Conductive aluminum material processing method
Through simplified conductive aluminum processing methods, including melt casting, uniform heat treatment, medium-high and medium-low temperature rolling, and aging treatment, the problems of high energy consumption in the existing process and the inverse relationship between mechanical strength and conductivity are solved, and high-efficiency and low-energy-consuming conductive aluminum processing is achieved, which improves the conductivity and mechanical properties of the product.
Patent Information
- Application Number
- CN202510066747.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-16
- Publication Date
- 2025-04-18
AI Technical Summary
The existing conductive aluminum processing technology has problems such as high energy consumption, complex processes, and the mechanical strength and conductivity are inverse relationship, making it difficult to effectively balance the conductivity and mechanical properties.
A conductive aluminum processing method including melt casting, cutting head and tail, milling surface, uniform heat treatment, medium and high temperature rolling, rapid cooling, medium and low temperature rolling and aging treatment is adopted to simplify the process, only two hot rolling and one aging treatment are required, and solid solution quenching is required. By adjusting the precipitation phase type and dislocation density, conductivity and mechanical properties are improved.
Energy consumption saving and process simplification are achieved, and the conductivity and mechanical properties of conductive aluminum are improved, so that the yield strength is ≥150MPa, the tensile strength is ≥170MPa, and the conductivity is ≥60.0% IACS.
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Figure CN119843188A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of aluminum alloys, and in particular to a conductive aluminum material processing method. Background Art
[0002] Conductive aluminum has the advantages of light weight and low cost compared to conductive copper. Although its conductivity is only about 60% of that of copper, it is still the best choice to replace copper through reasonable design and utilization. Conductive aluminum alloy grades include 1xxx, 5xxx and 6xxx. Traditional conductive aluminum materials are aluminum wires, which are obtained through extrusion, drawing and other processing technologies. In recent years, conductive aluminum bars can be obtained by stamping, bending and other processing technologies using aluminum plates with excellent conductive properties, that is, rolled aluminum alloys have achieved new development in the field of conductivity.
[0003] 6xxx conductive aluminum alloy has good electrical conductivity and medium strength. The conventional production process is: melting → homogenization heat treatment → cutting head and tail → milling → hot rolling → cold rolling → quenching → aging. The highest electrical conductivity is generally 56.5-59.5% IACS, and the yield strength is generally 60-170MPa. In addition, the energy consumption is high and the process is complicated. Patent CN114606414B is a high-conductivity recycled aluminum alloy wire and its preparation method. Although the design has a high tolerance for Fe elements, the tolerance for Si and Mg is relatively low, and there are limitations on the input category of recycled aluminum. The process is homogenization treatment, hot rolling, solution treatment, cold rolling and aging treatment. The product has a tensile strength of 120-180MPa and a conductivity of 37.6-59.2% IACS. The invention has higher energy consumption and complex processes. In addition, both the conventional production process and the patented process have the disadvantage that mechanical strength and conductivity are inversely related.
[0004] Therefore, there is an urgent need to develop a conductive aluminum processing method that has high production efficiency, low energy consumption, and can balance electrical conductivity and mechanical properties. Summary of the invention
[0005] In view of the above shortcomings, the present invention provides a conductive aluminum material processing method, which can effectively save energy consumption, simplify the process, only require two hot rolling and one aging treatment, and no solution quenching is required. In addition, the process can effectively adjust the precipitation phase type and dislocation density, and effectively improve the conductivity and mechanical properties. The specific technical scheme is as follows:
[0006] A conductive aluminum material processing method comprises the following steps: melting and casting, head and tail cutting, milling, homogenization heat treatment, medium-high temperature rolling, rapid cooling, medium-low temperature rolling, and aging treatment. The ingot obtained by melting and casting the aluminum alloy raw material is subjected to head and tail cutting and surface milling, homogenization heat treatment, medium-high temperature rolling, rapid cooling, medium-low temperature rolling after cooling, and aging treatment directly after rolling to obtain the conductive aluminum material.
[0007] In the melting and casting step, the mass percentage of the chemical composition of the ingot is: Si: 0.1-0.7, Fe: 0.05-0.5, Cu: 0.05-0.2, Mg: 0.1-0.7, other single inevitable impurities ≤ 0.02, and the balance is Al.
[0008] Preferably, the temperature of the homogenization heat treatment process is 520-550°C and the time is 10-15h. The homogenization heat treatment temperature of the present invention is relatively high, the purpose is to make the precipitation of the Fe-containing phase of the recycled aluminum ingot more uniform, the needle-shaped Fe-containing phase is transformed into the shape of Chinese characters, and promote the dissolution of primary phase atoms such as β(Mg2Si), θ(Al2 Cu), and Q(Al5Cu2Mg8Si6).
[0009] Preferably, the medium-high temperature rolling process comprises: maintaining the metal temperature at 450-500° C. and rolling to a thickness of 20-40 mm, with a pass processing rate of 40-50%.
[0010] Preferably, the rapid cooling process comprises: rapid cooling by air cooling or water cooling, the metal cooling rate is greater than 20°C / min, and the metal is cooled to 200-250°C.
[0011] Preferably, the medium-low temperature rolling process comprises: maintaining the metal temperature at 160-210° C. and rolling to a thickness of 2-8 mm, with a pass processing rate of 45-55%.
[0012] Preferably, the temperature of the aging treatment process is 200-250°C, and the insulation time is 6-30h.
[0013] Preferably, the aluminum in the aluminum alloy raw material also includes recycled aluminum from the consumer end.
[0014] Compared with the prior art, the present invention has the following beneficial effects:
[0015] 1. A conductive aluminum material processing method of the present invention comprises the following steps: melting, cutting, milling, homogenization heat treatment, medium-high temperature rolling, rapid cooling, medium-low temperature rolling, and aging treatment. The present invention effectively saves energy consumption and simplifies the process. It only requires homogenization heat treatment, two hot rollings, and one aging treatment. It does not require solid solution quenching, and the process can effectively adjust the precipitation phase type and dislocation density. The purpose of uniform heating is to make the precipitation of Fe-containing phase in the recycled aluminum ingot more uniform, the needle-shaped Fe-containing phase is transformed into the shape of Chinese characters, and the primary phase atoms such as β (Mg2Si), θ (Al2 Cu), and Q (Al5Cu2Mg8Si6) are promoted to dissolve back; hot rolling at 450-500℃ in the medium and high temperature stage can break up the dispersed phase and the remaining primary phase at high temperature, and promote the continued dissolution of solute atoms; hot rolling at 160-250℃ in the medium and low temperature stage can obtain the target thickness alloy, and at the same time, the matrix undergoes lattice distortion and dynamic recovery, and precipitation phases such as Mg / Si are precipitated. After aging heat treatment at 200-250℃, the matrix continues to recover to generate a large number of subgrains, and precipitation phases such as Mg / Si grow and coarsen. At this time, the mechanical strength is compensated, and because the solute atoms in the matrix are reduced, the electron scattering effect is reduced, and the conductivity is improved. The final yield strength is ≥150MPa, the tensile strength is ≥170MPa, and the conductivity is ≥60.0%IACS.
[0016] 2. The present invention can use recycled aluminum from the consumer end as raw material, does not affect the mechanical properties of the product, increases the tolerance of recycled aluminum from the consumer end, and promotes the recycling of recycled aluminum in automobiles. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0018] Figure 1 It is a schematic diagram of the process flow of the present invention;
[0019] Figure 2 TEM image of the grain structure and precipitation phase of the plate of Example 1 of the present invention. DETAILED DESCRIPTION
[0020] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments. Unless otherwise defined, all professional terms used hereinafter have the same meaning as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the protection scope of the present invention. Unless otherwise specifically stated, various raw materials, reagents, instruments and equipment used in the present invention, etc. can be purchased from the market or can be prepared by existing methods.
[0021] As an example, the aluminum used in the embodiment of the present invention is recycled aluminum from the consumer end, but the present invention is not limited to this.
[0022] Example 1
[0023] A conductive aluminum material processing method of this embodiment includes the following steps: melting, cutting, milling, homogenizing heat treatment, medium-high temperature rolling, rapid cooling, medium-low temperature rolling, and aging treatment. The specific steps are:
[0024] Melting and casting: Put the raw materials into a melting furnace for melting and casting to obtain an ingot; the mass percentage of chemical elements of the ingot after melting and casting is: Si: 0.36, Fe: 0.22, Cu: 0.15, Mg: 0.47, other single inevitable impurities ≤ 0.02, and the balance is Al.
[0025] 2) Head and tail trimming and surface milling: the ingot is trimmed and surface milled to obtain a milled ingot.
[0026] 3) Homogenization heat treatment: The milled ingot is subjected to homogenization heat treatment at a temperature of 530° C. for 12 h to obtain a heat-treated ingot.
[0027] 4) Medium-high temperature rolling: The heat-treated ingot is subjected to medium-high temperature rolling, the metal temperature is maintained at 480°C and the rolling is performed to a thickness of 20 mm, the pass processing rate is 45%, and the medium-high temperature rolled aluminum material is obtained.
[0028] 5) Rapid cooling: The aluminum material rolled at medium and high temperatures is rapidly cooled by air cooling or water cooling. The cooling rate of the aluminum material is 25°C / min, and the aluminum material is cooled to 220°C.
[0029] 6) Medium-low temperature rolling: The rapidly cooled aluminum material is subjected to medium-low temperature rolling, and the metal temperature is maintained at 180°C and rolled to a thickness of 7 mm, with a pass processing rate of 48%, to obtain aluminum material that has been rolled at medium-low temperature.
[0030] 7) Aging treatment: The aluminum material rolled at medium and low temperature is directly subjected to aging treatment at a temperature of 220° C. for 18 hours. After the aging treatment, the aluminum material of the present invention is obtained.
[0031] Example 2
[0032] A conductive aluminum material processing method of this embodiment includes the following steps: melting, cutting, milling, homogenizing heat treatment, medium-high temperature rolling, rapid cooling, medium-low temperature rolling, solution quenching, and aging treatment. The specific steps are:
[0033] 1) Melting and casting: Put the raw materials into a melting furnace and melt them to obtain an ingot; the mass percentage of the chemical elements of the ingot after melting and casting is: Si: 0.63, Fe: 0.10, Cu: 0.13, Mg: 0.18, other single inevitable impurities are ≤0.02, and the balance is Al.
[0034] 2) Head and tail trimming and surface milling: the ingot is trimmed and surface milled to obtain a milled ingot.
[0035] 3) Homogenization heat treatment: The milled ingot is subjected to homogenization heat treatment at a temperature of 520° C. for 15 h to obtain a heat-treated ingot.
[0036] 4) Medium-high temperature rolling: The heat-treated ingot is subjected to medium-high temperature rolling, the metal temperature is maintained at 450°C and the rolling is performed to a thickness of 28 mm, the pass processing rate is 45%, and the medium-high temperature rolled aluminum material is obtained.
[0037] 5) Rapid cooling: The aluminum material rolled at medium and high temperature is rapidly cooled by air cooling or water cooling. The cooling rate of the aluminum material is 25℃ / min, and the aluminum material is cooled to 200℃.
[0038] 6) Medium-low temperature rolling: The rapidly cooled aluminum material is subjected to medium-low temperature rolling, and the metal temperature is maintained at 160° C. and rolled to a thickness of 8 mm, with a pass processing rate of 49%, to obtain a medium-low temperature rolled aluminum material.
[0039] 7) Aging treatment: The aluminum material rolled at medium and low temperature is directly subjected to aging treatment at a temperature of 200° C. for a holding time of 30 hours. After the aging treatment, the aluminum material of the present invention is obtained.
[0040] Example 3
[0041] A conductive aluminum material processing method of this embodiment includes the following steps: melting, cutting, milling, homogenizing heat treatment, medium-high temperature rolling, rapid cooling, medium-low temperature rolling, and aging treatment. The specific steps are:
[0042] 1) Melting and casting: Put the raw materials into a melting furnace and melt them to obtain an ingot; the mass percentage of the chemical elements of the ingot after melting and casting is: Si: 0.20, Fe: 0.39, Cu: 0.18, Mg: 0.52, other single inevitable impurities are ≤0.02, and the balance is Al.
[0043] 2) Head and tail trimming and surface milling: the ingot is trimmed and surface milled to obtain a milled ingot.
[0044] 3) Homogenization heat treatment: The milled ingot is subjected to homogenization heat treatment at a temperature of 550° C. for 10 h to obtain a heat-treated ingot.
[0045] 4) Medium-high temperature rolling: The heat-treated ingot is subjected to medium-high temperature rolling, the metal temperature is maintained at 500°C and the rolling is performed to a thickness of 25 mm, the pass processing rate is 45%, and the medium-high temperature rolled aluminum material is obtained.
[0046] 5) Rapid cooling: The aluminum rolled at medium and high temperatures is rapidly cooled by air cooling or water cooling. The cooling rate of the aluminum is 22°C / min, and the aluminum is cooled to 250°C.
[0047] 6) Medium-low temperature rolling: The rapidly cooled aluminum material is subjected to medium-low temperature rolling, and the metal temperature is maintained at 210° C. and rolled to a thickness of 8 mm, with a pass processing rate of 50%, to obtain the aluminum material that has been rolled at medium-low temperature.
[0048] 7) Aging treatment: The aluminum material rolled at medium and low temperature is directly subjected to aging treatment at a temperature of 250° C. for a holding time of 6 hours. After the aging treatment, the aluminum material of the present invention is obtained.
[0049] Comparative Example 1
[0050] The difference between this comparative example and Example 1 is that the medium-low temperature rolling is replaced by cold rolling, the final cold rolling temperature is 70° C., and the other processes are the same as those in Example 1.
[0051] Comparative Example 2
[0052] The difference between this comparative example and Example 1 is that the medium-low temperature rolling is replaced by 520-530°C hot rolling, the hot rolling final rolling temperature is 310°C, and the other processes are the same as Example 1.
[0053] Comparative Example 3
[0054] The rolling process of this comparative example is: the heat-treated ingot is subjected to medium-high temperature rolling, the metal temperature is maintained at 480°C, the ingot is rolled to a thickness of 18 mm, the pass processing rate is 45%, and then the ingot is solid-solutionized at 500°C for 8 hours, and then cold-rolled, the cold-rolling pass processing rate is 48%. The remaining processes are the same as those in Example 1.
[0055] Comparative Example 4
[0056] This comparative example is a conventional production process, including: melting and casting, cutting head and tail, milling, homogenization heat treatment, hot rolling, cold rolling, solution quenching, aging treatment, the specific steps are:
[0057] 1) Melting and casting: Put the raw materials into a melting furnace and melt them to obtain an ingot; the mass percentage of the chemical elements of the ingot after melting and casting is: Si: 0.45, Fe: 0.10, Cu: 0.05, Mg: 0.40, other single inevitable impurities are all <0.02, and the balance is Al.
[0058] 2) Head and tail trimming and surface milling: the ingot is trimmed and surface milled to obtain a milled ingot.
[0059] 3) Homogenization heat treatment: The milled ingot is subjected to homogenization heat treatment at a temperature of 560° C. for 10 h to obtain a heat-treated ingot, which is then naturally cooled to room temperature.
[0060] 4) Hot rolling: The ingot is hot rolled at a starting rolling temperature of 540° C., rolled to a thickness of 8 mm, a final rolling temperature of 310° C., a pass processing rate of 40%, and then naturally cooled to room temperature.
[0061] 5) Cold rolling: The hot rolled billet is cold rolled to 3 mm, the final cold rolling temperature is 70°C, and then naturally cooled to room temperature.
[0062] 6) Solution quenching: The cold rolled coil is solution quenched at a solution temperature of 520°C, a holding time of 10 min, and a quenching cooling rate of 8°C / s.
[0063] 7) Aging treatment: The quenched coil is directly subjected to aging treatment at a temperature of 200°C and a holding time of 25h.
[0064] 1.TEM test
[0065] The grain structure and precipitation phase characteristics of the alloy product of Example 1 were observed and characterized using a FEI Talos F200X transmission electron microscope. The TEM image is at
[001] Al The sample was taken on the crystal axis. The TEM observation sample was first mechanically ground and then further thinned and perforated using a DJ-2000 electrolytic double spray instrument. The electrolyte was 25% HNO3 methanol solution, the working voltage was 15-25V, the working current was 40-55mA, and the temperature was about -35℃. The results are as follows Figure 2 shown.
[0066] 2. Conductivity and mechanical properties test
[0067] The aluminum alloy plates in Examples 1-3 and Comparative Examples 1-5 were subjected to performance tests according to ASTM standards, and the test results are shown in Table 1 below:
[0068] Table 1 Various properties of aluminum materials obtained in various embodiments and comparative examples
[0069]
[0070] In summary, the present invention provides a conductive aluminum material processing method, comprising the following steps: melting, cutting, milling, homogenizing heat treatment, medium-high temperature rolling, rapid cooling, medium-low temperature rolling, and aging treatment, which effectively saves energy consumption and simplifies the process. Only two hot rollings and one aging treatment are required, and no solid solution quenching is required. In addition, the process can effectively adjust the precipitation phase type and dislocation density. The hot rolling in the medium-high temperature stage can crush the dispersed phase and the remaining primary phase at high temperature, and promote the solute atoms to continue to dissolve back. The hot rolling in the medium-low temperature stage can obtain the target thickness alloy. At the same time, the matrix undergoes lattice distortion and dynamic recovery, and precipitation phases such as Mg / Si are precipitated. After aging heat treatment, the matrix continues to recover to generate a large number of subgrains, and the precipitation phases such as Mg / Si grow and coarsen. At this time, the mechanical strength is compensated, and because the solute atoms in the matrix are reduced, the electron scattering effect is reduced, and the conductivity is improved, so that the product yield strength is ≥150MPa, the tensile strength is ≥170MPa, and the conductivity is ≥60.0%IACS. The embodiment of the present invention uses recycled aluminum from the consumer end as raw material, which does not affect the electrical conductivity and mechanical properties of the product, improves the tolerance of recycled aluminum from the consumer end, and promotes the recycling of recycled aluminum.
[0071] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.
Claims
1. A conductive aluminum material processing method, characterized in that: The process comprises the following steps: melting and casting, cutting heads and tails, milling, homogenizing heat treatment, medium-high temperature rolling, rapid cooling, medium-low temperature rolling, and aging treatment. The ingot obtained by melting and casting the aluminum alloy raw material is cut heads and tails, milled, homogenized heat treated, and then medium-high temperature rolling is performed, and then rapidly cooled, and then medium-low temperature rolling is performed after cooling. After the rolling is completed, aging treatment is directly performed to obtain the conductive aluminum material. In the melting and casting step, the chemical composition of the ingot is in the following mass percentages: Si: 0.1-0.7%, Fe: 0.05-0.5%, Cu: 0.05-0.2%, Mg: 0.1-0.7%, inevitable impurities ≤ 0.02%, and the balance is Al.
2. A conductive aluminum material processing method according to claim 1, characterized in that: The temperature of the homogenization heat treatment process is 520-550° C. and the time is 10-15 hours.
3. A conductive aluminum material processing method according to claim 1, characterized in that: The medium-high temperature rolling process includes: maintaining the metal temperature at 450-500° C. and rolling to a thickness of 20-40 mm, with a pass processing rate of 40-50%.
4. A conductive aluminum material processing method according to claim 1, characterized in that: The rapid cooling process includes: rapid cooling by air cooling or water cooling, the metal cooling rate is greater than 20°C / min, and the metal is cooled to 200-250°C.
5. A conductive aluminum material processing method according to claim 1, characterized in that: The medium-low temperature rolling process includes: maintaining the metal temperature at 160-210° C. and rolling to a thickness of 2-8 mm, with a pass processing rate of 45-55%.
6. A conductive aluminum material processing method according to claim 1, characterized in that: The temperature of the aging treatment process is 200-250° C., and the insulation time is 6-30 hours.
7. A conductive aluminum material processing method according to claim 1, characterized in that: The aluminum in the aluminum alloy raw material also includes recycled aluminum from the consumer end.
8. An aluminum material prepared by the conductive aluminum material processing method according to any one of claims 1 to 7.