Recycled aluminum residual Sn modified 6000-series aluminum alloy profile and preparation method thereof

Abstract

The invention discloses a modified 6000-series aluminum alloy profile with recycled aluminum residual Sn and a preparation method of the modified 6000-series aluminum alloy profile, and belongs to the technical field of aluminum alloy preparation, and the preparation method comprises the following steps that S1, an aluminum alloy casting blank is smelted and cast; s2, the aluminum alloy casting blank is subjected to homogenization treatment; s3, the aluminum alloy casting blank is preheated; s4, the aluminum alloy casting blank in the step S3 is put into an extruding machine to be subjected to hot extrusion forming, so that an aluminum alloy profile is formed, and the temperature of an outlet of the extruding machine is larger than or equal to 525 DEG C; s5, the aluminum alloy profile in the step S4 is introduced into an ultrasonic water quenching tank to be subjected to ultrasonic water quenching treatment for 1-5 min; according to the method, the technical problem of recycling the tin-containing recycled aluminum is solved through the modification and ultrasonic quenching combined process of the recycled aluminum residual Sn, waste is turned into wealth, and the produced extruded profile is excellent in comprehensive performance and has remarkable economic and environment-friendly benefits.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of recycling aluminum residual Sn modified 6000 series aluminum alloy profile and its preparation method, belong to aluminum alloy preparation technical field. BACKGROUND

[0002] At present, 6000 series (Al-Mg-Si) aluminum alloy is the mainstream material of photovoltaic module frame due to its good comprehensive performance; With photovoltaic industry entering the scrap period, green recycling of a large number of retired components becomes an urgent need, however, the solder strip (Sn-Pb / Sn-Ag-Cu) in photovoltaic module and the tin-containing components in electronic and electrical waste aluminum will inevitably mix into recycled aluminum during recycling and crushing, resulting in excessive Sn impurity content in recycled aluminum; In traditional aluminum alloy metallurgy, Sn is usually regarded as harmful impurities. Because its melting point is low, the solid solubility in aluminum is small, and it is easy to segregate at grain boundary, which increases the thermal brittleness of alloy, deteriorates the extrusion formability and mechanical properties, especially seriously damages the corrosion resistance; Therefore, it is necessary to control the content and distribution characteristics of Sn in recycled aluminum, to realize the comprehensive optimization of mechanical properties, hot workability and corrosion resistance. The existing recycled aluminum is difficult to achieve the comprehensive performance comparable to new aluminum alloy due to the segregation of impurities such as Sn, which leads to increased grain boundary brittleness, grain coarsening and increased local corrosion sensitivity. In view of this problem, the present application proposes to use trace Sn (0.05-0.10 wt.%) as a modified component in recycled 6000 series aluminum alloy system, through precise formula design, homogenization, preheating, hot extrusion, and ultrasonic water quenching at the extrusion port and subsequent aging treatment, etc. Process, control the intragranular distribution and grain boundary behavior of Sn, make Sn distribute in a beneficial phase state, promote grain refinement and strengthening effect, and at the same time inhibit the increase of grain boundary brittleness and corrosion sensitivity, so as to realize the controllable modification of recycled aluminum residual Sn, and obtain recycled Sn modified 6000 series aluminum alloy profile with stable performance and controllable cost. SUMMARY

[0003] The technical problem to be solved by the present application is to overcome the defects of the prior art and provide a kind of recycling aluminum residual Sn modified 6000 series aluminum alloy profile and its preparation method. It can not only solve the technical problem of recycling and utilization of tin-containing recycled aluminum by recycling aluminum residual Sn modification and ultrasonic quenching combined process, but also produce extruded profiles with excellent comprehensive performance, which has significant economic and environmental benefits.

[0004] In order to solve the above technical problems, the technical scheme of the present application is as follows: a kind of recycling aluminum residual Sn modified 6000 series aluminum alloy profile preparation method, comprising the following steps: S1, alloy raw materials are prepared according to the following weight percentage of ingredients: Sn: 0.05-0.10 wt.%, Mg: 0.55-0.90 wt.%, Si: 0.65-1.00 wt.%, Cu: 0.02-0.10 wt.%, Fe≤0.35 wt.%, Mn≤0.10 wt.%, Cr≤0.10 wt.%, Zn≤0.08 wt.%, balance Al; melting and casting the alloy raw material into an aluminum alloy billet; S2, placing the aluminum alloy billet in step S1 into a homogenizing furnace, and homogenizing at 560℃±5℃ for 6-10h for homogenization treatment; S3, preheating the aluminum alloy billet in step S2, the heating temperature is 420-500℃, and the holding time is ≥3.5h; S4, placing the aluminum alloy billet in step S3 into an extruder for hot extrusion forming to form an aluminum alloy profile, and the outlet temperature of the extruder is ≥525℃; S5, introducing the aluminum alloy profile in step S4 into an ultrasonic water quenching tank for 1-5min of ultrasonic water quenching treatment; S6, placing the aluminum alloy profile in step S5 in an aging furnace for aging treatment to obtain a final recycled aluminum residual Sn modified 6000 series aluminum alloy profile; The temperature in the aging furnace is 175-190℃, and the holding time is ≤2h.

[0005] Further, the ultrasonic frequency range of the ultrasonic water quenching treatment in step S5 is 15-50KHz.

[0006] Further, the water flow rate in the ultrasonic water quenching tank is ≥3L / min·kg compared with the aluminum alloy profile.

[0007] Further, the ultrasonic water quenching tank is arranged at the outlet of the extruder, and a plurality of generators are uniformly arranged on the inner wall of the ultrasonic water quenching tank.

[0008] Further, the time for the aluminum alloy profile to completely enter the ultrasonic water quenching tank from the extruder is less than 15s.

[0009] The application also provides a recycled aluminum residual Sn modified 6000 series aluminum alloy profile prepared by the above preparation method; The chemical composition of the aluminum alloy profile is Sn: 0.05-0.10 wt.%, Mg: 0.55-0.90 wt.%, Si: 0.65-1.00 wt.%, Cu: 0.02-0.10 wt.%, Fe≤0.35 wt.%, Mn≤0.10 wt.%, Cr≤0.10 wt.%, Zn≤0.08 wt.%, balance Al.

[0010] Further, the Vickers hardness of the aluminum alloy profile is greater than or equal to 103 Hv, the tensile strength is greater than or equal to 309 MPa, the yield strength is greater than or equal to 297 MPa, and the elongation is greater than or equal to 9.5%.

[0011] By adopting the technical scheme, the present application has the following beneficial effects: In the present application, compared with the conventional 6000 series aluminum alloy composition, the residual Sn alloying scheme involved in the present application solves the technical problem of recycling of tin-containing waste aluminum, and turns waste into treasure. Compared with the ordinary heat treatment process of the aluminum alloy ingot, the heat treatment process of the present application greatly shortens the aging time of the alloy (from 190 DEG C / 4h to 190 DEG C / 2h), which achieves the purpose of energy saving and improving production efficiency. Compared with the ordinary heat treatment process of the aluminum alloy ingot, the heat treatment process of the present application greatly improves the aging hardness of the alloy while ensuring the intergranular corrosion resistance of the alloy (the hardness value is increased from 90 Hv to 104 Hv). BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 The table compares the hardness and strength of the aged aluminum alloy obtained from examples 1-6 and comparative examples 1-2 in the present application; Figure 2 The differential thermal analysis table in the present application determines that the overburning temperature of the 6000 series aluminum alloy ingot is 580 DEG C; Figure 3 The differential thermal analysis table in the present application determines that the aging temperature range of the 6000 series aluminum alloy is 175-190 DEG C; Figure 4 The 6000 series aluminum alloy backscattered scanning electron microscope morphology corresponding to example 1 and comparative example 1 in the present application; Figure 5 The hardness change curve corresponding to the 6000 series aluminum alloy aged at 190 DEG C corresponding to example 1 and comparative example 1 in the present application; Figure 6 The intergranular corrosion depth of the 6000 series aluminum alloy corresponding to example 1 and comparative example 1 in the present application; Figure 7 The alloy stress-strain curve corresponding to example 1, example 2 and comparative example 1 in the present application; Figure 8 The 6000 series aluminum alloy transmission electron microscope characterization of intracrystalline precipitated phase and grain boundary precipitate-free zone corresponding to example 1 and comparative example 1 in the present application. DETAILED DESCRIPTION

[0013] The present application provides a kind of recycling aluminum residual Sn modified 6000 series aluminum alloy profile and its preparation method, and those skilled in the art can learn from the content herein, and realize by improving process parameters appropriately.The particularly need to point out is that all similar substitutions and changes are obvious to those skilled in the art, and they all belong to the scope of the present application.The method and application of the present application have been described by preferred embodiments, and relevant personnel can obviously change or appropriately change and combine the method and application herein without departing from the content, spirit and scope of the present application, to realize and apply the present application technology.

[0014] In order to make the content of the present application more easily understood, the present application will be further described in detail below according to specific embodiments and in conjunction with the accompanying drawings.

[0015] Example one; As Figures 1-8 shown, a preparation method of a recycling aluminum residual Sn modified 6000 series aluminum alloy profile, comprising the following steps: S1, alloy raw materials are prepared according to the following weight percentage of components: Sn: 0.05-0.10 wt.%, Mg: 0.55-0.90 wt.%, Si: 0.65-1.00 wt.%, Cu: 0.02-0.10 wt.%, Fe≤0.35 wt.%, Mn≤0.10 wt.%, Cr≤0.10 wt.%, Zn≤0.08 wt.%, and the balance is Al; The above alloy raw materials are melted and cast into aluminum alloy billets; S2, the aluminum alloy billet in step S1 is placed in a homogenizing furnace for homogenization treatment at 560℃ for 8 h; S3, the aluminum alloy billet in step S2 is preheated, and the heating temperature is 480℃, and the holding time is 3.5h; S4, the aluminum alloy billet in step S3 is placed in an extruder for hot extrusion forming to form an aluminum alloy profile, and the outlet temperature of the extruder is 525℃; S5, the aluminum alloy profile in step S4 is introduced into an ultrasonic water quenching tank for 5min of ultrasonic water quenching treatment; S6, the aluminum alloy profile in step S5 is placed in an aging furnace for aging treatment to obtain the final recycling aluminum residual Sn modified 6000 series aluminum alloy profile; Specifically, the temperature in the aging furnace is 190℃, and the holding time is 2h.

[0016] Specifically, the ultrasonic frequency range of the ultrasonic water quenching treatment in step S5 is 15KHz.

[0017] In the embodiment, the ultrasonic wave can generate strong cavitation effect in water, effectively break the quenching steam insulation layer, realize rapid cooling, if the frequency is lower than 15KHz, the effect will be weakened, higher than 50KHz, the overall cooling efficiency will be decreased.

[0018] Specifically, the water flow rate in the ultrasonic water quenching tank is 3L / min·kg compared with the aluminum alloy profile.

[0019] Specifically, the ultrasonic water quenching tank is arranged at the outlet of the extruder, and a plurality of generators are uniformly arranged on the inner wall of the ultrasonic water quenching tank.

[0020] In the embodiment, the power density of the generator is 0.2~1.0 W / cm 2 , and the arrangement of the generator in the ultrasonic water quenching tank makes the aluminum alloy profile subjected to uniform ultrasonic field intensity during quenching.

[0021] Specifically, the time for the aluminum alloy profile to completely enter the ultrasonic water quenching tank from the extruder is less than 15s.

[0022] The application also provides a recycled aluminum residual Sn modified 6000 series aluminum alloy profile prepared by any one of the preparation methods. The composition of the aluminum alloy profile is Sn: 0.05~0.10 wt.%, Mg: 0.55~0.90 wt.%, Si: 0.65~1.00 wt.%, Cu: 0.02~0.10 wt.%, Fe≤0.35 wt.%, Mn≤0.10 wt.%, Cr≤0.10 wt.%, Zn≤0.08 wt.%, and the balance is Al.

[0023] Specifically, the Vickers hardness of the aluminum alloy profile is ≥103Hv, the tensile strength is ≥309 MPa, the yield strength is ≥297 MPa, and the elongation is ≥9.5%.

[0024] Example two; The basic steps of the embodiment are the same as those of example one, except that the Sn content in the alloy ingot in the embodiment is 0.06 wt.%.

[0025] Example three; The basic steps of the embodiment are the same as those of example one, except that the Mg content is adjusted to 0.85 wt.% and the Si content is adjusted to 1.0 wt.% in the embodiment.

[0026] Example four; The basic steps of the embodiment are the same as those of example one, except that the ultrasonic frequency range in step S5 in the embodiment is 50 KHz, and the ultrasonic time is 1 min.

[0027] Example 5; The basic steps of this embodiment are the same as those of Embodiment 1, except that the aging temperature in step S6 of this embodiment is 175 ℃.

[0028] Comparative Example 1; The basic steps of this comparative example are the same as those of Example 1, except that the alloy billet in this comparative example does not contain Sn alloying element.

[0029] Comparative Example 2; The basic steps of this comparative example are the same as those of Example 1, except that in this comparative example, after extrusion molding in step S4, ordinary water quenching treatment is performed.

[0030] The aluminum ingots obtained in Examples 1-5 and Comparative Examples 1-2 were all tested under the same conditions according to GB / T 228.1 "Tensive Testing of Metallic Materials" and GB / T7998-2023 "Evaluation Method for Intergranular Corrosion Susceptibility of Aluminum Alloys". The results of hardness, tensile strength, yield strength, and elongation were obtained. Figure 1 As shown; Depend on Figure 1 It can be seen that the hardness, tensile strength, yield strength and elongation of the 6000 series aluminum alloy obtained by the present invention are all higher than those of the comparative example. Figure 2 Differential thermal analysis characterization of the as-cast alloys corresponding to Example 1 and Comparative Example 1, by Figure 2 It can be seen that the addition of Sn has no significant effect on the homogenization temperature; Figure 3 Differential thermal analysis characterization of the extruded alloys for Example 1 and Comparative Example 1 was performed by... Figure 3 It can be seen that the addition of Sn has no significant effect on the aging temperature; Figure 4 Scanning electron microscopy characterization of the solid solution alloys of Example 1 and Comparative Example 1 was performed by... Figure 4 It can be seen that the addition of trace amounts of Sn did not produce the Mg2Sn phase, and it had a certain modifying effect on the morphology of the iron phase. Figure 5 The solid solution aging curves for Example 1, Comparative Example 1, and Comparative Example 2 are provided by... Figure 5 It can be seen that the addition of trace amounts of Sn can not only shorten the aging time, but also enhance the aging hardening effect; the addition of trace amounts of Sn combined with ultrasonic quenching composite process can further enhance the aging hardening effect while shortening the time. Figure 6 The stress-strain curves of the aged alloys corresponding to Examples 1, 2, and Comparative Example 1 are obtained from... Figure 6 It can be seen that the addition of trace amounts of Sn combined with the ultrasonic quenching process effectively improves the alloy strength while ensuring the alloy elongation. Figure 7 The intergranular corrosion morphologies corresponding to Example 1 and Comparative Example 1 are derived from...Figure 7 It can be seen that the addition of trace amounts of Sn combined with the ultrasonic quenching composite process ensures the alloy's resistance to intergranular corrosion. Figure 8 The intragranular and grain boundary precipitate morphologies of the alloys in Example 1 and Comparative Example 1 are shown in the transmission electron microscopy (TEM) images. Figure 8 It can be seen that the combined process of adding trace amounts of Sn and ultrasonic quenching ensures fine precipitation within the grains while narrowing the width of the precipitation zone at the grain boundaries; the above microstructure simultaneously ensures the alloy's strength and resistance to intergranular corrosion.

[0031] The Sn-modified 6000 series aluminum alloy profiles prepared by the above method exhibit Vickers hardness ≥103Hv, tensile strength ≥309 MPa, yield strength ≥297 MPa, and elongation ≥9.5%, with comprehensive mechanical properties reaching or even exceeding those of some native 6000 series aluminum alloys. More importantly, their intergranular corrosion depth is significantly reduced compared to the control samples without Sn or with ordinary quenching, demonstrating excellent corrosion resistance.

[0032] This profile is particularly suitable for structural components with strict requirements for strength, corrosion resistance and lightweight, such as photovoltaic module frames, building curtain wall support structures, new energy vehicle battery trays and body frames, high-end radiators, etc., opening up new market areas for the application of high-value recycled aluminum.

[0033] The specific embodiments described above further illustrate the technical problems, technical solutions, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing 6000 series aluminum alloy profiles modified with recycled aluminum residue Sn, characterized in that, Includes the following steps: S1. Alloy raw materials are prepared according to the following weight percentages: Sn: 0.05~0.10 wt.%, Mg: 0.55~0.90 wt.%, Si: 0.65~1.00 wt.%, Cu: 0.02~0.10wt.%, Fe≤0.35 wt.%, Mn≤0.10 wt.%, Cr≤0.10 wt.%, Zn≤0.08 wt.%, the balance is Al; The above alloy raw materials are melted and cast into aluminum alloy billets; S2. Place the aluminum alloy billet from step S1 into a homogenizing furnace and keep it at 560℃±5℃ for 6~10 h for homogenization treatment. S3. Preheat the aluminum alloy billet from step S2 to a temperature of 420-500℃ and hold it for ≥3.5h. S4. The aluminum alloy billet from step S3 is placed into an extrusion press for hot extrusion forming to form an aluminum alloy profile. The outlet temperature of the extrusion press is ≥525℃. S5. The aluminum alloy profile described in step S4 is introduced into an ultrasonic water quenching tank for ultrasonic water quenching treatment for 1 to 5 minutes. S6. Place the aluminum alloy profile from step S5 into an aging furnace for aging treatment to obtain the final recycled aluminum residue Sn-modified 6000 series aluminum alloy profile. The temperature inside the aging furnace is 175–190℃, and the holding time is ≤2h.

2. The method for preparing Sn-modified 6000 series aluminum alloy profiles based on recycled aluminum residues according to claim 1, characterized in that: The ultrasonic frequency range for the ultrasonic water quenching treatment in step S5 is 15–50 kHz.

3. The method for preparing Sn-modified 6000 series aluminum alloy profiles based on recycled aluminum residues according to claim 1, characterized in that: The ratio of water flow rate in the ultrasonic water quenching tank to that of the aluminum alloy profile is ≥3L / min·kg.

4. The method for preparing Sn-modified 6000 series aluminum alloy profiles based on recycled aluminum residues according to claim 1, characterized in that: The ultrasonic water quenching tank is located at the outlet of the extruder, and multiple generators are evenly installed on the inner wall of the ultrasonic water quenching tank.

5. The method for preparing Sn-modified 6000 series aluminum alloy profiles based on recycled aluminum residues according to claim 4, characterized in that: The time it takes for the aluminum alloy profile to completely enter the ultrasonic water quenching tank from the extruder is less than 15 seconds.

6. A Sn-modified 6000 series aluminum alloy profile obtained by any one of the preparation methods of claims 1 to 5, characterized in that: The composition of this aluminum alloy profile is Sn: 0.05~0.10 wt.%, Mg: 0.55~0.90 wt.%, Si: 0.65~1.00 wt.%, Cu: 0.02~0.10 wt.%, Fe≤0.35 wt.%, Mn≤0.10 wt.%, Cr≤0.10 wt.%, Zn≤0.08 wt.%, with the balance being Al.

7. A Sn-modified 6000 series aluminum alloy profile based on recycled aluminum residue as described in claim 6, characterized in that: The aluminum alloy profile has a Vickers hardness ≥103Hv, tensile strength ≥309 MPa, yield strength ≥297 MPa, and elongation ≥9.5%.

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