Aluminum alloy material, preparation method and application thereof

Abstract

The application discloses an aluminum alloy material and a preparation method and application thereof. The aluminum alloy material is composed of the following components in percentage by mass: Mn 0.5-2%, Cu 0-0.5%, Zn 0-1.5%, Mg 0-1%, Zr 0-0.5%, Ti 0.01-0.6%, RE 0.05-0.4%, and the balance of Al and inevitable impurities. The aluminum alloy material provided by the application is used for brazing, and the yield strength RP0.2 of the aluminum alloy material in an annealed state (O state) is greatly improved to be greater than or equal to 70 MPa, so that the requirements of high corrosion resistance, high anti-sagging property and good brazing property of a heat exchanger are met, and the application has great significance for improving the strength and reliability of a radiator.

Description

Technical Field

[0001] This invention relates to an aluminum alloy material, its preparation method, and its application, belonging to the field of materials science and technology. Background Technology

[0002] Radiators, as crucial heat exchange devices in the machinery industry, utilize the exchange of heat between a high-temperature medium (such as liquid or steam) and a low-temperature medium to achieve cooling. They are widely used in the automotive, home appliance, and aerospace industries, with a particularly significant application in the automotive sector. As a core component of the automotive engine cooling system, the quality of automotive radiators has a substantial impact on the efficient operation of the engine and is closely related to the vehicle's heat dissipation performance and safety. Due to the trend towards environmentally friendly, economical, and lightweight automotive designs, automotive radiators are gradually abandoning traditional copper alloys in favor of lightweight aluminum alloys. Currently, the production process for domestically manufactured aluminum automotive radiators mostly involves first brazing the core, then sealing the inlet and outlet chambers to the core, and finally welding the entire radiator together. Therefore, the key processes and challenges in producing aluminum alloy radiators lie in the brazing of the aluminum alloy.

[0003] The 3003 aluminum alloy currently in use has a low yield strength (30-50MPa) in the annealed state, which easily leads to the overall collapse of the radiator or the occurrence of incomplete welds and detachment during the welding process. Therefore, how to develop new aluminum alloy materials for brazing with high yield strength to meet the requirements of high anti-sagging and good brazing properties of heat exchangers has become an urgent problem to be solved. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the first objective of the present invention is to provide an aluminum alloy material with excellent yield strength.

[0005] The second objective of this invention is to provide a method for preparing aluminum alloy materials.

[0006] The third objective of this invention is to provide an application of an aluminum alloy material, which, when used as a brazing material, can meet the requirements of high anti-sagging properties and good brazing performance of heat exchangers.

[0007] To achieve the above objectives, the present invention adopts the following technical solution.

[0008] The present invention discloses an aluminum alloy material, which, by mass percentage, has the following composition: Mn 0.5-2%, Cu 0-0.5%, Zn 0-1.5%, Mg 0-1.1%, Zr 0-0.5%, Ti 0.01-0.6%, RE 0.05-0.4%, with the balance being Al and unavoidable impurities.

[0009] The aluminum alloy material of this invention incorporates rare earth elements, utilizing their purifying, refining, and strengthening effects, which aligns with the general principles of rare earth elements in aluminum alloys. During solidification, due to the high diffusion rate, rare earth elements accumulate in large quantities at the solid-liquid interface front, constrained by diffusion kinetics, leading to solute redistribution. This increases supercooling during solidification, intensifies branching, and refines the dendritic network, thus refining the alloy's grain size. Simultaneously, a stable Al3RE(L12) precipitate is formed. This precipitate not only strengthens the alloy itself but also pins dislocations and grain boundaries, providing solid solution strengthening. Furthermore, the simultaneous addition of zinc and magnesium forms MgZn2 as a strengthening phase, significantly enhancing the alloy's strength. Trace amounts of Zr effectively improve the alloy's properties. Under suitable annealing processes, Zr precipitates uniformly from the solid solution along with RE elements, and recombines with RE elements to form metastable Al3Zr and Al3(RE,Zr)(L12) phases. These phases are finely and uniformly distributed in the matrix. The metastable Al3Zr and Al3(RE,Zr) phases exhibit good coherence with the Al matrix. When the peritectic reaction occurs in the alloy, α-Al nucleates closely adjacent to these fine Al3Zr particles, and Zr and RE play a role in refining the grain size. Simultaneously, Al3Zr and Al3(RE,Zr) particles hinder recrystallization nucleation in the alloy, pinning dislocations and grain boundaries, suppressing the recrystallization process, and ultimately refining the grain size and improving the alloy's yield strength.

[0010] Furthermore, the aluminum alloy material, by mass percentage, has the following composition: Mn 0.52–1.86%, Cu 0.02–0.45%, Zn 0.08–1.28%, Mg 0.04–1.02%, Zr 0.01–0.42%, Ti 0.01–0.49%, RE 0.12–0.39%, with the balance being Al and unavoidable impurities.

[0011] The inventors discovered that when the amount of MgZn2 precipitated in the alloy is between 0.5% and 12%, the alloy strength increases with the increase of precipitated phase, but the stress corrosion resistance decreases. However, by controlling the composition of Zn and Mg in the alloy within the above range, the amount of MgZn2 precipitated in the alloy is appropriate, resulting in the optimal overall performance of the alloy.

[0012] Furthermore, the RE is selected from at least one of Sc, Er, La, Ce, Y, and Yb.

[0013] In this invention, among the unavoidable impurities, the aluminum alloy is required to have a Si content of less than 0.4%, an Fe content of less than 0.6%, a single other element content of less than 0.05%, and a combined other element content of less than 0.15%.

[0014] Furthermore, the aluminum alloy material in the annealed state (O state) has an RP0.2 ≥ 70 MPa.

[0015] The present invention also provides a method for preparing aluminum alloy material, wherein each metal raw material is smelted according to a design ratio to obtain a melt, the melt is cast to obtain an ingot, the ingot is homogenized to obtain a homogenized billet, the homogenized billet is hot-extruded to obtain an extruded billet, and the extruded billet is annealed to obtain the aluminum alloy material.

[0016] Furthermore, according to the design proportions, shavings of aluminum, recycled materials, pure zinc, pure magnesium, pure zinc, Al-10Mn, Al-20Cu, Al-4Zr, and Al-5RE are prepared.

[0017] In this invention, Al-10Mn refers to the molar fraction of Mn in Al-10Mn being 10%.

[0018] The inventors discovered that by using the aforementioned raw materials, the segregation of alloying elements in ingots can be significantly reduced.

[0019] Furthermore, the smelting process involves first feeding crushed aluminum and recycled materials to the bottom of the furnace, then adding aluminum ingots on top and melting them to obtain molten aluminum. Zinc ingots, Al-10Mn, Al-20Cu, and Al-4Zr are then added and melted to obtain molten aluminum alloy. The mixture is stirred, and when the temperature of the molten aluminum alloy reaches 730–750°C, slag is skimmed off. Finally, the mixture is refined at 730–740°C for 15–20 minutes.

[0020] In the smelting process of this invention, zinc and magnesium are added as pure metals, aluminum is added as scrap aluminum, recycled material, or aluminum ingots, and other metals are added as intermediate alloys. The smelting is carried out in the manner described above, and the resulting alloy has a uniform composition and no segregation.

[0021] In actual operation, when loading the furnace, first put the broken aluminum and recycled materials to the bottom of the furnace to protect it, and then add the aluminum ingots on top. The aluminum liquid temperature setting is as follows: the aluminum liquid temperature in the crucible furnace should be set at 760℃, and the furnace gas temperature should be controlled at 900℃. After the aluminum liquid in the crucible reaches 700℃ and is completely melted, start to add zinc ingots, Al-10Mn, Al-20Cu, and Al-4Zr master alloys in sequence and evenly, making sure they are not exposed above the liquid surface or close to the furnace bottom. After all the furnace materials have melted, add magnesium ingots, making sure they are not exposed above the liquid surface, and turn on the magnetic stirrer. When the aluminum liquid temperature is between 730 and 750℃, remove the surface slag. Safety measures: the master alloy materials should be gently added to the crucible; excessive impact may cause the crucible to break. Tools that come into contact with the aluminum liquid must be thoroughly dried before use. Then, take samples for chemical composition analysis: if the chemical composition is not up to standard, adjust the added elements according to the analysis results, using the same method as above, and then degas and stir until it is up to standard. Record the sample number: use an oil-based pen to write the number on the sample clearly and accurately according to the batching list. Finally, after the composition meets the requirements, the mixture is transferred to a static holding furnace and thoroughly stirred once. High-purity argon gas is then used for refining, with the bubble height controlled within 100mm. The refining time is 15–20 minutes, and the refining temperature is controlled at 730–740℃.

[0022] Furthermore, the casting is a semi-continuous casting, the casting temperature is 690-710℃, Al-5Ti-1B wire is connected, double wire feeding is used, and the wire feeding speed is 40-50mm / min.

[0023] In actual operation, the filter plate adopts a 30ppi+40ppi dual-stage filtration during casting.

[0024] In a preferred embodiment, the homogenization process involves uniformly heating to 600–650°C over 1–3 hours, followed by holding at that temperature for 10–18 hours. This homogenization process reduces the presence of compounds in the microstructure after homogenization.

[0025] Furthermore, during the hot extrusion, the preheating temperature of the homogenized billet is 450–480°C, the preheating holding time of the homogenized billet is 90–180 min, the preheating temperature of the die is 450–500°C, the preheating holding time of the die is 120–240 min, and the extrusion rate is 2–6 mm / s.

[0026] In this invention, by controlling the hot extrusion parameters within the aforementioned range, the final alloy material exhibits optimal performance. If the preheating temperature and time are too low, the deformation resistance during extrusion is too high, resulting in the ingot being unable to be extruded; if they are too high, the ingot will overheat, reducing its performance. If the extrusion speed is too low, production efficiency is low, and the ingot's cooling deformation resistance is too high, making it impossible to extrude; if the speed is too high, cracks such as edge cracking will occur during extrusion.

[0027] Furthermore, the hot extrusion is a forward hot extrusion.

[0028] Furthermore, the annealing process is as follows: the temperature is raised to 380-420℃ at a rate of 50-100℃ / h, held for 2-3 hours, and then cooled in the furnace at a rate of no more than 30℃ / h to below 260℃, and then air-cooled after being removed from the furnace.

[0029] In this invention, a full annealing process is employed, involving heating to a temperature above the phase transformation point and holding at that temperature to transform the alloy into a single-phase solid solution. Then, slow cooling is used to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating work hardening. Furthermore, this annealing process allows Zr to precipitate uniformly from the solid solution along with RE elements, improving the alloy's yield strength. Of course, the annealing parameters need to be effectively controlled. If the temperature is too low or the speed is too fast, incomplete annealing will result in residual processing stress, affecting subsequent welding. If the temperature is too high, abnormal grain growth will occur, reducing performance.

[0030] The present invention also provides an application of aluminum alloy material, wherein the aluminum alloy material is used as a brazing material.

[0031] Beneficial effects

[0032] The novel brazing aluminum alloy material and its preparation method provided by this invention are scientifically and rationally designed. Firstly, rare earth elements are added to the national standard composition, utilizing their purifying, refining, and strengthening effects on the aluminum alloy, which aligns with the general characteristics of rare earth elements in aluminum alloys. During solidification, due to the high diffusion rate, a large amount of rare earth elements accumulates at the solid-liquid interface front due to the limitations of diffusion kinetics, causing solute redistribution. This increases the supercooling of the alloy during solidification, intensifying the branching process and thus refining the dendritic network cells and the alloy grains. Simultaneously, stable L12 precipitates are formed. These precipitates not only strengthen the alloy themselves but also pin dislocations and grain boundary movement, providing solid solution strengthening. Based on this, corresponding smelting processes are developed, including smelting, semi-continuous casting, and ingot homogenization processes, giving it a high-performance chemical basis. Based on the above, by setting a reasonable forward hot extrusion and full annealing process, a brazing aluminum alloy with excellent mechanical properties (annealed state RP0.2≥70MPa) was obtained, which meets the requirements of high corrosion resistance, high anti-sagging and good brazing properties of heat exchangers.

[0033] Of course, any product implementing this invention does not necessarily need to achieve all of the above advantages at the same time. Attached Figure Description

[0034] Figure 1 The process flow diagram of this invention. Detailed Implementation

[0035] The technical solutions will now be clearly and completely described in conjunction with embodiments of the present invention. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0036] A novel aluminum alloy material for brazing has the following chemical composition (by weight percentage): Mn (0.5-2%), Cu (0-0.5%), Zn (0-1.5%), Mg (0-1%), Zr (0-0.5%), Ti (0.01-0.6%), RE (0.05-0.4%), with the balance being Al and unavoidable impurities.

[0037] The aluminum alloy material for brazing has an RP0.2 ≥ 70 MPa in the annealed state (O state).

[0038] The aluminum alloy material used for brazing has a Si content of less than 0.4%, an Fe content of less than 0.6%, a single other element content of less than 0.05%, and a total other element content of less than 0.15%.

[0039] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0040] 1) In drying metal and alloy raw materials, alloying elements Mn, Cu, Zr and RE are added in the form of master alloys Al-Mn, Al-Cu, Al-Zr and Al-RE respectively, and Ti is added to the alloy in the form of Al-Ti-B, so as to minimize the segregation of alloying elements in the ingot;

[0041] 2) Melt, semi-continuously cast, homogenize the ingot, perform forward hot extrusion, and fully anneal to obtain the above-mentioned aluminum alloy material.

[0042] The specific smelting and semi-continuous casting process for manufacturing aluminum alloy materials for brazing is as follows:

[0043] 1) Charge proportioning calculation: a) Aluminum, zinc, and magnesium ingots are added as pure metals. Alloying elements Mn, Cu, Zr, and RE are added as Al-10Mn, Al-20Cu, Al-4Zr, and Al-10RE master alloys, respectively, to reduce alloy element segregation in the ingots. c) Record the weight of the materials on the batching sheet and record the number; d) Dry the materials used at 200℃ before use; e) Calculate the batching based on the chemical composition by mass percentage.

[0044] 2) Weighing of alloy materials: a. Weigh aluminum ingots using an electronic scale; b. Weigh intermediate alloys and alloying elements using an electronic scale; c. Allowable weight tolerance of ±0.5%.

[0045] 3) When loading the furnace, first place the scrap aluminum and recycled materials at the bottom to protect the furnace bottom. Then add the aluminum ingots on top. Set the aluminum liquid temperature: 760℃ for the crucible furnace, and control the furnace gas temperature at 900℃. After the aluminum liquid in the crucible has completely melted at 700℃, begin to add zinc ingots, Al-10Mn, Al-20Cu, and Al-4Zr master alloys in sequence and evenly, ensuring they are not exposed above the liquid surface or pressed against the furnace bottom. After all the materials have melted, add magnesium ingots, ensuring they are not exposed above the liquid surface, and turn on the magnetic stirrer. When the aluminum liquid temperature is between 730 and 750℃, skim off any surface slag. Safety measures: Gently add the master alloy materials into the crucible; excessive impact can cause the crucible to break. Tools that come into contact with the molten aluminum must be thoroughly dried before use.

[0046] 4) Sampling and chemical composition analysis: If the chemical composition is unqualified, adjust the added elements according to the analysis results, using the same method as above, and then degas and stir until qualified. Record the sample number: Use an oil-based pen to write the number on the sample clearly and accurately according to the ingredient list.

[0047] 5) After the composition meets the requirements, transfer it to a static holding furnace and stir thoroughly once. Refine with high-purity argon gas, controlling the bubble height to within 100mm. The refining time is 15–20 minutes, and the refining temperature is controlled at 730–740℃.

[0048] 6) Measure the temperature of the molten aluminum at the outlet of the flow channel using a thermocouple and control it at 690~710℃. Connect the filter plate (using a 30ppi+40ppi dual-stage filter) to Al-5Ti-1B wire, using double-wire feeding at a speed of 45mm / min.

[0049] The specific embodiments of the present invention are as follows:

[0050] Example 1

[0051] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is shown in Table 1 below:

[0052] Table 1

[0053]

[0054] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0055] Furnace charge proportioning calculation: a) Aluminum, zinc, and magnesium ingots are added as pure metals. Alloying elements Mn, Cu, Zr, and RE are added as Al-10Mn, Al-20Cu, Al-4Zr, and Al-10RE master alloys, respectively, to reduce alloy element segregation in the ingots. c) Record the weight of the materials on the batching sheet and assign a number; d) Dry all materials at 200℃ before use; 5) Calculate the batching based on the chemical composition by mass percentage.

[0056] Weighing of alloy materials: a. Aluminum ingots are weighed using an electronic scale; b. Intermediate alloys and alloying elements are weighed using an electronic scale; c. Allowable weight tolerance of ±0.5%.

[0057] When loading the furnace, first place the broken aluminum and small materials at the bottom to protect it. The aluminum molten metal temperature setting is 760℃ for the crucible furnace, and the furnace gas temperature should be controlled at 900℃. After the aluminum molten metal in the crucible has completely melted at 700℃, begin to add the Al-10Mn, Al-20Cu, and Al-4Zr master alloys sequentially and evenly, ensuring they are not exposed above the molten metal surface or pressed against the furnace bottom. After all the materials have melted, turn on the magnetic stirrer. When the aluminum molten metal temperature reaches 740℃, skim off any surface slag. Safety precautions: Gently add the master alloy materials into the crucible; excessive impact can cause the crucible to break. Tools that come into contact with the molten aluminum must be thoroughly dried before use.

[0058] Chemical composition analysis of samples: If the chemical composition is unqualified, adjust the added elements according to the analysis results, using the same method as above, and then degas and stir until qualified. Record sample numbers: Use an oil-based pen to write the numbers on the sample clearly and accurately according to the ingredient list.

[0059] After the composition meets the requirements, the mixture is transferred to a static holding furnace and thoroughly stirred once. High-purity argon gas is then used for refining, with the bubble height controlled within 100mm. The refining time is 15 minutes, and the refining temperature is controlled at 735℃.

[0060] The temperature of the molten aluminum at the outlet of the flow channel was measured using a thermocouple and controlled at 700℃. An Al-5Ti-1B wire was connected to the filter plate (using a 30ppi + 40ppi dual-stage filtration system) and fed using a double-wire system at a speed of 45mm / min.

[0061] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is raised to 630℃ at a uniform rate within 2 hours, and then held for 14 hours for homogenization treatment.

[0062] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 470℃, holding time: 120min; Die heating temperature: 475℃, holding time: 180min; Extrusion rate: 4mm / s.

[0063] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 400℃ at a rate of 80℃ / h, hold for 2.5h, then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃, and finally air-cool after removal from the furnace.

[0064] Example 2

[0065] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is as described in Example 1.

[0066] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0067] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is uniformly raised to 600℃ within 1 hour, and then held for 18 hours for homogenization treatment.

[0068] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 480℃, holding time: 90min; Die heating temperature: 450℃, holding time: 240min; Extrusion rate: 2mm / s.

[0069] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 380℃ at a rate of 50℃ / h, hold for 3 hours, and then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃. Remove from the furnace and air cool.

[0070] Example 3

[0071] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is as described in Example 1.

[0072] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0073] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is raised to 650℃ at a uniform rate within 3 hours, and then held for 10 hours for homogenization treatment.

[0074] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 450℃, holding time: 180min; Die heating temperature: 500℃, holding time: 120min; Extrusion rate: 6mm / s.

[0075] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 420℃ at a rate of 100℃ / h, hold for 2 hours, and then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃. Remove from the furnace and air cool.

[0076] Example 4

[0077] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is shown in Table 2 below:

[0078] Table 2

[0079]

[0080]

[0081] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0082] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is raised to 630℃ at a uniform rate within 2 hours, and then held for 14 hours for homogenization treatment.

[0083] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 470℃, holding time: 120min; Die heating temperature: 475℃, holding time: 180min; Extrusion rate: 4mm / s.

[0084] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 400℃ at a rate of 80℃ / h, hold for 2.5h, then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃, and finally air-cool after removal from the furnace.

[0085] Example 5

[0086] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is as described in Example 4.

[0087] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0088] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is uniformly raised to 600℃ within 1 hour, and then held for 18 hours for homogenization treatment.

[0089] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 480℃, holding time: 90min; Die heating temperature: 450℃, holding time: 240min; Extrusion rate: 2mm / s.

[0090] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 380℃ at a rate of 50℃ / h, hold for 3 hours, and then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃. Remove from the furnace and air cool.

[0091] Example 6

[0092] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is as described in Example 4.

[0093] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0094] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is raised to 650℃ at a uniform rate within 3 hours, and then held for 10 hours for homogenization treatment.

[0095] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 450℃, holding time: 180min; Die heating temperature: 500℃, holding time: 120min; Extrusion rate: 6mm / s.

[0096] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 420℃ at a rate of 100℃ / h, hold for 2 hours, and then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃. Remove from the furnace and air cool.

[0097] Example 7

[0098] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is shown in Table 3 below:

[0099] Table 3

[0100]

[0101] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0102] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is raised to 630℃ at a uniform rate within 2 hours, and then held for 14 hours for homogenization treatment.

[0103] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 470℃, holding time: 120min; Die heating temperature: 475℃, holding time: 180min; Extrusion rate: 4mm / s.

[0104] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 400℃ at a rate of 80℃ / h, hold for 2.5h, then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃, and finally air-cool after removal from the furnace.

[0105] Example 8

[0106] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is as described in Example 7.

[0107] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0108] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is uniformly raised to 600℃ within 1 hour, and then held for 18 hours for homogenization treatment.

[0109] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 480℃, holding time: 90min; Die heating temperature: 450℃, holding time: 240min; Extrusion rate: 2mm / s.

[0110] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 380℃ at a rate of 50℃ / h, hold for 3 hours, and then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃. Remove from the furnace and air cool.

[0111] Example 9

[0112] This embodiment provides a novel aluminum alloy material for brazing, the chemical composition of which is as described in Example 7.

[0113] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0114] Homogenization process: To reduce the presence of compounds in the microstructure after ingot homogenization, the temperature is raised to 650℃ at a uniform rate within 3 hours, and then held for 10 hours for homogenization treatment.

[0115] Forward hot extrusion process: Preheating temperature and time, as well as extrusion speed, are crucial factors in the extrusion process. Ingot heating temperature: 450℃, holding time: 180min; Die heating temperature: 500℃, holding time: 120min; Extrusion rate: 6mm / s.

[0116] Full annealing process: Heat to a temperature above the phase transformation point and hold at that temperature to transform the alloy into a single-phase solid solution. Then, slowly cool to ensure the diffusion of solid solution decomposition and second-phase particle aggregation, eliminating cold work hardening. Heat to 420℃ at a rate of 100℃ / h, hold for 2 hours, and then cool in the furnace at a rate not exceeding 30℃ / h until below 260℃. Remove from the furnace and air cool.

[0117] Comparative Example 1

[0118] Comparative Example 1 provides 3003 aluminum alloy material according to the national standard GB / T3190-2020. The chemical composition of this material is shown in Table 4 below:

[0119] Table 4

[0120]

[0121] In Comparative Example 1 above, the 3003 aluminum alloy material differs from that in Example 1 only in composition; the preparation method and other conditions are the same as in Example 1.

[0122] Comparative Example 2

[0123] Comparative Example 2 provides a novel aluminum alloy material for brazing, which has the same chemical composition as Experimental Example 1.

[0124] The preparation method of the above-mentioned novel aluminum alloy material for brazing includes the following steps:

[0125] The calculation of furnace charge ratio, weighing of alloy materials, loading of furnace, and chemical composition analysis of samples are all the same as in Example 1.

[0126] The casting is a semi-continuous casting process, with a casting temperature of 660℃. Al-5Ti-1B wire is attached, and a double-wire feeding method is used with a feeding speed of 40-50 mm / min.

[0127] During the casting process, the casting temperature was too low, causing the flow to stop and the casting to fail. As a result, Comparative Example 2 did not yield any performance results.

[0128] Comparative Example 3

[0129] Comparative Example 3 provides a novel aluminum alloy material for brazing, which has the same chemical composition as Experimental Example 1.

[0130] The preparation method of the above-mentioned novel aluminum alloy material for brazing is the same as that in Example 1, except that the homogenization process is different from that in Example 1.

[0131] The homogenization process involves uniformly heating the temperature to 600-650℃ within 1-3 hours, and then holding it at that temperature for 8 hours.

[0132] Comparative Example 4

[0133] Comparative Example 4 provides a novel aluminum alloy material for brazing, which has the same chemical composition as Experimental Example 1.

[0134] The preparation method of the above-mentioned novel aluminum alloy material for brazing is the same as that of Example 1, except that the hot extrusion process is different from that of Example 1.

[0135] During hot extrusion, the preheating temperature of the homogenized billet is 500℃, the preheating holding time of the homogenized billet is 90-180min, the preheating temperature of the die is 450-500℃, the preheating holding time of the die is 120-240min, and the extrusion rate is 2-6mm / s.

[0136] Comparative Example 5

[0137] Comparative Example 5 provides a novel aluminum alloy material for brazing, which has the same chemical composition as Experimental Example 1.

[0138] The preparation method of the above-mentioned novel aluminum alloy material for brazing is the same as that of Example 1, except that the annealing process is different from that of Example 1.

[0139] The annealing process is as follows: heat up to 450℃ at a rate of 50-100℃ / h, hold for 2-3 hours, cool down in the furnace at a rate of no more than 30℃ / h until below 260℃, and then air cool after removal from the furnace.

[0140] The performance of aluminum alloy materials from Examples 1 to 9 and Comparative Examples 1, 3-5 after complete annealing was tested according to GB / T 228.1-2021. The test results are shown in Table 5.

[0141] Table 5

[0142]

[0143]

[0144] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementation methods. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A method of producing an aluminum alloy material, characterized by: According to the designed proportion, the metal raw materials are melted to obtain a melt, the melt is cast to obtain an ingot, the ingot is subjected to homogenization treatment to obtain a homogenization blank, the homogenization blank is subjected to hot extrusion to obtain an extrusion blank, and the extrusion blank is subjected to annealing treatment to obtain the aluminum alloy material; The casting is semi-continuous casting, the temperature of the casting is 690-710 DEG C, the Al-5Ti-1B wire is connected, the double-wire feeding is adopted, and the feeding speed is 40-50 mm / min; The homogenization treatment process is that the temperature is uniformly increased to 600-650 DEG C within 1-3 h, and then the temperature is kept for 10-18 h; During the hot extrusion, the preheating temperature of the homogenization blank is 450-480 DEG C, the preheating holding time of the homogenization blank is 90-180 min, the preheating temperature of the die is 450-500 DEG C, the preheating holding time of the die is 120-240 min, and the extrusion speed is 2-6 mm / s; The hot extrusion is forward hot extrusion; The annealing treatment process is that the temperature is increased to 380-420 DEG C at a rate of 50-100 DEG C / h, the temperature is kept for 2-3 h, then the temperature is decreased to below 260 DEG C at a rate of not more than 30 DEG C / h, and the furnace is discharged and air-cooled; The aluminum alloy material comprises the following components in percentage by mass: Mn 0.5-2%, Cu 0.02-0.5%, Zn 0.08-1.5%, Mg 0.04-1.1%, Zr 0.01-0.5%, Ti 0.01-0.6%, RE 0.05-0.4%, and the balance of Al and inevitable impurities.

2. The method of making an aluminum alloy material of claim 1, wherein: The aluminum alloy material comprises the following components in percentage by mass: Mn 0.52-1.86%, Cu 0.02-0.45%, Zn 0.08-1.28%, Mg 0.04-1.02%, Zr 0.01-0.42%, Ti 0.01-0.49%, RE 0.12-0.39%, and the balance of Al and inevitable impurities.

3. A method of producing an aluminum alloy material according to claim 1 or 2, characterized by: The RE is at least one selected from Sc, Er, La, Ce, Y and Yb.

4. The method of claim 1 or 2, wherein the aluminum alloy material is prepared by the steps of: The aluminum alloy material has an RP0.2≥70 MPa in the annealed state. ​ 5. Use of an aluminium alloy material produced by the production method according to any one of claims 1 to 4, characterized in that: The aluminum alloy material is used as a brazing material.

Images