein the intermediate alloy is one or more of Al-Ti-C intermediate alloy, Al-Ti-B intermediate alloy or Al-Ti-C-B intermediate alloy.

The invention firstly prepares Al-Ti-C, Al-Ti-B or Al-Ti-C-B master alloy into spherical powder by a gas atomization method. Then selecting intermediate alloy powder with proper grain size and mechanically mixing the intermediate alloy powder with Al-Si series alloy spherical powder. In the laser additive manufacturing process, the master alloy powder in the mixed powder releases TiC or/and TiB₂Nanoparticles, nanoparticlesAs nucleation particles, the structure of the Al-Si series alloy manufactured by laser additive manufacturing can be greatly refined, and the strength and the plasticity are further improved.

In some examples of this embodiment, the master alloy has a mass fraction of Ti of not less than 3%.

In some examples of this embodiment, the method of gas atomization comprises the steps of melting the master alloy to obtain a melt, and gas atomizing the melt using an inert gas as a medium. The inert gas of the present invention is, for example, helium, argon, etc.

In one or more embodiments, the temperature of the master alloy melt is maintained between 660 and 1500 ℃. The melt temperature can improve the yield of the intermediate alloy spherical powder obtained by gas atomization, and particularly aims at the intermediate alloy with higher Ti content.

In one or more embodiments, the gas pressure during the gas atomization is 0.1-15 MPa. The gas atomization under the gas pressure can improve the yield of the spherical powder of the intermediate alloy, particularly the intermediate alloy with higher Ti content.

In some examples of this embodiment, the sieved spherical master alloy powder has a particle size of 1 to 300. mu.m.

In some examples of this embodiment, when a laser powder bed melting process (i.e., a selective laser melting process) is used, the particle size of the sieved spherical master alloy powder is 15-53 μm; when a laser directional energy deposition process (namely a laser coaxial powder feeding additive manufacturing process) is adopted, the particle size of the screened intermediate alloy spherical powder is 53-105 micrometers.

In some examples of this embodiment, the Al-Si-Mg alloy includes, in mass%, 0.2 to 7% of Mg0.5 to 25% of Si, and the balance being Al.

Spherical powders of Al-Si-Mg alloys are commercially available or can be prepared by themselves. The preparation method comprises the following specific processes: melting the aluminum alloy in a crucible, keeping the temperature of the melt at 660-1500 ℃, and carrying out gas atomization by using high-purity Ar gas or high-purity He gas as a medium, wherein the gas pressure is 0.1-15 MPa during atomization.

In some examples of this embodiment, the spherical powder of the Al-Si-Mg alloy has a particle size of 1 to 300 μm.

In some examples of this embodiment, the method of mixing is dry mechanical mixing.

In some examples of this embodiment, the time of mixing is from 1min to 100 hours.

In some examples of this embodiment, the amount of the spherical master alloy powder added is 0.5 to 50% of the total mass of the mixed powder.

In some examples of this embodiment, the sieved spherical powder of master alloy is in accordance with the particle size range of the spherical powder of Al-Si-Mg alloy.

In another embodiment of the present invention, there is provided an aluminum alloy powder obtained by the above method for producing an aluminum alloy powder.

In a third embodiment of the present invention, an application of the aluminum alloy powder in laser additive manufacturing is provided. The main mechanism for improving the strength of the laser additive manufactured aluminum alloy is as follows: by adding Al-TiC, Al-Ti-B or Al-Ti-C-B intermediate alloy, the intermediate alloy can release a large amount of TiC and TiB in the subsequent laser additive manufacturing process₂And the like. The nano particles are used as heterogeneous nucleation particles to promote nucleation of the aluminum alloy in the solidification process and refine the aluminum alloy structure, so that the strength and plasticity of the aluminum alloy manufactured by the laser additive are improved.

In a fourth embodiment of the invention, an aluminum alloy member is provided, which is obtained by laser additive manufacturing using the aluminum alloy powder.

In order to make the technical solutions of the present invention more clearly understood by those skilled in the art, the technical solutions of the present invention will be described in detail below with reference to specific embodiments.

The following examples were verified using Al-5Ti-0.3C-0.2B master alloy and AlSi10Mg aluminum alloy. Generally, the mass fraction of Ti in the Al-5Ti-0.3C-0.2B intermediate alloy is 4.6-5.4%, the mass fraction of C is 0.25-0.35%, and the mass fraction of B is 0.15-0.25%. The Al-Si 10Mg aluminum alloy spherical powder contains 9-10% of Si and 0.4-0.8% of Mg by mass.

Example 1

Preparing intermediate alloy spherical powder by adopting vacuum induction melting gas atomization: heating and melting Al-5Ti-0.3C-0.2B intermediate alloy, preserving heat at 850 ℃, and then carrying out gas atomization by adopting high-purity argon, wherein the pressure of the gas is 3MPa during atomization. And screening the intermediate alloy powder obtained by gas atomization, and selecting intermediate alloy spherical powder with the powder particle size range of 15-53 mu m. Wherein, the mass fraction of Ti in the Al-5Ti-0.3C-0.2B intermediate alloy is 4.9 percent, the mass fraction of C is 0.32 percent, and the mass fraction of B is 0.19 percent.

And screening AlSi10Mg aluminum alloy spherical powder with the grain diameter range of 15-53 mu m, wherein the mass fraction of Si is 10%, the mass fraction of Mg is 0.45%, and the balance is Al. And mixing the Al-5Ti-0.3C-0.2B master alloy spherical powder with the AlSi10Mg alloy spherical powder by adopting a mechanical mixing method. Wherein the mass fraction of the master alloy spherical powder is 10%. And (3) adopting a three-dimensional mixer during mixing, and mixing for 2 hours to obtain the aluminum alloy powder for laser additive manufacturing.

And (3) performance testing:

as shown in FIG. 1, the morphology of the spherical Al-5Ti-0.3C-0.2B master alloy powder prepared in example 1 and the cross-sectional morphology of the powder are shown. The grain size range of the selected Al-Ti-C-B intermediate alloy powder is 15-53 mu m. And selecting AlSi10Mg alloy powder with the grain diameter range of 15-53 mu m, and preparing mixed powder with the Al-Ti-C-B powder content of 10% by mechanical mixing.

The aluminum alloy powder prepared in this example was used for laser additive manufacturing, which was a laser-based powder bed melting process (i.e., a selective laser melting process). The additive manufacturing process parameters are as follows: the laser power is 200W, the scanning speed is 1400mm/s, the scanning interval is 80 μm, and the scanning layer thickness is 30 μm. Fig. 2a is a microstructure of AlSi10Mg powder after laser additive manufacturing and forming without addition of master alloy powder, and mainly contains typical coarse columnar crystals. FIG. 2B is a microstructure diagram of the Al-Ti-C-B master alloy powder added with 10% by mass after laser additive manufacturing and molding, which mainly contains fine equiaxed crystals with an average grain size of 3 μm. It can be seen that the addition of the master alloy powder can greatly refine the texture of the AlSi10Mg alloy manufactured by laser additive manufacturing.

Fig. 3 is a mechanical property curve of the material formed by the selective laser melting process of the additive manufacturing high-strength aluminum alloy powder obtained in example 1. The tensile strength of the material is greater than 480MPa, and the elongation is greater than 10%.

Example 2

Preparing intermediate alloy spherical powder by adopting vacuum induction melting gas atomization: heating and melting Al-5Ti-0.3C-0.2B intermediate alloy, preserving heat at 850 ℃, and then carrying out gas atomization by adopting high-purity argon, wherein the pressure of the gas is 3MPa during atomization. And screening the intermediate alloy powder obtained by gas atomization, and selecting intermediate alloy spherical powder with the powder particle size range of 53-105 microns.

And (3) screening AlSi10Mg aluminum alloy spherical powder with the particle size range of 53-105 mu m, wherein the mass fraction of Si is 9.5%, the mass fraction of Mg is 0.45%, and the balance is Al. And mixing the Al-5Ti-0.3C-0.2B master alloy spherical powder with the AlSi10Mg alloy spherical powder by adopting a mechanical mixing method. Wherein the mass fraction of the master alloy spherical powder is 10%. And (3) adopting a three-dimensional mixer during mixing, and mixing for 2 hours to obtain the aluminum alloy powder for laser additive manufacturing.

And (3) performance testing:

the aluminum alloy powder prepared by the embodiment is used for laser additive manufacturing, and the additive manufacturing process is a laser-based directional energy deposition process (namely a laser coaxial powder feeding additive manufacturing process). The additive manufacturing process parameters are as follows: the laser power is 1500W, the scanning speed is 400mm/min, and the powder feeding speed is 6 g/min.

The tensile strength of the laser additive manufacturing material can reach 430MPa, and the elongation is more than 8%.

Example 3

Preparing intermediate alloy spherical powder by adopting vacuum induction melting gas atomization: heating and melting the Al-5Ti-0.35C intermediate alloy, preserving heat at 850 ℃, and then carrying out gas atomization by adopting high-purity argon, wherein the pressure of the gas is 3MPa during atomization. And screening the intermediate alloy powder obtained by gas atomization, and selecting intermediate alloy spherical powder with the powder particle size range of 15-53 mu m. Wherein, the mass fraction of Ti in the Al-Ti-C intermediate alloy is 5 percent, and the mass fraction of C is 0.35 percent.

And screening AlSi10Mg aluminum alloy spherical powder with the grain diameter range of 15-53 mu m, wherein the mass fraction of Si is 9.5%, the mass fraction of Mg is 0.45%, and the balance is Al. And mixing the Al-Ti-C master alloy spherical powder with the AlSi10Mg alloy spherical powder by adopting a mechanical mixing method. Wherein the mass fraction of the master alloy spherical powder is 10%. And (3) adopting a three-dimensional mixer during mixing, and mixing for 4 hours to obtain the aluminum alloy powder for laser additive manufacturing.

And (3) performance testing:

the aluminum alloy powder prepared in this example was used for laser additive manufacturing, which was a laser-based powder bed melting process (i.e., a selective laser melting process). The additive manufacturing process parameters are as follows: the laser power was 200W, the scanning speed was 1200mm/s, the scanning pitch was 80 μm, and the scanning layer thickness was 30 μm. The material produced by the additive mainly contains fine isometric crystals, and the average grain size is 3.2 mu m. It can be seen that the Al-Si-Mg alloy structure manufactured by laser additive manufacturing can be greatly refined after the intermediate alloy powder is added. The tensile strength of the additive manufacturing material can reach 480MPa, and the elongation is more than 9%.

Example 4

Preparing intermediate alloy spherical powder by adopting vacuum induction melting gas atomization: heating and melting the Al-Ti-B intermediate alloy, preserving heat at 850 ℃, and then carrying out gas atomization by adopting high-purity argon, wherein the pressure of the gas is 3MPa during atomization. And screening the intermediate alloy powder obtained by gas atomization, and selecting intermediate alloy spherical powder with the powder particle size range of 15-53 mu m. Wherein, the mass fraction of Ti in the Al-Ti-B intermediate alloy is 4.9 percent, and the mass fraction of B is 1.0 percent.

And screening AlSi10Mg aluminum alloy spherical powder with the grain diameter range of 15-53 mu m, wherein the mass fraction of Si is 10%, the mass fraction of Mg is 0.5%, and the balance is Al. And mixing the Al-Ti-B master alloy spherical powder with the AlSi10Mg alloy spherical powder by adopting a mechanical mixing method. Wherein the mass fraction of the master alloy spherical powder is 10%. And (3) adopting a three-dimensional mixer during mixing, and mixing for 4 hours to obtain the aluminum alloy powder for laser additive manufacturing.

And (3) performance testing:

the aluminum alloy powder prepared in this example was used for laser additive manufacturing, which was a laser-based powder bed melting process (i.e., a selective laser melting process). The additive manufacturing process parameters are as follows: the laser power was 200W, the scanning speed was 1200mm/s, the scanning pitch was 80 μm, and the scanning layer thickness was 30 μm. The material produced by the additive mainly contains fine isometric crystals, and the average grain size is 5 mu m. It can be seen that the Al-Si-Mg alloy structure manufactured by laser additive manufacturing can be greatly refined after the intermediate alloy powder is added. The tensile strength of the additive manufacturing material can reach 450MPa, and the elongation is more than 8%.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.