High-conductivity and processability aluminum alloy profile and its processing method

Abstract

The application provides a high-conductivity and processing-performance aluminum alloy profile, which comprises the following components in percentage by mass: Si 0.35-0.4%, Fe 0.1-0.2%, Cu <=0.01%, Mn <=0.01%, Mg 0.4%-0.45%, Cr <=0.01%, Zn <=0.01%, Ti <=0.02%, Ni <=0.01%, Bi 0.01-0.05%, other elements <=0.03%, and the rest is Al, and the total of the above is 100%. The high-conductivity and processing-performance aluminum alloy profile and the processing method thereof are characterized in that the aluminum alloy profile is subjected to high-temperature overaging heat treatment process on the basis of 6 series aluminum alloy, still has certain strength, and although the performance is not as high as that of high-strength aluminum alloy such as 6061, the performance is much higher than that of 1 series aluminum alloy with low mechanical processing performance and low conductivity, can meet the part use and processing requirements of electric vehicles, and the aluminum alloy profile has high conductivity, and the conductivity is about 59%IACS, far higher than that of general aluminum alloy.

Description

Technical Field

[0001] This invention relates to a processing method for aluminum alloy tubes, and more particularly to an aluminum alloy profile with high electrical conductivity and processing performance, and its processing method. Background Technology

[0002] Pure aluminum has excellent electrical conductivity, but its machinability is low. Although its performance can be improved by cold deformation such as drawing, it is basically limited to wire. New energy vehicles and other applications require both high conductivity and certain machinability to facilitate processing into parts of various shapes, which existing aluminum alloy profiles cannot meet. Summary of the Invention

[0003] The purpose of this invention is to overcome and supplement the deficiencies in the existing technology, and to provide an aluminum alloy profile with high conductivity and machinability and its processing method. The aluminum alloy profile has the characteristics of high conductivity and certain machinability, which can meet the subsequent processing and system function requirements of its customers.

[0004] The technical solution adopted in this invention is:

[0005] A high-conductivity and high-processability aluminum alloy profile, comprising, by mass percentage: Si 0.35-0.4%, Fe 0.1-0.2%, Cu ≤0.01%, Mn ≤0.01%, Mg 0.4%-0.45%, Cr ≤0.01%, Zn ≤0.01%, Ti ≤0.02%, Ni ≤0.01%, Bi 0.01-0.05%, other elements ≤0.03%, with the remainder being Al, the total of which is 100%.

[0006] A method for processing aluminum alloy profiles with high electrical conductivity and machinability, comprising the following steps:

[0007] S1. By mass percentage, the aluminum alloy profiles comprise the following components: Al 98.25%–98.9%, Si 0.35–0.4%, Fe 0.1–0.2%, Cu ≤0.01%, Mn ≤0.01%, Mg 0.4%–0.45%, Cr ≤0.01%, Zn ≤0.01%, Ti ≤0.02%, Ni ≤0.01%, Bi 0.01–0.05%. Pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, chromium agent, and aluminum-titanium-boron grain refiner are weighed out according to the proportions of the above components, and then they are sequentially loaded into the melting furnace and heated to melt into an aluminum alloy molten liquid.

[0008] S2. Add aluminum-titanium-boron grain refiner to the aluminum alloy melt, and after degassing and filtration, cast the aluminum alloy melt into long aluminum alloy round casting rods.

[0009] S3. Homogenize the aluminum alloy round casting rod to obtain a long aluminum alloy round casting rod, and then cool it rapidly;

[0010] S4. Cut the homogenized long aluminum alloy round casting rod to obtain aluminum alloy short rods of equal length.

[0011] S5. After heating the aluminum alloy short bar, it is subjected to high-temperature extrusion, and online quenching is performed at the same time as the extrusion.

[0012] S6. The quenched aluminum alloy short bars are subjected to high-temperature over-aging treatment to obtain aluminum alloy profiles.

[0013] Preferably, in the processing method of the aluminum alloy profile with high conductivity and processing performance, the specific steps in step S1 are as follows:

[0014] S11. Pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, and chromium agent are sequentially loaded into a melting furnace, melted and held at a constant temperature to obtain a molten liquid.

[0015] S12. Add slag remover to the melt, remove slag, add alloy to adjust composition, and stir for 10-15 minutes. Then take a sample for spectral analysis to determine the chemical composition of each component within the range of step S1.

[0016] S13. Refine the melt for 40-60 minutes, then add a covering agent, keep it at the temperature and let it stand for 30-35 minutes, then pass argon gas to remove hydrogen, and finally filter to obtain aluminum alloy melt.

[0017] Preferably, in the processing method of the aluminum alloy profile with high conductivity and processing performance, the homogenization temperature in step S3 is 545℃-565℃, and the holding time is 5.5-6.5h.

[0018] Preferably, in the processing method of the aluminum alloy profile with high conductivity and processing performance, the high-temperature extrusion in step S5 specifically comprises:

[0019] S51. Prepare the mold, preheat the aluminum alloy short bar, mold cylinder and mold, and install the extrusion mold;

[0020] S52. The aluminum alloy short bar is extruded at high temperature in a mold, quenched online, straightened, and then cut to the required length to obtain aluminum alloy quenched extruded profile.

[0021] Preferably, the processing method for the high conductivity and machinability aluminum alloy profile includes the following: in step S51, the preheating temperature of the short aluminum alloy round casting rod is 490℃-520℃ for the head, and gradient preheating is adopted with a gradient of 3-6℃ / 100mm; the preheating temperature of the mold cylinder is 420℃-440℃; and the preheating temperature of the mold is 460℃-500℃.

[0022] Preferably, in the processing method of the aluminum alloy profile with high conductivity and processing performance, the high-temperature extrusion speed in step S52 is 8m / min-12m / min.

[0023] Preferably, in the processing method of the aluminum alloy profile with high conductivity and processing performance, the aging treatment temperature in step S6 is 295-305℃, and the holding time is 7-7.5h.

[0024] Advantages of this invention:

[0025] The present invention relates to a high conductivity and machinability aluminum alloy profile and its processing method. The aluminum alloy profile is based on 6-series aluminum alloy and undergoes a high-temperature over-aging heat treatment process, still possessing a certain strength. Although its performance is not as high as that of high-strength aluminum alloys such as 6061, it is much higher than that of 1-series aluminum alloys, which have high conductivity but low machinability. It can meet the requirements for the use and processing of parts in electric vehicles. Furthermore, the aluminum alloy profile has a high conductivity, approximately 59% IACS, far exceeding that of ordinary aluminum alloys. Detailed Implementation

[0026] The present invention will be further described below with reference to specific embodiments.

[0027] Example 1

[0028] A high-conductivity and high-processability aluminum alloy profile, comprising, by mass percentage: Si 0.36%, Fe 0.15%, Cu 0.01%, Mn 0.01%, Mg 0.4%, Cr 0.01%, Zn 0.01%, Ti 0.02%, Ni 0.01%, Bi 0.02%, other elements 0.03%, with the remainder being Al, the total of which is 100%.

[0029] The processing method of this embodiment includes the following steps:

[0030] S1. By mass percentage, the aluminum alloy profile includes the following components: Si 0.36%, Fe 0.15%, Cu 0.01%, Mn 0.01%, Mg 0.4%, Cr 0.01%, Zn 0.01%, Ti 0.02%, Ni 0.01%, Bi 0.02%, other elements 0.03%, and the remainder is Al, the total of which is 100%. Pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, chromium agent, and aluminum-titanium-boron grain refiner are weighed according to the proportion of the above components. Then, the pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, and chromium agent are sequentially charged into the melting furnace and heated to melt into aluminum alloy liquid.

[0031] The specific steps in step S1 are as follows:

[0032] S11. Pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, and chromium agent are then sequentially loaded into a melting furnace, melted and held at a temperature of 751℃, and stirred for 15 minutes to obtain a molten liquid.

[0033] S12. Add slag remover to the melt, stir again for 10 minutes to remove slag, add alloy to adjust composition, stir for 10 minutes, then take a sample for spectral analysis of chemical composition to ensure that each component is within the range of step S1;

[0034] S13. Refine the molten liquid for 50 minutes at a refining temperature of 770℃ to remove hydrogen and impurities from the solution. Then add a covering agent, keep it at the temperature and let it stand for 35 minutes. After that, argon gas is introduced to remove hydrogen, and finally filtered to obtain aluminum alloy molten liquid.

[0035] S2. The aluminum alloy melt is taken out of the furnace at 774℃, titanium boron wire is added online, and after online degassing and online filtration, it enters the vacuum casting system to start casting. The casting speed is 87mm / min, and the aluminum alloy melt is cast into long aluminum alloy round casting rods.

[0036] S3. Homogenize the aluminum alloy round casting rod to obtain a long aluminum alloy round casting rod, and then rapidly cool it. The homogenization temperature is 565℃ and the holding time is 5.5h.

[0037] S4. Cut the homogenized long aluminum alloy round casting rod to obtain aluminum alloy short rods of equal length.

[0038] S5. The aluminum alloy short bar is heated and then subjected to high-temperature extrusion, with online quenching occurring simultaneously with the extrusion. The high-temperature extrusion in step S5 specifically involves:

[0039] S51. Prepare the mold, preheat the aluminum alloy short bar, the die cylinder and the mold. The preheating temperature of the short aluminum alloy round casting bar is 515℃ at the head, and gradient preheating is adopted with a gradient of 3℃ / 100mm. The preheating temperature of the die cylinder is 420℃. The preheating temperature of the mold is 460℃. Install the extrusion mold.

[0040] S52. The aluminum alloy short bar is extruded at high temperature, quenched online, and straightened in the mold. The head of the short bar is preheated to 515℃ for extrusion. The extrusion speed is 9m / min. The bar is quenched online in a water tank and then straightened before being cut to the required length. The bar is then cut to the required length to obtain the aluminum alloy quenched extruded profile.

[0041] S6. The quenched profile is subjected to high-temperature over-aging treatment at a temperature of 296℃ and a holding time of 7h to obtain an aluminum alloy profile.

[0042] Example 2

[0043] A high-conductivity and high-processability aluminum alloy profile, comprising, by mass percentage: Si 0.4%, Fe 0.2%, Cu 0.01%, Mn 0.01%, Mg 0.45%, Cr 0.01%, Zn 0.01%, Ti 0.02%, Ni 0.01%, Bi 0.01%, other elements 0.03%, with the remainder being Al, totaling 100%.

[0044] A method for processing aluminum alloy profiles with high electrical conductivity and machinability, comprising the following steps:

[0045] S1. By mass percentage, the aluminum alloy profile comprises the following components: Si 0.4%, Fe 0.2%, Cu 0.01%, Mn 0.01%, Mg 0.45%, Cr 0.01%, Zn 0.01%, Ti 0.02%, Ni 0.01%, Bi 0.01%, other elements 0.03%, with the remainder being Al. Pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, chromium agent, and aluminum-titanium-boron grain refiner are weighed out according to the proportions of the above components, and then they are sequentially loaded into the melting furnace and heated to melt into an aluminum alloy molten liquid.

[0046] The specific steps in step S1 are as follows:

[0047] S11. Pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, and chromium agent are sequentially loaded into a melting furnace, melted and held at a temperature of 751℃, and stirred for 15 minutes to obtain a molten liquid.

[0048] S12. Add slag remover to the melt, remove slag, add alloy to adjust composition, stir for 10 minutes, then take a sample for spectral analysis of chemical composition to ensure that each component is within the range of step S1;

[0049] S13. Refine the melt for 50 minutes to remove hydrogen and impurities from the solution. Then add a covering agent, keep it at the temperature for 35 minutes, refine at 770℃, then pass argon to remove hydrogen, and finally filter to obtain aluminum alloy melt.

[0050] S2. The aluminum alloy melt is taken out of the furnace at 774℃. An aluminum-titanium-boron grain refiner is added to the aluminum alloy melt. After online degassing and online filtration, it enters the vacuum casting system to start casting. The casting speed is 87mm / min. The aluminum alloy melt is cast into long aluminum alloy round casting rods.

[0051] S3. Homogenize the aluminum alloy round casting rod to obtain a long aluminum alloy round casting rod, and then rapidly cool it. The homogenization temperature is 565℃ and the holding time is 6.5h.

[0052] S4. Cut the homogenized long aluminum alloy round casting rod to obtain aluminum alloy short rods of equal length.

[0053] S5. After heating the aluminum alloy short bar, it is subjected to high-temperature extrusion, and online quenching is performed at the same time as the extrusion.

[0054] The high-temperature extrusion in step S5 specifically involves:

[0055] S51. Prepare the mold, preheat the aluminum alloy short bar, die cylinder and mold, and install the extrusion mold. The preheating temperature of the short aluminum alloy round casting bar is 515℃ at the head, and gradient preheating is adopted with a gradient of 6℃ / 100mm; the preheating temperature of the die cylinder is 440℃; and the preheating temperature of the mold is 500℃.

[0056] S52. The aluminum alloy short bar is fed into the die for high-temperature extrusion, online quenching, and straightening. The high-temperature extrusion speed is 8m / min-12m / min. Then it is cut to the required length to obtain aluminum alloy quenched extruded profile.

[0057] S6. The quenched aluminum alloy short bars are subjected to high-temperature over-aging treatment at a temperature of 295℃ and a holding time of 7h to obtain aluminum alloy profiles.

[0058] The mechanical properties and electrical conductivity of the aluminum alloy profiles in Examples 1 and 2 were tested, and the experimental data are shown in Table 1.

[0059] Table 1

[0060] Comparison Projects Tensile strength / MPa Yield strength / MPa Conductivity / % IACS 6063-T6 aluminum alloy 225 193 51.1 6061-T6 aluminum alloy 294 271 39.4 1060-F aluminum alloy 75 34 57.3 Sample 1 of the present invention 130 78 59.5 Sample 2 of the present invention 127 77 59.7

[0061] As can be seen from Table 1, the aluminum alloy profiles of Examples 1-2 are based on 6-series aluminum alloys and have undergone high-temperature over-aging heat treatment, so they still have a certain strength. Although their performance is not as high as that of high-strength aluminum alloys such as 6061, their performance is much higher than that of 1-series aluminum alloys with high conductivity and low machinability, which can meet the requirements for the use and processing of parts in electric vehicles. The aluminum alloy profiles of Examples 1-2 have high conductivity, which is about 59% IACS, far exceeding that of ordinary aluminum alloys.

[0062] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for processing aluminum alloy profiles with high conductivity and machinability, characterized in that: Includes the following steps: S1. By mass percentage, the aluminum alloy profile comprises the following components: Al 98.25%~98.9%, Si 0.35-0.4%, Fe 0.1-0.2%, Cu≤0.01%, Mn≤0.01%, Mg 0.4%~0.45%, Cr≤0.01%, Zn≤0.01%, Ti≤0.02%, Ni≤0.01%, Bi0.01-0.05%. Pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, chromium agent, and aluminum-titanium-boron grain refiner are weighed according to the proportions of the above components, and then they are sequentially loaded into the melting furnace and heated to melt into aluminum alloy liquid. S2. Add aluminum-titanium-boron grain refiner to the aluminum alloy melt, and after degassing and filtration, cast the aluminum alloy melt into long aluminum alloy round casting rods. S3. Homogenize the aluminum alloy round casting rod to obtain a long aluminum alloy round casting rod, and then cool it rapidly; S4. Cut the homogenized long aluminum alloy round casting rod to obtain aluminum alloy short rods of equal length. S5. After heating the aluminum alloy short bar, it is subjected to high-temperature extrusion, and online quenching is performed at the same time as the extrusion. S6. The quenched aluminum alloy short bars are subjected to high-temperature over-aging treatment to obtain aluminum alloy profiles; The homogenization temperature in step S3 is 545 ℃-565 ℃, and the holding time is 5.5-6.5 h; the aging treatment temperature in step S6 is 295-305 ℃, and the holding time is 7-7.5 h.

2. The processing method for aluminum alloy profiles with high conductivity and processing performance as described in claim 1, characterized in that: The specific steps of step S1 are as follows: S11. Pure aluminum ingots, pure magnesium ingots, aluminum-silicon master alloy, manganese agent, and chromium agent are sequentially loaded into a melting furnace, melted and held at a constant temperature to obtain a molten liquid. S12. Add slag remover to the melt, remove slag, add alloy to adjust composition, and stir for 10 min-15 min. Then take a sample for spectral analysis of chemical composition to ensure that each component is within the range of step S1. S13. Refine the melt for 40 min-60 min, then add a covering agent, keep it at the temperature and let it stand for 30 min-35 min, then pass argon gas to remove hydrogen, and finally filter to obtain aluminum alloy melt.

3. The processing method for aluminum alloy profiles with high conductivity and machinability as described in claim 1, characterized in that: The high-temperature extrusion in step S5 is specifically as follows: S51. Prepare the mold, preheat the aluminum alloy short bar, mold cylinder and mold, and install the extrusion mold; S52. The aluminum alloy short bar is extruded at high temperature in a mold, quenched online, straightened, and then cut to the required length to obtain aluminum alloy quenched extruded profile.

4. The processing method for aluminum alloy profiles with high conductivity and machinability as described in claim 3, characterized in that: In step S51, the preheating temperature of the short aluminum alloy round casting rod is 490℃-520℃ for the head, using gradient preheating with a gradient of 3-6℃ / 100mm; the preheating temperature of the mold cylinder is 420℃-440℃; and the preheating temperature of the mold is 460℃-500℃.

5. The processing method for aluminum alloy profiles with high conductivity and machinability as described in claim 3, characterized in that: The high-temperature extrusion speed in step S52 is 8m / min-12m / min.