Composite fin aluminum foil with high sagging resistance and processing technology thereof

Abstract

The invention discloses a composite fin aluminum foil with high sag resistance and a processing technology of the composite fin aluminum foil, and relates to the field of composite fin aluminum foils. According to the composite fin aluminum foil with high sag resistance and the processing technology of the composite fin aluminum foil with high sag resistance, the crystallization starting temperature of the composite fin aluminum foil can be reduced by increasing the cold rolling reduction; the temperature interval of the accelerated sagging stage is narrowed, and the sagging amount of the accelerated sagging stage is reduced, so that the sagging resistance of the material is improved, and the situation that the heat exchanger is scrapped due to the fact that collapse is likely to occur in a severe environment with constant pressure for about 10 min is effectively avoided; the anti-sagging performance of the composite fin aluminum foil can be remarkably improved by adopting finished product annealing, the sagging value of the composite fin aluminum foil is reduced along with the rise of the finished product annealing temperature, and the anti-sagging performance is improved. And after the finished product is annealed at 500 DEG C for 3 hours, the sagging resistance of the composite fin aluminum foil is the best.

Description

Technical Field

[0001] The invention relates to the technical field of composite fin aluminum foil, and in particular to a composite fin aluminum foil with high anti-droop performance and a processing technology thereof. Background Art

[0002] Composite fin aluminum foil (4343 aluminum-silicon alloy / core aluminum alloy / 4343 aluminum-silicon alloy, sandwich structure) is widely used in the field of automotive heat exchangers. It is characterized by light weight, good corrosion resistance, good thermal conductivity, etc. The anti-sagging performance of brazing aluminum foil refers to its ability to resist the natural sagging of gravity during the brazing process. It is an important indicator to measure the comprehensive performance of brazing aluminum foil. It can effectively reflect the ability of aluminum foil to resist high-temperature deformation during brazing.

[0003] At present, the Chinese patent with the existing patent publication number: CN110257673A discloses an aluminum foil for producing automobile heat dissipation composite fins and its preparation method. The material includes a core material and two layers of skin material. The aluminum foil for the composite fin is a part of the automobile heat exchanger. The aluminum foil skin material for the composite fin has a low melting point. By utilizing the low melting point of the skin material, brazing is performed at a certain high temperature. The fin skin material reaches the melting point and melts, thereby realizing the combination of the fin core material with other components of the heat exchanger. The skin material is composited on the upper and lower surfaces of the core material. The core material and the skin material are continuously cast and rolled to obtain a cast-rolled billet, which is then composited after cold rolling. The preparation method has high production efficiency, high flexibility, and high quality. The coverage rate of the aluminum foil material is more stable. After high-temperature brazing, the aluminum foil has high strength after welding, excellent corrosion resistance, and excellent anti-sagging performance. In summary, the aluminum foil for automobile heat dissipation composite fins prepared by the present invention has excellent performance.

[0004] The existing Chinese patent with the patent publication number CN113136506A discloses a composite fin material for engineering machinery produced by a cold-rolled composite method and a manufacturing method thereof. The composite fin material for engineering machinery comprises a core layer and two upper and lower brazing layers. The core layer and the brazing layer are rolled to form a composite structure. The brazing layer is AA4045 aluminum alloy, and the core layer is AA3003 aluminum alloy. The core layer and the brazing layer are prepared by casting and cold rolling. The core layer and the brazing layer are cold-rolled and composited to obtain a composite fin material for engineering machinery. The preparation method has high production efficiency, high flexibility, high quality, controllable process, good repeatability, and is easy to master. The aluminum foil material prepared by this method has a more stable coverage rate, and the aluminum foil has high strength after high-temperature brazing and excellent corrosion resistance.

[0005] However, during the implementation of the above technical solution, it was found that there were at least the following technical problems:

[0006] Aluminum alloys have been widely used in the field of heat exchangers due to their high mass-to-strength ratio, good heat transfer performance, excellent corrosion resistance and low cost. In recent years, with the continuous advancement of the lightweight process of automobiles, in order to reduce vehicle weight and reduce the manufacturing cost of heat exchangers, the thickness of brazed aluminum foil, which is the material of heat exchanger fins, has shown a trend of thinning. However, during the brazing process of aluminum heat exchangers, such a thin aluminum foil has to be kept in a harsh environment of high temperature of about 600°C and a certain pressure for nearly 10 minutes, and it is easy to collapse, causing the heat exchanger to be scrapped. Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] In view of the deficiencies in the prior art, the present invention provides a composite fin aluminum foil with high anti-droop performance and a processing technology thereof, which solves the technical problem that the prior art easily collapses and causes the heat exchanger to be scrapped.

[0009] (II) Technical solution

[0010] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0011] A composite fin aluminum foil with high anti-sagging performance, the composite fin aluminum foil comprises the following components in percentage by weight:

[0012] Si0.7~0.8%, Mn1.4~1.5%, Zn1.3~1.4%, Zr0.08~0.11%, Fe0.2~0.25%, Cu0.03~0.09%, unavoidable impurities<0.25%, and the balance is Al.

[0013] A method for preparing a composite fin aluminum foil with high anti-droop performance, characterized in that it comprises the following steps:

[0014] Step 1: melt and mix various raw materials including Si0, Mn, Zn, Zr, Fe, Cu and Al in a furnace. The melting temperature of the raw materials Si0, Mn, Zn, Zr, Fe, Cu and Al is 660℃-720℃, and the melting time of the furnace for Si0, Mn, Zn, Zr, Fe, Cu and Al is 4h-8h. The molten liquid is introduced into a mold for solidification to obtain an aluminum alloy composite plate. The solidification time in the mold is 3h-5h. After the aluminum alloy composite plate is demoulded, the surface of the aluminum alloy composite plate needs to be polished;

[0015] Step 2: heat the aluminum alloy composite plate, and then put it into a hot rolling mechanism to hot-roll the aluminum alloy composite plate into a sheet. The temperature of the aluminum alloy composite plate during hot rolling by the hot rolling mechanism is 460°C-540°C, and the thickness of the aluminum alloy composite plate after hot rolling by the hot rolling mechanism is 6mm-8mm;

[0016] Step 3: annealing the hot-rolled aluminum alloy composite plate, wherein the temperature of annealing and heat preservation crystallization is 330°C-500°C, and the heat preservation crystallization time is 2h-4h;

[0017] Step 4: After the annealed aluminum alloy composite plate is placed in a cold rolling mechanism, the aluminum alloy composite plate is cold rolled, and the cold rolling mechanism presses the aluminum alloy composite plate down by 20%-50%;

[0018] Step 5: After the aluminum alloy composite plate is rolled into a sheet structure of an aluminum alloy composite sheet, the aluminum alloy composite sheet is placed in a cutting device for cutting to obtain a composite fin aluminum foil. After the aluminum alloy composite sheet is cut into the composite fin aluminum foil, the cut edge of the composite fin aluminum foil needs to be polished to remove burrs;

[0019] Step six: select several groups of composite fin aluminum foil, put them into the muffle furnace for heating, and heat up with the furnace at a heating rate of 25℃ / min. Take out the device after reaching the set temperature, and then measure the sag value of the sample, the sag value and yield strength change of the rolled composite fin aluminum foil during the heating process, and the change of sag value during the simulated brazing process of composite fins at different temperatures, and record the data. The maximum temperature set in the measurement of the sag value and yield strength change of the rolled composite fin aluminum foil during the heating process is 600℃.

[0020] (III) Beneficial effects

[0021] 1. Increasing the cold rolling reduction can reduce the crystallization start temperature of the composite fin aluminum foil, narrow the temperature range of the accelerated droop stage, and reduce the droop amount in the accelerated droop stage, thereby improving the anti-droop performance of the material and effectively avoiding the harsh environment of constant pressure for nearly 10 minutes, which is prone to collapse and causes the scrapping of the heat exchanger.

[0022] 2. The use of finished product annealing can significantly improve the anti-droop performance of the composite fin aluminum foil. As the finished product annealing temperature increases, the droop value of the composite fin aluminum foil decreases and the anti-droop performance is improved. After the finished product is annealed at 500℃×3h, the anti-droop performance of the composite fin aluminum foil is the best. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings.

[0024] Figure 1 This is a graph showing changes in the sag value and yield strength of the composite fin aluminum foil with 20% rolling reduction during the heating process of the present invention.

[0025] Figure 2 The graph is a variation diagram of the sag value and yield strength of the composite fin aluminum foil with 30% rolling reduction during the heating process of the present invention.

[0026] Figure 3 This is a graph showing changes in the sag value and yield strength of the composite fin aluminum foil with 40% rolling reduction during the heating process of the present invention.

[0027] Figure 4 This is a graph showing the variation of the sag value during the simulated brazing process of the composite fins at different temperatures of the present invention. DETAILED DESCRIPTION

[0028] The embodiment of the present application provides a composite fin aluminum foil with high anti-droop performance and its processing technology. By increasing the cold rolling reduction, the crystallization start temperature of the composite fin aluminum foil can be reduced, the temperature range of the accelerated droop stage can be narrowed, and the droop amount in the accelerated droop stage can be reduced, thereby improving the anti-droop performance of the material, effectively avoiding the severe environment of constant pressure for nearly 10 minutes, which is easy to collapse and cause the scrapping of the heat exchanger; the finished product annealing can significantly improve the anti-droop performance of the composite fin aluminum foil. As the finished product annealing temperature increases, the droop value of the composite fin aluminum foil decreases, and the anti-droop performance is improved. After the finished product is annealed at 500℃×3h, the anti-droop performance of the composite fin aluminum foil is the best.

[0029] Example 1

[0030] In view of the problems existing in the prior art, the present invention provides a composite fin aluminum foil with high anti-sagging performance, and the composite fin aluminum foil comprises the following components in percentage by weight:

[0031] Si0.7%, Mn1.4%, Zn1.3%, Zr0.08%, Fe0.2%, Cu0.03%, unavoidable impurities<0.25%, and the balance is Al.

[0032] A method for preparing a composite fin aluminum foil with high anti-droop performance, comprising the following steps:

[0033] Step 1: melt and mix various raw materials including Si0, Mn, Zn, Zr, Fe, Cu and Al in a furnace. The melting temperature of the raw materials Si0, Mn, Zn, Zr, Fe, Cu and Al is 660°C, and the melting time of the furnace for Si0, Mn, Zn, Zr, Fe, Cu and Al is 4 hours. The molten liquid is introduced into a mold for solidification to obtain an aluminum alloy composite plate. The solidification time in the mold is 3 hours. After the aluminum alloy composite plate is demolded, the surface of the aluminum alloy composite plate needs to be polished;

[0034] Step 2: The aluminum alloy composite plate is subjected to a heating treatment, and then placed in a hot rolling mechanism to hot-roll the aluminum alloy composite plate into a sheet. The temperature at which the aluminum alloy composite plate is heated during the hot rolling process by the hot rolling mechanism is 460° C., and the thickness of the aluminum alloy composite plate after hot rolling by the hot rolling mechanism is 6 mm;

[0035] Step 3: annealing the hot-rolled aluminum alloy composite plate, wherein the annealing and heat preservation crystallization temperature is 330°C and the heat preservation crystallization time is 3h;

[0036] Step 4: After the annealed aluminum alloy composite plate is placed in a cold rolling mechanism, the aluminum alloy composite plate is cold rolled, and the cold rolling mechanism presses the aluminum alloy composite plate by 20%;

[0037] Step 5: After the aluminum alloy composite plate is rolled into a sheet structure of an aluminum alloy composite sheet, the aluminum alloy composite sheet is placed in a cutting device for cutting to obtain a composite fin aluminum foil. After the aluminum alloy composite sheet is cut into the composite fin aluminum foil, the cut edge of the composite fin aluminum foil needs to be polished to remove burrs.

[0038] Example 2

[0039] A composite fin aluminum foil with high anti-sagging performance, the composite fin aluminum foil comprises the following components in percentage by weight:

[0040] Si0.7%, Mn1.4%, Zn1.3%, Zr0.08%, Fe0.2%, Cu0.03%, unavoidable impurities<0.25%, and the balance is Al.

[0041] A method for preparing a composite fin aluminum foil with high anti-droop performance, comprising the following steps:

[0042] Step 1: melt and mix various raw materials including Si0, Mn, Zn, Zr, Fe, Cu and Al in a furnace. The melting temperature of the raw materials Si0, Mn, Zn, Zr, Fe, Cu and Al is 700°C, and the melting time of the furnace for Si0, Mn, Zn, Zr, Fe, Cu and Al is 6 hours. The molten liquid is introduced into a mold for solidification to obtain an aluminum alloy composite plate. The solidification time in the mold is 4 hours. After the aluminum alloy composite plate is demolded, the surface of the aluminum alloy composite plate needs to be polished;

[0043] Step 2: heat the aluminum alloy composite plate, and then put it into a hot rolling mechanism to hot-roll the aluminum alloy composite plate into a sheet. The temperature of the aluminum alloy composite plate during the hot rolling process of the hot rolling mechanism is 500° C., and the thickness of the aluminum alloy composite plate after hot rolling by the hot rolling mechanism is 6 mm;

[0044] Step 3: annealing the hot-rolled aluminum alloy composite plate, wherein the annealing and heat preservation crystallization temperature is 420°C and the heat preservation crystallization time is 3 hours;

[0045] Step 4: After the annealed aluminum alloy composite plate is placed in a cold rolling mechanism, the aluminum alloy composite plate is cold rolled, and the cold rolling mechanism presses the aluminum alloy composite plate by 30%;

[0046] Step 5: After the aluminum alloy composite plate is rolled into a sheet structure of an aluminum alloy composite sheet, the aluminum alloy composite sheet is placed in a cutting device for cutting to obtain a composite fin aluminum foil. After the aluminum alloy composite sheet is cut into the composite fin aluminum foil, the cut edge of the composite fin aluminum foil needs to be polished to remove burrs.

[0047] Example 3

[0048] A composite fin aluminum foil with high anti-sagging performance, the composite fin aluminum foil comprises the following components in percentage by weight:

[0049] Si0.7%, Mn1.4%, Zn1.3%, Zr0.08%, Fe0.2%, Cu0.03%, unavoidable impurities<0.25%, and the balance is Al.

[0050] A method for preparing a composite fin aluminum foil with high anti-droop performance, characterized in that it comprises the following steps:

[0051] Step 1: melt and mix various raw materials including Si0, Mn, Zn, Zr, Fe, Cu and Al in a furnace. The melting temperature of the raw materials Si0, Mn, Zn, Zr, Fe, Cu and Al is 720°C, and the melting time of the furnace for Si0, Mn, Zn, Zr, Fe, Cu and Al is 8 hours. The molten liquid is introduced into a mold for solidification to obtain an aluminum alloy composite plate. The solidification time in the mold is 5 hours. After the aluminum alloy composite plate is demolded, the surface of the aluminum alloy composite plate needs to be polished;

[0052] Step 2: The aluminum alloy composite plate is subjected to a heating treatment, and then placed in a hot rolling mechanism to hot-roll the aluminum alloy composite plate into a sheet. The temperature at which the aluminum alloy composite plate is heated during the hot rolling process by the hot rolling mechanism is 540° C., and the thickness of the aluminum alloy composite plate after hot rolling by the hot rolling mechanism is 6 mm;

[0053] Step 3: annealing the hot-rolled aluminum alloy composite plate, wherein the annealing and heat preservation crystallization temperature is 500°C and the heat preservation crystallization time is 3 hours;

[0054] Step 4: After the annealed aluminum alloy composite plate is placed in a cold rolling mechanism, the aluminum alloy composite plate is cold rolled, and the cold rolling mechanism presses the aluminum alloy composite plate by 50%;

[0055] Step 5: After the aluminum alloy composite plate is rolled into a sheet structure of an aluminum alloy composite sheet, the aluminum alloy composite sheet is placed in a cutting device for cutting to obtain a composite fin aluminum foil. After the aluminum alloy composite sheet is cut into the composite fin aluminum foil, the cut edge of the composite fin aluminum foil needs to be polished to remove burrs.

[0056] Example 4

[0057] The composite fin aluminum foil prepared in combination with Examples 1-3 was placed in a muffle furnace for heating, and the temperature was raised with the furnace at a heating rate of 25°C / min. After reaching the set temperature, the device was taken out, and then the sag value of the sample was measured, and the sag value and yield strength changes of the composite fin aluminum foil during the heating process of the rolling reduction and the changes in the sag value during the simulated brazing process of the composite fins at different temperatures were measured, and the data were recorded; the sag behavior of the composite fin aluminum foil with different final rolling reductions of 20%, 30%, and 50% during the brazing heating process and the corresponding room temperature yield strength, as shown in FIG. Figure 1-3 It can be seen that the sag value at 600℃ for 10 minutes decreases with the increase of the reduction, and the anti-sag performance is getting better and better. When the final rolling reduction of the composite fin aluminum foil is 50%, the anti-sag performance is the best. In the recovery stage, the yield strength of the material decreases slowly. When the material begins to recrystallize, the yield strength begins to decrease significantly. Therefore, Figure 1-3It can be obtained that the recrystallization start temperatures of the composite fin aluminum foil with 20%, 30% and 50% reduction are 550℃, 475℃, 450℃ and 425℃ respectively;

[0058] Combined with the yield strength change of composite fin aluminum foil during simulated brazing process, Figure 3 The sag during the heating process is divided into three stages: (1) the non-sag stage (room temperature to 200°C), when the material is still in a work-hardening state and the sag of the material is almost zero; (2) the accelerated sag stage (200°C to the recrystallization start temperature), this stage is basically consistent with the material's recovery temperature range, the material's sag value increases at a relatively fast rate, and when the recovery process is over, the accelerated sag stage also ends quickly; (3) the slow sag stage (above the recrystallization start temperature), when the sag value of the fin material changes little. From the sag behavior of the fin material with different final rolling reductions, it can be seen that the stage with the greatest impact on the material sag process is the second stage. The greater the final rolling reduction, the lower the recrystallization start temperature, the narrower the recovery temperature range, the shorter the accelerated sag stage, and the smaller the contribution of the accelerated sag stage to the sag during the brazing process;

[0059] The TD surface grain structure of composite fin aluminum foil with different reductions when kept at 600℃ for 10min, the length of TD surface grains along RD direction is 300~500μm with different final rolling reductions of 20%, 30%, and 50%, and the size of 1~2 grains in thickness direction;

[0060] Figure 4 The drooping behavior of the composite fin aluminum foil after annealing of different finished products during the brazing heating process is shown in Figure 2. Figure 4 It can be seen that the annealing of the finished product can significantly improve the anti-droop performance of the fin material. With the increase of the annealing temperature of the finished product, the droop value of the composite fin aluminum foil decreases, and the anti-droop performance is improved. After the finished product is annealed at 500℃×3h, the anti-droop performance of the fin material is the best.

[0061] During the material recovery process, the deformation dislocation is thermally activated and re-driven. At this time, the dislocation is affected by the stress generated by the gravity load, resulting in high-temperature creep, causing the material to gradually bend and sag. Figure 4It can be seen that under the same temperature and stress level, the composite fin aluminum foil in the cold-rolled state and after the finished product annealing exhibit completely different droop behaviors. When the finished fin material is annealed at 500℃×3h, the droop of the material when the brazing temperature is raised to 400℃ is close to zero, which indicates that the material produces less creep under the action of gravity alone; while the cold-rolled fin material droops significantly in the recovery stage (400℃) of the brazing process, and the material produces more creep. It can be seen that the droop of the fin material during the brazing process is mainly affected by the deformation dislocation inside the material before brazing. When the fin material is annealed at 500℃×3h, the material is fully recrystallized, and there are almost no deformation dislocations inside the material before brazing; while for the cold-rolled fin material, there are a large number of deformation dislocations inside the material before brazing. During the brazing process, a large number of deformation dislocations are thermally activated, and these dislocations become movable dislocation sources in the creep process, so that only a small stress is required to make the creep proceed;

[0062] Finally, it can be concluded that: (1) the sag during the brazing heating process is divided into three stages: the non-sag stage (room temperature ~ 200℃), at this time, the mechanical properties of the composite fin aluminum foil do not change; the accelerated sag stage (200℃ ~ recrystallization start temperature), the accelerated sag is caused by creep promoted by the cold working microstructure recovery process, and the sag in this stage accounts for most of the sag value in the entire heating process; the slow sag stage (above the recrystallization start temperature), at this time the creep rate of the material is small, and its contribution to the sag value in the entire heating process is small.

[0063] (2) Increasing the cold rolling reduction can reduce the recrystallization start temperature of the composite fin aluminum foil, narrow the temperature range of the accelerated droop stage, and reduce the droop amount in the accelerated droop stage, thereby improving the anti-droop performance of the material.

[0064] (3) Finished product annealing can reduce the droop rate of the composite fin aluminum foil in the accelerated droop stage, thereby improving the material's anti-droop performance.

[0065] Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the scope of protection of the present invention.

Claims

1. A composite fin aluminum foil with high anti-sagging performance, characterized in that: The composite fin aluminum foil comprises the following components in percentage by weight: Si 0.7~0.8%, Mn 1.4~1.5%, Zn 1.3~1.4%, Zr 0.08~0.11%, Fe 0.2~0.25%, Cu 0.03~0.09%, unavoidable impurities <0.25%, and the balance is Al.

2. A processing technology for composite fin aluminum foil with high anti-droop performance, characterized in that: The composite fin aluminum foil component according to claim 1 is used, comprising the following steps: Step 1: melt and mix various raw materials including SiO, Mn, Zn, Zr, Fe, Cu and Al in a furnace, introduce the molten liquid into a mold for solidification, and obtain an aluminum alloy composite plate; Step 2: heat the aluminum alloy composite plate, and then put it into a hot rolling mechanism to hot roll the aluminum alloy composite plate into sheets; Step 3: annealing the hot-rolled aluminum alloy composite plate; Step 4: After placing the annealed aluminum alloy composite plate into a cold rolling mechanism, the aluminum alloy composite plate is subjected to cold rolling treatment; Step 5: After the aluminum alloy composite plate is rolled into a sheet structure of an aluminum alloy composite sheet, the aluminum alloy composite sheet is placed in a cutting device for cutting to obtain a composite fin aluminum foil; Step six: select several groups of composite fin aluminum foil, put them into the muffle furnace for heating, take them out after heating, test the sag value of the composite fin aluminum foil, and the changes in the sag value and yield strength of the rolled composite fin aluminum foil during the heating process, as well as the changes in the sag value during the simulated brazing process of the composite fins at different temperatures, and record the data.

3. The processing technology of the composite fin aluminum foil with high anti-droop performance as claimed in claim 2 is characterized in that: In the step 1, the melting temperature of the raw materials SiO2, Mn, Zn, Zr, Fe, Cu and Al is 660°C-720°C, and the melting time of the furnace for SiO2, Mn, Zn, Zr, Fe, Cu and Al is 4h-8h.

4. The processing technology of the composite fin aluminum foil with high anti-droop performance as claimed in claim 2 is characterized in that: The time for solidifying the molten liquid into the mold is 3h-5h. After the aluminum alloy composite plate is demoulded, the surface of the aluminum alloy composite plate needs to be polished.

5. The processing technology of the composite fin aluminum foil with high anti-droop performance as claimed in claim 2 is characterized in that: In the step 2, the temperature at which the aluminum alloy composite plate is heated during hot rolling by the hot rolling mechanism is 460° C.-540° C., and the thickness of the aluminum alloy composite plate after hot rolling by the hot rolling mechanism is 6 mm-8 mm.

6. The processing technology of the composite fin aluminum foil with high anti-sagging performance as claimed in claim 2 is characterized in that: The temperature of the annealing and heat preservation crystallization in the step 3 is 330°C-500°C, and the heat preservation crystallization time is 2h-4h.

7. The processing technology of the composite fin aluminum foil with high anti-droop performance as claimed in claim 2 is characterized by: In the fourth step, the cold rolling mechanism presses the aluminum alloy composite plate down by 20%-50%.

8. The processing technology of the composite fin aluminum foil with high anti-sagging performance as claimed in claim 2 is characterized by: After the aluminum alloy composite sheet is cut into composite fin aluminum foil in step 5, the cut edge of the composite fin aluminum foil needs to be polished to remove burrs.

9. The processing technology of the composite fin aluminum foil with high anti-sagging performance as claimed in claim 2 is characterized by: In the step six, the device is placed in a muffle furnace and heated up with the furnace at a heating rate of 25° C. / min. After reaching the set temperature, the device is taken out and then the sag value of the sample is measured.

10. The processing technology of the composite fin aluminum foil with high anti-sagging performance as claimed in claim 2 is characterized in that: The maximum temperature set in step 6 for measuring the sag value and yield strength change of the rolled composite fin aluminum foil during the heating process is 600°C.

Images