Aluminum alloy profile and preparation method thereof

Abstract

The invention discloses an aluminum alloy profile and a preparation method thereof. The aluminum alloy profile comprises the following components in percentage by mass: 0.35%-0.45% of Si, 0-0.10% of Fe, 0-0.05% of Cu, 0-0.05% of Mn, 0.50%-0.60% of Mg, 0-0.03% of Cr, 0-0.03% of Zn, 0-0.03% of Ti, less than 0.05% of a single impurity element, less than 0.15% in total, and the balance of Al. After the components and the component proportion of the aluminum alloy profile are optimized, the corrosion resistance of the aluminum alloy profile can be obviously improved, process parameters are controlled, the purpose of greatly reducing welding lines on the premise of meeting high performance is achieved, then the pressure of a mold is reduced, the service life of the mold is prolonged, and large-scale mass production is facilitated. In addition, by using the composite refining agent, the strength and corrosion resistance of the aluminum alloy profile are greatly improved, the aluminum alloy profile can adapt to more complex environments, and the machining performance of the aluminum alloy profile is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum alloy profiles, and in particular, to an aluminum alloy profile and a preparation method thereof. Background Art

[0002] When the aluminum profile is subjected to anodic oxidation surface treatment, the surface is finer, smoother and more corrosion-resistant than the substrate surface. However, the welding lines that are not visible on the substrate will appear after anodic oxidation. Generally, the welding lines are arranged at the corners through die design. However, for cross-sections such as round tubes and flat tubes, the welding lines cannot be arranged at the corners, and generally, it is solved by process design.

[0003] The conventional process design idea is to use means such as high temperature and low speed, increasing the extrusion ratio, and increasing the depth of the welding chamber to reduce the welding lines. This method has problems such as increasing the die pressure, reducing the die life, wasting more dies, being difficult to mass-produce, and taking a long time, thus affecting production.

[0004] In the prior art, the strength and corrosion resistance of aluminum alloy materials are also improved to make the aluminum alloy adapt to more environmental conditions, but there are also problems that the processing performance cannot be satisfied. Summary of the Invention

[0005] Based on this, in order to solve the problems that the strength, corrosion resistance and processing performance of aluminum alloy profiles in the prior art cannot meet the requirements, the present invention provides an aluminum alloy profile and a preparation method thereof. The specific technical solutions are as follows:

[0006] An aluminum alloy profile, the aluminum alloy profile comprises the following components in mass percentage: 0.35% - 0.45% Si, 0 - 0.10% Fe, 0 - 0.05% Cu, 0% - 0.05% Mn, 0.50% - 0.60% Mg, 0 - 0.03% Cr, 0 - 0.03% Zn, 0 - 0.03% Ti, the content of a single impurity element < 0.05%, the total content < 0.15%, and the balance is Al.

[0007] In addition, the present invention also provides a preparation method of an aluminum alloy profile. The preparation method comprises the following steps:

[0008] Weigh the materials according to the proportion of each element of the aluminum alloy profile, and obtain an ingot through melting treatment and semi-continuous hot-top casting;

[0009] Homogenize the ingot, then perform extrusion treatment, air-cooling quenching and aging treatment, and then perform oxidation treatment to obtain the aluminum alloy profile.

[0010] Further, the temperature of the smelting treatment is 720°C to 750°C to completely melt it. A covering agent is added to the melt, argon is introduced, and refining treatment is carried out. Each refining time is 20 min to 25 min. After each refining, it is left standing for 15 to 20 min and then the slag is skimmed off. The smelting process requires uniform composition, thorough degassing and slag removal. After the last standing and slag skimming, the melt is poured from the melting furnace into the holding furnace through a launder, and then an Al-5Ti-1B wire refiner is added by a double wire feeder for grain refinement, and online filtration is started.

[0011] Further, the covering agent is at least one of KCl, NaCl, and NaF;

[0012] Further, a composite refining agent is added in the refining treatment, and the addition amount of the composite refining agent accounts for 0.2% to 0.5% of the mass of the melt.

[0013] Further, the online filtration adopts double-stage filtration. The first-stage filtration adopts a 40-mesh ceramic foam filter plate, and the second-stage filtration adopts a 50-mesh ceramic foam filter plate.

[0014] Further, the temperature of the semi-continuous hot top casting is 720°C to 740°C, the speed is 75 mm / min to 85 mm / min, and the water pressure is 220 KPa to 230 KPa.

[0015] Further, the temperature of the homogenization treatment is 560°C, and it is held for 8 h.

[0016] Further, the extrusion treatment is carried out on a 25 MN forward extrusion press. The temperature of the ingot for extrusion on the machine is 510°C to 520°C, and the main cylinder speed is 3 mm / s.

[0017] Further, the temperature of the aging treatment is 200°C, and it is held for 1.5 h.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. After optimizing the composition and component ratio of the aluminum alloy profile, the present invention can significantly improve the corrosion resistance of the aluminum alloy profile, control the process parameters, greatly reduce the purpose of the bonding line on the premise of meeting high performance, thereby reducing the die pressure and prolonging the die life, which is beneficial to large-scale production.

[0020] 2. Before refining, a covering agent is added to the present invention for smelting, which can create a certain protective atmosphere, isolate the atmosphere, make it not easy to absorb hydrogen, promote the escape of hydrogen in the melt, and can effectively remove oxide inclusions. In cooperation with refining, by adding a composite refining agent, the α-Al grains become finer and the grain boundaries are more complexly interlaced, which can change the equilibrium state of the metal-gas system or the metal-inclusion system, so that gases and solid inclusions are completely separated from the melt, greatly increasing the strength and corrosion resistance of the aluminum alloy profile and enabling it to adapt to a more complex environment.

[0021] 3. The present invention strictly controls the contents of Si, Fe, and Mg to form a multi-phase with a certain proportion, significantly improving the microstructure and phase distribution of the aluminum alloy, significantly enhancing the mechanical properties, making the internal grain arrangement more regular and the comprehensive performance more excellent. Specific embodiments

[0022] In order to make the purpose, technical solutions and advantages of the present invention clearer, the following further details the present invention in conjunction with its embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the protection scope of the present invention.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0024] An aluminum alloy profile in an embodiment of the present invention includes the following components by mass percentage: 0.35% - 0.45% Si, 0 - 0.10% Fe, 0 - 0.05% Cu, 0 - 0.05% Mn, 0.50% - 0.60% Mg, 0 - 0.03% Cr, 0 - 0.03% Zn, 0 - 0.03% Ti, with a single impurity element <0.05% and a total <0.15%, and the balance is Al.

[0025] In addition, the present invention also provides a preparation method of an aluminum alloy profile, and the preparation method includes the following steps:

[0026] Weigh the materials according to the proportion of each element of the aluminum alloy profile, and obtain an ingot through smelting treatment and semi-continuous hot-top casting;

[0027] Homogenize the ingot, then perform extrusion treatment, solution treatment after air-cooling quenching, and then perform oxidation treatment to obtain the aluminum alloy profile.

[0028] In one embodiment, the temperature of the smelting treatment is 720°C to 750°C to completely melt it. A covering agent is added to the melt, argon is introduced, and refining treatment is carried out. Each refining time is 20 min to 25 min. After each refining, it is left standing for 15 to 20 min and then the slag is skimmed off. The smelting process requires uniform composition, thorough degassing and slag removal. After the last standing and slag skimming, the melt is poured from the melting furnace into the holding furnace through a launder, and then an Al-5Ti-1B wire refiner is added by a double wire feeder for grain refinement, and online filtration is started.

[0029] In one embodiment, the covering agent is at least one of KCl, NaCl, and NaF;

[0030] In one embodiment, a composite refining agent is added in the refining treatment, and the addition amount of the composite refining agent accounts for 0.2% to 0.5% of the mass of the melt.

[0031] In one embodiment, the composite refining agent is composed of CCl4, MgCl2, and C2Cl6 with a mass ratio of (1 to 3):(2 to 9):1.

[0032] In one embodiment, the online filtration adopts double-stage filtration. The first-stage filtration adopts a 40-mesh foam ceramic filter plate, and the second-stage filtration adopts a 50-mesh foam ceramic filter plate.

[0033] In one embodiment, the temperature of the semi-continuous hot top casting is 720°C to 740°C, the speed is 75 mm / min to 85 mm / min, and the water pressure is 220 KPa to 230 KPa.

[0034] In one embodiment, the temperature of the homogenization treatment is 560°C, and it is held for 8 h.

[0035] In one embodiment, the extrusion treatment is carried out on a 25 MN direct extrusion press. The temperature of the ingot for extrusion on the machine is 510°C to 520°C, and the main cylinder speed is 3 mm / s.

[0036] In one embodiment, the temperature of the aging treatment is 200°C, and it is held for 1.5 h.

[0037] The aluminum alloy profiles prepared by the above scheme have excellent strength and corrosion resistance, greatly reduce the purpose of the bonding wire on the premise of meeting high performance, thereby reducing the die pressure and prolonging the die life, which is beneficial to mass production.

[0038] The embodiments of the present invention will be described in detail below in conjunction with specific examples.

[0039] Example 1:

[0040] The aluminum alloy profile comprises the following components by mass percentage:

[0041] 0.35% Si, 0.01% Fe, 0.01% Cu, 0.02% Mn, 0.50% Mg, 0.02% Cr, 0.01% Zn, 0.01% Ti, with each individual impurity element < 0.05% and the total < 0.15%, and Al as the balance;

[0042] The preparation method of the aluminum alloy profile comprises the following steps:

[0043] Weigh the ingredients according to the proportion of each element of the aluminum alloy profile, melt and process them at a temperature of 750 °C until all are melted. Add a KCl covering agent to the melt, introduce argon gas, and add a composite refining agent (composed of CCl4, MgCl2, and C2Cl6 with a mass ratio of 3:5:1) for refining. Each refining time is 20 min. After each refining, let it stand for 20 min and then skim the slag. The melting process requires uniform composition, thorough degassing and slag removal. After the last standing and skimming of the slag, pour the melt from the melting furnace into the holding furnace through a launder. Then use a double wire feeder to add an Al-5Ti-1B wire refiner for grain refinement, turn on the online filtration, and the online filtration adopts double-stage filtration. The first stage of filtration uses a 40-mesh foam ceramic filter plate, and the second stage of filtration uses a 50-mesh foam ceramic filter plate; then at a temperature of 720 °C, at a speed of 75 mm / min and a water pressure of 220 KPa, perform semi-continuous hot top casting to obtain an ingot;

[0044] Keep the ingot at a temperature of 560 °C for 8 h, then perform extrusion processing, and the extrusion processing is carried out on a 25 MN direct extrusion press. The temperature of the ingot during extrusion on the machine is 510 °C, the main cylinder speed is 3 mm / s. After air-cooling quenching, perform aging treatment at a temperature of 200 °C for 1.5 h, and then perform oxidation treatment to obtain the aluminum alloy profile.

[0045] Example 2:

[0046] The aluminum alloy profile comprises the following components by mass percentage:

[0047] 0.45% Si, 0.01% Fe, 0.02% Cu, 0.03% Mn, 0.55% Mg, 0.02% Cr, 0.01% Zn, 0.02% Ti, with each individual impurity element < 0.05% and the total < 0.15%, and Al as the balance;

[0048] The preparation method of the aluminum alloy profile comprises the following steps:

[0049] Ingredients are proportioned according to the ratios of various elements in the aluminum alloy profile, and smelting treatment is carried out at a temperature of 750 °C until it is completely melted. A KCl covering agent is added to the melt, argon is introduced, and a composite refining agent (composed of CCl4, MgCl2, and C2Cl6 with a mass ratio of 2:7:1) is added for refining treatment. The refining time for each time is 20 min, and after each refining, it is left standing for 20 min and then the slag is skimmed off. The smelting process requires uniform composition, thorough degassing and slag removal. After the last standing and slag skimming, the melt is poured from the melting furnace into the holding furnace through a launder, and then an Al-5Ti-1B wire refiner is added using a double wire feeder for grain refinement. The on-line filtration is started, and the on-line filtration adopts double-stage filtration. The first stage of filtration uses a 40-mesh foam ceramic filter plate, and the second stage of filtration uses a 50-mesh foam ceramic filter plate; then at a temperature of 730 °C, at a speed of 80 mm / min and a water pressure of 230 KPa, semi-continuous hot top casting is carried out to obtain an ingot;

[0050] The ingot is held at a temperature of 560 °C for 8 h, and then extrusion treatment is carried out. The extrusion treatment is carried out on a 25 MN direct extrusion press. The temperature of the ingot during extrusion on the machine is 520 °C, the main cylinder speed is 3 mm / s, and after air-cooling quenching, aging treatment is carried out at a temperature of 200 °C for 1.5 h, and then oxidation treatment is carried out to obtain the aluminum alloy profile.

[0051] Example 3:

[0052] The aluminum alloy profile includes the following components by mass percentage:

[0053] 0.40% Si, 0.01% Fe, 0.03% Cu, 0.02% Mn, 0.60% Mg, 0.03% Cr, 0.02% Zn, 0.02% Ti, individual impurity elements < 0.05%, total < 0.15%, and the balance is Al;

[0054] The preparation method of the aluminum alloy profile includes the following steps:

[0055] Ingredients are proportioned according to the ratios of various elements in the aluminum alloy profile, and are melted through smelting treatment under the condition of a temperature of 720 °C to 750 °C until completely melted. A KCl covering agent is added to the melt, argon is introduced, and a composite refining agent (composed of CCl4, MgCl2, and C2Cl6 with a mass ratio of 1:8:1) is added for refining treatment. Each refining time is 25 minutes. After each refining, it is left standing for 20 minutes and then the slag is skimmed off. The smelting process requires uniform composition, thorough degassing and slag removal. After the last standing and slag skimming, the melt is poured from the melting furnace into the holding furnace through a launder, and then an Al-5Ti-1B wire grain refiner is added using a double wire feeder for grain refinement. Online filtration is started, and the online filtration adopts double-stage filtration. The first stage of filtration uses a 40-mesh foam ceramic filter plate, and the second stage of filtration uses a 50-mesh foam ceramic filter plate; then at a temperature of 740 °C, at a speed of 85 mm / min, and a water pressure of 230 KPa, semi-continuous hot top casting is carried out to obtain an ingot;

[0056] The ingot is held at a temperature of 560 °C for 8 hours, and then extrusion treatment is carried out. The extrusion treatment is carried out on a 25 MN direct extrusion press. The temperature of the ingot during extrusion on the machine is 520 °C, the main cylinder speed is 3 mm / s, and after air-cooling quenching, aging treatment is carried out at a temperature of 200 °C for 1.5 hours, and then oxidation treatment is carried out to obtain the aluminum alloy profile.

[0057] Comparative Example 1:

[0058] Compared with Example 3, the difference is that the aluminum alloy profile in Comparative Example 1 includes the following components by mass percentage, and the others are the same as in Example 3:

[0059] The aluminum alloy profile includes the following components by mass percentage:

[0060] 0.20% Si, 0.4% Fe, 0.03% Cu, 0.02% Mn, 0.20% Mg, 0.02% Zn, 0.02% Ti, single impurity element < 0.05%, total < 0.15%, and the balance is Al.

[0061] Comparative Example 2:

[0062] Compared with Example 3, the difference is that the temperature of the ingot during extrusion on the machine in Comparative Example 2 is 470 °C, and the others are the same as in Example 3.

[0063] Comparative Example 3:

[0064] Compared with Example 3, the difference is that the temperature of the ingot during extrusion on the machine in Comparative Example 3 is 480 °C, and the others are the same as in Example 3.

[0065] Comparative Example 4:

[0066] Compared with Example 3, the difference is that the temperature of the ingot for extrusion on the machine in Comparative Example 4 is 550 °C, and the others are the same as in Example 3.

[0067] Comparative Example 5:

[0068] Compared with Example 3, the difference is that the main cylinder speed in Comparative Example 5 is 5 mm / s, and the others are the same as in Example 3.

[0069] Comparative Example 6:

[0070] Compared with Example 3, the difference is that the refining agent in Comparative Example 6 is CCl4 with a single component, and the others are the same as in Example 3.

[0071] Comparative Example 7:

[0072] Compared with Example 3, the difference is that the refining agent in Comparative Example 7 is MgCl2 with a single component, and the others are the same as in Example 3.

[0073] Comparative Example 8:

[0074] Compared with Example 3, the difference is that the refining agent in Comparative Example 8 is C2Cl6 with a single component, and the others are the same as in Example 3.

[0075] The yield strength, tensile strength, elongation at break, intergranular corrosion depth, and exfoliation corrosion grade of the aluminum alloy profile samples of Examples 1 to 3 and the comparative samples of the aluminum alloy profiles of Comparative Examples 1 to 8 were tested, and the results are shown in Table 1 below.

[0076] Table 1: Performance test results

[0077]

[0078] It can be seen from the data analysis in Table 1 that by optimizing the composition and the component ratio and combining with the optimization of the process, the present invention can promote the obtaining of aluminum alloy profiles with more excellent mechanical properties and corrosion resistance, can increase their corrosion resistance in the subsequent oxidation process, and has more excellent processing performance.

[0079] In addition, in order to verify the influence in the oxidation process of the aluminum alloy profiles of the present invention, the aluminum alloy profile samples of Examples 1 to 3 and the comparative samples of the aluminum alloy profiles of Comparative Examples 1 to 8 were also subjected to oxidation treatment. The process of the oxidation treatment is: loading - water washing - alkali tank - degreasing - water washing - anodic oxidation - sealing - unloading. The specific process parameters are conventional techniques and will not be elaborated here. The results are shown in Table 2 below.

[0080] Table 2: Apparent results of aluminum alloy profiles

[0081]

[0082] From the data analysis in Table 2, it can be seen that through optimizing the composition, composition ratio and process parameters of the aluminum alloy profile, and combining with the optimization of the refining agent, the present invention can promote the comprehensive performance of the aluminum alloy profile, help to improve its corrosion resistance in the oxidation treatment process, greatly reduce the purpose of the bonding line on the premise of meeting high performance, and further reduce the die pressure, extend the die life, which is beneficial to large-scale production.

[0083] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0084] The above-described embodiments only represent several implementation manners of the present invention, and the description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. An aluminum alloy profile, characterized in that: The aluminum alloy profile includes the following components in mass percentage: 0.35% to 0.45% Si, 0 to 0.10% Fe, 0 to 0.05% Cu, 0 to 0.05% Mn, 0.50% to 0.60% Mg, 0 to 0.03% Cr, 0 to 0.03% Zn, 0 to 0.03% Ti, a single impurity element is less than 0.05%, a total of less than 0.15%, and Al is the balance.

2. A method for preparing an aluminum alloy profile, characterized in that: The preparation method is used to prepare the aluminum alloy profile according to claim 1, and the preparation method comprises the following steps: The aluminum alloy profile is prepared according to the proportion of each element, and an ingot is obtained through smelting treatment and semi-continuous hot top casting; The ingot is homogenized, extruded, air-cooled, quenched, aged, and oxidized to obtain an aluminum alloy profile.

3. The preparation method according to claim 2, characterized in that: The smelting treatment temperature is 720°C to 750°C to melt it completely, a covering agent is added to the melt, argon is introduced, and refining treatment is carried out. The refining time each time is 20min to 25min. After each refining, the slag is removed after standing for 15 to 20min. The smelting process requires uniform composition and thorough degassing and slag removal. After the last standing and slag removal, the melt is poured from the melting furnace into the holding furnace through the flow channel, and then a double wire feeder is used to add Al-5Ti-1B wire refiner for grain refinement, and online filtration is started.

4. The preparation method according to claim 2, characterized in that: The covering agent is at least one of KCl, NaCl and NaF.

5. The preparation method according to claim 2, characterized in that: A composite refining agent is added during the refining process, and the added amount of the composite refining agent accounts for 0.2% to 0.5% of the mass of the melt.

6. The preparation method according to claim 2, characterized in that: The online filtration adopts double-stage filtration, the first stage filtration adopts a 40-mesh foam ceramic filter plate, and the second stage filtration adopts a 50-mesh foam ceramic filter plate.

7. The preparation method according to claim 2, characterized in that: The temperature of the semi-continuous hot top casting is 720° C. to 740° C., the speed is 75 mm / min to 85 mm / min, and the water pressure is 220 KPa to 230 KPa.

8. The preparation method according to claim 2, characterized in that: The homogenization temperature is 560° C. and the temperature is kept for 8 hours.

9. The preparation method according to claim 2, characterized in that: The extrusion process is carried out on a 25MN forward extruder, the temperature of the ingot on the extruder is 510° C. to 520° C., and the main cylinder speed is 3 mm / s.

10. The preparation method according to claim 7, characterized in that: The aging treatment temperature is 200° C. and is kept at this temperature for 1.5 hours.

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