Aluminum alloy and processing method thereof

Abstract

The invention discloses an aluminum alloy and a processing method thereof, according to the processing method of the aluminum alloy, the aluminum alloy with refined grains and improved gloss is finally processed by optimizing the content of each element in the raw materials of the aluminum alloy and carrying out homogenization treatment and extrusion forming on the alloy, and the aluminum alloy is suitable for production of high-end electronic structural parts.

Description

Technical Field

[0001] This invention belongs to the field of aluminum alloy processing technology, specifically relating to an aluminum alloy and a processing method for the aluminum alloy. Background Technology

[0002] Grain refinement not only determines the strength and toughness of a material but also directly affects its surface appearance, gloss, and subsequent processing stability. Currently, 6-series aluminum alloys (Mg: 0.8%-1.2%, Si: 0.4%-0.8%, Cu: 0.15%-0.4%, Mn: 0-0.15%, Cr: 0.04%-0.35%, Fe: 0-0.7%, Zn: <0.25%, Ti: <0.15%), while possessing good overall performance, exhibit defects in actual production such as coarse grains, uneven microstructure, and concentrated stress during hot working. These defects are particularly pronounced during extrusion and post-processing, resulting in poor gloss, poor deformability, and susceptibility to cracking. Existing technologies primarily optimize from a post-processing perspective, with limited effectiveness, lacking a systematic control approach encompassing the entire process from source to composition to manufacturing process. Summary of the Invention

[0003] The primary objective of this invention is to provide an aluminum alloy processing method that addresses the shortcomings of existing technologies, such as coarse grains and poor gloss in aluminum alloys.

[0004] A second objective of this invention is to provide an aluminum alloy.

[0005] To achieve the above objectives, the following technical solution is adopted: A method for processing aluminum alloys includes the following steps: S1. Homogenization of aluminum alloy: The raw aluminum alloy is melted and cast into aluminum ingots. The aluminum ingots are heated and held at the temperature, and then rapidly cooled to room temperature, with the cooling rate controlled at 500-750℃ / h. The raw material aluminum alloy comprises the following components by weight percentage: Mg 0.85%-1.15%, Si 0.45%-0.75%, Cu 0.10%-0.40%, Fe <0.20%, Mn <0.1%, Zn <0.10%, Cr <0.03%, Ti <0.02%, other individual elements <0.03%, total other element components <0.15%, and the balance is Al; S2. Extrusion molding: The homogenized ingot is subjected to isothermal extrusion molding, with the extrusion temperature controlled at 500±20℃ and the outlet temperature controlled at 510-560℃. After discharge, the ingot is cooled to obtain the finished aluminum alloy.

[0006] In this invention, in step S1, the aluminum ingot is heated to 575°C at a rate of 190°C / h and held at that temperature for 5-8 hours.

[0007] In this invention, the rapid cooling in S1 includes first air cooling, followed by rapid liquid cooling. Rapid liquid cooling suppresses the precipitation of coarse Mg2Si phase, while air cooling releases thermal stress and prevents subsequent overcooling deformation.

[0008] Furthermore, the air cooling involves cooling in a cooling furnace for 5-10 minutes.

[0009] Furthermore, the rapid liquid cooling process involves cooling to room temperature at a rate of 500-750℃ / h.

[0010] In this invention, the aluminum alloy homogenization process is carried out in a homogenizing furnace. The aluminum ingots are stacked in layers within the furnace, with high-temperature resistant spacers separating the layers at intervals of 30-90 mm. This arrangement ensures uniformity in heating and cooling.

[0011] In this invention, the die used in the extrusion process of S2 has a flow-restricting angle, which is 3°-12°. During the extrusion process, the aluminum alloy cast rod is pushed towards the die by the extruder to be formed. The design of the die with the flow-restricting angle promotes grain refinement. After passing through the flow-restricting angle, the grains are continuously broken down. That is, the high strain and high strain rate introduced by the flow-restricting angle induce continuous dynamic recrystallization, forming very fine equiaxed grains in the area near the working zone, which helps to improve the strength, toughness and surface quality of the profile in this area.

[0012] In this invention, the cooling after discharge in S2 is achieved by online quenching.

[0013] An aluminum alloy is obtained by the above processing method.

[0014] The present invention has the following beneficial effects: (1) The aluminum alloy processing method of the present invention optimizes the content of each element in the aluminum alloy raw material, homogenizes the alloy and extrudes it, and finally obtains an aluminum alloy with refined grains and improved luster.

[0015] (2) The processing method of the present invention optimizes the die flow angle during extrusion and forms a uniform, fine grain structure through dynamic recrystallization by precise temperature control. Through comparative experiments, the present invention can effectively improve the grain refinement level and surface properties of alloys, and is suitable for the production of high-end electronic structural components. Attached Figure Description

[0016] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0017] Figure 1 These are physical images of ordinary coarse-grained 6-series materials and the high-brightness fine-grained material prepared by this invention; Figure 2Metallographic images of ordinary coarse-grained 6-series materials and high-brightness fine-grained materials prepared by this invention; Figure 3 This is a schematic diagram of the mold flow obstruction angle. Detailed Implementation

[0018] This invention proposes an aluminum alloy processing method that synergistically controls the composition of aluminum alloy raw materials and the hot working process. Specifically, it optimizes the Cr and Ti content in the aluminum alloy raw materials to improve nucleation ability, reduces Fe to prevent impurity coarsening, optimizes the die flow angle and flow ratio during extrusion, and achieves uniform, fine-grained structure through precise temperature control and dynamic recrystallization. This method enables the aluminum alloy to achieve uniform microstructure, fine grains, and improved gloss. The resulting aluminum alloy is suitable for the production of high-requirement 3C consumer electronics profiles and structural components. Details are as follows: A method for processing aluminum alloys includes the following steps: S1. Homogenization of aluminum alloy: The raw aluminum alloy is melted and cast into aluminum ingots. The aluminum ingots are heated and held at the temperature, and then rapidly cooled to room temperature, with the cooling rate controlled at 500-750℃ / h. The raw aluminum alloy comprises the following components by weight percentage: Mg 0.85%-1.15%, Si 0.45%-0.75%, Cu 0.10%-0.40%, Fe <0.20%, Mn <0.1%, Zn <0.10%, Cr <0.03%, Ti <0.02%, other individual elements <0.03%, total other element components <0.15%, with the balance being Al. The aluminum ingot is heated to 575℃ at a rate of 190℃ / h and held at that temperature for 5-8 hours.

[0019] Rapid cooling involves first air cooling, followed by rapid liquid cooling. Air cooling involves cooling in a cooling furnace for 5-10 minutes; liquid cooling involves cooling to room temperature at a rate of 500-750℃ / h.

[0020] S2. Extrusion molding: The homogenized ingot is subjected to isothermal extrusion molding, with the extrusion temperature controlled at 500±20℃ and the outlet temperature controlled at 510-560℃. After discharge, the ingot is cooled to obtain the finished aluminum alloy.

[0021] Table 1 shows the specific process parameters for the processing of Examples 1-4 and Comparative Examples 1-6 of the present invention. The grain size, gloss, coarse grain layer, and yield strength of the prepared aluminum alloys were tested, and the results are shown in Table 1. Physical images and metallographic images of the prepared high-gloss fine-grained materials are also provided. Figure 1 b and Figure 2 b.

[0022] Table 1. Properties of aluminum alloys obtained using different process parameters in the examples and comparative examples. As can be seen from Table 1 and the figure, the aluminum alloy prepared by this invention has the following advantages compared with traditional 6-series aluminum alloys: fine and uniform grains, improving surface quality; reasonable cooling design to avoid low-melting-point phase aggregation; stable extrusion and good tear resistance; suitable for industrial scale and has promotional value.

[0023] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for processing aluminum alloys, characterized in that, Includes the following steps: S1. Homogenization of aluminum alloy: The raw aluminum alloy is melted and cast into aluminum ingots. The aluminum ingots are heated and held at the temperature, and then rapidly cooled to room temperature, with the cooling rate controlled at 500-750℃ / h. The raw material aluminum alloy comprises the following components by weight percentage: Mg 0.85%-1.15%, Si 0.45%-0.75%, Cu 0.10%-0.40%, Fe <0.20%, Mn <0.1%, Zn <0.10%, Cr <0.03%, Ti <0.02%, other individual elements <0.03%, total other element components <0.15%, and the balance is Al; S2. Extrusion molding: The homogenized ingot is subjected to isothermal extrusion molding, with the extrusion temperature controlled at 500±20℃ and the outlet temperature controlled at 510-560℃. After discharge, the ingot is cooled to obtain the finished aluminum alloy.

2. The aluminum alloy processing method according to claim 1, characterized in that, In S1, the aluminum ingot is heated to 575℃ at a rate of 190℃ / h and held at that temperature for 5-8 hours.

3. The aluminum alloy processing method according to claim 2, characterized in that, The rapid cooling in S1 involves first air cooling, followed by rapid liquid cooling.

4. The aluminum alloy processing method according to claim 3, characterized in that, The air cooling process involves cooling in a cooling furnace for 5-10 minutes; the liquid cooling process involves cooling to room temperature at a rate of 500-750℃ / h.

5. The aluminum alloy processing method according to claim 3, characterized in that, The aluminum alloy homogenization process is carried out in a homogenizing furnace, in which the aluminum ingots are stacked in layers, with high-temperature resistant spacers separating the layers at intervals of 30-90 mm.

6. The aluminum alloy processing method according to claim 1, characterized in that, The die used in the extrusion process of S2 has a flow-blocking angle, which is 3°-12°.

7. The aluminum alloy processing method according to claim 6, characterized in that, In S2, online quenching is used for cooling after material discharge.

8. An aluminum alloy, characterized in that, Obtained by the method described in any one of claims 1-7.

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