Mirror surface aluminum alloy and preparation method and application thereof

Abstract

The invention provides a mirror surface aluminum alloy as well as a preparation method and application thereof. The preparation method comprises the following steps: preparing raw materials according to components of the mirror surface aluminum alloy, and preparing the raw materials into a cast ingot; carrying out homogenization treatment on the cast ingot to obtain a homogenized blank; carrying out hot rolling treatment on the homogenized blank to obtain a first plate; the first plate is subjected to cold rolling treatment, and a second plate is obtained; the second plate is subjected to mirror surface rolling treatment, and a third plate is obtained; and the third plate is subjected to annealing treatment, and the mirror surface aluminum alloy is obtained. The production process is simplified, key process parameters are optimized, an intermediate annealing process is canceled, low-temperature hot rolling starting and high-temperature hot rolling finishing technologies are combined, and fine cold rolling and mirror surface rolling control is assisted, so that the production cost is reduced on the premise that the optical performance and the surface quality of mirror surface aluminum are guaranteed. The production period is obviously shortened; and the energy consumption is reduced.

Description

Technical Field

[0001] This invention relates to the field of alloy technology, and more specifically, to a mirror-finish aluminum alloy, its preparation method, and its application. Background Technology

[0002] The high-end automotive, high-end electronic equipment, and architectural decoration industries are increasingly demanding higher surface quality and optical performance from aluminum alloy materials. Mirror aluminum, as an aluminum alloy product with high gloss, excellent reflectivity, good corrosion resistance, and decorative properties, is widely used in these fields. Mirror aluminum not only enhances the aesthetic appeal of products but also, due to its excellent processing performance and environmental adaptability, has become an indispensable material in modern industrial design and manufacturing. However, the complex and costly production process of traditional mirror aluminum limits its wider application and market competitiveness.

[0003] The production process of conventional mirror-finish aluminum typically involves multiple stages: casting, homogenization, hot rolling, cold rolling, intermediate annealing, mirror rolling, and final annealing. Intermediate annealing aims to eliminate work hardening during cold rolling and improve the material's plasticity and processing properties. However, this step increases production time and energy consumption, extending the overall production cycle and raising costs. Furthermore, the temperature control during hot and cold rolling, the cooling method of the hot-rolled coil, and the technical requirements of mirror rolling all directly impact the surface quality and performance of the final product.

[0004] With the continuous development of aluminum alloy processing technology, the short-process production method for high-brightness anodized mirror aluminum is gradually becoming a research hotspot in the industry. It not only meets the stringent requirements of the high-end market for the surface quality and optical properties of aluminum alloy materials, but also effectively reduces production costs and improves production efficiency, which is of great significance for promoting the application of aluminum alloy materials in more fields. However, how to further optimize the production process, reduce energy consumption, and minimize environmental pollution while ensuring product quality remains a significant challenge for aluminum alloy processing technology.

[0005] Therefore, how to provide a method for preparing mirror-finish aluminum alloys, so as to obtain mirror-finish aluminum alloys with higher surface quality in a shorter process, is one of the technical problems that need to be solved in this field. Summary of the Invention

[0006] The main objective of this invention is to provide a mirror-finish aluminum alloy, its preparation method, and its application, in order to solve the problem that it is difficult to prepare a mirror-finish aluminum alloy with high surface quality through a short process in the prior art.

[0007] To achieve the above objectives, a first aspect of the present invention provides a method for preparing a mirror-finish aluminum alloy, comprising: step S1, preparing raw materials according to the composition of the mirror-finish aluminum alloy and preparing the raw materials into an ingot; step S2, homogenizing the ingot to obtain a homogenized billet; step S3, hot rolling the homogenized billet to obtain a first plate; the initial rolling temperature of the hot rolling treatment is 420℃~480℃, and the final rolling temperature is 300℃~340℃; step S4, cold rolling the first plate to obtain a second plate; the total deformation of the cold rolling treatment is 30%~70%, and the cold rolling treatment does not include heat treatment; step S5, mirror rolling the second plate to obtain a third plate; the surface roughness Ra of the rolls used for mirror rolling is 0.01μm~0.05μm; and step S6, annealing the third plate to obtain a mirror-finish aluminum alloy.

[0008] Further, in step S1, the ingot preparation process includes: melting the raw materials into a melt, and casting the melt into an ingot; the melting temperature is 720℃~760℃, and the casting temperature is 680℃~720℃; and / or, by weight percentage, the mirror aluminum alloy includes 0%~0.01% Mg, 0.08%~0.13% Fe, 0%~0.01% Cu, 0.06%~0.12% Si, 0%~0.04% impurity elements, and the remainder is Al.

[0009] Furthermore, in step S2, the heat preservation temperature for homogenization treatment is 480℃~500℃, and the heat preservation time is 2h~12h.

[0010] Further, in step S3, the temperature difference between the initial rolling temperature and the final rolling temperature is 100℃~130℃; and / or, the total deformation of the hot rolling treatment is 98%~99.5%; and / or, the number of hot rolling passes is 15~22, and the rolling speed of the last pass is 3.0m / min~4.0m / min.

[0011] Furthermore, in step S4, the rolling speed of the cold rolling process is 100m / min to 200m / min.

[0012] Furthermore, in step S5, the mirror rolling process involves 2 to 3 rolling passes, and the deformation per pass is 10% to 30%.

[0013] Furthermore, in step S6, the holding temperature for the annealing treatment is 200℃~260℃, and the holding time is 1h~24h.

[0014] A second aspect of the present invention provides a mirror-finish aluminum alloy, which is prepared by the above-described method for preparing mirror-finish aluminum alloy.

[0015] Furthermore, the surface roughness of the mirror-finished aluminum alloy is 45nm~60nm; and / or, the cube texture ratio of the mirror-finished aluminum alloy is 0.6%~4%; and / or, at 0.2A / dm 2 ~0.4A / dm 2 Anodizing is performed on mirror aluminum alloy at a current density to obtain anodized mirror aluminum alloy; the gloss of the anodized mirror aluminum alloy is 400GU~500GU.

[0016] A third aspect of the present invention provides an application of the above-mentioned mirror aluminum alloy as a functional and / or decorative material in the fields of aerospace, optics, architecture, transportation, and electronics and electrical engineering.

[0017] By applying the technical solution of this invention, the intermediate annealing process is eliminated by simplifying the production process and optimizing key process parameters. Combined with low-temperature hot rolling start-up and high-temperature hot rolling finish-up technologies, and supplemented by precise cold rolling and mirror rolling control, the production cycle is significantly shortened and energy consumption is reduced while ensuring the optical performance and surface quality of mirror aluminum. This achieves efficient, low-cost, and short-process production of high-brightness anodized mirror aluminum. Detailed Implementation

[0018] 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 embodiments.

[0019] As described in the background art, there is a problem in the prior art that it is difficult to obtain mirror-finish aluminum alloys with high surface quality through a short process. To solve the above-mentioned technical problem, the first aspect of the present invention provides a method for preparing a mirror-finish aluminum alloy, comprising: step S1, preparing raw materials according to the composition of the mirror-finish aluminum alloy and preparing the raw materials into ingots; step S2, homogenizing the ingots to obtain homogenized billets; step S3, hot-rolling the homogenized billets to obtain a first sheet; the initial rolling temperature of the hot rolling treatment is 420℃~480℃, and the final rolling temperature is 300℃~340℃; step S4, cold-rolling the first sheet to obtain a second sheet; the total deformation of the cold rolling treatment is 30%~70%, and the cold rolling process does not include heat treatment; step S5, mirror-finishing the second sheet to obtain a third sheet; the surface roughness Ra of the rolls used in the mirror-finishing treatment is 0.01μm~0.05μm; and step S6, annealing the third sheet to obtain a mirror-finish aluminum alloy.

[0020] This invention, by eliminating the intermediate annealing process and combining low-temperature hot rolling initial rolling and high-temperature hot rolling final rolling technologies, supplemented by precise cold rolling and mirror-finish rolling control, achieves the goal of significantly shortening the production cycle and reducing energy consumption while ensuring the optical properties and surface quality of mirror-finish aluminum. In the above-mentioned preparation process, especially the setting of the initial rolling temperature (more preferably 420℃~450℃) and the final rolling temperature (more preferably 300℃~320℃), allows for more precise control of the material's microstructure evolution, achieving significant results, particularly in suppressing recrystallization. Specifically, a suitable initial rolling temperature helps slow down the recrystallization process, forming a fine and uniform grain structure, retaining more deformation energy, and enabling the material to exhibit higher hardness and strength in subsequent cold rolling, thereby ensuring dimensional accuracy and surface quality during mirror-finish rolling. The hot rolling final rolling temperature above the recrystallization temperature utilizes the natural cooling process during material curling and storage to achieve spontaneous static recrystallization annealing, releasing some of the stored energy and avoiding excessive energy accumulation under subsequent high cold rolling rates, which would narrow the annealing process window for the finished product. In summary, the scientific setting of the initial and final rolling temperatures in the hot rolling process provided by this invention enables the material to form a stable and uniform microstructure during the hot rolling stage. This paves the way for the cold rolling process, eliminating the need for intermediate annealing. Traditionally, intermediate annealing in cold rolling is primarily used to alleviate work hardening and restore plasticity. However, in this invention, because the microstructure of the material is effectively controlled during the hot rolling stage, excessive work hardening is avoided. Therefore, heat treatment is no longer required during cold rolling, greatly simplifying the production process, reducing energy consumption, accelerating production pace, and significantly improving production efficiency.

[0021] In the recrystallization annealing process of aluminum alloys and other face-centered cubic alloys, a cube texture can be easily formed through preferred nucleation and selective growth of cube-oriented nuclei, with the ideal crystallographic orientation being {100}. <001> Generally speaking, aggregated and uneven cube textures can lead to noticeable streaks after anodizing of alloy sheets, thus affecting their gloss. The preparation method provided by this invention increases the deformation during cold rolling before annealing, which helps eliminate the cube texture generated during hot rolling and self-annealing, reducing the proportion of cube texture after annealing, thereby improving the gloss of the finished product and reducing streaks.

[0022] Based on this, the process is further coordinated with casting, cold rolling, mirror rolling and finished product annealing. At the same time, the precise control of each parameter in the cold rolling and mirror rolling process is restricted accordingly. This effectively manages the evolution of the material's microstructure and surface morphology, avoids the extra time and energy consumption caused by multiple annealing in traditional processes, and effectively ensures the surface quality and performance consistency of the finished product.

[0023] Furthermore, in order to more effectively improve the uniformity and purity of the ingot, promote grain refinement, thereby enhancing the hardness and wear resistance of the final mirror-finished aluminum alloy, reducing surface defects, and improving its surface smoothness and gloss, the preferred ingot preparation process in step S1 includes: melting the raw materials into a melt and casting the melt into an ingot; the melting temperature is 720℃~760℃, and the casting temperature is 680℃~720℃.

[0024] In several typical embodiments, the mirror-finish aluminum alloy comprises, by weight percentage, 0%–0.01% Mg, 0.08%–0.13% Fe, 0%–0.01% Cu, 0.06%–0.12% Si, 0%–0.04% impurity elements, and the remainder Al. The low content of Mg and Cu optimizes the strength and hardness of the resulting mirror-finish aluminum alloy, more effectively reducing the negative impact of excessive alloying on surface quality. Adjusting the ratio of Fe and Si further optimizes the stability of the microstructure, promotes the formation of a uniform lattice, and results in a superior mirror finish. Based on this, in order to ensure that the obtained mirror-finish aluminum alloy can meet the requirements of high surface quality while more effectively maintaining good processing performance and mechanical properties, the mirror-finish aluminum alloy is further optimized to include 0.005%~0.01% Mg, 0.10%~0.13% Fe, 0.008%~0.01% Cu, 0.10%~0.12% Si, 0.02%~0.04% impurity elements, and the remainder being Al, by weight percentage.

[0025] In practical applications, the impurity elements in the aforementioned mirror-finish aluminum alloys are generally Cr, V, and B, etc.

[0026] In step S2, the stability and consistency of the obtained billet are improved by homogenization treatment. The preferred holding temperature for homogenization treatment is 480℃~500℃ (more preferably 490℃~500℃), and the holding time is 2h~12h, which can further promote the full diffusion of alloying elements, more significantly eliminate component segregation and partial dissolution of the second phase, and form a more stable microstructure. The lower homogenization temperature can effectively prevent grain growth, thereby obtaining a mirror aluminum alloy with higher surface quality after subsequent rolling.

[0027] In the hot rolling process of step S3, the temperature difference between the initial rolling temperature and the final rolling temperature is preferably 100℃~130℃, so as to better balance the deformation strengthening and dynamic recrystallization effect of the plate during the hot rolling process, reduce the dynamic recrystallization during the hot rolling process, form a better microstructure, better support the subsequent cold rolling and mirror rolling processes, promote its better ductility and surface integrity during the cold rolling process, and finally present a more uniform and consistent high-quality mirror effect.

[0028] Furthermore, the total deformation of the hot rolling process is preferably 98% to 99.5%, which generates more dislocations and subgrain boundaries inside the plate. These micro-defects are transformed into fine grains and a uniform microstructure during the subsequent cooling and annealing process, thereby significantly enhancing the surface quality of the resulting mirror-finish aluminum alloy.

[0029] In several typical implementations, it is preferred that the hot rolling process consists of 15 to 22 passes, with the final pass having a rolling speed of 3.0 m / min to 4.0 m / min. This optimal final pass rolling speed promotes a smoother hot rolling process, reduces dynamic recrystallization caused by excessively slow speeds, and facilitates further grain refinement. This provides a more ideal substrate for cold rolling and mirror-finish rolling, resulting in a smooth, flawless final product with higher levels of gloss and reflectivity.

[0030] In step S4: the preferred rolling speed for cold rolling is 100m / min to 200m / min, so as to more precisely control the deformation of the sheet during the cold rolling process, improve the flatness and smoothness of the surface of the obtained cold-rolled sheet, and lay a better foundation for subsequent mirror rolling.

[0031] To further improve the surface gloss and reflectivity of the obtained mirror-finished aluminum alloy, in step S5, the mirror rolling process is preferably performed in 2 to 3 passes, with a deformation of 10% to 30% per pass. In several typical embodiments, it is preferred to use rolls with a Ra of 0.04 μm to 0.05 μm to sequentially perform a first pass of mirror rolling with a deformation of 20% to 30% (more preferably 20% to 25%) and a second pass of mirror rolling with a deformation of 15% to 20% (more preferably 15% to 18%) on the second sheet material. This allows for more refined surface treatment of the sheet material, further optimization of its surface microstructure, and a more significant improvement in surface smoothness and reflectivity, resulting in a higher quality third sheet material.

[0032] Because the deformation rate of the sheet metal is relatively large after multiple rolling processes, resulting in high energy storage, in order to more effectively suppress complete recrystallization and grain growth, in step S6, the holding temperature for annealing is preferably set at 200℃~260℃, and the holding time is preferably set at 1h~24h. Based on this, for precise control of stress release and microstructure stability within the sheet metal at this stage, the holding temperature for annealing is further preferably set at 240℃~260℃, and the holding time is preferably set at 1h~2h, in order to better maintain the microstructure of the resulting mirror-finish aluminum alloy, more effectively suppress excessive grain growth, and ultimately further improve its strength and surface quality.

[0033] A second aspect of the present invention provides a mirror-finish aluminum alloy, which is prepared by the above-described method for preparing mirror-finish aluminum alloy. Due to the aforementioned preparation process, and by precisely controlling the hot rolling, cold rolling, and mirror rolling processes, the resulting mirror-finish aluminum alloy exhibits higher surface quality, optical properties, and processing performance under conditions requiring a shorter preparation time.

[0034] It should be noted that due to the complex structural changes and crystal formation during the preparation process, and the limitations of the alloy material field and existing testing and characterization methods, it is difficult to perform a comprehensive quantitative characterization of the complex microstructure and metallographic features of the obtained mirror aluminum alloy. However, the performance test results have already shown that the mirror aluminum alloy obtained by this invention has higher surface quality, especially lower roughness, higher reflectivity and gloss, and better surface consistency after anodizing.

[0035] In several preferred embodiments, the surface roughness of the mirror-finished aluminum alloy is 45nm~60nm; and / or, the cube texture ratio of the mirror-finished aluminum alloy is 0.6%~4%; and / or, at 0.2A / dm 2 ~0.4A / dm 2 Anodizing was performed on the mirror aluminum alloy at a specific current density to obtain anodized mirror aluminum alloy; the gloss of the anodized mirror aluminum alloy was 400 GU~500 GU. That is to say, the mirror aluminum alloy prepared by this invention has lower surface roughness, higher reflectivity and gloss, and its surface is extremely smooth and flat, while possessing excellent optical reflection properties. Furthermore, after anodizing surface treatment, it can maintain high gloss, and its adaptability and durability in complex environments are also significantly improved.

[0036] A third aspect of this invention provides an application of the aforementioned mirror-finish aluminum alloy as a functional and / or decorative material in the aerospace, optics, architecture, transportation, and electronics and electrical fields. The mirror-finish aluminum alloy prepared by this invention, with its excellent surface finish, high reflectivity, high gloss, and surface consistency after anodizing, can meet the needs of various high-end application fields.

[0037] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0038] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0039] Example 1

[0040] A method for preparing mirror-finish aluminum alloy:

[0041] The composition of the prepared mirror aluminum alloy is: Al: 99.693%, Mg: 0.008%, Fe: 0.13%, Cu: 0.009%, Si: 0.12%, and other impurity elements (such as Cr, V, B): 0.04%.

[0042] (1) Melting and casting process: Aluminum ingots, magnesium ingots, scrap, intermediate alloys, and metal additives are used for batching and added to a melting furnace for melting at a melting temperature of 760℃. After melting, the materials are refined, stirred, and slag is removed. Then, the materials are transferred to a holding furnace for further refining and settling for 20 minutes before casting begins. The casting process uses online degassing and slag removal equipment for degassing and filtration, and grain refiners are added. The materials are then cast into flat ingots in a semi-continuous casting equipment at a casting temperature of 720℃.

[0043] (2) The obtained ingot is homogenized at a temperature of 500°C for 12 hours to obtain a homogenized billet.

[0044] (3) The obtained homogenized billet is hot-rolled to obtain the first plate. The initial rolling temperature of the hot rolling process is 420℃, and the final rolling temperature is 300℃ (i.e., the temperature difference between the initial rolling temperature and the final rolling temperature is 120℃). The hot rolling process is carried out in 22 passes, and the rolling speed of the last pass of the hot finishing rolling is controlled at 3.2m / min. The total deformation of the hot rolling process is 99.5%.

[0045] (4) The first plate obtained by hot rolling is subjected to cold rolling to obtain the second plate; the rolling speed of the cold rolling process is 200 m / min and the total deformation is 30%. At the same time, no heat treatment is involved in the plate during the cold rolling process.

[0046] (5) Using a roll with Ra of 0.05 μm, the second plate obtained by cold rolling is subjected to a first pass of mirror rolling with a deformation of 20% and a second pass of mirror rolling with a deformation of 16% to obtain the third plate.

[0047] (6) Annealing of finished product: cleaning before annealing, annealing temperature 260℃, holding for 1 hour, air cooling after removal from the furnace to obtain mirror aluminum alloy.

[0048] Example 2

[0049] A method for preparing mirror-finish aluminum alloy:

[0050] The only difference between this embodiment and embodiment 1 is that the heat preservation temperature for homogenization in step (2) is changed to 480°C and the heat preservation time is changed to 15h.

[0051] In this embodiment, the homogenization temperature is slightly lower than that in Example 1, the grain size is reduced, and therefore the cube texture is slightly increased, the gloss is slightly improved, and the roughness is slightly reduced.

[0052] Example 3

[0053] A method for preparing mirror-finish aluminum alloy:

[0054] The only difference between this embodiment and embodiment 1 is that the heat preservation temperature for homogenization in step (2) is changed to 550°C and the heat preservation time is changed to 10h.

[0055] In this embodiment, the homogenization temperature is slightly higher than that in Example 1, the grain size is larger, the gloss is correspondingly slightly lower, and slight streaks appear on the surface after anodizing.

[0056] Example 4

[0057] A method for preparing mirror-finish aluminum alloy:

[0058] The only difference between this embodiment and embodiment 1 is that the initial rolling temperature in step (3) is changed to 480°C, and the temperature difference between the initial rolling temperature and the final rolling temperature is changed to 180°C.

[0059] Example 5

[0060] A method for preparing mirror-finish aluminum alloy:

[0061] The only difference between this embodiment and embodiment 1 is that the final rolling temperature of the hot rolling process in step (3) is changed to 340°C, and the temperature difference between the initial rolling temperature and the final rolling temperature is changed to 80°C.

[0062] Example 6

[0063] A method for preparing mirror-finish aluminum alloy:

[0064] The only difference between this embodiment and embodiment 1 is that the rolling speed of the last pass in the multi-pass hot rolling process in step (3) is changed to 2.0 m / min.

[0065] Example 7

[0066] A method for preparing mirror-finish aluminum alloy:

[0067] The only difference between this embodiment and embodiment 1 is that the rolling speed of the last pass in the multi-pass hot rolling process in step (3) is changed to 5.0 m / min.

[0068] Example 8

[0069] A method for preparing mirror-finish aluminum alloy:

[0070] The only difference between this embodiment and embodiment 1 is that the rolling speed of the cold rolling process in step (4) is changed to 80m / min.

[0071] Example 9

[0072] A method for preparing mirror-finish aluminum alloy:

[0073] The only difference between this embodiment and embodiment 1 is that the rolling speed of the cold rolling process in step (4) is changed to 240m / min.

[0074] Example 10

[0075] A method for preparing mirror-finish aluminum alloy:

[0076] The only difference between this embodiment and embodiment 1 is that the mirror rolling process in step (5) is changed to one pass, and the deformation amount of this pass is 30%.

[0077] The mirror-finished aluminum alloy obtained in this embodiment has a higher roughness and a lower gloss compared to that in Embodiment 1.

[0078] Example 11

[0079] A method for preparing mirror-finish aluminum alloy:

[0080] The only difference between this embodiment and embodiment 1 is that the annealing temperature in step (6) is changed to 200°C and the holding time is changed to 2h.

[0081] The mirror-finished aluminum alloy obtained in this embodiment has a less uniform microstructure compared to that in Example 1, and exhibits a small number of streaks after anodizing.

[0082] Example 12

[0083] A method for preparing mirror-finish aluminum alloy:

[0084] The only difference between this embodiment and embodiment 1 is that the heat preservation temperature of the annealing process in step (6) is changed to 280°C.

[0085] In this embodiment, since the annealing temperature is slightly higher than that in Example 1, recrystallization occurs, the grains grow, the proportion of cube texture increases, and the gloss is slightly reduced.

[0086] Comparative Example 1

[0087] A method for preparing mirror-finish aluminum alloy:

[0088] The only difference between this comparative example and Example 1 is that the initial rolling temperature of the hot rolling process in step (3) is changed to 400°C and the final rolling temperature is changed to 270°C.

[0089] Although the proportion of Cube texture in the mirror-finished aluminum alloy obtained in this comparison is relatively low, the structure is uneven and there are obvious stripes after anodizing.

[0090] Comparative Example 2

[0091] A method for preparing mirror-finish aluminum alloy:

[0092] The only difference between this comparative example and Example 1 is that the initial rolling temperature of the hot rolling process in step (3) is changed to 500°C and the final rolling temperature is changed to 350°C.

[0093] The mirror-finished aluminum alloy obtained in this comparison has a significantly increased proportion of Cube texture, around 15%, resulting in poor machinability.

[0094] Comparative Example 3

[0095] A method for preparing mirror-finish aluminum alloy:

[0096] The only difference between this comparative example and Example 1 is that the total deformation of the cold rolling process in step (4) is changed to 20%.

[0097] The mirror-finished aluminum alloy obtained in this comparison also has a high proportion of cube texture and poor processing performance.

[0098] Comparative Example 4

[0099] A method for preparing mirror-finish aluminum alloy:

[0100] The only difference between this comparative example and Example 1 is that the total deformation of the cold rolling process in step (4) is changed to 80%.

[0101] Although the mirror-finished aluminum alloy obtained in this comparison has a lower cube texture, the finished product has uneven structure and obvious stripes.

[0102] Test methods

[0103] Surface roughness: obtained from confocal microscopy testing.

[0104] Cube texture percentage: obtained from electron backscatter diffraction (EBSD) measurements.

[0105] Gloss and surface striations of the sample after anodizing:

[0106] Using an H2SO4 solution with a mass concentration of 180 g / L as the electrolyte, and at 15–20 °C, the mirror-finished aluminum alloy samples obtained in each example and comparative example were subjected to a current density of 0.3 A / dm³. 2 Anodizing treatment for 10 minutes yields anodized mirror-finish aluminum alloy.

[0107] The surface gloss of the anodized sample was then measured using a gloss meter; surface stripes of the anodized sample were then observed.

[0108] The above tests were performed on the mirror-finished aluminum alloy samples obtained in each embodiment and comparative example, and the results are shown in Table 1.

[0109] Table 1

[0110]

[0111] As can be seen from the above description, the embodiments of the present invention, by eliminating the intermediate annealing process and combining low-temperature hot rolling initial rolling and high-temperature hot rolling final rolling technologies, supplemented by precise cold rolling and mirror rolling control, achieve the goal of significantly shortening the production cycle and reducing energy consumption while ensuring the optical properties and surface quality of mirror aluminum. The resulting mirror aluminum alloy has higher surface quality, especially lower roughness, higher reflectivity and gloss, and superior surface consistency after anodizing.

[0112] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those described herein.

[0113] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. 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 method for preparing a mirror-finish aluminum alloy, characterized in that, include: Step S1: Prepare raw materials according to the composition of the mirror aluminum alloy, and prepare the raw materials into ingots; Step S2: The ingot is homogenized to obtain a homogenized billet; Step S3: The homogenized billet is hot-rolled to obtain the first plate; the initial rolling temperature of the hot rolling process is 420℃~480℃, and the final rolling temperature is 300℃~340℃. Step S4: The first sheet is cold-rolled to obtain the second sheet; the total deformation of the cold rolling process is 30% to 70%, and the cold rolling process does not include heat treatment. Step S5: Perform mirror rolling on the second plate to obtain the third plate; the roughness Ra of the rolls used in the mirror rolling process is 0.01μm~0.05μm. Step S6: Anneal the third plate material to obtain the mirror-finish aluminum alloy.

2. The method for preparing mirror-finish aluminum alloy according to claim 1, characterized in that, In step S1, the preparation process of the ingot includes: melting the raw material into a melt and casting the melt into the ingot; the melting temperature is 720℃~760℃, and the casting temperature is 680℃~720℃. And / or, By weight percentage, the mirror-finished aluminum alloy contains 0%~0.01% Mg, 0.08%~0.13% Fe, 0%~0.01% Cu, 0.06%~0.12% Si, 0%~0.04% impurity elements, and the remainder is Al.

3. The method for preparing mirror-finish aluminum alloy according to claim 1 or 2, characterized in that, In step S2, the heat preservation temperature for homogenization treatment is 480℃~500℃, and the heat preservation time is 2h~12h.

4. The method for preparing mirror-finish aluminum alloy according to any one of claims 1 to 3, characterized in that, In step S3 The temperature difference between the initial rolling temperature and the final rolling temperature is 100℃~130℃; and / or, The total deformation of the hot rolling process is 98%~99.5%; and / or, The hot rolling process consists of 15 to 22 passes, with the last pass having a rolling speed of 3.0 m / min to 4.0 m / min.

5. The method for preparing mirror-finish aluminum alloy according to any one of claims 1 to 4, characterized in that, In step S4, the rolling speed of the cold rolling process is 100m / min to 200m / min.

6. The method for preparing mirror-finish aluminum alloy according to any one of claims 1 to 5, characterized in that, In step S5, the mirror rolling process involves 2 to 3 rolling passes, and the deformation per pass is 10% to 30%.

7. The method for preparing mirror-finish aluminum alloy according to any one of claims 1 to 6, characterized in that, In step S6, the holding temperature for the annealing treatment is 200℃~260℃, and the holding time is 1h~24h.

8. A mirror-finish aluminum alloy, characterized in that, The mirror-finish aluminum alloy is prepared by the method for preparing mirror-finish aluminum alloy according to any one of claims 1 to 7.

9. The mirror-finish aluminum alloy according to claim 8, characterized in that, The surface roughness of the mirror-finished aluminum alloy is 45nm~60nm; and / or, The cube texture of the mirror-finished aluminum alloy accounts for 0.6% to 4%; and / or, At 0.2A / dm 2 ~0.4A / dm 2 The mirror aluminum alloy is anodized at a current density to obtain an anodized mirror aluminum alloy. The gloss of the anodized mirror aluminum alloy is 400 GU~500 GU.

10. The application of the mirror-finished aluminum alloy of claim 8 or 9 as a functional and / or decorative material in the fields of aerospace, optics, architecture, transportation, and electronics and electrical engineering.

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