5xxx series aluminum alloy wire rod and method of making same, aluminum alloy article and method of making same

Abstract

The application provides a 5xxx series aluminum alloy wire and a preparation method thereof, and an aluminum alloy part and a preparation method thereof. The 5xxx series aluminum alloy wire contains the following elements in percentage by mass: 4.0-6.0% of Mg, 2.0-4.0% of Zn, 0.1-0.8% of Mn, 0.05-0.40% of Sc, 0.05-0.25% of Zr, ≤0.10% of Fe, ≤0.08% of Si, ≤0.15% of unavoidable impurities, and the balance of Al; the total mass content of Sc and Zr is 0.25-0.50%; and the volume fraction of Al3(Sc, Zr) nanoparticles in the 5xxx series aluminum alloy wire is 0.2-0.55%. The above aluminum alloy wire has high strength, is not prone to cracking and has good formability after electric arc additive manufacturing and heat treatment.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy technology, and more specifically, to a 5xxx series aluminum alloy wire and its preparation method, and aluminum alloy parts and their preparation methods. Background Technology

[0002] Additive manufacturing is a technology that uses materials such as filaments and powders to deposit solid objects layer by layer. It can efficiently produce small batches of products with complex structures and has broad application prospects in aerospace, weaponry, and other fields. Electric arc additive manufacturing (WAAM) technology uses an electric arc as a heat source and metal filaments as raw materials. By depositing the filaments layer by layer along a planned path, near-net-shape components are obtained. Furthermore, WAAM technology features high manufacturing efficiency, low production costs, and suitability for forming large-size parts.

[0003] Aluminum alloys are widely used in the aerospace field due to their low density and good overall performance. Currently, the aluminum alloy wires used in arc additive manufacturing are mainly Al-Si, Al-Mg, and some Al-Cu alloys. The strength of these wires after arc additive manufacturing is generally below 300 MPa, and after heat treatment, the strength is around 400 MPa, which cannot meet the future equipment development needs of the aerospace field. Therefore, there is a need to develop a high-strength aluminum alloy wire suitable for arc additive manufacturing. Summary of the Invention

[0004] The main objective of this invention is to provide a 5xxx series aluminum alloy wire and its preparation method, as well as an aluminum alloy part and its preparation method, to solve the problems of low strength and easy cracking of aluminum alloy wires used in additive manufacturing in the prior art.

[0005] To achieve the above objectives, according to one aspect of the present invention, a 5xxx series aluminum alloy wire is provided, comprising, by mass percentage, the following elements: 4.0~6.0% Mg; 2.0~4.0% Zn; 0.1~0.8% Mn; 0.05~0.40% Sc; 0.05~0.25% Zr; Fe ≤0.10%; Si ≤0.08%; total unavoidable impurities ≤0.15%; and the balance being Al; the total mass content of Sc and Zr is 0.25~0.50%; and the volume fraction of Al3(Sc, Zr) nanoparticles in the 5xxx series aluminum alloy wire is 0.2~0.55%.

[0006] Furthermore, by mass percentage, 5xxx series aluminum alloy wire comprises the following elements: 4.5~6.0% Mg; 2.5~4.0% Zn; 0.1~0.5% Mn; 0.08~0.35% Sc; 0.07~0.20% Zr; 0.03~0.10% Fe; 0.02~0.08% Si, with unavoidable impurities totaling ≤0.15%, and the balance being Al.

[0007] Furthermore, the mass ratio of Sc to Zr is 1~4:1; and / or the mass ratio of Mg to Zn is 1.5~2.4:1; and / or the diameter of the 5xxx series aluminum alloy wire is 1.0~1.6mm.

[0008] According to another aspect of the present invention, a method for preparing the above-mentioned 5xxx series aluminum alloy wire is provided. The preparation method includes: step S1, after batching the raw materials corresponding to the aluminum alloy, performing melting, refining, casting, homogenization heat treatment and hot rolling in sequence to obtain a bar; step S2, performing multiple annealing, drawing and wire scraping on the bar in sequence to obtain 5xxx series aluminum alloy wire.

[0009] Further, step S1 above also includes: step S11, after the pure aluminum ingot is first melted, Al-Sc master alloy, Al-Zr master alloy, Al-Mn master alloy and pure zinc ingot are added for a second melting to obtain a first alloy liquid; step S12, after the first alloy liquid is stirred, allowed to stand and first degassed and refined, pure magnesium ingot is added for a third melting to obtain a second alloy liquid; step S13, the second alloy liquid is second degassed and refined and cast to obtain an ingot; the ingot is then subjected to homogenization heat treatment, cooling and... Hot rolling yields bars; wherein the first melting temperature is 840~860℃ and the first melting time is 2~6h; the second melting temperature is 780~800℃ and the second melting time is 1~3h; the third melting temperature is 750~770℃ and the third melting time is 10~20min; the first degassing and refining temperature is 720~760℃ and the first degassing and refining time is 15~25min; the second degassing and refining temperature is 710~750℃ and the second degassing and refining time is 15~25min.

[0010] Further, in step S1 above, the homogenization heat treatment temperature is 470~473℃, and the homogenization heat treatment time is 24~30h; and / or, hot rolling includes hot roughing and hot finishing rolling performed sequentially, with a processing rate of 90~98% for hot roughing and 80~85% for hot finishing, and a hot rolling temperature of 440~450℃; and / or, step S2 above further includes: cold rolling the bar to obtain cold-rolled wire, and subjecting the cold-rolled wire to multiple passes of annealing, drawing, and wire scraping to obtain 5xxx series aluminum alloy wire; and / or, the temperature of the multiple passes of annealing is 430~450℃.

[0011] According to another aspect of the present invention, a method for preparing an aluminum alloy part is provided, the method comprising: performing arc additive manufacturing on the above-mentioned 5xxx series aluminum alloy wire to obtain an arc additive manufacturing component; and performing heat treatment on the arc additive manufacturing component to obtain an aluminum alloy part.

[0012] Furthermore, the voltage of the arc additive manufacturing is 12.0~15.0V, and the current is 100~150A; and / or, the volume fraction of Al3(Sc, Zr) nanoparticles in the arc additive manufactured component is 0.15~0.35%; the Mg content in the arc additive manufactured component is... 32 (Al, Zn) 49 The volume fraction of the phase is 1.8~3.3%; and / or, the density of the arc additive manufacturing component is ≥99%; the average grain size of the arc additive manufacturing component is 10~30μm; the yield strength of the arc additive manufacturing component is ≥220MPa, the tensile strength of the arc additive manufacturing component is ≥320MPa, and the elongation of the arc additive manufacturing component is ≥8%.

[0013] Furthermore, the heat treatment includes solution treatment and aging performed sequentially; wherein the solution treatment temperature is 470~473℃, and the solution treatment time is 4~8h; the aging temperature is 150~160℃, and the aging time is 5~15h; Mg in the aluminum alloy parts 32 (Al,Zn) 49 The volume fraction of the phase is 3.5~5.0%; and / or, the yield strength of the aluminum alloy part is ≥350MPa, the tensile strength of the aluminum alloy part is ≥450MPa, and the elongation of the aluminum alloy part is ≥10%.

[0014] According to another aspect of the present invention, an aluminum alloy part is provided, which is prepared by the above-described preparation method.

[0015] Applying the technical solution of this invention, the 5xxx series aluminum alloy wire of this application incorporates Sc and Zr elements, and controls the total mass of Sc and Zr elements within the aforementioned range. During the arc additive manufacturing process, Al3(Sc, Zr) multi-component composite nanoparticles are formed, acting as heterogeneous nucleation elements, thereby refining the grain size and inhibiting cracking. Simultaneously, adding a small amount of Mn element to the 5xxx series alloy wire enables the formation of Al6Mn nanoparticles during the arc additive manufacturing process, acting as heterogeneous nucleation elements, thereby further refining the grain size. Adding the aforementioned amount of Zn element enables the formation of the T phase (Mg). 32 (Al, Zn) 49 The formation of the T phase enhances the mechanical properties of 5xxx series aluminum alloy wires by controlling the mass content of Al3(Sc, Zr) nanoparticles within the aforementioned range. This allows the tensile strength of 5xxx series aluminum alloy wires after additive manufacturing to reach ≥320MPa, while simultaneously suppressing cracking. The formation of the T phase further enhances the tensile strength of the additively manufactured aluminum alloy after heat treatment to reach ≥450MPa, thus meeting the mechanical property requirements of aluminum alloys in aerospace and other fields. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0017] Figure 1 The surface morphology of the 5xxx series aluminum alloy wire in Embodiment 5 of this application is shown;

[0018] Figure 2 A metallographic diagram of the arc additive manufacturing component in Embodiment 5 of this application is shown;

[0019] Figure 3 A grain structure diagram of the arc additive manufacturing component in Embodiment 5 of this application is shown;

[0020] Figure 4 SEM images of the aluminum alloy part in Embodiment 5 of this application are shown;

[0021] Figure 5 The surface morphology of the 5xxx series aluminum alloy wire in Comparative Example 4 of this application is shown;

[0022] Figure 6 A metallographic diagram of the arc additive manufacturing component in Comparative Example 4 of this application is shown;

[0023] Figure 7 A grain structure diagram of the arc additive manufacturing component in Comparative Example 4 of this application is shown;

[0024] Figure 8SEM images of the aluminum alloy parts in Comparative Example 4 of this application are shown. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] As analyzed in the background section of this application, the existing aluminum alloy wires used in additive manufacturing have the problems of low strength and easy cracking. In order to solve the above problems, this application provides a 5xxx series aluminum alloy wire and its preparation method, as well as an aluminum alloy part and its preparation method.

[0027] In a typical embodiment of this application, a 5xxx series aluminum alloy wire is provided, comprising, by mass percentage, the following elements: 4.0~6.0% Mg, 2.0~4.0% Zn, 0.1~0.8% Mn, 0.05~0.40% Sc, 0.05~0.25% Zr, Fe ≤0.10%, Si ≤0.08%, unavoidable impurities ≤0.15%, and the balance being Al; the total mass content of Sc and Zr is 0.25~0.50%; and the volume fraction of Al3(Sc, Zr) nanoparticles in the 5xxx series aluminum alloy wire is 0.2~0.55%.

[0028] The 5xxx series aluminum alloy wire of this application incorporates Sc and Zr elements, with the total mass of Sc and Zr elements controlled within the aforementioned range. During the arc additive manufacturing process, Al3(Sc, Zr) multi-component composite nanoparticles are formed, acting as heterogeneous nucleation elements, thereby refining the grain size and inhibiting cracking. Simultaneously, the addition of a small amount of Mn element to the 5xxx series alloy wire enables the formation of Al6Mn nanoparticles during the arc additive manufacturing process, also acting as heterogeneous nucleation elements, further refining the grain size. The addition of the aforementioned amount of Zn element allows the formation of the T phase (Mg). 32 (Al, Zn) 49 The formation of the T phase enhances the mechanical properties of 5xxx series aluminum alloy wires by controlling the mass content of Al3(Sc, Zr) nanoparticles within the aforementioned range. This allows the tensile strength of 5xxx series aluminum alloy wires after additive manufacturing to reach ≥320MPa, while simultaneously suppressing cracking. The formation of the T phase further enhances the tensile strength of the additively manufactured aluminum alloy after heat treatment to reach ≥450MPa, thus meeting the mechanical property requirements of aluminum alloys in aerospace and other fields.

[0029] Furthermore, compared to 7xxx series aluminum alloy wires, 5xxx series aluminum alloy wires generally exhibit superior weldability, resulting in better additive manufacturing formability. Additionally, their arc-additively formed microstructure contains fewer coarse eutectic phases, leading to higher elongation in the arc-additively formed components.

[0030] To further improve the mechanical properties of 5xxx series aluminum alloy wire, in one embodiment of this application, the 5xxx series aluminum alloy wire comprises the following elements by mass percentage: 4.5~6.0% Mg, 2.5~4.0% Zn, 0.1~0.5% Mn, 0.08~0.35% Sc, 0.07~0.20% Zr, 0.03~0.10% Fe, 0.02~0.08% Si, with the total content of unavoidable impurities ≤0.15%, and the balance being Al.

[0031] In one embodiment of this application, the mass ratio of Sc to Zr is 1~4:1; and / or, the mass ratio of Mg to Zn is 1.5~2.4:1; and / or, the diameter of the 5xxx series aluminum alloy wire is 1.0~1.6mm.

[0032] Preferably controlling the mass ratio of Sc to Zr within the aforementioned range helps to form Al3(Sc, Zr) multi-component composite nanoparticles, thereby promoting the formation of fine grains and improving the strength and ductility of arc additive manufacturing components. Simultaneously, it also helps 5xxx series aluminum alloy wires to redefine dispersed Al3(Sc, Zr) multi-component composite nanoparticles after arc additive manufacturing, which act as solidification nucleation cores, playing a role in grain refinement and reducing cracking.

[0033] Preferably controlling the mass ratio of Zn to Mg within the above range helps to promote the T phase (Mg 32 (Al, Zn) 49 The formation of the T-phase strengthening phase enhances the strength of 5xxx series aluminum alloy wire. It also promotes the precipitation of the T-phase strengthening phase after heat treatment following arc additive manufacturing, further improving the mechanical properties of the aluminum alloy parts.

[0034] Preferably controlling the Mn element within the above range also helps the wire to generate an Al6(Fe,Mn) dispersed phase during the arc additive manufacturing process, which helps to refine the grains of the arc additive forming structure, thereby improving the performance of the components manufactured by arc additive manufacturing.

[0035] Preferably controlling the diameter of 5xxx series aluminum alloy wire within the above range helps to achieve uniform melting and deposition during the arc additive manufacturing process, forming a good interlayer bond, thereby improving the density and overall performance of aluminum alloy parts.

[0036] In another typical embodiment of this application, a method for preparing the above-mentioned 5xxx series aluminum alloy wire is provided. The preparation method includes: step S1, after the raw materials corresponding to the aluminum alloy are batched, they are successively smelted, refined, cast, homogenized heat treatment and hot rolled to obtain a bar; step S2, the bar is successively annealed, drawn and scraped in multiple passes to obtain 5xxx series aluminum alloy wire.

[0037] The 5xxx series aluminum alloy wire obtained by the above preparation method in this application has good mechanical properties and is not prone to cracking. Specifically, the raw materials are batched according to the elemental composition requirements of the 5xxx series aluminum alloy wire, and the raw materials are completely melted through smelting. Refining removes gases and inclusions from the alloy melt, thereby improving the purity of the aluminum alloy. After initial forming by casting, homogenization heat treatment is performed to eliminate component segregation, thereby improving the microstructure of the aluminum alloy. Hot rolling forms bars, preparing them for further processing. Multiple annealing passes on the bars eliminate work hardening, restore the ductility and plasticity of the material, ensure the smooth progress of the drawing process, and reduce potential cracks and fractures during drawing. The wire diameter is gradually reduced to the required 5xxx series aluminum alloy wire specifications through drawing. Scraping removes any oxide layer or other surface defects that may form on the wire surface after drawing, ensuring a smooth and clean surface for the 5xxx series aluminum alloy wire. In summary, the preparation method of this application can produce high-quality, high-purity 5xxx series aluminum alloy wires, which are suitable for additive manufacturing, and the resulting aluminum alloy parts have excellent microstructure and mechanical properties.

[0038] In one embodiment of this application, step S1 further includes: step S11, after the pure aluminum ingot is first melted, Al-Sc master alloy, Al-Zr master alloy, Al-Mn master alloy and pure zinc ingot are added for a second melting to obtain a first alloy liquid; step S12, after the first alloy liquid is stirred, allowed to stand and first degassed and refined, pure magnesium ingot is added for a third melting to obtain a second alloy liquid; step S13, the second alloy liquid is second degassed and refined and cast to obtain an ingot; the ingot is then subjected to homogenization heat treatment, The material is cooled and hot-rolled to obtain bars; wherein the first melting temperature is 840~860℃ and the first melting time is 2~6h; the second melting temperature is 780~800℃ and the second melting time is 1~3h; the third melting temperature is 750~770℃ and the third melting time is 10~20min; the first degassing and refining temperature is 720~760℃ and the first degassing and refining time is 15~25min; the second degassing and refining temperature is 710~750℃ and the second degassing and refining time is 15~25min.

[0039] The preferred temperatures and times for the first and second melting processes are within the ranges described above, which helps to fully melt the pure aluminum ingot, the pure zinc ingot, and the aforementioned intermediate alloy, thereby helping to ensure that the alloying elements are evenly distributed in the molten aluminum.

[0040] The first and second degassing refining processes are independent, each including the introduction of pure argon for degassing and refining. Preferably, the temperature and time of the first degassing refining are within the aforementioned range, which helps remove dissolved gases from the first alloy melt, reducing porosity and oxides in the material, thereby improving the density and mechanical properties of the aluminum alloy wire. Preferably, after the first degassing refining, pure magnesium ingots are added for a third melting process. Controlling the temperature and time of the third melting within the aforementioned range helps the magnesium element to fully dissolve and uniformly distribute in the first alloy melt, thereby improving the strength of the aluminum alloy wire. Preferably, the temperature and time of the second degassing refining are within the aforementioned range, which helps to further remove gases from the second alloy melt, thereby improving the quality of the aluminum alloy wire.

[0041] The preferred Al-Sc master alloy has a Sc content of 1.8-2.2%, and the preferred Al-Zr master alloy has a Zr content of 3.8-4.2%.

[0042] In one embodiment of this application, in step S1 above, the homogenization heat treatment temperature is 470~473℃, and the homogenization heat treatment time is 24~30h; and / or, hot rolling includes hot roughing and hot finishing rolling performed sequentially, the processing rate of hot roughing is 90~98%, the processing rate of hot finishing is 80~85%, and the hot rolling temperature is 440~450℃; and / or, step S2 further includes: cold rolling the bar to obtain cold-rolled wire, and subjecting the cold-rolled wire to multiple passes of annealing, drawing, and wire scraping to obtain 5xxx series aluminum alloy wire; and / or, the temperature of the multiple passes of annealing is 430~450℃.

[0043] Preferably controlling the temperature and time of the homogenization heat treatment within the aforementioned range not only helps promote grain size homogenization and the dissolution of most eutectic phases, thereby improving the machinability of the aluminum alloy, but also helps reduce internal stress generated during casting, thus reducing the likelihood of cracking during subsequent processing and improving the forming quality of the aluminum alloy wire. Preferably controlling the hot rolling temperature within the aforementioned range helps to further refine the grain size and mitigate the performance degradation caused by grain growth. Preferably controlling the hot finishing rolling rate within the aforementioned range further refines the grains, thereby improving the strength and plasticity of the aluminum alloy wire.

[0044] The preferred material is bar stock, which is then cold-rolled to obtain wire. The preferred multi-pass annealing temperature is within the aforementioned range, which helps reduce internal stress, restore the ductility and plasticity of the wire, and thus facilitates subsequent drawing and forming.

[0045] In another typical embodiment of this application, a method for preparing an aluminum alloy part is provided, the method comprising: performing arc additive manufacturing on the above-mentioned 5xxx series aluminum alloy wire to obtain an arc additive manufacturing component; and performing heat treatment on the arc additive manufacturing component to obtain the aluminum alloy part.

[0046] This application utilizes the aforementioned 5xxx series aluminum alloy wire for arc additive manufacturing, enabling the aluminum alloy wire to be deposited layer by layer along a planned path to obtain arc additive manufactured components with complex structures. Furthermore, the arc additive manufacturing process promotes the formation of Al3(Sc,Zr) multi-component composite nanoparticles, thereby refining grains and inhibiting solidification cracking, thus improving the strength of the arc additive manufactured components and reducing their susceptibility to cracking. Heat treatment of the arc additive manufactured components can promote the formation of the T-phase (Mg... 32 (Al, Zn) 49 The strengthening phase redissolves and precipitates, forming fine and dispersed strengthening particles, thereby greatly improving the strength of aluminum alloy parts and better meeting the requirements of aerospace and other fields for the mechanical properties of aluminum alloys.

[0047] In one embodiment of this application, the voltage of the arc additive manufacturing is 12.0~16.0V, the current of the arc additive manufacturing is 100~150A; and / or, the volume fraction of Al3(Sc, Zr) nanoparticles in the arc additive manufactured component is 0.15~0.35%; the Mg content in the arc additive manufactured component is... 32 (Al, Zn) 49 The volume fraction of the phase is 1.8~3.3%; and / or, the density of the arc additive manufacturing component is ≥99%; the average grain size of the arc additive manufacturing component is 10~30μm; the yield strength of the arc additive manufacturing component is ≥220MPa, the tensile strength of the arc additive manufacturing component is ≥320MPa, and the elongation of the arc additive manufacturing component is ≥8%.

[0048] Preferred control of the voltage and current in arc additive manufacturing within the above-mentioned range helps to promote the formation of Al3(Sc, Zr) nanoparticles and the T phase, ensuring their content reaches the above-mentioned range, thereby improving the strength and density of the arc additive manufactured components, ensuring their mechanical properties reach the above-mentioned range, and making them less prone to cracking.

[0049] In one embodiment of this application, the heat treatment includes sequential solution treatment and aging; wherein the solution treatment temperature is 470~473℃, and the solution treatment time is 4~8h; the aging temperature is 150~160℃, and the aging time is 5~15h; Mg in the aluminum alloy part 32 (Al, Zn) 49The volume fraction of the phase is 3.5~5.0%; and / or, the yield strength of the aluminum alloy part is ≥350MPa, the tensile strength of the aluminum alloy part is ≥450MPa, and the elongation of the aluminum alloy part is ≥10%.

[0050] Preferably controlling the solution temperature and time, and the aging temperature and time within the above ranges helps to promote the redissolution and precipitation of the T phase, ensuring its content reaches the above range, thereby improving the strength of aluminum alloy parts and ensuring their mechanical properties reach the above range, thus better meeting the requirements of aerospace and other fields for the mechanical properties of aluminum alloys.

[0051] In another typical embodiment of this application, an aluminum alloy part is provided, which is prepared by the above-described preparation method.

[0052] The aluminum alloy parts prepared by the above method have high strength and are not easy to crack, making them better suited for applications in aerospace and other fields.

[0053] The beneficial effects of this application will be further illustrated below with reference to the embodiments.

[0054] Example 1

[0055] Preparation of 5xxx series aluminum alloy wire:

[0056] The aluminum alloy raw materials are formulated by mass percentage as follows: 4.0% Mg, 2.0% Zn, 0.1% Mn, 0.15% Sc, 0.12% Zr, 0.08% Fe, 0.06% Si, with the balance being Al.

[0057] Pure aluminum ingots were heated to 850℃ for the first melting. When the furnace temperature reached 790℃, Al-2Sc master alloy, Al-4Zr master alloy, and pure zinc ingots were added for the second melting, resulting in the first alloy liquid. This was then followed by stirring and settling. When the settling temperature reached 740℃, the first degassing and refining process was performed, involving the introduction of pure argon for degassing and stirring for 20 minutes. At 760℃, pure magnesium ingots were added for the third melting, resulting in the second alloy liquid. This second alloy liquid underwent a second degassing and refining process, involving the introduction of pure argon for degassing and stirring for 20 minutes, and was subsequently cast into ingots (round ingots) with a diameter of 162mm.

[0058] The round ingots were heated to 470℃ for homogenization heat treatment for 30 hours, then air-cooled after removal from the furnace. The ingots were then machined into round ingots with a diameter of 145mm. The round ingots were then hot-rolled at 440℃. The hot rolling process consisted of first hot rough rolling to obtain bars with a diameter of 20mm, with a processing rate of 98%, and then hot finish rolling to obtain bars with a diameter of 8mm, with a processing rate of 84%.

[0059] The bar material is subjected to multiple annealing, drawing, wire scraping and cleaning processes to obtain 5xxx series aluminum alloy wire with a diameter of 1.2mm. The annealing temperature is 440℃.

[0060] Preparation of aluminum alloy parts:

[0061] 5xxx series aluminum alloy wire was manufactured using CMT (Continuous Arc Technology) to obtain an arc-manufactured component. The arc-manufacture voltage was 15.0V and the arc-manufacture current was 125A. The arc-manufactured component was then subjected to heat treatment. The heat treatment consisted of solution treatment at 470℃ for 4 hours and aging at 155℃ for 10 hours.

[0062] Example 2

[0063] The difference from Example 1 lies in the preparation of the 5xxx series aluminum alloy wire: The aluminum alloy raw materials were proportioned by mass percentage as follows: 4.5% Mg, 2.3% Zn, 0.2% Mn, 0.18% Sc, 0.14% Zr, 0.07% Fe, 0.04% Si, with the balance being Al. The homogenization heat treatment temperature was 472℃, ultimately yielding the 5xxx series aluminum alloy wire.

[0064] Preparation of aluminum alloy parts: The solution treatment temperature was 472°C and the time was 4 hours; the aging temperature was 157°C and the time was 7 hours, and finally the aluminum alloy parts were obtained.

[0065] Example 3

[0066] The difference from Example 1 lies in the preparation of the 5xxx series aluminum alloy wire: The aluminum alloy raw materials were proportioned by mass percentage as follows: 4.8% Mg, 2.5% Zn, 0.3% Mn, 0.20% Sc, 0.15% Zr, 0.06% Fe, 0.03% Si, with the balance being Al. The homogenization heat treatment temperature was 473℃, ultimately yielding the 5xxx series aluminum alloy wire.

[0067] Preparation of aluminum alloy parts: The solution treatment temperature was 473°C and the time was 4 hours; the aging temperature was 155°C and the time was 8 hours, and finally the aluminum alloy parts were obtained.

[0068] Example 4

[0069] The difference from Example 1 lies in the preparation of the 5xxx series aluminum alloy wire: The aluminum alloy raw materials were proportioned by mass percentage as follows: 5.0% Mg, 2.7% Zn, 0.4% Mn, 0.22% Sc, 0.15% Zr, 0.08% Fe, 0.05% Si, with the balance being Al. The homogenization heat treatment temperature was 473℃. The bar stock was cold-rolled to obtain wire with a diameter of 4mm, followed by multiple passes of annealing, drawing, scraping, and cleaning to obtain the 5xxx series aluminum alloy wire.

[0070] Preparation of aluminum alloy parts: The solution treatment temperature was 473°C and the time was 4 hours; the aging temperature was 155°C and the time was 8 hours, and finally the aluminum alloy parts were obtained.

[0071] Example 5

[0072] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: by mass percentage, the aluminum alloy raw materials are proportioned as follows: 5.5% Mg, 3.0% Zn, 0.5% Mn, 0.25% Sc, 0.10% Zr, 0.07% Fe, 0.05% Si, with the balance being Al, to finally obtain the 5xxx series aluminum alloy wire, and ultimately the aluminum alloy parts.

[0073] Example 6

[0074] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: by mass percentage, the aluminum alloy raw materials are proportioned as follows: 5.8% Mg, 3.5% Zn, 0.6% Mn, 0.30% Sc, 0.10% Zr, 0.06% Fe, 0.04% Si, with the balance being Al, to finally obtain the 5xxx series aluminum alloy wire, and ultimately the aluminum alloy parts.

[0075] Example 7

[0076] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: by mass percentage, the aluminum alloy raw materials are proportioned as follows: 6.0% Mg, 3.8% Zn, 0.5% Mn, 0.32% Sc, 0.08% Zr, 0.06% Fe, 0.04% Si, with the balance being Al, to finally obtain the 5xxx series aluminum alloy wire, and ultimately the aluminum alloy parts.

[0077] Example 8

[0078] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: by mass percentage, the aluminum alloy raw materials are proportioned as follows: 5.7% Mg, 4.0% Zn, 0.8% Mn, 0.25% Sc, 0.05% Zr, 0.06% Fe, 0.04% Si, with the balance being Al, to finally obtain the 5xxx series aluminum alloy wire, and ultimately the aluminum alloy parts.

[0079] Example 9

[0080] The difference from Example 5 is that the total mass content of Sc and Zr elements is 0.35%, the mass ratio of Sc to Zr elements is 4:1, and finally 5xxx series aluminum alloy wire is obtained, and finally aluminum alloy parts are obtained.

[0081] Example 10

[0082] The difference from Example 5 is that the total mass content of Sc and Zr elements is 0.35%, and the mass ratio of Sc to Zr elements is 1.06:1, ultimately obtaining 5xxx series aluminum alloy wire, and finally obtaining aluminum alloy parts.

[0083] Example 11

[0084] The difference from Example 5 is that the total mass content of Sc and Zr elements is 0.35%, and the mass ratio of Sc to Zr elements is 0.75:1, ultimately yielding 5xxx series aluminum alloy wire and aluminum alloy parts.

[0085] Example 12

[0086] The difference from Example 5 is that the total mass content of Mg and Zn elements is 8.5%, the mass ratio of Mg to Zn elements is 1.5:1, and finally 5xxx series aluminum alloy wire is obtained, and finally aluminum alloy parts are obtained.

[0087] Example 13

[0088] The difference from Example 5 is that the total mass content of Mg and Zn elements is 8.5%, the mass ratio of Mg to Zn elements is 2.4:1, and finally 5xxx series aluminum alloy wire is obtained, and finally aluminum alloy parts are obtained.

[0089] Example 14

[0090] The difference from Example 5 is that the total mass content of Mg and Zn elements is 8.5%, the mass ratio of Mg to Zn elements is 1.43:1, and finally 5xxx series aluminum alloy wire is obtained, and finally aluminum alloy parts are obtained.

[0091] Example 15

[0092] The difference from Example 5 is that the total mass content of Mg and Zn elements is 9.0%, and the mass ratio of Mg to Zn elements is 1.57:1, ultimately obtaining 5xxx series aluminum alloy wire, and finally obtaining aluminum alloy parts.

[0093] Example 16

[0094] The difference from Example 5 is that the total mass content of Sc and Zr elements is 0.40%, and the mass ratio of Sc to Zr elements is 0.82:1, ultimately yielding 5xxx series aluminum alloy wire and aluminum alloy parts.

[0095] Example 17

[0096] The difference from Example 5 is that the homogenization heat treatment temperature in the preparation of 5xxx series aluminum alloy wire is 470°C, and 5xxx series aluminum alloy wire is finally obtained.

[0097] Preparation of aluminum alloy parts: The voltage of electric arc additive manufacturing is 12.0V, the current of electric arc additive manufacturing is 100A, the solution temperature is 470°C and the time is 8h; the aging temperature is 150°C and the time is 15h, and finally aluminum alloy parts are obtained.

[0098] Example 18

[0099] The difference from Example 5 is that the homogenization heat treatment temperature in the preparation of 5xxx series aluminum alloy wire is 475°C, and 5xxx series aluminum alloy wire is finally obtained.

[0100] Preparation of aluminum alloy parts: The voltage of electric arc additive manufacturing is 11.0V, the current of electric arc additive manufacturing is 96A, the solution temperature is 475°C and the time is 4h; the aging temperature is 162°C and the time is 5h, and finally aluminum alloy parts are obtained.

[0101] Comparative Example 1

[0102] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: The aluminum alloy raw materials were proportioned by mass percentage as follows: 3.8% Mg, 2.2% Zn, 0.5% Mn, 0.20% Sc, 0.10% Zr, 0.06% Fe, 0.04% Si, with the balance being Al. The homogenization heat treatment temperature was 470℃, ultimately yielding the 5xxx series aluminum alloy wire.

[0103] Preparation of aluminum alloy parts: The solution treatment temperature is 470°C and the time is 4h; the aging temperature is 155°C and the time is 8h, and finally aluminum alloy parts are obtained.

[0104] Comparative Example 2

[0105] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: The aluminum alloy raw materials were proportioned by mass percentage as follows: 4.6% Mg, 1.8% Zn, 0.3% Mn, 0.20% Sc, 0.10% Zr, 0.07% Fe, 0.05% Si, with the balance being Al. The homogenization heat treatment temperature was 472℃, ultimately yielding the 5xxx series aluminum alloy wire.

[0106] Preparation of aluminum alloy parts: The solution treatment temperature was 473°C and the time was 4 hours; the aging temperature was 155°C and the time was 8 hours, and finally the aluminum alloy parts were obtained.

[0107] Comparative Example 3

[0108] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: by mass percentage, the aluminum alloy raw materials are proportioned as follows: 7.2% Mg, 4.5% Zn, 0.5% Mn, 0.15% Sc, 0.12% Zr, 0.08% Fe, 0.05% Si, with the balance being Al, to finally obtain the 5xxx series aluminum alloy wire, and ultimately the aluminum alloy parts.

[0109] Comparative Example 4

[0110] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: by mass percentage, the aluminum alloy raw materials are proportioned as follows: 5.8% Mg, 3.8% Zn, 0.5% Mn, 0.04% Sc, 0.15% Zr, 0.07% Fe, 0.04% Si, with the balance being Al, to finally obtain the 5xxx series aluminum alloy wire, and ultimately the aluminum alloy parts.

[0111] Comparative Example 5

[0112] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: by mass percentage, the aluminum alloy raw materials are proportioned as follows: 5.5% Mg, 3.0% Zn, 0.3% Mn, 0.10% Sc, 0.04% Zr, 0.09% Fe, 0.05% Si, with the balance being Al, to finally obtain the 5xxx series aluminum alloy wire, and ultimately the aluminum alloy parts.

[0113] Comparative Example 6

[0114] The difference from Example 4 lies in the preparation of the 5xxx series aluminum alloy wire: by mass percentage, the aluminum alloy raw materials are proportioned as follows: 5.3% Mg, 3.5% Zn, 0.5% Mn, 0.30% Sc, 0.25% Zr, 0.08% Fe, 0.05% Si, with the balance being Al, to finally obtain the 5xxx series aluminum alloy wire, and ultimately the aluminum alloy parts.

[0115] Test method:

[0116] Average grain size test: Take metallographic samples, anodicly coat the samples, and observe the grain structure using a metallographic microscope. Calculate the average grain size using the intercept method according to the national standard GB / T 6394.

[0117] Volume fraction of Al3(Sc, Zr) nanoparticles: The distribution of Al3(Sc, Zr) particles in the alloy microstructure was observed using TEM, and the size and number of Al3(Sc, Zr) particles were statistically analyzed to calculate their volume fraction.

[0118] Mg 32 (Al, Zn) 49 Phase volume fraction: Mg in the alloy microstructure was observed using TEM. 32 (Al, Zn) 49 Phase distribution, statistical analysis of Mg 32 (Al, Zn) 49 The size and quantity of the phases are used to calculate their volume fraction.

[0119] Yield strength, tensile strength and elongation tests: Take a plate-shaped tensile specimen along the printing direction and perform tensile property tests in accordance with the "Metallic Materials - Test Methods and Requirements at Room Temperature" (GB / T 228.1-2021).

[0120] The test results for 5xxx series aluminum alloy wires are shown in Table 1. The microstructure and properties of the arc additively manufactured components in the printed state are shown in Table 2. The microstructure and properties of the heat-treated aluminum alloy parts are shown in Table 3.

[0121] Table 1

[0122]

[0123] Table 2

[0124]

[0125] Table 3

[0126]

[0127] As can be seen from the above, the content of Mg in Comparative Example 1 is relatively low, and the content of Zn in Comparative Example 2 is relatively low, resulting in lower strength of the arc additive manufacturing components and aluminum alloy parts.

[0128] In Comparative Example 3, the contents of Mg and Zn elements were both high. After arc additive manufacturing, there were too many eutectic phases in the microstructure, and they were difficult to completely dissolve after heat treatment, resulting in a low elongation rate of arc additive manufacturing.

[0129] The low Sc content in Comparative Example 4 and the low Zr content in Comparative Example 5 resulted in insufficient Al3(Sc, Zr) nanoparticles as heterogeneous nucleating agents to refine grains and suppress cracking during the arc additive manufacturing process. Consequently, the components manufactured by arc additive manufacturing had cracks in their microstructure and also exhibited low strength and elongation.

[0130] The high total amount of Sc and Zr in Comparative Example 6 resulted in the presence of primary Al3(Sc, Zr) phase particles in the microstructure of the arc additive manufacturing component. These particles were difficult to dissolve back into the microstructure, leading to poorer plasticity and reduced elongation of the alloy.

[0131] in, Figure 1 This is a surface morphology image of the 5xxx series aluminum alloy wire in Example 5. Figure 1 As can be seen, the surface of the 5xxx series aluminum alloy wire is smooth and free of cracks.

[0132] Figure 2 This is a metallographic diagram of the arc additive manufacturing component in Example 5, from... Figure 2 As can be seen, the components manufactured by electric arc additive manufacturing have a dense structure, no cracks, and very few pores.

[0133] Figure 3 This is a grain structure diagram of the arc additive manufacturing component in Example 5, from... Figure 3 As can be seen, the grains of the printed arc additive manufacturing components are small and uniformly distributed.

[0134] Figure 4 This is a SEM image of the aluminum alloy part in Example 5, from... Figure 4 As can be seen, the second-phase particles in the microstructure of the aluminum alloy parts are fully dissolved after heat treatment, which is conducive to the precipitation of the strengthening phase T.

[0135] Figure 5 The image shows the surface morphology of the 5xxx series aluminum alloy wire in Comparative Example 4. Figure 5 As can be seen, the surface of the 5xxx series aluminum alloy wire has a small number of defects such as pits and scratches.

[0136] Figure 6 This is a metallographic diagram of the arc additive manufacturing component in Comparative Example 4. Figure 6As can be seen, there are some microcracks in the microstructure of the arc additive manufacturing component, resulting in poor printing effect.

[0137] Figure 7 This is a grain structure diagram of the arc additive manufacturing component in Comparative Example 4. Figure 7 As can be seen from the data, the microstructure of the formed part is columnar crystal morphology with large grain size.

[0138] Figure 8 The image shows the SEM image of the aluminum alloy part in Comparative Example 4. Figure 8 As can be seen, after heat treatment, the second phase in the microstructure of the aluminum alloy part is fully dissolved, which is conducive to the precipitation of the strengthening phase T.

[0139] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0140] The 5xxx series aluminum alloy wire of this application incorporates Sc and Zr elements, with the total mass of Sc and Zr elements controlled within the aforementioned range. During the arc additive manufacturing process, Al3(Sc, Zr) multi-component composite nanoparticles are formed, acting as heterogeneous nucleation elements, thereby refining the grain size and inhibiting cracking. Simultaneously, the addition of a small amount of Mn element to the 5xxx series alloy wire enables the formation of Al6Mn nanoparticles during the arc additive manufacturing process, also acting as heterogeneous nucleation elements, further refining the grain size. The addition of the aforementioned amount of Zn element allows the formation of the T phase (Mg). 32 (Al, Zn) 49 The formation of the T phase enhances the mechanical properties of 5xxx series aluminum alloy wires by controlling the mass content of Al3(Sc, Zr) nanoparticles within the aforementioned range. This allows the tensile strength of 5xxx series aluminum alloy wires after additive manufacturing to reach ≥320MPa, while simultaneously suppressing cracking. The formation of the T phase further enhances the tensile strength of the additively manufactured aluminum alloy after heat treatment to reach ≥450MPa, thus meeting the mechanical property requirements of aluminum alloys in aerospace and other fields.

[0141] The above are merely embodiments of the present invention and are not intended to limit the invention. Those skilled in the art will recognize that the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A 5xxx series aluminum alloy wire, characterized in that, The 5xxx series aluminum alloy wire comprises the following elements by weight percentage: 4.0~6.0% Mg element; 2.0~4.0% Zn element; The composition comprises: 0.1-0.8% Mn; 0.05-0.40% Sc; 0.05-0.25% Zr; Fe ≤0.10%; Si ≤0.08%; total unavoidable impurities ≤0.15%; and the balance being Al. The total mass content of the Sc and Zr elements is 0.25-0.50%. The volume fraction of Al3(Sc, Zr) nanoparticles in the 5xxx series aluminum alloy wire is 0.2~0.55%.

2. The 5xxx series aluminum alloy wire according to claim 1, characterized in that, The 5xxx series aluminum alloy wire comprises the following elements by weight percentage: 4.5~6.0% of the Mg element; 2.5% to 4.0% of the Zn element; 0.1% to 0.5% of the Mn element; 0.08% to 0.35% of the Sc element; The Zr element is 0.07-0.20%; the Fe element is 0.03-0.10%; the Si element is 0.02-0.08%; the total content of unavoidable impurities is ≤0.15%; and the balance is Al.

3. The 5xxx series aluminum alloy wire according to claim 1 or 2, characterized in that, The mass ratio of Sc to Zr is 1~4:1; and / or the mass ratio of Mg to Zn is 1.5~2.4:1; And / or, the diameter of the 5xxx series aluminum alloy wire is 1.0~1.6mm.

4. A method for preparing the 5xxx series aluminum alloy wire according to any one of claims 1 to 3, characterized in that, The preparation method includes: Step S1: After the raw materials corresponding to the aluminum alloy are batched, they are successively smelted, refined, cast, homogenized heat treatment and hot rolled to obtain bars; Step S2: The bar is subjected to multiple annealing, drawing and wire scraping processes to obtain the 5xxx series aluminum alloy wire.

5. The preparation method according to claim 4, characterized in that, Step S1 further includes: Step S11: After the pure aluminum ingot is first melted, Al-Sc master alloy, Al-Zr master alloy, Al-Mn master alloy and pure zinc ingot are added for a second melt to obtain the first alloy liquid; Step S12: After the first alloy liquid is stirred, allowed to stand and refined by degassing in sequence, pure magnesium ingots are added for a third melting to obtain the second alloy liquid. Step S13: The second alloy liquid is subjected to the second degassing refining and the casting in sequence to obtain an ingot; the ingot is subjected to the homogenization heat treatment, cooling and hot rolling in sequence to obtain the bar. Wherein, the first melting temperature is 840~860℃, and the first melting time is 2~6h; the second melting temperature is 780~800℃, and the second melting time is 1~3h; the third melting temperature is 750~770℃, and the third melting time is 10~20min; The temperature of the first degassing and refining process is 720~760℃, and the time for the first degassing and refining process is 15~25min; the temperature of the second degassing and refining process is 710~750℃, and the time for the second degassing and refining process is 15~25min.

6. The preparation method according to claim 4 or 5, characterized in that, In step S1, the temperature of the homogenization heat treatment is 470~473℃, and the time of the homogenization heat treatment is 24~30h. And / or, the hot rolling includes hot roughing and hot finishing performed sequentially, the hot roughing having a processing rate of 90-98%, the hot finishing having a processing rate of 80-85%, and the hot rolling temperature being 440-450°C; And / or, step S2 further includes: cold rolling the bar to obtain cold-rolled wire, and sequentially subjecting the cold-rolled wire to the multi-pass annealing, drawing, and wire scraping to obtain the 5xxx series aluminum alloy wire; and / or, the temperature of the multi-pass annealing is 430~450℃.

7. A method for preparing an aluminum alloy part, characterized in that, The preparation method includes: The 5xxx series aluminum alloy wire according to any one of claims 1 to 3 is subjected to electric arc additive manufacturing to obtain an electric arc additive manufacturing component; the electric arc additive manufacturing component is subjected to heat treatment to obtain the aluminum alloy part.

8. The preparation method according to claim 7, characterized in that, The voltage of the electric arc additive manufacturing is 12.0~15.0V, and the current of the electric arc additive manufacturing is 100~150A; And / or, the volume fraction of Al3(Sc, Zr) nanoparticles in the arc additive manufacturing component is 0.15~0.35%; the volume fraction of Mg in the arc additive manufacturing component is... 32 (Al, Zn) 49 The volume fraction of the phase is 1.8% to 3.3%; And / or, the density of the arc additive manufacturing component is ≥99%; the average grain size of the arc additive manufacturing component is 10~30μm; the yield strength of the arc additive manufacturing component is ≥220MPa; the tensile strength of the arc additive manufacturing component is ≥320MPa; and the elongation of the arc additive manufacturing component is ≥8%.

9. The preparation method according to claim 8, characterized in that, The heat treatment includes sequential solution treatment and aging; wherein the solution treatment temperature is 470~473℃, and the solution treatment time is 4~8h; the aging temperature is 150~160℃, and the aging time is 5~15h; the Mg content in the aluminum alloy part... 32 (Al, Zn) 49 The volume fraction of the phase is 3.5~5.0%; And / or, the aluminum alloy part has a yield strength ≥350MPa, a tensile strength ≥450MPa, and an elongation ≥10%.

10. An aluminum alloy part, characterized in that, The aluminum alloy part is prepared by the preparation method according to any one of claims 7 to 9.

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