Additive manufacturing 5-series aluminum alloy powder material containing elements Ce and Yb and preparation method thereof

Abstract

The application discloses additive manufacturing 5-series aluminum alloy powder material containing Ce and Yb elements and a preparation method thereof, and comprises the following steps: preparing a mixed material by weighing raw materials according to component proportions, and preparing Al-Mg-Sc-Yb-Ce-Mn-Si pre-alloy powder through vacuum melting and argon atomization, wherein the raw materials are as follows in terms of mass fraction: Mg: 4-12%, Sc: 0.6-0.8%, Zr: 0.1-0.8%, Mn: 0.2-0.5%, Si: 0.3-1.0%, Yb: 0.03-0.8%, Ce: 0.03-0.8%, and the rest is Al and other impurities. The application adds a certain amount of rare earth elements (Yb and Ce) and Mn and Si elements in the traditional AlMgScZr alloy powder, forms a second phase with alloy elements, plays a role in refining grains and improving crack resistance as a refining agent, controls the process, obtains powder with a certain particle size range through airflow screening, carries out additive manufacturing according to a certain process window, and through heat treatment, the strength of the additive manufacturing high-strength and high-toughness aluminum alloy is improved to 550 MPa level while maintaining high plasticity and toughness.

Description

Technical Field

[0001] This invention belongs to the field of additive manufacturing technology, specifically relating to an additive manufacturing 5-series aluminum alloy powder material containing Ce and Yb elements and its preparation method. Background Technology

[0002] In civil aircraft models, complex aluminum alloy parts such as door hinge arms suffer from problems like dimensional deviations, low yield rates, and long manufacturing cycles when using traditional casting methods. Additive manufacturing of high-strength and high-toughness aluminum alloys, however, can achieve near-net-shape forming, reduce machining workload, significantly shorten manufacturing cycles, and offers the advantage of rapid design iteration. Based on existing material performance data, the material specifications of additively manufactured high-strength and high-toughness aluminum alloys are comparable to those of 7050 and 7075 forgings. Additive manufacturing of high-strength and high-toughness aluminum alloys can be considered as a replacement for traditional aluminum alloy forgings, castings, and machined parts, and can be applied to complex aluminum alloy parts requiring integrated design optimization, thereby reducing the number of parts and assembly time. This has broad potential applications in various aircraft models.

[0003] Existing additive manufacturing high-strength and high-toughness aluminum alloys generally have an Al-Mg-Sc-Zr composition, with strength typically between 450MPa and 500MPa, still lower than 7050 aluminum alloy (maximum approximately 530MPa). This invention adds a certain amount of rare earth elements Ce and Yb to the Al-Mg-Sc-Zr aluminum alloy, primarily acting as a refiner of the reinforcing phase, refining Al3(Sc,Zr) nanoparticles and the grain size of the aluminum alloy matrix. Si and Mn elements in the alloy promote the existence of Ce and Yb in clustered atomic and short-range ordered forms, also primarily acting as refiners of the reinforcing phase, refining Al3(Sc,Zr) nanoparticles and the grain size of the aluminum alloy matrix. This significantly delays fatigue crack initiation, improves fracture toughness, increases tensile strength to the 550MPa level, and maintains an elongation at break of no less than 10%, substantially enhancing the alloy's overall static and dynamic mechanical properties to meet aerospace applications. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0005] In view of the problems existing in the above and / or prior art, the present invention is proposed.

[0006] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide an additive manufacturing 5-series aluminum alloy powder material containing Ce and Yb elements and its preparation method.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: elements Mg, Sc, Zr, Mn, Si, Yb, Ce, and Al: wherein,

[0008] The content of Mg is 4-12% by mass fraction, the content of Sc is 0.6-0.8%, the content of Zr is 0.1-0.8%, the content of Mn is 0.2-0.5%, the content of Si is 0.3-1.0%, the content of Yb is 0.03-0.8%, the content of Ce is 0.03-0.8%, and the remainder is Al and other impurities.

[0009] As a preferred embodiment of the preparation method described in this invention, the additively manufactured 5-series aluminum alloy powder material is composed of the following components by mass fraction: Mg: 6.5%, Sc: 0.60%, Zr: 0.42%, Mn: 0.50%, Si: 0.90%, Yb: 0.05%, Ce: 0.08%, with the remainder being Al.

[0010] As a preferred embodiment of the preparation method described in this invention, the additively manufactured 5-series aluminum alloy powder material has the following characteristics:

[0011] (a) Density not less than 98%;

[0012] (b) The typical value of tensile strength is not less than 550 MPa, the typical value of yield strength is not less than 500 MPa, and the tensile strength S value is not less than 540 MPa;

[0013] (c) The coefficient of variation of tensile strength (CV) is not higher than 2%, the elongation at break is not lower than 10%, and the hardness is not lower than 160HV;

[0014] (d) The powder particle size is 15-135μm, the loose powder density is not less than 1.3g / cm3, the tapped density is not less than 1.6g / cm3, and the sphericity is not less than 85%.

[0015] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing additive manufacturing 5-series aluminum alloy powder materials containing Ce and Yb elements.

[0016] As a preferred embodiment of the preparation method described in this invention, wherein:

[0017] Powder formulation design: Weigh the component elements or intermediate alloy and prepare a mixture;

[0018] Tool purification: Coat all stirring tools with titanium dioxide to prevent impurities from entering; dry crucibles and other tools to ensure a dry powder-making environment;

[0019] Vacuum melting: The above mixed powders are melted under vacuum;

[0020] Atomization powder production: Argon gas is used as a medium to atomize the smelted alloy;

[0021] Sieving: The prepared powder is sieved.

[0022] Heat preservation and drying: The sieved powder is kept at a heat preservation temperature and dried.

[0023] As a preferred embodiment of the preparation method described in this invention, the vacuum melting process involves first evacuating the vacuum to 10... -2 Within Pa, the melting temperature is 700-1000℃, and argon gas is then introduced to a slightly positive pressure, with the gas pressure inside the melting furnace being 0.55-0.7MPa.

[0024] In a preferred embodiment of the preparation method described in this invention, the atomization powdering is performed using argon gas, with an atomization pressure of 5–7.5 MPa and a gas flow rate of 2–5 mL / min.

[0025] As a preferred embodiment of the preparation method described in this invention, the heat preservation and drying temperature is 80-120℃, and the heat preservation time is 3-8 hours.

[0026] Another objective of this invention is to overcome the shortcomings of the prior art and provide an application of additive manufacturing 5-series aluminum alloy powder materials containing Ce and Yb elements in the aerospace field.

[0027] As a preferred embodiment of the preparation method described in this invention, wherein:

[0028] Set the laser scanning path and parameters; the substrate preheating temperature is 90–120℃, and the powder layer thickness is 0.03–0.06 mm; for the initial 1–10 layers, the laser scanning power is 210–380 W, the scanning speed is 700–1100 mm / s, and each layer is scanned twice; for the internal solids of the intermediate layers, the laser scanning power is 200–400 W, the scanning speed is 800–1200 mm / s, the scanning interval is 0.05–0.2 mm, and the interlayer angle is 67°; for the outer contours of the intermediate layers, the laser scanning power is 180–380 W, and the scanning speed is 600–1500 mm / s; for the final 1–10 layers, the laser scanning power is 180–400 W, the scanning speed is 600–1500 mm / s, and each layer is scanned twice.

[0029] As a preferred embodiment of the preparation method described in this invention, after printing, the sample and substrate are placed in a vacuum furnace for stress-relief annealing and then aging treatment. The stress-relief annealing temperature is 150-200°C, the holding time is 3-10 hours, and the cooling method is air cooling.

[0030] As a preferred embodiment of the preparation method described in this invention, the aging treatment temperature is 300-350°C, vacuum or argon protection is used, the holding time is 2-10 hours, and the cooling method is furnace cooling.

[0031] Beneficial effects of this invention:

[0032] (1) The present invention adds a certain amount of rare earth elements Yb and Ce to the Al-Mg-Sc-Zr aluminum alloy. Among them, Yb can form Al3(Zr,Yb) phase with alloying elements, which serves as a non-uniform nucleation site to refine the grains. In addition, the Al3(Zr,Yb) phase is dispersed and can pin dislocations to improve performance.

[0033] (2) In this invention, Ce element is used to increase the supercooling of alloy composition, reduce gas and inclusions in the alloy, and make the inclusions tend to spheroidize, form metastable phase with Al and Mn elements, refine grains, reduce crack sensitivity, and consume Fe impurities in the alloy, thereby increasing the stability of the alloy.

[0034] (3) In the alloy of this invention, the role of Si and Mn elements is to promote the existence of Yb and Ce elements in the form of clustered atoms and short-range order. Their main function is to act as a phase refiner, that is, to refine Al3(Sc,Zr) nanoparticles and also to refine the grain size of the aluminum alloy matrix. It can delay the initiation of fatigue cracks, improve fracture toughness, increase tensile strength to the 550MPa level while maintaining high toughness and elongation, and significantly improve the overall static and dynamic mechanical properties of the alloy to meet the needs of aerospace applications. In addition, Sc element is expensive, and replacing part of Sc element with Yb can reduce the cost of the alloy while ensuring the strength and toughness of the material.

[0035] (4) This invention discloses a powder preparation process that is compatible with this aluminum alloy powder material, including tool impurity removal, vacuum melting, atomization powder making, sieving, heat preservation and drying and other processes, and specifies the range of powder making process parameters, so as to maximize the uniform alloying, purification, less burning loss and improved melting efficiency of the melting process.

[0036] (5) The present invention discloses the printing and heat treatment process parameters that are compatible with this aluminum alloy powder material, so that the density of the formed part is not less than 98%, the typical value of tensile strength is not less than 550MPa, the typical value of yield strength is not less than 500MPa, the tensile strength S value is not less than 540MPa, the coefficient of variation CV value is not higher than 2%, the elongation at break is not less than 10%, and the hardness is not less than 160HV, which can meet the application requirements of aerospace for high strength and toughness aluminum alloy materials. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0038] Figure 1 The images shown are powder morphology diagrams for Examples 1 to 3 of the present invention, where (a) is Example 1; (b) is Example 2; and (c) is Example 3.

[0039] Figure 2 The following are metallographic diagrams of Examples 1 to 3 of the present invention, wherein (a) is Example 1; (b) is Example 2; and (c) is Example 3.

[0040] Figure 3 This is the fatigue SN curve of Embodiment 1 of the present invention.

[0041] Figure 4 This is the fatigue SN curve of Embodiment 2 of the present invention.

[0042] Figure 5 This is the fatigue SN curve of Embodiment 3 of the present invention. Detailed Implementation

[0043] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0044] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0045] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0046] Example 1

[0047] The aerospace lightweight high-strength Al-Mg-Sc-Zr-Yb-Ce-Mn-Si alloy composition described in this invention comprises, by mass fraction, the following components: Mg: 4%, Sc: 0.6%, Zr: 0.3%, Mn: 0.2%, Si: 0.6%, Yb: 0.1%, Ce: 0.1%, with the remainder being Al.

[0048] The preparation method of the above alloy powder is as follows:

[0049] (1) Vacuum melting: Weigh the metal blocks according to the proportions of each element and place them in a vacuum induction furnace for heating and melting into a pre-alloy; first, evacuate to 100°C. -2 Within Pa, the melting temperature is 700℃, and argon gas is then introduced to a slightly positive pressure, with the gas pressure inside the melting furnace being 0.6MPa; the atomization powdering uses argon gas, with an atomization pressure of 6MPa and a gas flow rate of 3mL / min;

[0050] (2) Atomization powder making: The above pre-alloyed material is transferred into an atomization tank and powder is made using argon gas.

[0051] (3) Airflow sieving: The powder obtained in the previous step is sieved through airflow to obtain powders with different particle size ranges;

[0052] (4) Heat preservation and drying: Place the sieved powder into a drying oven and heat preservation for 4 hours at a temperature of 100℃. The powder morphology is as follows: Figure 1 As shown in (a). Powder properties are shown in Table 1. Powder particle size distribution is shown in Table 2. The vast majority of powder particles are between 15-60 μm in size, which is suitable for selective laser melting in powder beds.

[0053] The laser parameters for 3D printing with the above powder are as follows: substrate preheating temperature is 90℃, powder layer thickness is 0.06mm; for the initial 1-10 layers, the laser scanning power is 210W, the scanning speed is 700mm / s, and each layer is scanned twice; for the internal solids of the middle layers, the laser scanning power is 400W, the scanning speed is 1200mm / s, the scanning interval is 0.05mm, and the interlayer angle is 67°; for the outer contours of the middle layers, the laser scanning power is 180W, and the scanning speed is 600mm / s; for the last 1-10 layers, the laser scanning power is 180W, the scanning speed is 600mm / s, and each layer is scanned twice.

[0054] Heat treatment: stress-relief annealing at 150℃ for 10 hours, air cooling; aging treatment at 300℃ under argon protection for 10 hours, furnace cooling; the resulting material's microstructure is as follows. Figure 2 As shown in (a), the microstructure is uniform and crack-free. The mechanical properties of the alloy were tested, and the results are shown in Tables 3 and 4. The density is 99.8%, the tensile strength is 572 MPa, the yield strength is 550 MPa, the elongation at break is 13.1%, the hardness (HV) is 173, the S value is 551.1 MPa, and the CV value is 0.9%. The fracture toughness of the alloy was tested, and the results are shown in Table 5. The fracture toughness K1C = 32.62 MPa / m. 1 / 2The fatigue properties of the alloy were tested, and the alloy fatigue SN curve is shown below. Figure 3 As shown, the fatigue limit strength of the alloy at Kt=1 and R=-1 is 150MPa.

[0055] Example 2

[0056] The aerospace lightweight high-strength Al-Mg-Sc-Zr-Yb-Ce-Mn-Si alloy composition described in this invention comprises, by mass fraction, the following components: Mg: 6%, Sc: 0.7%, Zr: 0.6%, Mn: 0.4%, Si: 0.7%, Yb: 0.8%, Ce: 0.8%, with the remainder being Al.

[0057] The preparation method of the above alloy powder is as follows:

[0058] (1) Vacuum melting: Weigh the metal blocks according to the proportions of each element and place them in a vacuum induction furnace for heating and melting into a pre-alloy; first, evacuate to 100°C. -2 Within Pa, the melting temperature is 900℃, and argon gas is then introduced to a slightly positive pressure, with the gas pressure inside the melting furnace being 0.55MPa; the atomization powdering uses argon gas, with an atomization pressure of 5MPa and a gas flow rate of 2mL / min;

[0059] (2) Atomization powder making: The above pre-alloyed material is transferred into an atomization tank and powder is made using argon gas.

[0060] (3) Mechanical sieving: The above pre-alloyed powder is subjected to sieve treatment to obtain metal powder with a particle size range of 15 to 63 μm.

[0061] (4) Heat preservation and drying: Place the sieved powder into a drying oven and heat preservation for 8 hours at a temperature of 80℃. The powder morphology is as follows: Figure 1 (b) shows the powder properties, as shown in Table 1. The powder particle size distribution is shown in Table 2.

[0062] The laser parameters for 3D printing with the above powder are as follows: substrate preheating temperature is 120℃, powder layer thickness is 0.03mm; for the initial 1-10 layers, the laser scanning power is 250W, the scanning speed is 850mm / s, and each layer is scanned twice; for the internal solids of the middle layers, the laser scanning power is 200W, the scanning speed is 800mm / s, the scanning interval is 0.2mm, and the interlayer rotation angle is 67°; for the outer contour of the middle layers, the laser scanning power is 250W, and the scanning speed is 1000mm / s; for the last 1-10 layers, the laser scanning power is 400W, the scanning speed is 1500mm / s, and each layer is scanned twice.

[0063] Heat treatment: stress-relief annealing at 200℃ for 3 hours, air cooling; aging treatment at 350℃ under argon protection for 2 hours, furnace cooling; the resulting material's microstructure is as follows. Figure 2 As shown in (b), the microstructure is uniform and crack-free. The mechanical properties of the alloy were tested, and the results are shown in Tables 3 and 4. The density is 99.9%, the tensile strength is 571 MPa, the yield strength is 548 MPa, the elongation at break is 13%, the hardness (HV) is 170, the S value is 548.2 MPa, and the CV value is 1.0%. The fracture toughness of the alloy was tested, and the results are shown in Table 5. The fracture toughness K1C = 31.89 MPa / m. 1 / 2 The fatigue properties of the alloy were tested, and the alloy fatigue SN curve is shown below. Figure 4 As shown, the fatigue limit strength of the alloy at Kt=1 and R=0.5 is 290MPa.

[0064] Example 3

[0065] The aerospace lightweight high-strength Al-Mg-Sc-Zr-Yb-Ce-Mn-Si alloy composition of this invention comprises, by mass fraction, the following components: Mg: 6.5%, Sc: 0.60%, Zr: 0.42%, Mn: 0.50%, Si: 0.90%, Yb: 0.05%, Ce: 0.08%, with the remainder being Al.

[0066] The preparation method of the above alloy powder is as follows:

[0067] (1) Vacuum melting: Weigh the metal blocks according to the proportions of each element and place them in a vacuum induction furnace for heating and melting into a pre-alloy; first, evacuate to 100°C. -2 Within Pa, the melting temperature is 1000℃, and argon gas is then introduced to a slightly positive pressure, with the gas pressure inside the melting furnace being 0.7MPa; the atomization powdering uses argon gas, with an atomization pressure of 7.5MPa and a gas flow rate of 5mL / min;

[0068] (2) Atomization powder making: The above pre-alloyed material is transferred into an atomization tank and powder is made using argon gas.

[0069] (3) Mechanical sieving: The above pre-alloyed powder is subjected to sieve treatment to obtain metal powder with a particle size range of 15 to 60 μm.

[0070] (4) Heat preservation and drying: Place the sieved powder into a drying oven and heat preservation for 3 hours at a temperature of 120℃. The powder morphology is as follows: Figure 1 (c) shows the powder properties, as shown in Table 1. The powder particle size distribution is shown in Table 2.

[0071] The laser parameters for 3D printing with the above powder are as follows: substrate preheating temperature is 100℃, powder layer thickness is 0.03mm; for the initial 1-10 layers, the laser scanning power is 380W, scanning speed is 1100mm / s, and each layer is scanned twice; for the internal solids of the intermediate layers, the laser scanning power is 330W, scanning speed is 1000mm / s, scanning spacing is 0.12mm, and interlayer rotation angle is 67°; for the outer contours of the intermediate layers, the laser scanning power is 380W, scanning speed is 1500mm / s; for the final 1-10 layers, the laser scanning power is 250W, scanning speed is 1000mm / s, and each layer is scanned twice. Heat treatment is performed as follows: stress-relief annealing temperature is 170℃, holding time is 5h, and cooling method is air cooling; aging treatment temperature is 325℃, using vacuum protection, holding time is 4h, and cooling method is furnace cooling; the resulting alloy microstructure is as follows. Figure 5 As shown, the microstructure is uniform and free of cracks and pores. The mechanical properties of the alloy were tested, and the results are shown in Tables 3 and 4. The density is 99.9%, the tensile strength is 578 MPa, the yield strength is 555 MPa, the elongation at break is 14.9%, the hardness (HV) is 175, the S value is 556.5 MPa, and the CV value is 0.8%. The fracture toughness of the alloy was tested, and the results are shown in Table 5. The fracture toughness K1C = 33.90 MPa / m. 1 / 2 The fatigue properties of the alloy were tested, and the alloy fatigue SN curve is shown below. Figure 5 As shown, the fatigue limit strength of the alloy at Kt=1 and R=0.1 is 220MPa.

[0072] Table 1. Powder properties in Examples 1-3

[0073]

[0074] As can be seen from Table 1, the loose bulk density of the powders prepared in Examples 1-3 is not less than 1.3 g / cm³. 3 The tapped density is not less than 1.6 g / cm³. 3 A sphericity of not less than 85% means that the powder has good flowability, which is beneficial to the selective laser melting and forming process.

[0075] Table 2. Powder particle size distribution in Examples 1-3

[0076]

[0077] As can be seen from Table 2, the particle size distribution range of Examples 1 to 3 is suitable, and the ratio of ultrafine powder to coarse powder is good, which is beneficial to the selective laser melting forming process.

[0078] Table 3. Statistical table of average tensile properties in Examples 1-3

[0079]

[0080]

[0081] As can be seen from Table 3, the density of Examples 1 to 3 is not less than 98%, the typical value of tensile strength is not less than 550 MPa, the typical value of yield strength is not less than 500 MPa, the elongation at break is not less than 10%, and the hardness is not less than 160 HV, which are high-strength, high-toughness and high-ductility aluminum alloys.

[0082] Table 4. Statistical table of room temperature tensile strength S-value and CV-value in Examples 1-3

[0083]

[0084] As can be seen from Table 4, the tensile strength S value of Examples 1 to 3 is not less than 540 MPa, and the coefficient of variation CV value is not higher than 2%, which meets the data dispersion requirements of aerospace products for metallic materials and the performance requirements of high strength and toughness aluminum alloy materials, and has high stability and reliability.

[0085] Table 5 Fracture toughness in Examples 1-3

[0086]

[0087] As can be seen from Table 5, the fracture toughness K1C of Examples 1 to 3 is not less than 31 MPa. 1 / 2 The material exhibits good damage tolerance and superior resistance to crack initiation and propagation.

[0088] Comparative Example 1

[0089] The difference from Example 3 is that the substrate preheating temperature is 80°C, the internal solid laser power is 150W, the scanning speed is 750mm / s, the layer thickness is 0.01mm, the scanning spacing is 0.03mm, and the interlayer rotation angle is 45°. The external contour laser power is 160W, the scanning speed is 500mm / s, and the printing parameters for the starting and ending layers are the same as those for the intermediate layers.

[0090] Comparative Example 2

[0091] The difference from Example 3 is that the substrate preheating temperature is 130°C, the internal solid laser power is 420W, the scanning speed is 1250mm / s, the layer thickness is 0.06mm, the scanning spacing is 0.23mm, there is no printing deflection angle between layers, the external contour laser power is 400W, the scanning speed is 1600mm / s, and the printing parameters of the printing start layer and the printing end layer are the same as those of the intermediate layer.

[0092] Comparative Example 3

[0093] The difference from Example 3 is that the stress-relief annealing temperature is 140°C and the holding time is 11 hours, while the aging treatment temperature is 250°C and the holding time is 12 hours.

[0094] Comparative Example 4

[0095] The difference from Example 3 is that the stress-relief annealing temperature is 210°C and the holding time is 2 hours, and the aging treatment temperature is 360°C and the holding time is 2 hours.

[0096] Comparative Example 5

[0097] The difference from Example 3 is that the Ce content is 0.

[0098] Comparative Example 6

[0099] The difference from Example 3 is that the Yb content is 0.

[0100] Comparative Example 7

[0101] The difference from Example 3 is that the Ce content is 0 and the Yb content is 0.

[0102] Table 6. Statistical table of average tensile properties of comparative examples 1-7

[0103]

[0104]

[0105] Table 7 Fracture toughness of Comparative Examples 1–7

[0106]

[0107] As shown in Tables 7 and 8, compared with Example 3, the unit laser energy density of Comparative Example 1 is too high, and some low-melting-point elements in the powder, such as Mg, are prone to vaporization. The vaporization back pressure can cause the liquid metal in the molten pool to splash, easily producing defects such as pores. On the other hand, the unit laser energy density of Comparative Example 2 is too low, easily producing defects such as incomplete fusion and poor fusion. Therefore, the performance of Comparative Examples 1 and 2 is lower than that of the Example 3. Compared with Example 3, the heat treatment temperature of Comparative Example 3 is too low, failing to reach the aging temperature, and only a small amount of solute atoms are dissolved. On the other hand, the heat treatment temperature of Comparative Example 4 is too high, leading to the growth of precipitated phases and a decrease in strength. Therefore, the performance of Comparative Examples 3 and 4 is also lower. Compared to Example 3, Comparative Examples 5, 6, and 7 lack Ce, Yb, and both elements, respectively. Ce increases alloy supercooling, which not only refines the second-phase particles but also consumes Fe impurities in the alloy, improving its corrosion resistance and stability. Yb can form Al3(Zr,Yb) phase coherent with Zr and Al in the alloy, serving as non-uniform nucleation sites and refining the grains. The secondary Al3(Zr,Yb) phase is dispersed throughout the material, pinning dislocations and other defects, thus improving the material's mechanical properties. Therefore, the performance of Comparative Examples 5, 6, and 7 is lower than that of Example 3.

[0108] This invention adds a certain amount of rare earth elements (Yb, Ce) as well as Mn and Si to traditional AlMgScZr alloy powder. These elements form a second phase with the alloying elements, acting as grain refiners to improve grain size and crack resistance. By controlling the process, powder with a specific particle size range is obtained through airflow sieving. Additive manufacturing is then performed according to a defined process window, followed by heat treatment. This process increases the strength of the additively manufactured high-strength and high-toughness aluminum alloy to the 550 MPa level while maintaining high ductility and toughness. Furthermore, the high price of Sc element keeps the price of existing high-strength aluminum alloy powders high, while Yb is much cheaper. Replacing some Sc elements with Yb can reduce the cost of the alloy.

[0109] The additive manufacturing 5-series aluminum alloy powder material containing Ce and Yb elements provided by this invention is formed by adding Sc element and Al to generate Al3Sc phase. The fine Al3Sc particles are dispersed in the matrix, resulting in non-uniform nucleation, which can effectively inhibit recrystallization and improve the strength and toughness of the alloy. The Al3Sc precipitate phase can also effectively pin the grain boundaries and has age hardening characteristics.

[0110] Zr reacts with Al to form the desolvated Al3Zr phase, and can also form Al3(Sc,Zr) with Al3Sc. Both Al3Sc and Al3(Sc,Zr) are coherent with the Al matrix and act as heterogeneous nucleating agents. At the same time, they can reduce the surface tension of the liquid metal, reduce the critical nucleation work, refine the grains, and thus significantly reduce the formation of defects such as cracks, thereby enhancing the strength and toughness of the alloy.

[0111] Ce acts as an element to increase alloy supercooling, reduce gases and inclusions in the alloy, and promote the spheroidization of inclusions. Together with Mg, Ce can also stimulate the modification effects of rare earth elements, improving the overall properties of the alloy. Ce can also form Al-Al11Ce3 symbiotic phases and metastable Al phases. 20 Mn2Ce, where Al-Al 11 The Ce3 symbiotic phase has a similar crystal structure to α-Al and can serve as heterogeneous nucleation sites during solidification, thereby refining the grain size; the metastable Al phase... 20 Mn2Ce can effectively refine grains, reduce crack susceptibility, and improve the corrosion resistance of the alloy. The addition of Ce not only refines the second-phase particles but also consumes Fe impurities in the alloy, transforming Al3Fe and Al6Fe into the stable Al3Fe3Ce phase, thereby improving the corrosion resistance and stability of the alloy.

[0112] The role of Yb is to form the Al3(Zr,Yb) phase, coherent with the Al matrix, with Zr and Al in the alloy. Similar to Al3(Sc,Zr), the primary Al3(Zr,Yb) phase serves as an excellent heterogeneous nucleation site, refining grains and significantly improving the material's microstructure. Meanwhile, the secondary Al3(Zr,Yb) phase, dispersed throughout the material, can pin dislocations and other defects, enhancing the material's mechanical properties.

[0113] The role of Mn and Si is to promote the precipitation of Ce and Yb particles, and to ensure that Ce and Yb exist in the form of cluster atoms and short-range ordered forms, which can delay the initiation of fatigue cracks.

[0114] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the present invention.

Claims

1. An additive manufacturing 5-series aluminum alloy powder material containing Ce and Yb elements, characterized in that: include, Elements Mg, Sc, Zr, Mn, Si, Yb, Ce, and Al: where, The content of Mg is 4-12% by mass fraction, the content of Sc is 0.6-0.8%, the content of Zr is 0.1-0.8%, the content of Mn is 0.2-0.5%, the content of Si is 0.3-1.0%, the content of Yb is 0.03-0.8%, the content of Ce is 0.03-0.8%, and the remainder is Al and other impurities.

2. The additive manufacturing 5-series aluminum alloy powder material as described in claim 1, characterized in that: The additive manufacturing 5-series aluminum alloy powder material, by mass fraction, consists of the following components: Mg: 6.5%, Sc: 0.60%, Zr: 0.42%, Mn: 0.50%, Si: 0.90%, Yb: 0.05%, Ce: 0.08%, with the remainder being Al.

3. The additive manufacturing 5-series aluminum alloy powder material as described in claim 1, characterized in that: The additively manufactured 5-series aluminum alloy powder material has the following characteristics: (a) Density not less than 98%; (b) The typical value of tensile strength is not less than 550 MPa, the typical value of yield strength is not less than 500 MPa, and the tensile strength S value is not less than 540 MPa; (c) The coefficient of variation of tensile strength (CV) is not higher than 2%, the elongation at break is not lower than 10%, and the hardness is not lower than 160HV; (d) The powder particle size is 15–135 μm, and the loose powder density is not less than 1.3 g / cm³. 3 The tapped density is not less than 1.6 g / cm³. 3 The sphericity is not less than 85%.

4. The method for preparing additively manufactured 5-series aluminum alloy powder material according to any one of claims 1 to 3, characterized in that: include, Powder formulation design: Weigh the component elements or intermediate alloy and prepare a mixture; Tool purification: Coat all stirring tools with titanium dioxide to prevent impurities from entering; dry crucibles and other tools to ensure a dry powder-making environment; Vacuum melting: The above mixture is melted under vacuum; Atomization powder production: Argon gas is used as a medium to atomize the smelted alloy; Sieving: The prepared powder is sieved. Heat preservation and drying: The sieved powder is kept at a heat preservation temperature and dried.

5. The preparation method according to claim 4, characterized in that: The vacuum melting process involves first evacuating the vacuum to 10... -2 Within Pa, the melting temperature is 700-1000℃, and argon gas is then introduced to a slightly positive pressure, with the gas pressure inside the melting furnace being 0.55-0.7MPa.

6. The preparation method according to claim 4, characterized in that: The atomization powder preparation uses argon gas, with an atomization pressure of 5–7.5 MPa and a gas flow rate of 2–5 mL / min.

7. The preparation method according to claim 4, characterized in that: The heat preservation and drying temperature is 80-120℃, and the heat preservation time is 3-8 hours.

8. The application of the additive manufacturing 5-series aluminum alloy powder material containing Ce and Yb elements as described in claim 1 in the aerospace field, characterized in that: include, Set the laser scanning path and parameters; the substrate preheating temperature is 90–120℃, and the powder layer thickness is 0.03–0.06 mm; for the initial printing layers 1–10, the laser scanning power is 210–380 W, the scanning speed is 700–1100 mm / s, and each layer is scanned twice; for printing the internal solids of the intermediate layers, the laser scanning power is 200–400 W, the scanning speed is 800–1200 mm / s, the scanning interval is 0.05–0.2 mm, and the interlayer rotation angle is 67°; for printing the outer contour of the intermediate layers, the laser scanning power is 180–380 W, and the scanning speed is 600–1500 mm / s. For layers 1-10 near the end of printing, the laser scanning power is 180-400W, the scanning speed is 600-1500mm / s, and each layer is scanned twice by laser.

9. The application as described in claim 8, characterized in that: After printing, the sample, along with the substrate, is placed in a vacuum furnace for stress-relief annealing and then aging treatment. The stress-relief annealing temperature is 150-200℃, the holding time is 3-10h, and the cooling method is air cooling.

10. The application as described in claim 9, characterized in that: The aging treatment temperature is 300-350℃, with vacuum or argon protection, and the holding time is 2-10 hours. The cooling method is furnace cooling.

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