A manufacturing process for a heat-resistant aluminum alloy

Abstract

This invention relates to the field of aluminum alloy technology, specifically to a manufacturing process for a heat-resistant aluminum alloy. The aluminum alloy comprises the following raw materials: copper, silicon, magnesium, zinc, manganese, nickel, titanium, lithium, aluminum, and a heat-resistant filler. Alumina-coated porous silicon carbide nanosheets are prepared as the heat-resistant filler and added during the aluminum alloy manufacturing process. The porous structure of the silicon carbide nanosheets allows for a snap-fit ​​bond with the alumina film, ensuring good stability of the alumina film and preventing easy detachment. The good compatibility between the alumina film and the aluminum alloy matrix ensures a tight bond between the prepared heat-resistant filler and the aluminum alloy matrix, resulting in uniform dispersion within the matrix. The unique sheet-like structure of the heat-resistant filler forms a uniform heat-insulating layer within the aluminum alloy matrix, thus giving the prepared aluminum alloy excellent heat resistance.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy technology, and more specifically to a manufacturing process for a heat-resistant aluminum alloy. Background Technology

[0002] Aluminum alloy is an alloy composed of pure aluminum as the base material and a certain amount of other metallic elements added. It is an alloy material with good castability, electrical conductivity, thermal conductivity, weldability, corrosion resistance, and ease of forming. With industrial development, aluminum alloy has gradually become a key new material for the casting industry and is widely used in aviation, aerospace, automotive, machinery manufacturing, shipbuilding, and other fields, such as aircraft skin, engine pistons, and cylinder liners. However, aluminum alloys manufactured with existing technology are prone to softening at high temperatures. Although composite materials of titanium alloys and carbon fiber can be used to replace aluminum alloys, the cost of titanium alloys and carbon fiber composite materials is too high. Therefore, in order to meet the high-temperature resistance requirements in aerospace, automotive, construction, rail transportation, and military industries, new manufacturing processes are needed to improve the heat resistance of aluminum alloys.

[0003] Patent application number 202010046160.5 discloses a manufacturing process for tensile heat-resistant aluminum alloy wires. First, carbon fiber and basalt fiber are dehydrated by adjusting tension. Then, the carbon fiber and basalt fiber are passed through a thermosetting resin composition in a constant-temperature adhesive bath to form a composite fiber reinforcing core. Finally, aluminum alloy monofilaments are stranded around the composite fiber reinforcing core, thus producing a tensile heat-resistant aluminum alloy wire. This invention utilizes the principle that thermosetting resin undergoes a chemical reaction under heating conditions, cross-linking and curing into an insoluble and infusible substance. This allows the carbon fiber and basalt fiber to be tightly bonded together. The stranding method then tightly bonds the aluminum alloy monofilaments to the composite fiber reinforcing core, producing a tensile heat-resistant aluminum alloy wire. Therefore, improving the bonding between inorganic materials and aluminum alloys is a key issue in the preparation of heat-resistant aluminum alloys. Summary of the Invention

[0004] The purpose of this invention is to provide a manufacturing process for heat-resistant aluminum alloys, which solves the following technical problems:

[0005] (1) It solves the problem of insufficient heat resistance of conventional aluminum alloys;

[0006] (2) The problem of insufficient bonding between heat-resistant filler and aluminum alloy was solved.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] A manufacturing process for a heat-resistant aluminum alloy, wherein the aluminum alloy comprises the following raw materials in parts by weight: 3-5 parts copper, 2-5 parts silicon, 4-7 parts magnesium, 0.5-2 parts zinc, 1-3 parts manganese, 1-2.5 parts nickel, 0.1-0.6 parts titanium, 0.1-0.5 parts lithium, 80-90 parts aluminum, and 5-10 parts heat-resistant filler;

[0009] The manufacturing process includes the following steps:

[0010] Step 1: High-temperature refining of raw materials

[0011] Copper, silicon, magnesium, zinc, manganese, nickel, titanium, and lithium are added to a smelting furnace, followed by aluminum. At high temperature, inert gas is blown in while stirring to remove air from the smelting furnace, so that only inert gas exists in the smelting furnace. Stirring for 8 to 10 hours yields an aluminum alloy solution.

[0012] Step 2: Forging heat-resistant aluminum alloy

[0013] First, pour the aluminum alloy solution from step one into the mold, then pour the heat-resistant filler into the mold, stir mechanically to mix evenly, let stand, and when the temperature drops to 300-500℃, perform atmospheric pressure forging to obtain the heat-resistant aluminum alloy.

[0014] The heat-resistant filler is an alumina-coated porous silicon carbide nanosheet.

[0015] Furthermore, in step one, the high temperature is 800–1000°C.

[0016] Furthermore, in step one, the inert gas is any one of neon, helium, or argon.

[0017] Furthermore, the preparation method of the heat-resistant filler is as follows:

[0018] Step A: Preparation of graphite nanosheets

[0019] Pour acetone and deionized water into a beaker, then add graphite powder. Under a pressure of 20-30 MPa, treat the solution using cavitation jet method for 2-3 hours to obtain a graphite nanosheet solution. After the solution has stood for 5-8 hours, filter it. Dry the solid obtained by filtration to obtain graphite nanosheets.

[0020] Step B: Preparation of porous silicon carbide nanosheets

[0021] Graphite nanosheets, silicon dioxide, and silicon were placed in a beaker, deionized water was added, and the mixture was stirred until homogeneous. The mixture was then milled using a sand mill. The resulting paste was dried in a drying oven and then transferred to a tube furnace. The paste was calcined at 1350–1500 °C for 2–3 hours and then cooled to room temperature. The paste was then soaked in a mixed acid solution for 12–16 hours, removed, washed, and dried. Finally, it was calcined in an inert gas atmosphere at 650–800 °C for 4–6 hours to obtain porous silicon carbide nanosheets.

[0022] Step C: Preparation of heat-resistant filler

[0023] Porous silicon carbide nanosheets, deionized water, and polyvinylpyrrolidone were sequentially poured into a beaker to prepare a suspension. The pH was adjusted, aluminum chloride was added and stirred until homogeneous. Ammonia was used to maintain pH stability. The mixture was heated and stirred at 45–60°C for 2–3 hours. The material was then filtered out, washed to remove impurities, and vacuum dried. After heat treatment at 500–600°C in air, a heat-resistant filler was obtained.

[0024] Further, in step A, the volume ratio of acetone to deionized water is 7 to 15:1.

[0025] Further, in step B, the mass ratio of the graphite nanosheets, silicon dioxide, and silicon is 15:22 to 25:14 to 20.

[0026] Further, in step B, the mixed acid solution is a mixture of hydrofluoric acid and dilute nitric acid with a volume ratio of 3 to 5:1.

[0027] Furthermore, in step C, the mass fraction of the ammonia water is 25-50%.

[0028] Furthermore, in step C, the pH value is 9 to 11.

[0029] Using the above technical solution, graphite is processed by cavitation jet method to obtain graphite nanosheets. Using graphite nanosheets as templates, they are first reacted with silicon under high temperature conditions to form silicon carbide nanosheets. The silicon carbide nanosheets are then etched with a mixed acid solution to generate a large number of pores in their structure, thus forming porous silicon carbide nanosheets. Then, aluminum hydroxide is deposited on the surface of the porous silicon carbide nanosheets using aluminum chloride as the aluminum source to form aluminum hydroxide-coated porous silicon carbide nanosheets. Finally, the aluminum hydroxide is calcined at high temperature to convert it into aluminum oxide, thus obtaining aluminum oxide-coated porous silicon carbide nanosheets, which are heat-resistant fillers.

[0030] The beneficial effects of this invention are:

[0031] This invention prepares porous silicon carbide nanosheets coated with alumina as a heat-resistant filler, which is then added during the manufacturing process of aluminum alloys to produce heat-resistant aluminum alloys. The porous structure of the silicon carbide nanosheets forms a snap-fit ​​bond with the alumina film, thus maintaining the stability of the alumina film and preventing it from easily detaching from the silicon carbide nanosheets. Utilizing the good compatibility between the alumina film and the aluminum alloy substrate, the prepared heat-resistant filler is tightly bonded to the aluminum alloy substrate and uniformly dispersed within it. The special sheet-like structure of the heat-resistant filler forms a uniform heat-insulating layer within the aluminum alloy substrate, thereby giving the prepared aluminum alloy excellent heat resistance.

[0032] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a SEM image of the porous silicon carbide nanosheets prepared in Example 1 of the present invention. Detailed Implementation

[0035] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1

[0037] A manufacturing process for a heat-resistant aluminum alloy includes the following steps:

[0038] Step 1: High-temperature refining of raw materials

[0039] Add 3g copper, 2g silicon, 4g magnesium, 0.5g zinc, 1g manganese, 1g nickel, 0.1g titanium, and 0.1g lithium together to a melting furnace, then add 80g aluminum. At a high temperature of 800℃, while stirring, blow argon gas to expel the air in the melting furnace so that only argon gas exists in the melting furnace. Stir for 10 hours to obtain an aluminum alloy solution.

[0040] Step 2: Forging heat-resistant aluminum alloy

[0041] First, pour the aluminum alloy solution from step one into the mold, then add 5g of heat-resistant filler into the mold. After mechanically stirring and mixing evenly, let it stand until the temperature drops to 300℃ and then perform atmospheric pressure forging to obtain the heat-resistant aluminum alloy.

[0042] The method for preparing the heat-resistant filler includes the following steps:

[0043] Step A: Preparation of graphite nanosheets

[0044] Pour 75ml of acetone and 25ml of deionized water into a beaker, then add 5g of graphite powder. Under a pressure of 20MPa, treat the solution using cavitation jet method for 2h to obtain a graphite nanosheet solution. After the solution has been left to stand for 5h, filter it. Dry the solid obtained by filtration to obtain graphite nanosheets.

[0045] Step B: Preparation of porous silicon carbide nanosheets

[0046] 1.5g of graphite nanosheets, 2.2g of silicon dioxide, and 1.4g of silicon were weighed and placed in a beaker. 50ml of deionized water was added and stirred until homogeneous. The mixture was then milled using a sand mill. The resulting paste was dried in a drying oven and then transferred to a tube furnace. It was calcined at 1350℃ for 2 hours. After cooling to room temperature, it was soaked in a mixed acid solution consisting of 12ml of 40% hydrofluoric acid and 3ml of 68% dilute nitric acid for 12 hours. The solution was then removed, washed, dried, and finally calcined at 650℃ for 4 hours under argon atmosphere to obtain porous silicon carbide nanosheets.

[0047] The porous silicon carbide nanosheets were scanned using a SEM5000 field emission scanning electron microscope. The results are shown in the figure. Figure 1 As can be seen from the figure, the porous silicon carbide nanosheets have a porous structure and are in sheet form.

[0048] Step C: Preparation of heat-resistant filler

[0049] 2g of porous silicon carbide nanosheets, 30ml of deionized water, and 1g of polyvinylpyrrolidone were sequentially poured into a beaker to prepare a suspension. The pH was adjusted to 11 with 25% ammonia water. 5g of aluminum chloride was added and stirred well. The ammonia water was continued to be used to maintain the pH at 11. After heating and stirring at 45℃ for 2 hours, the material was filtered out, washed to remove impurities, and vacuum dried. After heat treatment at 500℃ in air, the heat-resistant filler was obtained.

[0050] Example 2

[0051] A manufacturing process for a heat-resistant aluminum alloy includes the following steps:

[0052] Step 1: High-temperature refining of raw materials

[0053] Add 4g copper, 3g silicon, 5g magnesium, 1.5g zinc, 1.5g manganese, 1.5g nickel, 0.3g titanium, and 0.3g lithium to a melting furnace, then add 85g aluminum. At a high temperature of 900℃, while stirring, blow in argon gas to expel the air in the melting furnace, so that only argon gas exists in the melting furnace. Stir for 9 hours to obtain an aluminum alloy solution.

[0054] Step 2: Forging heat-resistant aluminum alloy

[0055] First, pour the aluminum alloy solution from step one into the mold, then pour 7g of heat-resistant filler into the mold, stir mechanically to mix evenly, let stand, and wait for the temperature to drop to 400℃ for atmospheric pressure forging to obtain heat-resistant aluminum alloy.

[0056] The preparation method of the heat-resistant filler is the same as that in Example 1.

[0057] Example 3

[0058] A manufacturing process for a heat-resistant aluminum alloy includes the following steps:

[0059] Step 1: High-temperature refining of raw materials

[0060] Add 5g copper, 5g silicon, 7g magnesium, 2g zinc, 3g manganese, 2.5g nickel, 0.6g titanium, and 0.5g lithium to a melting furnace, then add 90g aluminum. At a high temperature of 1000℃, while stirring, blow in argon gas to expel the air in the melting furnace, so that only argon gas exists in the melting furnace. Stir for 8 hours to obtain an aluminum alloy solution.

[0061] Step 2: Forging heat-resistant aluminum alloy

[0062] First, pour the aluminum alloy solution from step one into the mold, then pour 10g of heat-resistant filler into the mold, stir mechanically to mix evenly, let stand, and wait for the temperature to drop to 500℃ for atmospheric pressure forging to obtain heat-resistant aluminum alloy.

[0063] The preparation method of the heat-resistant filler is the same as that in Example 1.

[0064] Comparative Example 1

[0065] A manufacturing process for an aluminum alloy includes the following steps:

[0066] Step 1: High-temperature refining of raw materials

[0067] Add 4g copper, 3g silicon, 5g magnesium, 1.5g zinc, 1.5g manganese, 1.5g nickel, 0.3g titanium, and 0.3g lithium to a melting furnace, then add 85g aluminum. At a high temperature of 900℃, while stirring, blow in argon gas to expel the air in the melting furnace, so that only argon gas exists in the melting furnace. Stir for 9 hours to obtain an aluminum alloy solution.

[0068] Step 2: Forging aluminum alloy

[0069] First, pour the aluminum alloy solution from step one into a mold, then pour 7g of porous silicon carbide nanosheets into the mold. After mechanically stirring and mixing evenly, let it stand until the temperature drops to 400℃ and then perform atmospheric pressure forging to obtain the aluminum alloy.

[0070] The preparation method of the porous silicon carbide nanosheets is the same as that in Example 1.

[0071] Comparative Example 2

[0072] A manufacturing process for an aluminum alloy includes the following steps:

[0073] Add 4g of copper, 3g of silicon, 5g of magnesium, 1.5g of zinc, 1.5g of manganese, 1.5g of nickel, 0.3g of titanium, and 0.3g of lithium to a melting furnace, then add 85g of aluminum. At a high temperature of 900℃, while stirring, blow in argon gas to expel the air from the melting furnace, so that only argon gas exists in the melting furnace. Stir for 9 hours to obtain an aluminum alloy solution. Pour it into a mold, and after the temperature drops to 400℃, perform atmospheric pressure forging to obtain an aluminum alloy.

[0074] Performance testing:

[0075] The aluminum alloy products prepared in Examples 1-3 and Comparative Examples 1 and 2 of this invention were tested according to the requirements of GB / T3880-2006. The tensile strength test results at different temperatures are as follows:

[0076]

[0077] The data in the table show that the heat-resistant aluminum alloys prepared in Examples 1-3 of this invention exhibit low tensile strength variations and strong heat resistance at different temperatures. In contrast, Comparative Example 1 directly added porous silicon carbide nanosheets during the aluminum alloy manufacturing process, resulting in weak dispersion of the porous silicon carbide nanosheets in the aluminum alloy matrix, uneven heat insulation layer, and poor heat resistance. Comparative Example 2 did not add heat-resistant fillers during the aluminum alloy manufacturing process, leading to poor tensile strength and insufficient heat resistance at high temperatures.

[0078] The above description is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined in the claims, they should all fall within the protection scope of the present invention.

Claims

1. A manufacturing process for a heat-resistant aluminum alloy, characterized in that, The aluminum alloy comprises the following raw materials in parts by weight: 3-5 parts copper, 2-5 parts silicon, 4-7 parts magnesium, 0.5-2 parts zinc, 1-3 parts manganese, 1-2.5 parts nickel, 0.1-0.6 parts titanium, 0.1-0.5 parts lithium, 80-90 parts aluminum, and 5-10 parts heat-resistant filler. The manufacturing process includes the following steps: Step 1: High-temperature refining of raw materials Copper, silicon, magnesium, zinc, manganese, nickel, titanium, and lithium are added to a smelting furnace, followed by aluminum. At high temperature, inert gas is blown in while stirring to remove air from the smelting furnace, so that only inert gas exists in the smelting furnace. Stirring for 8 to 10 hours yields an aluminum alloy solution. Step 2: Forging heat-resistant aluminum alloy First, pour the aluminum alloy solution from step one into the mold, then pour the heat-resistant filler into the mold, stir mechanically to mix evenly, let stand, and when the temperature drops to 300-500℃, perform atmospheric pressure forging to obtain the heat-resistant aluminum alloy. The heat-resistant filler is an alumina-coated porous silicon carbide nanosheet; The preparation method of the heat-resistant filler is as follows: Step A: Preparation of graphite nanosheets Pour acetone and deionized water into a beaker, then add graphite powder. Under a pressure of 20-30 MPa, treat the solution using cavitation jet method for 2-3 hours to obtain a graphite nanosheet solution. After the solution has stood for 5-8 hours, filter it. Dry the solid obtained by filtration to obtain graphite nanosheets. Step B: Preparation of porous silicon carbide nanosheets Graphite nanosheets, silicon dioxide, and silicon were placed in a beaker, deionized water was added, and the mixture was stirred until homogeneous. The mixture was then milled using a sand mill. The resulting paste was dried in a drying oven and then transferred to a tube furnace. The paste was calcined at 1350–1500 °C for 2–3 hours and then cooled to room temperature. The paste was then soaked in a mixed acid solution for 12–16 hours, removed, washed, and dried. Finally, it was calcined in an inert gas atmosphere at 650–800 °C for 4–6 hours to obtain porous silicon carbide nanosheets. Step C: Preparation of heat-resistant filler Porous silicon carbide nanosheets, deionized water, and polyvinylpyrrolidone were sequentially poured into a beaker to prepare a suspension. The pH was adjusted, aluminum chloride was added and stirred until homogeneous. Ammonia was used to maintain pH stability. The mixture was heated and stirred at 45–60°C for 2–3 hours. The material was then filtered out, washed to remove impurities, and vacuum dried. After heat treatment at 500–600°C in air, a heat-resistant filler was obtained.

2. The manufacturing process of a heat-resistant aluminum alloy according to claim 1, characterized in that, In step one, the high temperature is 800-1000℃.

3. The manufacturing process of a heat-resistant aluminum alloy according to claim 1, characterized in that, In step one, the inert gas is any one of neon, helium, or argon.

4. The manufacturing process of a heat-resistant aluminum alloy according to claim 1, characterized in that, In step A, the volume ratio of acetone to deionized water is 7 to 15:

1.

5. The manufacturing process of a heat-resistant aluminum alloy according to claim 1, characterized in that, In step B, the mass ratio of the graphite nanosheets, silicon dioxide, and silicon is 15:22-25:14-20.

6. The manufacturing process of a heat-resistant aluminum alloy according to claim 1, characterized in that, In step B, the mixed acid solution is a mixture of hydrofluoric acid and dilute nitric acid with a volume ratio of 3 to 5:

1.

7. The manufacturing process of a heat-resistant aluminum alloy according to claim 1, characterized in that, In step C, the mass fraction of the ammonia water is 25-50%.

8. The manufacturing process of a heat-resistant aluminum alloy according to claim 1, characterized in that, In step C, the pH value is 9 to 11.

Images