Anodized aluminum alloy powder for laser additive manufacturing

Abstract

The present invention provides an anodized aluminum alloy powder for laser additive manufacturing, which belongs to the technical field of aluminum alloys. The aluminum alloy powder includes the following components in mass percentage: Mg2‑5%, Mn0.2‑1.5%, Zr0.5‑1.5%, Cu0.05‑0.20%, Fe0.1‑0.2%, and the rest is Al. The aluminum alloy powder proposed by the present invention can be used for additive manufacturing, and can also be anodized. The surface oxide film of the obtained finished product is uniform and has good glossiness, which is beneficial to subsequent color plating. The hollow powder rate of the aluminum alloy powder provided by the present invention is low, which effectively reduces the probability of defects such as pores and cracks in the additive manufacturing metal parts, and improves the performance and life of the parts.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum alloys, and in particular relates to an anodized aluminum alloy powder for laser additive manufacturing. Background Art

[0002] Aluminum alloys are widely used in automobile manufacturing, aerospace and rail transportation due to their advantages such as low density, excellent mechanical properties, good corrosion resistance and high weldability. Additive manufacturing technology is a technology that uses materials to gradually accumulate to manufacture solid parts. In recent years, additive manufacturing technology has achieved rapid development. However, it is difficult to use ordinary aluminum alloys for additive manufacturing, which is related to the special physical properties of aluminum alloys (low density, low laser absorption rate, high thermal conductivity and easy oxidation, etc.). The solidification temperature range of forged aluminum alloys is large, and the stress generated during rapid solidification can easily lead to cracking and deformation. Cast aluminum alloys contain eutectic elements (such as Si) and have a small solidification temperature range, so they have a small tendency to hot cracking and good forming performance. Therefore, cast Al-Si alloys are the earliest studied aluminum alloys with the most mature additive manufacturing process.

[0003] The process of using aluminum alloy products as anodes, placing them in electrolyte solutions for power treatment, and using electrolysis to form an aluminum oxide film on their surface is called anodizing of aluminum alloys. After anodizing, an oxide film can be formed on the surface of the aluminum alloy. Compared with the natural oxide film of the aluminum alloy, its corrosion resistance, wear resistance and decorative properties are significantly improved and enhanced. However, since the silicon content in the cast Al-Si alloy is as high as 10%-12%, most of the silicon in the matrix exists in the form of a single substance and is relatively dispersed in the eutectic structure of the matrix. The anodized film generated by conventional anodizing process parameters has different pore sizes and is not easy to color. And because silicon is a non-metal, it neither dissolves nor reacts chemically during the anodizing process, forming silicon ash on the surface. The surface is dark after anodizing, which is more difficult to anodize than other aluminum alloys. Even if the metal coloring is successful, the color of the oxide produced is relatively single and the aesthetics are poor.

[0004] When using aluminum alloy powder in laser additive manufacturing, a series of technical problems may be encountered. These problems are mainly related to the powder characteristics, performance during processing and the quality of the final product. Common technical problems are: (1) Powder fluidity: The fluidity of aluminum alloy powder is crucial to ensure uniform powder spreading and improve molding accuracy. If the fluidity is poor, it may lead to uneven powder spreading and affect the interlayer bonding quality. (2) Powder particle size distribution: The particle size distribution of the powder directly affects the material fluidity and molten pool stability during laser melting. Uneven particle size distribution may cause defects such as pores and cracks inside the molded part. (3) Metallurgical quality: Metallurgical defects such as pores and unfused areas may occur during laser additive manufacturing. These defects will reduce the mechanical properties and durability of the parts. (4) Surface quality: The surface quality of the molded part may be affected by the powder characteristics and may appear rough or uneven. The difficulty of post-processing may increase, such as grinding and polishing. (5) Microstructure: The microstructure formed during laser additive manufacturing may be different from that of traditional cast or forged materials. Changes in microstructure may affect the performance of the material. Although the existing laser additive manufacturing using aluminum alloy powder can achieve good overall performance, there is still room for improvement in material strength.

[0005] Therefore, there is an urgent need for an anodized aluminum alloy powder for laser additive manufacturing. Summary of the invention

[0006] The purpose of the present invention is to provide anodized aluminum alloy powder for laser additive manufacturing.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] Anodized aluminum alloy powder for laser additive manufacturing comprises the following components in percentage by mass: Mg 2-5%, Mn 0.2-1.5%, Zr 0.5-1.5%, Cu 0.05-0.20%, Fe 0.1-0.2%, and the remainder is Al.

[0009] Furthermore, the mass ratio of Mg, Mn and Zr is (3.6-4.2):(0.3-0.9):(1.0-1.4).

[0010] At present, the commonly used additive manufacturing aluminum alloy powder materials include AlSi10Mg, AlSi7Mg, etc., and the room temperature tensile strength of the materials formed by laser melting is less than 400MPa, which cannot meet the strength requirements of the aviation and aerospace fields. The aluminum alloy powder of the present invention adds Mg, Mn, and Zr at the same time, which can improve the tensile strength of the aluminum alloy powder. The Mg element added in the present invention has a significant effect on the tensile strength of the aluminum alloy, and the Mn element added at the same time has a supplementary strengthening effect. Therefore, after adding Mn, the magnesium content can be reduced, and the hot cracking tendency can be reduced. The maximum solubility of Mn in the solid solution is 1.82%, and the alloy strength increases continuously with the increase of solubility. In the system of the present invention, when the manganese content is 0.8%, the elongation reaches the maximum value. The Zr element added at the same time can hinder the nucleation and growth process of recrystallization, have a certain strengthening effect on the alloy, and can also improve the toughness of the alloy and reduce the sensitivity to stress corrosion cracking. When the mass ratio of Mg, Mn, and Zr is (3.6-4.2): (0.3-0.9): (1.0-1.4), the aluminum alloy powder can obtain good tensile strength and elongation at the same time. However, the wear resistance of the aluminum alloy under this condition is not ideal.

[0011] Further, the sum of the mass percentages of Cu and Fe ranges from 0.19 to 0.24%.

[0012] Adding an appropriate amount of Fe element to the system of the present invention is beneficial to improving the wear resistance, high temperature performance and fatigue performance of the alloy. The added Cu element is also an important alloying element, which has a certain solid solution strengthening effect and improves the strength of the aluminum alloy through the solid solution strengthening mechanism. At the same time, adjusting the ratio of Cu and Fe in the system can optimize the wear resistance of the aluminum alloy powder. By adjusting the ratio of alloy components and other alloying elements (such as magnesium and manganese), this situation can be improved to a certain extent. The addition of an appropriate amount of copper and iron can further improve the wear resistance by forming a variety of different phases. At the same time, the yield strength can also be improved under this condition.

[0013] Furthermore, the following components are included in mass percentage: Mg 3.8%, Mn 0.8%, Zr 1.1%, Cu 0.09%, Fe 0.13%, and the rest is Al.

[0014] Furthermore, the method for preparing anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0015] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0016] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon to obtain molten metal;

[0017] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder;

[0018] (4) Screening: Screening the atomized aluminum alloy powder to obtain aluminum alloy powder;

[0019] Furthermore, the smelting conditions in step (2) are: 790-820° C., smelting for 20-25 min.

[0020] Furthermore, the atomization conditions in step (3) are as follows: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the gas outlet convergence angle is 23-26°, the melt superheat is 150-180°C, the atomization pressure is 3-3.3MPa, the atomization gas is high-purity argon, and the atomization gas temperature is 24-26°C.

[0021] Furthermore, the aluminum alloy powder with a particle size of 15-67 μm is obtained by sieving in step (4).

[0022] Furthermore, after screening in step (4), the yield of the aluminum alloy powder is ≥50%.

[0023] Furthermore, the atomization conditions in step (3) are as follows: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the gas outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 3.2 MPa, the atomization gas is high-purity argon, and the atomization gas temperature is 25°C.

[0024] The hollow powder rate of the aluminum alloy powder obtained under the atomization conditions of the present invention is low, and the optimal hollow powder rate can be achieved to be only 0.09%, which effectively reduces the probability of defects such as pores and cracks inside the additively manufactured metal parts, and improves the performance and life of the parts. The combination of alloy elements of the present invention affects the behavior characteristics of liquid metal. Under the atomization conditions of the present invention, the formation of hollow powder can be minimized and the quality of the powder can be improved.

[0025] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0026] 1. In the prior art, the cast Al-Si alloy widely used in the field of additive manufacturing has a high silicon content. Silicon neither dissolves nor reacts chemically during the anodizing process, resulting in poor anodizing effect and a dull surface. The aluminum alloy powder proposed in the present invention can be used for additive manufacturing and can also be anodized. The surface oxide film of the finished product is uniform and has good glossiness, which is beneficial to the subsequent color plating process. Figure 1 The figure shows the performance of anodized aluminum alloy powder after color plating. The surface performance is excellent and the color plating is uniform, which meets the product production requirements.

[0027] 2. Hollow powder rate is one of the key indicators of the performance of metal powder materials for additive manufacturing, such as Figure 2As shown, the hollow powder rate of the aluminum alloy powder proposed in the solution of the present invention is only 0.09%, which effectively reduces the probability of defects such as pores and cracks inside the additively manufactured metal parts, and improves the performance and life of the parts.

[0028] 3. Adding Mg, Mn and Zr to the aluminum alloy powder of the present invention can improve the tensile strength of the aluminum alloy powder. The Mg element added in the present invention significantly strengthens the tensile strength of the aluminum alloy, and the Mn element added at the same time has a supplementary strengthening effect. Therefore, after adding Mn, the magnesium content can be reduced, and the thermal cracking tendency can be reduced. The Zr element added at the same time can hinder the nucleation and growth process of recrystallization, have a certain strengthening effect on the alloy, and can also improve the toughness of the alloy and reduce the sensitivity to stress corrosion cracking. When the mass ratio of Mg, Mn and Zr is (3.6-4.2): (0.3-0.9): (1.0-1.4), the aluminum alloy powder can obtain good tensile strength and elongation at the same time.

[0029] 4. Adding an appropriate amount of Fe element to the system of the present invention is beneficial to improving the wear resistance, high temperature performance and fatigue performance of the alloy. The added Cu element is also an important alloying element, which has a certain solid solution strengthening effect, and improves the strength of the aluminum alloy through the solid solution strengthening mechanism. At the same time, adjusting the ratio of Cu and Fe in the system can optimize the wear resistance of the aluminum alloy powder. This situation can be improved to a certain extent by adjusting the alloy composition and the ratio of other alloying elements (such as magnesium and manganese). The addition of an appropriate amount of copper and iron can further improve the wear resistance by forming a variety of different phases. At the same time, the yield strength can also be improved under this condition. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a picture of the color plating effect of the product after 3D printing using the anodized aluminum alloy powder for laser additive manufacturing in Example 1 and then anodizing treatment.

[0031] Figure 2 This is a micrograph of the anodized aluminum alloy powder for laser additive manufacturing prepared in Example 1; wherein, the left picture is a metallographic picture obtained after hot embedding of the powder material; and the right picture is a statistical picture of the number of powder particles in the metallographic photograph. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Example 1

[0034] The present embodiment provides an anodized aluminum alloy powder for laser additive manufacturing, comprising the following components in mass percentage: comprising the following components in mass percentage: Mg3.8%, Mn0.8%, Zr1.1%, Cu0.09%, Fe0.13%, and the rest is Al.

[0035] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0036] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0037] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0038] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 3.2MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0039] (4) Screening: The atomized aluminum alloy powder was screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 59%.

[0040] Example 2

[0041] The present embodiment provides an anodized aluminum alloy powder for laser additive manufacturing, comprising the following components in mass percentage: Mg3.6%, Mn0.3%, Zr1.0%, Cu0.05%, Fe0.14%, and the remainder is Al.

[0042] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0043] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0044] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 790°C, smelting for 20 minutes to obtain molten metal;

[0045] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 23°, the melt superheat is 150°C, the atomization pressure is 3MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 24°C.

[0046] (4) Screening: The atomized aluminum alloy powder was screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 54%.

[0047] Example 3

[0048] The present embodiment provides an anodized aluminum alloy powder for laser additive manufacturing, comprising the following components in percentage by mass: Mg4.2%, Mn0.7%, Zr1.4%, Cu0.12%, Fe0.12%, and the remainder being Al.

[0049] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0050] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0051] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 820°C, smelting for 25 minutes to obtain molten metal;

[0052] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 26°, the melt superheat is 180°C, the atomization pressure is 3.3MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 26°C.

[0053] (4) Screening: The atomized aluminum alloy powder was screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 56%.

[0054] Comparative Example 1

[0055] The difference between this comparative example and Example 1 is: an anodized aluminum alloy powder for laser additive manufacturing, comprising the following components in mass percentage: comprising the following components in mass percentage: Mg2.7%, Mn1.5%, Zr1.5%, Cu0.09%, Fe0.13%, and the rest is Al.

[0056] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0057] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0058] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0059] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 3.2MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0060] (4) Screening: The atomized aluminum alloy powder is screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 50%.

[0061] Comparative Example 2

[0062] The difference between this comparative example and Example 1 is: an anodized aluminum alloy powder for laser additive manufacturing, comprising the following components in mass percentage: comprising the following components in mass percentage: Mg3.8%, Mn0.8%, Zr1.1%, Cu0.2%, Fe0.2%, and the rest is Al.

[0063] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0064] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0065] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0066] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 3.2MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0067] (4) Screening: The atomized aluminum alloy powder is screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 47%.

[0068] Comparative Example 3

[0069] The difference between this comparative example and Example 1 is: an anodized aluminum alloy powder for laser additive manufacturing, comprising the following components in mass percentage: comprising the following components in mass percentage: Mg1.8%, Mn1.8%, Zr2.1%, Cu0.24%, Fe0.06%, and the rest is Al.

[0070] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0071] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0072] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0073] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 3.2MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0074] (4) Screening: The atomized aluminum alloy powder is screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 43%.

[0075] Comparative Example 4

[0076] The difference between this comparative example and Example 1 is that the nozzle of the atomization chamber is a multi-hole nozzle.

[0077] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0078] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0079] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0080] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a multi-hole nozzle, the outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 3.2MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0081] (4) Screening: The atomized aluminum alloy powder is screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 40%.

[0082] Comparative Example 5

[0083] The difference between this comparative example and Example 1 is that the air outlet convergence angle is 20°.

[0084] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0085] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0086] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0087] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 20°, the melt superheat is 160°C, the atomization pressure is 3.2MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0088] (4) Screening: The atomized aluminum alloy powder is screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 37%.

[0089] Comparative Example 6

[0090] The difference between this comparative example and Example 1 is that the air outlet convergence angle is 30°.

[0091] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0092] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0093] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0094] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 30°, the melt superheat is 160°C, the atomization pressure is 3.2MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0095] (4) Screening: The atomized aluminum alloy powder is screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 35%.

[0096] Comparative Example 7

[0097] The difference between this comparative example and Example 1 is that the atomization pressure is 2.7 MPa.

[0098] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0099] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0100] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0101] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 2.7MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0102] (4) Screening: The atomized aluminum alloy powder is screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 38%.

[0103] Comparative Example 8

[0104] The difference between this comparative example and Example 1 is that the atomization pressure is 3.6 MPa.

[0105] The method for preparing the above-mentioned anodized aluminum alloy powder for laser additive manufacturing comprises the following steps:

[0106] (1) Weigh the raw materials: prepare the raw materials according to the formula;

[0107] (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon. The smelting conditions are: 810°C, smelting for 22 minutes to obtain molten metal;

[0108] (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; the atomization conditions are: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 3.6MPa, the atomizing gas is high-purity argon, and the atomizing gas temperature is 25°C.

[0109] (4) Screening: The atomized aluminum alloy powder is screened to obtain aluminum alloy powder with a particle size of 15-67 μm, with a yield of 39%.

[0110] Performance Testing

[0111] 1. The aluminum alloy powders prepared in Examples 1-3 and Comparative Examples 1-8 were printed and formed using a selective laser melting (SLM) method. The specific steps are as follows:

[0112] (1) Slice the component model of the required shape with a slice thickness of 0.04 mm. Import the sliced ​​model into the printing parameter software and set the printing parameters. The power of the solid body is 240 W, the scanning speed is 1050 mm / s, the scanning interval is 1.0 mm, the power of the contour body is 210 W, and the scanning speed is 860 mm / s. Fill the set printing parameters into the component model and export the slice file;

[0113] (3) Use a 3D printer to import the slice file into the printer, put the powder into the printer powder bin, place the printing substrate in the molding bin, and start printing using the slice model;

[0114] (4) Open the printer, remove the substrate and the printed aluminum alloy material parts, use a wire cutting machine to cut the substrate and the aluminum alloy material parts, and completely cut off the aluminum alloy material parts along the surface of the substrate;

[0115] (5) Aluminum alloy parts are subjected to solution heat treatment and aging heat treatment, with the solution temperature at 550°C for 2.5 h and the aging temperature at 180°C for 15 h.

[0116] Performance tests were conducted on the above products:

[0117] According to ASTM E8 / E8M standard, the tensile strength, yield strength and elongation are measured.

[0118] A microcomputer-controlled plane thrust wear tester was used to measure the wear amount under the conditions of a test force of 100N, a rotation speed of 200r / min, and dry grinding for 120min at room temperature.

[0119] The results are shown in Table 1.

[0120] 2. Determination of hollow powder ratio of aluminum alloy powder: Refer to GB / T13298-2015 to determine the hollow powder ratio of aluminum alloy powder.

[0121] The results are shown in Table 1.

[0122] 3. The product of Example 1 was subjected to anodizing and color plating. Figure 1 .

[0123] Table 1 Performance test results

[0124]

[0125] It can be seen from the above performance test results that the aluminum alloy powders of Examples 1-3 have excellent performance, especially Example 1 has the most outstanding comprehensive performance, which is mainly due to the synergistic effect of the component ratio and the preparation method.

[0126] However, since the necessary technical solutions were not adopted in the comparative examples, the corresponding performance tests were obviously worse than those of the embodiments. In comparative examples 1-3, the component composition of the aluminum alloy was changed, and it can be seen that the mechanical properties were reduced. In comparative examples 4-8, the atomization method was changed, and it can be seen from the results that the yield of the aluminum alloy powder was affected, and the hollow powder rate was increased. The above experimental results further prove the importance of the technical solution defined in the present invention for its technical effect.

[0127] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An anodized aluminum alloy powder for laser additive manufacturing, characterized in that: It includes the following components in mass percentage: Mg2-5%, Mn0.2-1.5%, Zr0.5-1.5%, Cu0.05-0.20%, Fe0.1-0.2%, and the rest is Al; The mass ratio of Mg, Mn and Zr is (3.6-4.2): (0.3-0.9): (1.0-1.4); The sum of the mass percentages of Cu and Fe ranges from 0.19 to 0.24%.

2. The anodized aluminum alloy powder for laser additive manufacturing according to claim 1, characterized in that: It includes the following components in mass percentage: Mg 3.8%, Mn 0.8%, Zr 1.1%, Cu 0.09%, Fe 0.13%, and the rest is Al.

3. The anodized aluminum alloy powder for laser additive manufacturing according to claim 1, characterized in that: The method for preparing anodized aluminum alloy powder for laser additive manufacturing comprises the following steps: (1) Weigh the raw materials: prepare the raw materials according to the formula; (2) Raw material smelting: Put the raw materials into a smelting crucible and smelt them under the protection of inert gas argon to obtain molten metal; (3) Atomization powder making: The molten metal is atomized under the impact of inert gas to obtain atomized aluminum alloy powder; (4) Screening: Screening the atomized aluminum alloy powder to obtain aluminum alloy powder; The smelting conditions in step (2) are: 790-820° C., 20-25 min; The atomization conditions in step (3) are as follows: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the gas outlet convergence angle is 23-26°, the melt superheat is 150-180°C, the atomization pressure is 3-3.3MPa, the atomization gas is high-purity argon, and the atomization gas temperature is 24-26°C; The aluminum alloy powder having a particle size of 15-67 μm is obtained by sieving in step (4); After screening in step (4), the yield of the aluminum alloy powder is ≥50%.

4. The anodized aluminum alloy powder for laser additive manufacturing according to claim 3, characterized in that: The atomization conditions in step (3) are as follows: the nozzle of the atomization chamber is a hole-slit combined double-cavity nozzle, the gas outlet convergence angle is 25°, the melt superheat is 160°C, the atomization pressure is 3.2 MPa, the atomization gas is high-purity argon, and the atomization gas temperature is 25°C.

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