AlMgSi optical reflector material, preparation method and application

Abstract

The invention belongs to the technical field of non-ferrous metal material preparation, and particularly relates to an AlMgSi optical reflector material and a preparation method and application thereof.The AlMgSi optical reflector material comprises, by weight, 0.4%-0.7% of Si, smaller than or equal to 0.08% of Fe, 0.15%-0.30% of Cu, 0.8%-1.1% of Mg, smaller than or equal to 0.01% of Cr, smaller than or equal to 0.001% of Ti and the balance Al and inevitable impurities; the preparation method of the AlMgSi optical reflector material comprises the following steps that soaking, extrusion forming, solid solution treatment and aging treatment are sequentially conducted on an AlMgSi alloy ingot, and the AlMgSi optical reflector material is obtained; the soaking temperature ranges from 480 DEG C to 520 DEG C, and the extrusion temperature of extrusion forming ranges from 300 DEG C to 350 DEG C; the AlMgSi optical reflector material disclosed by the invention has high hardness and low surface roughness at the same time.

Description

Technical Field

[0001] This invention belongs to the field of non-ferrous metal material preparation technology, specifically relating to an AlMgSi optical mirror material, its preparation method, and its applications. Background Technology

[0002] Al-Mg-Si alloys, with their wide wavelength range, low density, and excellent machinability, have become a commonly used material for reflectors. With the rapid development of aluminum alloy material technology, their reflector applications are becoming increasingly widespread in various fields. Aluminum alloys can be rapidly machined into the matrix structure of reflectors using existing turning, milling, and grinding processes. Furthermore, diamond single-point turning can be used to process the mirror surface, directly obtaining a smooth surface that meets the imaging quality requirements of infrared optical systems. It can also economically and efficiently process aspherical surfaces, a characteristic that makes it highly favored in the field of engineering optics. In the cutting-edge field of aerospace weaponry, aluminum alloy reflectors, due to their lightweight advantage, are suitable for weight-sensitive equipment such as spacecraft, contributing to high-precision optical detection. In high-end civilian fields, they serve as core optical components in laser communication and precision instruments, ensuring efficient signal reflection. They are also prevalent in low-end civilian fields, such as security monitoring lenses and ordinary optical lenses, meeting public demand and demonstrating strong application potential through a balance of cost and performance.

[0003] Al-Mg-Si alloys offer significant advantages in optical properties. Compared to some other alloys, their matrix structure is more uniform, resulting in more stable reflectivity and surface finish after mirror polishing. However, some issues arise during single-point turning: elements such as Cr and Ti in the alloy readily form hard phases. These hard phases are highly hard and unevenly distributed, causing micro-chipping during turning, leading to micro-pits on the surface and compromising optical smoothness. Furthermore, dislocation pile-up easily occurs at the interface between the hard phase and the matrix, forming microcrack initiations, which still result in a decrease in surface roughness after polishing. Reducing or removing these elements can improve machinability, but it leads to coarse grains, resulting in insufficient material strength. This makes it difficult to balance high performance and machinability, limiting its application in precision optics. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an AlMgSi optical mirror material, a preparation method and an application, so that the AlMgSi optical mirror material has both high hardness and low surface roughness.

[0005] This invention provides an AlMgSi optical mirror material comprising the following weight percentage components: Si: 0.4-0.7%, Fe: ≤0.08%, Cu: 0.15-0.30%, Mg: 0.8-1.1%, Cr≤0.01%, Ti≤0.001%, with the remainder being Al and unavoidable impurities; The preparation method of the AlMgSi optical mirror material includes the following steps: the AlMgSi alloy ingot is subjected to homogenization, extrusion molding, solution treatment and aging treatment in sequence to obtain the AlMgSi optical mirror material; the homogenization temperature is 480-520℃, and the extrusion molding temperature is 300-350℃.

[0006] Preferably, the composition includes the following components by weight percentage: Si: 0.5-0.6%, Fe: ≤0.05%, Cu: 0.18-0.27%, Mg: 0.9-1.0%, Cr ≤0.01%, Ti ≤0.001%, and the remainder being Al and unavoidable impurities.

[0007] This invention provides a method for preparing the AlMgSi optical mirror material, comprising the following steps: subjecting an AlMgSi alloy ingot to homogenization, extrusion molding, solution treatment, and aging treatment in sequence to obtain the AlMgSi optical mirror material; wherein the homogenization temperature is 480-520℃, and the extrusion molding temperature is 300-350℃.

[0008] Preferably, the heat equalization time is 6-10 hours, and after heat equalization is completed, the temperature is cooled to room temperature.

[0009] Preferably, the cooling method to room temperature is water cooling.

[0010] Preferably, the extrusion ratio of the extrusion forming is 20-30.

[0011] Preferably, the solution temperature is 490-510℃ and the solution time is 20-40 min.

[0012] Preferably, the aging temperature of the aging treatment is 160-180℃, and the holding time is 4-8h.

[0013] Preferably, the AlMgSi alloy ingot is prepared by mixing the components, melting them at 730-750°C, adding a refining agent for refining, introducing a protective gas during the melting process, allowing it to stand after melting, removing slag, and casting to obtain the AlMgSi alloy ingot. Preferably, the refining agent is mk4357B.

[0014] Specifically, the preparation method for AlMgSi alloy ingots is as follows: Material preparation and calculation are performed according to the designed composition requirements. First, 99.92% aluminum ingots, aluminum-silicon master alloys, aluminum-copper master alloys, and magnesium ingots are added to a melting furnace and heated to 730-750℃. After complete melting, refining is carried out using a refining agent (MK4357B) at a temperature of 720-735℃. The refining process takes 8-12 minutes, using argon gas as the medium, with a refining agent addition ratio of 1 kg / 1 tAl. After refining, the mixture is allowed to stand for 5-10 minutes before slag removal, removing all floating slag from the surface of the molten aluminum. After these steps, the temperature of the molten aluminum is adjusted to 730±10℃, and after standing for 10-20 minutes, casting begins.

[0015] This invention provides an application of the AlMgSi optical mirror material, which is used to manufacture mirrors.

[0016] The beneficial effects of this invention are that it breaks through the design limitations of traditional Al-Mg-Si alloys by eliminating Cr and Ti elements to reduce the formation of hard phases from the source, fundamentally improving the machinability of single-point turning. Addressing the problem of coarse grains that easily arise after element removal, the invention employs ingot homogenization, controlling the homogenization temperature within a suitable range to control grain growth, followed by medium-low temperature extrusion. This utilizes plastic deformation to increase dislocation density, providing sufficient nucleation sites for recrystallization during subsequent solution treatment, achieving grain refinement. Subsequent aging promotes the uniform precipitation of strengthening phases, improving material strength while avoiding interference from hard phases. Ultimately, a balance between high performance and ease of machining is achieved, significantly optimizing single-point turning performance and structural strength, providing a new technical path for the efficient and precise manufacturing of Al-Mg-Si alloy mirrors. Detailed Implementation

[0017] Example 1 An AlMgSi optical mirror material is prepared with the following composition: Si: 0.56%, Fe: 0.05%, Cu: 0.24%, Mg: 0.95%, free of Cr and Ti, with the remainder being Al and unavoidable impurities. The preparation process is as follows: The first step involves calculating and preparing the materials according to the designed composition requirements. First, 99.92% aluminum ingots, aluminum-silicon master alloy, aluminum-copper master alloy, and magnesium ingots are added to the melting furnace and heated to 740℃. After complete melting, a refining agent (MK4357B) is used for refining at 732℃. The refining process lasts 10 minutes, using argon as the medium gas, with an agent addition ratio of 1 kg / 1 tAl. After refining, the mixture is allowed to stand for 8 minutes before skimming off any slag floating on the surface of the molten aluminum. After these steps, the aluminum melt temperature is adjusted to 730℃, and after standing for 15 minutes, casting begins to form ingots. The second step is to perform a homogenization heat treatment on the billet at a temperature of 500℃ for 8 hours, followed by water cooling. The third step is extrusion molding, with an extrusion temperature of 320℃ and an extrusion ratio of 25.

[0018] The fourth step is solution treatment and aging. The solution temperature is 500℃ and the holding time is 30 minutes. The aging temperature is 170℃ and the holding time is 6 hours.

[0019] Example 2 An AlMgSi optical mirror material is prepared with the following composition: Si: 0.54%, Fe: 0.05%, Cu: 0.21%, Mg: 0.90%, free of Cr and Ti, with the remainder being Al and unavoidable impurities. The preparation process is as follows: The first step involves calculating and preparing the materials according to the designed composition requirements. First, 99.92% aluminum ingots, aluminum-silicon master alloys, aluminum-copper master alloys, and magnesium ingots are added to the melting furnace and heated to 740℃. After complete melting, a refining agent (MK4357B) is used for refining at 730℃. The refining process lasts 10 minutes, using argon as the medium gas, with an agent addition ratio of 1 kg / 1 tAl. After refining, the mixture is allowed to stand for 8 minutes before skimming off any floating slag from the surface of the molten aluminum. After these steps, the aluminum melt temperature is adjusted to 730℃, and after standing for 15 minutes, casting begins to form ingots. The second step is to perform a homogenization heat treatment on the billet at a temperature of 490℃ for 8 hours, followed by water cooling. The third step is extrusion molding, with an extrusion temperature of 330℃ and an extrusion ratio of 25.

[0020] The fourth step is solution treatment and aging. The solution temperature is 500℃ and the holding time is 30 minutes. The aging temperature is 170℃ and the holding time is 6 hours.

[0021] Comparative Example 1

[0022] Compared with Comparative Example 1, the difference is that the ingredients are: Si: 0.54%, Fe: 0.05%, Cu: 0.21%, Mg: 0.90%, Cr: 0.20%, Ti: 0.03%, with the remainder being Al and unavoidable impurities. Everything else is the same as in Example 2.

[0023] Comparative Example 2

[0024] Compared with Example 2, the difference is that the homogenization temperature in the second step is 550°C, while the rest is the same as Example 2.

[0025] Comparative Example 3

[0026] Compared with Example 2, Comparative Example 3 differs in that the homogenization temperature in the second step is 500°C and the extrusion temperature in the third step is 390°C. Otherwise, they are the same as Example 2.

[0027] Comparative Example 4

[0028] Compared with Example 2, Comparative Example 4 differs in that the ingredients are: Si: 0.54%, Fe: 0.05%, Cu: 0.21%, Mg: 0.90%, Cr: 0.20%, Ti: 0.03%, with the remainder being Al and unavoidable impurities.

[0029] The second step's heat treatment temperature is 550°C, and the third step's extrusion temperature is 430°C. The rest is the same as in Example 2.

[0030] Comparative Example 5

[0031] Compared with Comparative Example 5, the difference is that the ingredients are Si: 0.56%, Fe: 0.06%, Cu: 0.23%, Mg: 0.92%, Ti: 0.03%, and the rest are Al and unavoidable impurities.

[0032] The second step's heat treatment temperature is 500°C, and the third step's extrusion temperature is 390°C. The rest is the same as in Example 2.

[0033] Comparative Example 6

[0034] Compared with Comparative Example 6, the difference is that the ingredients are Si: 0.58%, Fe: 0.05%, Cu: 0.22%, Mg: 0.96%, Cr: 0.20%, and the rest are Al and unavoidable impurities.

[0035] The second step's heat treatment temperature is 550°C, and the third step's extrusion temperature is 430°C. The rest is the same as in Example 2.

[0036] The materials prepared by the above methods were tested for hardness and then subjected to single-point diamond precision turning with the same processing parameters. The surface roughness was tested, and the results are shown in Table 1.

[0037] Table 1

[0038] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of one or more embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0039] One or more embodiments in this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this application should be included within the protection scope of this application.

Claims

1. An AlMgSi optical mirror material, characterized in that, It includes the following components by weight percentage: Si: 0.4-0.7%, Fe: ≤0.08%, Cu: 0.15-0.30%, Mg: 0.8-1.1%, Cr≤0.01%, Ti≤0.001%, and the remainder being Al and unavoidable impurities; The preparation method of the AlMgSi optical mirror material includes the following steps: the AlMgSi alloy ingot is subjected to homogenization, extrusion molding, solution treatment and aging treatment in sequence to obtain the AlMgSi optical mirror material; the homogenization temperature is 480-520℃, and the extrusion molding temperature is 300-350℃.

2. The AlMgSi optical mirror material as described in claim 1, characterized in that, It includes the following components by weight percentage: Si: 0.5-0.6%, Fe: ≤0.05%, Cu: 0.18-0.27%, Mg: 0.9-1.0%, Cr≤0.01%, Ti≤0.001%, and the remainder being Al and unavoidable impurities.

3. A method for preparing the AlMgSi optical mirror material as described in claim 1 or 2, characterized in that, The process includes the following steps: the AlMgSi alloy ingot is subjected to homogenization, extrusion molding, solution treatment, and aging treatment in sequence to obtain AlMgSi optical mirror material; the homogenization temperature is 480-520℃, and the extrusion molding temperature is 300-350℃.

4. The preparation method according to claim 3, characterized in that, The heat equalization time is 6-10 hours. After heat equalization is completed, the mixture is cooled to room temperature.

5. The preparation method according to claim 4, characterized in that, The cooling method to room temperature is water cooling.

6. The preparation method according to claim 3, characterized in that, The extrusion ratio of the extrusion forming is 20-30.

7. The preparation method according to claim 3, characterized in that, The solution temperature is 490-510℃, and the solution time is 20-40 min.

8. The preparation method according to claim 3, characterized in that, The aging treatment is carried out at a temperature of 160-180℃ and a holding time of 4-8 hours.

9. The preparation method according to claim 3, characterized in that, The method for preparing the AlMgSi alloy ingot is as follows: the components are mixed and smelted at 730-750℃, a refining agent is added for refining, a protective gas is introduced during the smelting process, and after the smelting is completed, the mixture is allowed to stand, slag is removed, and the mixture is cast to obtain the AlMgSi alloy ingot.

10. The use of the AlMgSi optical mirror material as described in claim 1 or 2, characterized in that, The AlMgSi optical mirror material is used to fabricate mirrors.

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