High-performance and high-temperature-resistant aluminum alloy and preparation method thereof

Abstract

According to the high-performance and high-temperature-resistant aluminum alloy and the preparation method thereof, an Al-Mg-Mn-Cu-Sr alloy serves as a base body of the heat-resistant and high-strength aluminum alloy material, microalloying elements are properly added, the heat-resistant and high-strength aluminum alloy material has good mechanical performance at the room temperature, the high temperature of 250 DEG C and the high temperature of 300 DEG C, and an aluminum alloy product is free of holes and tiny cracks. And the use requirements of the high-temperature-resistant aluminum alloy in the fields of aerospace, traffic transportation, oil exploration, high-voltage power transmission, nuclear fuel storage and the like can be met.

Description

Technical Field

[0001] The invention relates to a high-performance, high-temperature resistant aluminum alloy and a preparation method thereof, belonging to the technical field of aluminum alloy materials. Background Art

[0002] In recent years, the continuous development of economy and society has also put forward higher requirements on the heat resistance of aluminum alloys. For example, the temperature generated by the friction between the surface and the atmosphere of an ordinary aircraft during flight can reach more than 160°C, and the local temperature can even reach 200°C. In addition, in transportation, oil exploration, high-voltage power transmission, nuclear fuel storage and other fields, higher requirements are also put forward on the heat resistance of aluminum alloys.

[0003] Heat-resistant aluminum alloy refers to an aluminum alloy that has sufficient oxidation resistance and good mechanical properties at high temperatures of 150 to 350°C, and has good creep resistance under long-term action of certain temperature and load. Heat-resistant aluminum alloys are widely used in my country. According to the processing method, they can be divided into cast heat-resistant aluminum alloys, deformed heat-resistant aluminum alloys, and powder metallurgy heat-resistant aluminum alloys. Components represented by cast heat-resistant alloys are mainly used in internal combustion engines, automobile engine cylinders, and aircraft engines. With the increase in the requirements for high power density and fuel economy of power systems, the upper temperature limit of heat-resistant aluminum alloys for local components has been increased from the traditional 250°C to above 300 to 400°C. Therefore, it is of great significance to carry out research on high-performance and high-temperature resistant aluminum alloys.

[0004] CN119351833A uses 3.12-5.34% nickel, 4.24-6.76% molybdenum, 6.54-8.12% cobalt, 10.45-14.49% silicon, 5.65-8.45% functional additives, 1.25-2.45% cerium oxide, 3.46-7.42% yttrium oxide, 3.45-7.58% lanthanum oxide, and the balance aluminum. The alloy composition used has high Ni, Mo, and Co content, and also contains more rare earth elements, and the production cost is relatively high.

[0005] CN119265458A uses Cu 3.5wt%, Si 8.8wt%, Zn 0.65%, Mn 0.10wt%, Mg 0.48wt%, Fe 0.19wt%, Sr 0.023wt%, Mo 0.128%, W 0.085wt%, V 0.052wt%, and the remainder is Al and impurities, wherein the total impurity content is not more than 0.25wt%, (2.0Zn+1.5Mg+0.5Cu) is 3.77, the ratio of 10(Mo-W) / Si element mass fraction is 0.049, and the ratio of Fe / V element mass fraction is 3.65. The main room temperature mechanical properties of the standard specimens tested are as follows: tensile strength 476MPa, yield strength 397MPa, elongation after fracture 2.6%, hardness 147HB; (250℃) high temperature mechanical properties are as follows: tensile strength 285MPa, yield strength 235MPa, elongation after fracture 5.2%, hardness 94HB. The raw materials used are relatively inexpensive, but the mechanical properties at high temperatures may not be suitable for use above 250, 300℃.

[0006] Traditional heat-resistant aluminum alloys, such as 2XXX series alloys and Al-Fe series alloys, have a heat-resistant temperature that is difficult to exceed 300°C. Therefore, it is necessary to develop a suitable high-performance, high-temperature resistant aluminum alloy and its preparation method for more demanding high-temperature resistant application scenarios. Summary of the invention

[0007] In order to improve the current situation that the same type of aluminum alloy cannot meet the needs of additive manufacturing technology and overcome the insufficient mechanical properties of aluminum alloy materials under high temperature conditions, the present invention provides a high-performance, high-temperature resistant aluminum alloy and its preparation method. The heat-resistant and high-strength aluminum alloy material is based on Al-Mg-Mn-Cu-Sr alloy, and micro-alloying elements Be and rare earth elements Ce are appropriately added. It has good mechanical properties (such as tensile strength and yield strength) and ductility at room temperature, 250°C, and 300°C high temperature, and the aluminum alloy products have no holes and micro cracks. It can meet the use requirements of high-temperature resistant aluminum alloys in multiple fields such as aerospace, transportation, oil exploration, high-voltage power transmission, and nuclear fuel storage.

[0008] The object of the present invention is achieved through the following technical solutions:

[0009] A high-performance, high-temperature resistant aluminum alloy, wherein the high-performance, high-temperature resistant aluminum alloy material is calculated by mass percentage as follows: Mg: 6.1-7%, Mn: 2.1-2.5%, Cu: 1.7-1.9%, Sr: 0.4-0.5%, Be: 0.05-0.10%, rare earth Ce: 0.01-0.03%, Fe≤0.05wt%, C≤0.01wt%, H≤0.015wt%, O≤0.05wt%, N≤0.02wt%, impurity elements≤0.2%, and the balance is aluminum.

[0010] Furthermore, the high-performance, high-temperature resistant aluminum alloy, wherein:

[0011] After batching, smelting, atomization powder making, molding, heat treatment and surface treatment,

[0012] At room temperature: the yield strength of aluminum alloy is 520-560MPa, the tensile strength is 580-640MPa, and the elongation is greater than 10%;

[0013] At 250℃, the yield strength of aluminum alloy is 260-300MPa, the tensile strength is 330-380MPa, and the elongation is greater than 16%;

[0014] At 300℃, the yield strength of aluminum alloy is 220-250MPa, the tensile strength is 300-330MPa, and the elongation is greater than 18%;

[0015] Furthermore, the high-performance, high-temperature resistant aluminum alloy, wherein:

[0016] The high-performance, high-temperature resistant aluminum alloy material is composed of Mg: 6.3-6.7%, Mn: 2.2-2.4%, Cu: 1.75-1.85%, Sr: 0.45-0.5%, Be: 0.07-0.09%, rare earth Ce: 0.015-0.025%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0017] Alternatively, the high-performance, high-temperature resistant aluminum alloy material is, by mass percentage, Mg: 6.1%, Mn: 2.5%, Cu: 1.9%, Sr: 0.4%, Be: 0.05%, rare earth Ce: 0.01%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0018] Alternatively, the high-performance, high-temperature resistant aluminum alloy material is, by mass percentage, Mg: 6.3%, Mn: 2.4%, Cu: 1.8%, Sr: 0.45%, Be: 0.07%, rare earth Ce: 0.015%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0019] Alternatively, the high-performance, high-temperature resistant aluminum alloy material is, by mass percentage, Mg: 6.5%, Mn: 2.3%, Cu: 1.8%, Sr: 0.45%, Be: 0.08%, rare earth Ce: 0.02%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0020] Alternatively, the high-performance, high-temperature resistant aluminum alloy material is, by mass percentage, Mg: 6.7%, Mn: 2.2%, Cu: 1.7%, Sr: 0.5%, Be: 0.085%, rare earth Ce: 0.02%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0021] Alternatively, the high-performance, high-temperature resistant aluminum alloy material is, by mass percentage, Mg: 6.9%, Mn: 2.15%, Cu: 1.75%, Sr: 0.45%, Be: 0.09%, rare earth Ce: 0.025%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0022] Alternatively, the high-performance, high-temperature resistant aluminum alloy material is, by mass percentage, Mg: 7%, Mn: 2.1%, Cu: 1.85%, Sr: 0.4%, Be: 0.1%, rare earth Ce: 0.03%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0023] Furthermore, the preparation method of the high-performance, high-temperature resistant aluminum alloy comprises the following steps:

[0024] (1) Batching: Weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product;

[0025] (2) Melting: preheating and drying the prepared alloy raw materials, and then melting them to obtain aluminum alloy liquid;

[0026] (3) Atomization powder making: Control the melting temperature, input the aluminum alloy liquid into the tundish, and prepare aluminum alloy powder by atomization;

[0027] (4) Molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0028] (5) Heat treatment: heat treatment of the aluminum alloy products after forming;

[0029] (6) Surface treatment: Surface treatment is performed on the aluminum alloy products after heat treatment.

[0030] Furthermore, the preparation method of the high-performance, high-temperature resistant aluminum alloy comprises the following steps:

[0031] Step (1) batching: weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product;

[0032] The raw materials include aluminum ingots with aluminum content ≥99.7%, magnesium ingots with magnesium content ≥99.7%, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy.

[0033] Furthermore, the preparation method of the high-performance, high-temperature resistant aluminum alloy comprises the following steps:

[0034] Step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid;

[0035] The aluminum ingot is heated and melted at 720-730°C, and the temperature is gradually raised to 730-780°C at a heating rate of 5-10°C / min. During the heating process, magnesium ingots, AlMn10 master alloys, AlCu50A master alloys, AlSr10 master alloys, AlBe3 master alloys, and AlCe10 master alloys are added, and the mixture is stirred and melted into aluminum alloy liquid. The aluminum alloy liquid is refined with nitrogen and a refining agent at a refining temperature of 720-760°C for 15-20 minutes. After refining, the aluminum alloy liquid is allowed to stand for 20-30 minutes. Through this process, the aluminum alloy melt is degassed, deslaged, and purified.

[0036] Further preferably, step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid; heating the aluminum ingot to melt at 720-730°C, and gradually heating the temperature to 750-760°C at a heating rate of 7-8°C / min; refining the aluminum alloy liquid with nitrogen and a refining agent, the refining temperature is 730-750°C, the time is 15-20min, and after refining, it is allowed to stand for 20-30min, through this process, the aluminum alloy melt is degassed, deslagging and purified.

[0037] Furthermore, the preparation method of the high-performance, high-temperature resistant aluminum alloy comprises the following steps:

[0038] Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization;

[0039] The atomization temperature is 850°C to 900°C, the atomization pressure is 3.3MPa to 3.8MPa, the atomization speed is 10 to 14Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 10 and 50 μm, D 50 20~35μm.

[0040] Further preferably, step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into the tundish, and preparing the aluminum alloy powder by atomization; the atomization temperature is 870°C to 880°C, the atomization pressure is 3.5MPa to 3.7MPa, the atomization speed is 12 to 13Kg / min, and the atomization gas is high-purity argon; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 20 and 40 μm, D 50 25~30μm.

[0041] It should be noted that the process parameters of atomization powder making determine the particle size distribution state of aluminum alloy powder, and the particle size distribution state has a certain influence on the melting, product density and grain size in the subsequent molding process. Specifically, if the atomization temperature is too low, it will cause partial solid phase or overcooling of the aluminum alloy, affecting its atomization effect and uniformity. If the atomization temperature is too high, it will cause overheating and burning of the aluminum alloy, affecting its structure and performance. Therefore, the atomization temperature is 870℃~880℃; if the atomization pressure is too low, the droplets of the aluminum alloy will be too large or irregular, affecting its flight and cooling process. If the atomization pressure is too high, the droplets of the aluminum alloy will be too small or too dispersed, affecting its deposition and molding effect. Therefore, the atomization pressure is 3.5MPa~3.7MPa; if the atomization speed is low, hollow powder will be produced. If the atomization speed is too high, it will affect the morphology of the particle size. The sphericity of the obtained aluminum alloy powder is greater than or equal to 95%, and the hollow powder rate is less than 0.1%. It helps to improve the density and mechanical properties of aluminum alloy parts, reduce the probability of defects such as pores and cracks inside additively manufactured metal parts, and improve the performance and life of the parts.

[0042] Furthermore, the preparation method of the high-performance, high-temperature resistant aluminum alloy comprises the following steps:

[0043] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0044] The aluminum alloy material is powdered to form a powder layer, and the powder layer is scanned by aurora under the protection of inert gas, with a laser power of 400-500W, a scanning speed of 800-1000mm / s, a layer spacing of 80-100μm, and a layer thickness of 40-50μm for additive manufacturing;

[0045] Further preferably, step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding; spreading the aluminum alloy material to form a powder layer, and performing aurora scanning on the powder layer under the protection of an inert gas, with a laser power of 450 to 500 W, a scanning speed of 800 to 850 mm / s, an interlayer spacing of 90 to 100 μm, and a layer thickness of 40 to 50 μm, to perform additive manufacturing;

[0046] It should be noted that the laser energy density has a significant impact on the forming quality. When the laser energy density is lower than 100 J / mm 3 When the laser energy density is higher than 170 J / mm, the surface of the aluminum alloy is rough. This may be due to the relatively low energy density, and part of the aluminum alloy powder material has not been completely melted, resulting in an increase in the surface roughness of the aluminum alloy. On the contrary, when the laser energy density is higher than 170 J / mm 3When the aluminum alloy powder is overheated, the temperature rises and falls too quickly, and the heat in the aluminum alloy product cannot be released in time, resulting in thermal stress, which causes the surface of the aluminum alloy to be distorted and deformed, and some even crack. Therefore, it is necessary to control the relevant parameters so that the laser energy density is controlled at 110-170 J / mm3, and it is further preferred to control the laser energy density at 120-150 J / mm 3 .

[0047] Furthermore, the preparation method of the high-performance, high-temperature resistant aluminum alloy comprises the following steps:

[0048] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0049] First, solution treatment is carried out at 500-520℃ for 2-3h, then water quenching is carried out at room temperature, and the quenching transfer time does not exceed 10s. Then, double-stage aging is carried out at 130-150℃ for 18-24h low-temperature aging treatment, and then high-temperature aging is carried out at 180-250℃ for 1-8h. After aging treatment, it is naturally cooled in air.

[0050] Further preferably, step (5) heat treatment: heat treatment of the aluminum alloy product after the forming process;

[0051] First, solution treatment is carried out at 500-520℃ for 2-3h, then water quenching is carried out at room temperature, and the quenching transfer time does not exceed 10s. Then, double-stage aging is carried out at 130-150℃ for 20-22h low-temperature aging treatment, and then high-temperature aging is carried out at 220-240℃ for 3-5h. After aging treatment, it is naturally cooled in the air.

[0052] Furthermore, the preparation method of the high-performance, high-temperature resistant aluminum alloy comprises the following steps:

[0053] Step (6) surface treatment: performing surface treatment on the aluminum alloy product after heat treatment; including surface cleaning, surface grinding, and surface sandblasting.

[0054] According to an embodiment of the present invention, the heat-resistant and high-strength aluminum alloy material includes 6.1%, 6.3%, 6.5%, 6.7%, 6.9%, and 7% Mg.

[0055] According to an embodiment of the present invention, the heat-resistant and high-strength aluminum alloy material includes 2.1%, 2.15%, 2.2%, 2.3%, 2.4%, and 2.5% of Mn.

[0056] According to an embodiment of the present invention, the heat-resistant and high-strength aluminum alloy material includes 1.7%, 1.75%, 1.8, 1.85%, and 1.9% Cu.

[0057] According to an embodiment of the present invention, the heat-resistant high-strength aluminum alloy material includes 0.4%, 0.45%, and 0.5% Sr.

[0058] According to an embodiment of the present invention, the heat-resistant and high-strength aluminum alloy material includes 0.05%, 0.07%, 0.08%, 0.085%, 0.09%, and 0.1% Be.

[0059] According to an embodiment of the present invention, the heat-resistant and high-strength aluminum alloy material includes 0.01%, 0.015%, 0.02%, 0.025%, and 0.03% of rare earth Ce.

[0060] The role of alloy elements in the present invention and the basis for setting:

[0061] (1)Mg

[0062] For Al-Mg alloy, the solid solubility of Mg in aluminum alloy is relatively large, and the strength of aluminum alloy can be improved by solid solution strengthening without causing the reduction of alloy plasticity. Al-Mg alloy has excellent solid solution strengthening, heat resistance and corrosion resistance. Mg element is the main element besides Al, forming β phase, which plays a strengthening role; in addition, by adding Cu to Al-Mg alloy, Mg and Cu coexist, a certain amount of Al2Cu and Al2CuMg can be precipitated, and precipitation strengthening is used to improve strength. Therefore, the Mg content is controlled at 6.1-7.0%, preferably, the Mg content is controlled at 6.3-6.7%.

[0063] (2) Mn

[0064] Mn has a large solid solubility in aluminum alloys. The present invention also introduces more Mn elements into the alloy system. Through solid solution strengthening, not only can the strength of aluminum alloys be improved, but Al and Mn can also form Al6Mn compound dispersed particles and distribute them on the grain boundaries, which have a pinning effect, hinder recrystallization, increase the recrystallization temperature of aluminum alloys, and inhibit the grain growth of aluminum alloys, which is beneficial to the simultaneous improvement of room temperature performance and high temperature performance of alloys; research has found that if combined with the rapid cooling process in the additive manufacturing process, a certain amount of Mn elements can also be dissolved into the alloy matrix, which is beneficial to the improvement of the mechanical properties of the alloy. It should be noted that the Mn content should not be too high, otherwise it is easy to form coarse Al6Mn compounds, causing segregation, deteriorating the mechanical properties of aluminum alloys, and reducing the alloy forming performance. Therefore, the Mn content is controlled at 2.1-2.5%, preferably, the Mn content is controlled at 2.2-2.4%.

[0065] (3)Cu

[0066] Cu has a large solid solubility in aluminum alloys. Cu and Mg are solid-dissolved in the Al parent phase, which has the effect of improving mechanical strength through solid solution strengthening. Adding Cu to Al-Mg alloys allows Mg and Cu to coexist, and a certain amount of Al2Cu and Al2CuMg can be precipitated, which improves strength by precipitation strengthening. It can also increase the binding force between aluminum atoms, slow down the diffusion process of atoms and the decomposition rate of the solid solution, and improve the thermal stability of aluminum alloys at high temperatures. When the Cu content is too high, it is also easy to cause thermal crack sensitivity of aluminum alloys, and it will also have an adverse effect on the corrosion resistance of aluminum alloys. Therefore, the Cu content is controlled at 1.7-1.9%, and preferably, the Cu content is controlled at 1.75-1.85%.

[0067] (4) Sr

[0068] In aluminum alloys, Sr microalloying can greatly improve the plasticity and toughness of the alloy without reducing the casting properties of the alloy. The Sr element helps to purify the alloy melt, remove impurities, and help dissolve the coarse second phase of the alloy during solid solution, hindering recrystallization and grain growth; the enhanced solid solution treatment significantly reduces the coarse second phase in the alloy and reduces the corrosion sensitivity. Since the Mg content in this system is relatively high, adding a certain amount of Sr element can reduce the segregation of Mg element and improve the uniformity of the internal composition of the alloy. Moreover, the Sr element has a significant improvement effect on the heat resistance of aluminum alloys, mainly due to the formation of Al4Sr phase and Al-Mg-Sr phase, which causes the high temperature heat resistance of the alloy to improve. Therefore, the Sr content is controlled at 0.4-0.5%, preferably, the Sr content is controlled at 0.45-0.5%.

[0069] (5)Be

[0070] The introduction of a trace amount of Be element in this system can expand the number of precipitated phases, reduce the size of precipitated phases, and accelerate aging hardening, which may be related to the close-packed hexagonal structure of beryllium and its low solubility in aluminum; and based on the high-temperature use environment above 250°C, atomization powder making, and additive manufacturing process design, Be can reduce the high-temperature oxidation phenomenon of the alloy and can effectively reduce the formation of oxide film on the surface of the alloy powder. Further combined with the high-purity argon environment in the additive manufacturing process, it can effectively inhibit the deep oxidation of the surface of the alloy powder and reduce the generation of oxidized inclusions, holes and bubbles in the additive manufacturing process. Therefore, the Be content is controlled at 0.05-0.10%, and preferably, the Be content is controlled at 0.07-0.09%.

[0071] (6) Rare earth Ce

[0072] The addition of rare earth element Ce plays the role of refining grains, inhibiting recrystallization, and increasing strength. Combined with heat treatment, the alloy matrix is ​​purified, the grain structure is refined, the secondary dendrites are reduced, and the grain boundary structure is improved, thereby achieving a simultaneous improvement in alloy strength and heat resistance. However, when the rare earth is excessive, the grain boundary density increases excessively, and the excess rare earth elements increase the matrix solid solubility, reduce the thermal conductivity of the alloy, and are not conducive to the high temperature resistance of the aluminum alloy. Therefore, the rare earth Ce content is controlled at 0.01-0.03%, and preferably, the Be content is controlled at 0.015-0.025%.

[0073] Beneficial effects of the present invention:

[0074] The present invention provides a high-performance, high-temperature resistant aluminum alloy and a preparation method thereof. The aluminum alloy is made of Al-Mg-Mn-Cu alloy as a matrix, appropriately adding microalloying elements, and is made through batching, smelting, atomization powder making, molding, heat treatment, and surface treatment. The aluminum alloy is suitable for the field of additive manufacturing. At room temperature: the yield strength of the aluminum alloy is 520-560MPa, the tensile strength is 580-640MPa, and the elongation is greater than 10%; at a high temperature of 250°C: the yield strength of the aluminum alloy is 260-300MPa, the tensile strength is 330-380MPa, and the elongation is greater than 16%; at a high temperature of 300°C: the yield strength of the aluminum alloy is 220-250MPa, the tensile strength is 300-330MPa, and the elongation is greater than 18%. It can meet the use requirements of high-temperature resistant aluminum alloys in multiple fields such as aerospace, transportation, oil exploration, high-voltage power transmission, and nuclear fuel storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1 is the size of the aluminum alloy powder after atomization powdering in Example 3;

[0076] Figure 2 is the surface roughness after the molding process is changed in Comparative Example 7;

[0077] Figure 3 The surface cracks after the molding process was changed in Comparative Example 8; DETAILED DESCRIPTION

[0078] The present invention will be described in further detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only exemplary descriptions and explanations of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect.

[0079] The methods / devices used in the following examples are conventional methods / devices unless otherwise specified; the raw materials used in the following examples are commercially available unless otherwise specified.

[0080] Example 1

[0081] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage, Mg: 6.1%, Mn: 2.5%, Cu: 1.9%, Sr: 0.4%, Be: 0.05%, rare earth Ce: 0.01%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum; the method comprises the following steps:

[0082] Step (1) batching: weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product;

[0083] The raw materials include aluminum ingots with aluminum content ≥99.7%, magnesium ingots with magnesium content ≥99.7%, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy.

[0084] Step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid;

[0085] The aluminum ingot is heated to melt at 720°C, and the temperature is gradually raised to 730°C at a heating rate of 5°C / min. During the heating process, magnesium ingots, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy, and AlCe10 master alloy are added, and the mixture is stirred and melted into aluminum alloy liquid. The aluminum alloy liquid is refined with nitrogen and a refining agent at a refining temperature of 720°C for 20 minutes. After refining, the mixture is allowed to stand for 20 minutes. Through this process, the aluminum alloy melt is degassed, deslaged, and purified.

[0086] Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization;

[0087] The atomization temperature is 870°C, the atomization pressure is 3.3MPa, the atomization speed is 10Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 10 and 50μm, D 50 20~35μm.

[0088] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0089] The aluminum alloy material is spread to form a powder layer. Under the protection of inert gas, the powder layer is scanned by aurora. The laser power is 400W, the scanning speed is 1000mm / s, the layer spacing is 90μm, and the layer thickness is 40μm for additive manufacturing; (the molding accuracy reaches ±0.05mm, the surface roughness Ra is less than 10μm, the density is greater than 99%, and there are no obvious microcracks in the sample microstructure)

[0090] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0091] First, solution treatment is carried out at 500°C for 2 hours, followed by water quenching at room temperature, with the quenching transfer time not exceeding 10 seconds. Double-stage aging is then carried out at 130°C for 18 hours of low-temperature aging treatment, followed by high-temperature aging at 180°C for 1 hour, and then naturally cooling in the air after aging treatment.

[0092] Step (6) surface treatment: performing surface treatment on the aluminum alloy product after heat treatment; including surface cleaning, surface grinding, and surface sandblasting.

[0093] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage, Mg: 6.3%, Mn: 2.4%, Cu: 1.8%, Sr: 0.45%, Be: 0.07%, rare earth Ce: 0.015%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum; the method comprises the following steps:

[0094] Step (1) batching: weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product;

[0095] The raw materials include aluminum ingots with aluminum content ≥99.7%, magnesium ingots with magnesium content ≥99.7%, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy.

[0096] Step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid;

[0097] The aluminum ingot is heated to melt at 730°C, and the temperature is gradually raised to 750°C at a heating rate of 7°C / min. During the heating process, magnesium ingots, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy, and AlCe10 master alloy are added, and the mixture is stirred and melted into aluminum alloy liquid. The aluminum alloy liquid is refined with nitrogen and a refining agent at a refining temperature of 730°C for 15 minutes. After refining, the mixture is allowed to stand for 30 minutes. Through this process, the aluminum alloy melt is degassed, deslaged, and purified.

[0098] Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization;

[0099] The atomization temperature is 850°C, the atomization pressure is 3.5MPa, the atomization speed is 12Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 10 and 50μm, D 50 20~35μm.

[0100] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0101] The aluminum alloy material is spread to form a powder layer. Under the protection of inert gas, the powder layer is laser scanned with a laser power of 500W, a scanning speed of 1000mm / s, a layer spacing of 100μm, and a layer thickness of 40μm for additive manufacturing; (the molding accuracy reaches ±0.05mm, the surface roughness Ra is less than 10μm, the density is greater than 99%, and there are no obvious microcracks in the sample microstructure)

[0102] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0103] First, solution treatment is carried out at 510℃ for 2.5h, then water quenching is carried out at room temperature, and the quenching transfer time does not exceed 10s. Then, double-stage aging is carried out at 140℃ for 20h low-temperature aging treatment, and then high-temperature aging is carried out at 220℃ for 3h. After aging treatment, it is naturally cooled in air.

[0104] Step (6) surface treatment: performing surface treatment on the aluminum alloy product after heat treatment; including surface cleaning, surface grinding, and surface sandblasting.

[0105] Example 3

[0106] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage, Mg: 6.5%, Mn: 2.3%, Cu: 1.8%, Sr: 0.45%, Be: 0.08%, rare earth Ce: 0.02%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum; the method comprises the following steps:

[0107] Step (1) batching: weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product;

[0108] The raw materials include aluminum ingots with aluminum content ≥99.7%, magnesium ingots with magnesium content ≥99.7%, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy.

[0109] Step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid;

[0110] The aluminum ingot is heated to melt at 730°C, and the temperature is gradually raised to 760°C at a heating rate of 8°C / min. During the heating process, magnesium ingot, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy are added, and the mixture is stirred and melted into aluminum alloy liquid. The aluminum alloy liquid is refined with nitrogen and a refining agent at a refining temperature of 750°C for 20 minutes. After refining, the mixture is allowed to stand for 30 minutes. Through this process, the aluminum alloy melt is degassed, deslaged and purified.

[0111] Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization;

[0112] The atomization temperature is 870°C, the atomization pressure is 3.7MPa, the atomization speed is 13Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 10 and 50μm, D 50 20~35μm.

[0113] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0114] The aluminum alloy material is powdered to form a powder layer. Under the protection of inert gas, the powder layer is laser scanned with a laser power of 400W, a scanning speed of 800mm / s, a layer spacing of 100μm, and a layer thickness of 40μm for additive manufacturing; (the molding accuracy reaches ±0.05mm, the surface roughness Ra is less than 8μm, the density is greater than 99.5%, and there are no obvious microcracks in the sample microstructure)

[0115] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0116] First, solution treatment is carried out at 500°C for 3 hours, followed by water quenching at room temperature, with the quenching transfer time not exceeding 10 seconds. Double-stage aging is then carried out at 130°C for 22 hours of low-temperature aging treatment, followed by high-temperature aging at 240°C for 5 hours, and then naturally cooling in the air after aging treatment.

[0117] Step (6) surface treatment: performing surface treatment on the aluminum alloy product after heat treatment; including surface cleaning, surface grinding, and surface sandblasting.

[0118] Example 4

[0119] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage, Mg: 6.7%, Mn: 2.2%, Cu: 1.7%, Sr: 0.5%, Be: 0.085%, rare earth Ce: 0.02%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum; the method comprises the following steps:

[0120] Step (1) batching: weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product;

[0121] The raw materials include aluminum ingots with aluminum content ≥99.7%, magnesium ingots with magnesium content ≥99.7%, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy.

[0122] Step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid;

[0123] The aluminum ingot is heated to melt at 725°C, and the temperature is gradually raised to 750°C at a heating rate of 7°C / min. During the heating process, magnesium ingots, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy, and AlCe10 master alloy are added, and the mixture is stirred and melted into aluminum alloy liquid. The aluminum alloy liquid is refined with nitrogen and a refining agent at a refining temperature of 730°C for 20 minutes. After refining, the mixture is allowed to stand for 20 minutes. Through this process, the aluminum alloy melt is degassed, deslaged, and purified.

[0124] Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization;

[0125] The atomization temperature is 880°C, the atomization pressure is 3.5MPa, the atomization speed is 12Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 10 and 50μm, D 50 20~35μm.

[0126] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0127] The aluminum alloy material is powdered to form a powder layer. Under the protection of inert gas, the powder layer is laser scanned with a laser power of 450W, a scanning speed of 850mm / s, a layer spacing of 90μm, and a layer thickness of 45μm for additive manufacturing; (the molding accuracy reaches ±0.05mm, the surface roughness Ra is less than 8μm, the density is greater than 99.5%, and there are no obvious microcracks in the sample microstructure)

[0128] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0129] First, solution treatment is carried out at 510℃ for 2.5h, then water quenching is carried out at room temperature, and the quenching transfer time does not exceed 10s. Then, double-stage aging is carried out at 140℃ for 20h low-temperature aging treatment, and then high-temperature aging is carried out at 220℃ for 3h. After aging treatment, it is naturally cooled in air.

[0130] Step (6) surface treatment: performing surface treatment on the aluminum alloy product after heat treatment; including surface cleaning, surface grinding, and surface sandblasting.

[0131] Example 5

[0132] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage, Mg: 6.9%, Mn: 2.15%, Cu: 1.75%, Sr: 0.45%, Be: 0.09%, rare earth Ce: 0.025%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum; the method comprises the following steps:

[0133] Step (1) batching: weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product;

[0134] The raw materials include aluminum ingots with aluminum content ≥99.7%, magnesium ingots with magnesium content ≥99.7%, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy.

[0135] Step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid;

[0136] The aluminum ingot is heated to melt at 730°C, and the temperature is gradually raised to 780°C at a heating rate of 10°C / min. During the heating process, magnesium ingots, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy, and AlCe10 master alloy are added, and the mixture is stirred and melted into aluminum alloy liquid. The aluminum alloy liquid is refined with nitrogen and a refining agent at a refining temperature of 760°C for 15 minutes. After refining, the mixture is allowed to stand for 20 minutes. Through this process, the aluminum alloy melt is degassed, deslaged, and purified.

[0137] Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization;

[0138] The atomization temperature is 870°C, the atomization pressure is 3.8MPa, the atomization speed is 14Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 10 and 50μm, D 50 20~35μm.

[0139] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0140] The aluminum alloy material is powdered to form a powder layer. Under the protection of inert gas, the powder layer is laser scanned with a laser power of 400W, a scanning speed of 800mm / s, a layer spacing of 80μm, and a layer thickness of 50μm for additive manufacturing; (the molding accuracy reaches ±0.05mm, the surface roughness Ra is less than 10μm, the density is greater than 99%, and there are no obvious microcracks in the sample microstructure)

[0141] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0142] First, solution treatment is carried out at 520℃ for 3h, then water quenching is carried out at room temperature, and the quenching transfer time does not exceed 10s. Then, double-stage aging is carried out at 150℃ for 24h low-temperature aging treatment, and then high-temperature aging is carried out at 240℃ for 7h. After aging treatment, it is naturally cooled in air.

[0143] Step (6) surface treatment: performing surface treatment on the aluminum alloy product after heat treatment; including surface cleaning, surface grinding, and surface sandblasting.

[0144] Example 6

[0145] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage, Mg: 7%, Mn: 2.1%, Cu: 1.85%, Sr: 0.4%, Be: 0.1%, rare earth Ce: 0.03%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum; the method comprises the following steps:

[0146] Step (1) batching: weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product;

[0147] The raw materials include aluminum ingots with aluminum content ≥99.7%, magnesium ingots with magnesium content ≥99.7%, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy.

[0148] Step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid;

[0149] The aluminum ingot is heated to melt at 725°C, and the temperature is gradually raised to 760°C at a heating rate of 8°C / min. During the heating process, magnesium ingots, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy, and AlCe10 master alloy are added, and the mixture is stirred and melted into aluminum alloy liquid. The aluminum alloy liquid is refined with nitrogen and a refining agent at a refining temperature of 750°C for 20 minutes. After refining, the mixture is allowed to stand for 20 minutes. Through this process, the aluminum alloy melt is degassed, deslaged, and purified.

[0150] Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization;

[0151] The atomization temperature is 900°C, the atomization pressure is 3.7MPa, the atomization speed is 13Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 10 and 50μm, D 50 20~35μm.

[0152] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0153] The aluminum alloy material is spread to form a powder layer. Under the protection of inert gas, the powder layer is laser scanned with a laser power of 500W, a scanning speed of 1000mm / s, a layer spacing of 80μm, and a layer thickness of 40μm for additive manufacturing; (the molding accuracy reaches ±0.05mm, the surface roughness Ra is less than 10μm, the density is greater than 99%, and there are no obvious microcracks in the sample microstructure)

[0154] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0155] First, solution treatment is carried out at 510℃ for 2h, then water quenching is carried out at room temperature, and the quenching transfer time does not exceed 10s. Then, double-stage aging is carried out at 130℃ for 20h, and then high-temperature aging is carried out at 250℃ for 8h. After aging treatment, it is naturally cooled in air.

[0156] Step (6) surface treatment: performing surface treatment on the aluminum alloy product after heat treatment; including surface cleaning, surface grinding, and surface sandblasting.

[0157] Comparative Example 1

[0158] Compared with Example 1, only the Mg and Mn contents are reduced. The relevant performance parameters are shown in Table 1.

[0159] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage: Mg: 6%, Mn: 2%, Cu: 1.9%, Sr: 0.4%, Be: 0.05%, rare earth Ce: 0.01%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0160] Comparative Example 2

[0161] Compared with Example 1, only the contents of Mg and Mn are increased. The relevant performance parameters are shown in Table 1.

[0162] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage: Mg: 7.1%, Mn: 2.6%, Cu: 1.9%, Sr: 0.4%, Be: 0.05%, rare earth Ce: 0.01%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0163] This may be due to the excessively high Mg and Mn contents, which form coarse Al 6 Mn compounds cause segregation, and the precipitated phase begins to crack, which deteriorates the mechanical properties of the aluminum alloy and reduces the alloy's forming properties.

[0164] Comparative Example 3

[0165] Compared with Example 2, only the Cu and Sr contents are reduced. The relevant performance parameters are shown in Table 1.

[0166] A high-performance, high-temperature resistant aluminum alloy material, which comprises, by mass percentage: Mg: 6.3%, Mn: 2.4%, Cu: 1.6%, Sr: 0.2%, Be: 0.07%, rare earth Ce: 0.015%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum;

[0167] Comparative Example 4

[0168] Compared with Example 3, Be is not contained. The relevant performance parameters are shown in Table 1.

[0169] Comparative Example 5

[0170] Compared with Example 3, no rare earth Ce is contained. The relevant performance parameters are shown in Table 1.

[0171] Comparative Example 6

[0172] Compared with Example 3, only the atomization process of step (3) is changed. The relevant performance parameters are shown in Table 1.

[0173] Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization;

[0174] The atomization temperature is 840°C, the atomization pressure is 3.2MPa, the atomization speed is 9.5Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 40 and 70μm, D 50 The sphericity of the Al alloy powder is less than 90%, and the hollow powder ratio is higher than 0.2%.

[0175] Comparative Example 7

[0176] Compared with Example 4, the molding process of step (4) is changed, and the relevant performance parameters are shown in Table 1.

[0177] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0178] The aluminum alloy material is spread to form a powder layer. Under the protection of inert gas, the powder layer is laser scanned with a laser power of 350W, a scanning speed of 600mm / s, a layer spacing of 120μm, and a layer thickness of 50μm for additive manufacturing. At this time, the laser energy density is 97.2J / mm 3 The aluminum alloy surface is rough. The forming accuracy reaches ±0.2mm, the surface roughness Ra is greater than 15μm, and the density is greater than 95%;

[0179] Comparative Example 8

[0180] Compared with Example 4, the molding process of step (4) is changed, and the relevant performance parameters are shown in Table 1.

[0181] Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding;

[0182] The aluminum alloy material is powdered to form a powder layer, and the powder layer is laser scanned under the protection of inert gas, with a laser power of 500W, a scanning speed of 1100mm / s, a layer spacing of 50μm, and a layer thickness of 50μm for additive manufacturing;

[0183] At this time, the laser energy density is 181.8J / mm 3 When , the sample microstructure has microcracks with a width greater than 2 μm;

[0184] Comparative Example 9

[0185] Compared with Example 4, the heat treatment process in step (5) is changed, and the relevant performance parameters are shown in Table 1.

[0186] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0187] First, solution treatment is carried out at 460°C for 15 hours, followed by water quenching at room temperature, with the quenching transfer time not exceeding 10 seconds. Double-stage aging is then carried out at 130°C for 5 hours of low-temperature aging treatment, followed by high-temperature aging at 180°C for 5 hours, and then naturally cooling in the air after aging treatment.

[0188] Comparative Example 10

[0189] Compared with Example 4, the heat treatment process in step (5) is changed, and the relevant performance parameters are shown in Table 1.

[0190] Step (5) heat treatment: heat treating the aluminum alloy product after the forming process;

[0191] First, solution treatment is carried out at 520℃ for 3h, then water quenching is carried out at room temperature, and the quenching transfer time does not exceed 10s. Then single-stage aging is carried out at 250℃ for 8h high-temperature aging, and natural cooling is carried out in air after aging treatment.

[0192] The room temperature and high temperature mechanical properties of the additively manufactured aluminum alloy products of the embodiments and comparative examples were tested. GB / T228.1 “Metallic Materials Tensile Test Part 1: Room Temperature Test Method” and GB / T 4338 “Metallic Materials High Temperature Tensile Test Method” were used to test the mechanical properties of the additively manufactured aluminum alloy products. The test results are shown in Table 1.

[0193] Table 1 Performance test results of heat-resistant high-strength aluminum alloy materials of the embodiments and comparative examples

[0194]

[0195]

[0196]

[0197] The present invention has been described above with the aid of examples and comparative examples. However, the present invention is not limited to the above-mentioned embodiments. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-performance, high-temperature resistant aluminum alloy, wherein: The high-performance, high-temperature resistant aluminum alloy material is calculated by mass percentage as follows: Mg: 6.1-7%, Mn: 2.1-2.5%, Cu: 1.7-1.9%, Sr: 0.4-0.5%, Be: 0.05-0.10%, rare earth Ce: 0.01-0.03%, Fe≤0.05wt%, C≤0.01wt%, H≤0.015wt%, O≤0.05wt%, N≤0.02wt%, impurity elements≤0.2%, and the balance is aluminum.

2. The high-performance, high-temperature resistant aluminum alloy according to claim 1, wherein: After batching, smelting, atomization powder making, molding, heat treatment and surface treatment, At room temperature: the yield strength of aluminum alloy is 520-560MPa, the tensile strength is 580-640MPa, and the elongation is greater than 10%; At 250℃, the yield strength of aluminum alloy is 260-300MPa, the tensile strength is 330-380MPa, and the elongation is greater than 16%; At a high temperature of 300°C: the yield strength of the aluminum alloy is 220-250 MPa, the tensile strength is 300-330 MPa, and the elongation is greater than 18%.

3. The high-performance, high-temperature resistant aluminum alloy according to claim 1 or 2, wherein: The high-performance, high-temperature resistant aluminum alloy material is composed of Mg: 6.3-6.7%, Mn: 2.2-2.4%, Cu: 1.75-1.85%, Sr: 0.45-0.5%, Be: 0.07-0.09%, rare earth Ce: 0.015-0.025%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum; Alternatively, the high-performance, high-temperature resistant aluminum alloy material is calculated by mass percentage as follows: Mg: 6.1%, Mn: 2.5%, Cu: 1.9%, Sr: 0.4%, Be: 0.05%, rare earth Ce: 0.01%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, the balance is aluminum; Alternatively, the high-performance, high-temperature resistant aluminum alloy material is calculated by mass percentage as follows: Mg: 6.3%, Mn: 2.4%, Cu: 1.8%, Sr: 0.45%, Be: 0.07%, rare earth Ce: 0.015%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, the balance is aluminum; Alternatively, the high-performance, high-temperature resistant aluminum alloy material is calculated by mass percentage as follows: Mg: 6.5%, Mn: 2.3%, Cu: 1.8%, Sr: 0.45%, Be: 0.08%, rare earth Ce: 0.02%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, the balance is aluminum; Alternatively, the high-performance, high-temperature resistant aluminum alloy material is calculated by mass percentage as follows: Mg: 6.7%, Mn: 2.2%, Cu: 1.7%, Sr: 0.5%, Be: 0.085%, rare earth Ce: 0.02%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, the balance is aluminum; Alternatively, the high-performance, high-temperature resistant aluminum alloy material is calculated by mass percentage as follows: Mg: 6.9%, Mn: 2.15%, Cu: 1.75%, Sr: 0.45%, Be: 0.09%, rare earth Ce: 0.025%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, the balance is aluminum; Alternatively, the high-performance, high-temperature resistant aluminum alloy material is calculated by mass percentage as follows: Mg: 7%, Mn: 2.1%, Cu: 1.85%, Sr: 0.4%, Be: 0.1%, rare earth Ce: 0.03%, Fe≤0.03wt%, C≤0.01wt%, H≤0.01wt%, O≤0.03wt%, N≤0.01wt%, impurity elements≤0.2%, and the balance is aluminum.

4. A method for preparing the high-performance, high-temperature resistant aluminum alloy according to any one of claims 1 to 3, comprising the following steps: (1) Batching: Weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product; (2) Melting: preheating and drying the prepared alloy raw materials, and then melting them to obtain aluminum alloy liquid; (3) Atomization powder making: Control the melting temperature, input the aluminum alloy liquid into the tundish, and prepare aluminum alloy powder by atomization; (4) Molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding; (5) Heat treatment: heat treatment of the aluminum alloy products after forming; (6) Surface treatment: Surface treatment is performed on the aluminum alloy products after heat treatment.

5. The method for preparing the high-performance, high-temperature resistant aluminum alloy according to claim 4, comprising the following steps: Step (1) batching: weighing high-purity alloy raw materials based on the weight percentage of the target aluminum alloy product; The raw materials include aluminum ingots with aluminum content ≥99.7%, magnesium ingots with magnesium content ≥99.7%, AlMn10 master alloy, AlCu50A master alloy, AlSr10 master alloy, AlBe3 master alloy and AlCe10 master alloy.

6. The method for preparing the high-performance, high-temperature resistant aluminum alloy according to claim 5, comprising the following steps: Step (2) smelting: preheating and drying the prepared alloy raw materials, and then smelting to obtain aluminum alloy liquid; The aluminum ingot is heated and melted at 720-730°C, and the temperature is gradually raised to 730-780°C at a heating rate of 5-10°C / min. During the heating process, magnesium ingots, AlMn10 master alloys, AlCu50A master alloys, AlSr10 master alloys, AlBe3 master alloys, and AlCe10 master alloys are added, and the mixture is stirred and melted into aluminum alloy liquid. The aluminum alloy liquid is refined with nitrogen and a refining agent at a refining temperature of 720-760°C for 15-20 minutes. After refining, the aluminum alloy liquid is allowed to stand for 20-30 minutes. Through this process, the aluminum alloy melt is degassed, deslaged, and purified.

7. The method for preparing the high-performance, high-temperature resistant aluminum alloy according to claim 6, comprising the following steps: Step (3) atomization powder making: controlling the temperature of the aluminum alloy liquid, inputting the aluminum alloy liquid into a tundish, and preparing aluminum alloy powder by atomization; The atomization temperature is 850°C to 900°C, the atomization pressure is 3.3MPa to 3.8MPa, the atomization speed is 10 to 14Kg / min, and the atomization gas is high-purity argon gas; the particle size distribution of the aluminum alloy powder prepared by the atomization method is between 10 and 50 μm, D 50 20~35μm.

8. The method for preparing the high-performance, high-temperature resistant aluminum alloy according to claim 1, comprising the following steps: Step (4) molding: placing the aluminum alloy powder prepared by atomization into a vacuum drying oven for drying and molding; The aluminum alloy material is powdered to form a powder layer. Under the protection of inert gas, the powder layer is scanned with an aurora. The laser power is 400-500W, the scanning speed is 800-1000mm / s, the layer spacing is 80-100μm, and the layer thickness is 40-50μm for additive manufacturing.

9. The method for preparing the high-performance, high-temperature resistant aluminum alloy according to claim 1, comprising the following steps: Step (5) heat treatment: heat treating the aluminum alloy product after the forming process; First, solution treatment is carried out at 500-520℃ for 2-3h, then water quenching is carried out at room temperature, and the quenching transfer time does not exceed 10s. Then, double-stage aging is carried out at 130-150℃ for 18-24h low-temperature aging treatment, and then high-temperature aging is carried out at 180-250℃ for 1-8h. After aging treatment, it is naturally cooled in air.

10. The method for preparing the high-performance, high-temperature resistant aluminum alloy according to claim 1, comprising the following steps: Step (6) surface treatment: performing surface treatment on the aluminum alloy product after heat treatment; Including surface cleaning, surface grinding and surface sand blasting.

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