Preparation method of reinforced aluminum-based composite material through vacuum reciprocating smelting assisted thin-strip cast rolling

Abstract

The invention belongs to the technical field of preparation of aluminum-based composite materials, and particularly relates to a preparation method of a reinforced aluminum-based composite material through vacuum reciprocating smelting assisted thin-strip cast rolling. Comprising the steps of aluminum matrix material preparation, ceramic / aluminum matrix composite powder vacuum ball milling, aluminum matrix and ceramic / aluminum matrix composite powder vacuum reciprocating smelting, thin strip cast rolling, cast strip primary treatment, cast strip heat treatment, hot rolling, cold rolling, performance optimization and the like. An aluminum alloy matrix bar with specific components is selected, ceramic particle / aluminum matrix composite powder with the mass fraction of 5%-25% is prepared through vacuum ball milling, it is ensured that aluminum powder is completely attached to the surfaces of ceramic particles, and good wetting of the particles and an aluminum matrix is achieved. And then thin strip cast rolling, heat treatment, hot rolling, cold rolling and other treatments are carried out. And finally, the ceramic / aluminum-based composite material with the ceramic particles uniformly distributed on the matrix is prepared, and the ceramic / aluminum-based composite material shows excellent tensile strength, elongation and wear resistance and has no grain boundary segregation phenomenon.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum-based composite material preparation, and specifically relates to a method for preparing a vacuum reciprocating smelting-assisted thin-strip casting and rolling-reinforced aluminum-based composite material. Background Art

[0002] In the field of materials science, the pursuit of lightweight, high-performance composite materials has become the key to promoting technological development and industrial applications. The performance of traditional single materials can no longer meet the complex and changing engineering needs. Aluminum-based composite materials, with their good mechanical properties, low density and excellent conductivity, have shown great potential in aerospace, vehicles, electronic packaging and national defense science and technology. Ceramic particle reinforced aluminum-based composites are a new type of composite material that adds ceramic particles to the aluminum matrix to improve the comprehensive properties of the material such as strength and wear resistance. However, traditional preparation processes such as stirring casting and powder metallurgy still have challenges in the uniform distribution of ceramic particles, interface bonding with the matrix and defect control. These problems not only affect the comprehensive performance of composite materials, but also limit their development in high-end application fields.

[0003] Thin strip casting and rolling technology is an efficient, short-process metal material preparation technology, which belongs to sub-rapid solidification. Applying thin strip casting and rolling technology to the preparation of ceramic / aluminum-based composite materials can make full use of its continuous production characteristics and improve production efficiency. At the same time, the sub-rapid solidification effect in the thin strip casting and rolling process helps to refine the microstructure of the material and improve the comprehensive performance of the material. Patent CN202311492267.2 discloses a method for preparing thin strips of aluminum-based composite materials by continuous casting and rolling, which is characterized by enhancing the continuous conveying and continuous infiltration of the preform, and realizing the continuous forming of aluminum-based composite material thin strips under the action of rapid cooling and casting and rolling force. The patent involves thin strip casting and rolling of aluminum-based composite materials, but does not mention vacuum reciprocating smelting and specific processing methods of ceramic particles, such as ball milling mixing and vacuum melting, so the comprehensive performance of the prepared aluminum-based composite materials cannot meet current needs. Summary of the invention

[0004] In view of the problems in the prior art, the present invention proposes a method for preparing aluminum-based composite materials reinforced by vacuum reciprocating melting assisted thin strip casting and rolling. The method combines the short process of thin strip casting and rolling technology with the precise controllability of vacuum reciprocating melting technology, and solves the problems of uneven distribution of ceramic particles in aluminum-based composite materials, poor wettability at the interface between the matrix and ceramic particles, and high porosity.

[0005] The technical solution of the present invention is: A method for preparing a vacuum reciprocating smelting assisted thin strip casting and rolling reinforced aluminum-based composite material comprises the following steps: Step (1), aluminum-based material preparation: an aluminum alloy matrix rod is configured according to a set composition, wherein the composition comprises, by weight percentage, the following: Mg 0.8-1.5%, Cu 0.15-4.9%, Si 0.4-0.8%, Mn 0.1-1.5%, Cr 0.04-0.35%, Zn 0.1-0.25%, Fe 0.35-0.7%, Ti 0.1-0.15%, N≤ 0.002%, O≤ 0.002%, and the balance is Al; the matrix material comprises one or more of 6xxx series aluminum alloy, 2xxx series aluminum alloy, and 7xxx aluminum alloy; Step (2), vacuum ball milling: vacuum ball milling the ceramic particles and the Al powder to ensure that the Al powder is completely attached to the surface of the ceramic particles, so that the ceramic particles and the aluminum powder are fully wetted, and a ceramic / aluminum-based composite powder with a mass fraction of 5-25% is prepared as a reinforcement phase; the ceramic particles provide a solidification heat transfer ratio of more than 30%; Step (3), vacuum melting: the aluminum alloy matrix rod prepared in step (1) is placed in a vacuum melting furnace, the ceramic / aluminum matrix composite powder prepared in step (2) is fed into the furnace through a powder feeding mechanism, and the vacuum is evacuated to 10 -3 Pa or less to remove impurities during the smelting process; the aluminum liquid temperature is raised to control the superheat at +25~65℃, and the bottom is set to blow argon to remove slag and degassing treatment; Step (4), reciprocating smelting: after the solution temperature reaches 680-720°C, mechanically stir for 30-60 minutes, then stand and cool for 20-30 minutes, and smelt in this way for 3-6 hours to remove gas and other impurities, ensure that the ceramic particles are evenly dispersed in the aluminum alloy melt, and form a good interface wetting and bonding with the matrix; Step (5), thin strip casting: start the casting and rolling machine and the water cooling system, and under the protection of the inert gas Ar or N2, inject the uniform ceramic particle / aluminum alloy composite melt obtained after the reciprocating smelting in step (4) into the lower water outlet of the flow bag, and enter the molten pool composed of two rotating casting rollers and two side sealing plates from top to bottom, thereby ensuring the smooth progress of the casting and rolling process and the stability of the cast strip quality; control the casting speed to 30-50 m / min, control the molten pool liquid level to 80-150 mm, and control the cast strip thickness to 3.0-15.0 mm; Step (6), preliminary treatment of the cast strip: the ceramic / aluminum-based composite material strip obtained in step (5) is cooled to room temperature, and then surface polished to control the roughness to be above Ra 2 μm, and then segmented using a wire cutting robot; Step (7), heat treatment of the cast strip: subjecting the ceramic / aluminum-based composite material strip treated in step (6) to a solid solution treatment at 450-550°C for 1-8 hours, followed by rapid cooling; an aging treatment temperature of 100-200°C for 6-24 hours; after the heat treatment, a ceramic / aluminum-based composite material strip having ceramic particles uniformly distributed in the matrix is ​​obtained; Step (8), hot rolling: hot rolling the ceramic / aluminum-based composite material strip after heat treatment, setting the hot rolling temperature to 550-580° C., which is higher than the recrystallization temperature and lower than the melting temperature to avoid cracking; through the hot rolling treatment, the grains are further refined, and the structure and performance of the composite material are significantly improved; Step (9), cold rolling: cold rolling is performed on the basis of hot rolling to obtain a ceramic / aluminum-based composite material plate with a thickness of 0.2-0.3 mm, and the surface quality is controlled between Ra 0.2 μm and Ra 1.6 μm; Furthermore, the above-mentioned method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, its preferred embodiment is that in step (1), 6xxx series aluminum alloys include 6063, 6061, 6005 aluminum alloys, 2xxx series aluminum alloys include 2017, 2024, 2219 aluminum alloys, and 7xxx aluminum alloys include 7075, 7050, 7005 aluminum alloys.

[0006] Furthermore, the above-mentioned method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material has a preferred embodiment that in step (2), the ceramic particles include SiC, TiC, and TiB2, wherein the particle size of the ceramic particles is less than 3 μm, the particle size of the Al powder is 30-50 μm, and the ball milling time is more than 30 hours.

[0007] Furthermore, in the above-mentioned method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, a preferred embodiment is that the solution temperature is controlled to be above 650°C during the reciprocating melting in step (4).

[0008] Furthermore, in the above-mentioned method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, a preferred embodiment is that the rapid cooling process after the solution treatment in step (7) includes water quenching, high-pressure water quenching, and liquid-gas atomized medium quenching to prevent adverse phase changes or structural evolution from occurring during the cooling process.

[0009] Furthermore, in the above-mentioned method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, a preferred embodiment is that after hot rolling in step (8), the mass fraction of ceramic reinforcing particles in the hot-rolled plate matrix of the ceramic / aluminum-based composite material is 10-50%, the ceramic particles are evenly distributed on the matrix, the size of the matrix ceramic particles is controlled to be 600-2000nm, there is no grain boundary segregation phenomenon, and there is no shrinkage cavity around the ceramic.

[0010] Furthermore, the above-mentioned method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material has a preferred embodiment that during the cold rolling treatment in step (9), the roll gap of the cold rolling mill is adjusted to 3.0~15.0mm, and the cold rolling direction is the same as the casting direction.

[0011] Furthermore, in the above-mentioned method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, its preferred embodiment is that after the cold rolling treatment in step (9), the size of the ceramic particles in the cold-rolled plate matrix is ​​controlled to be 600~2000nm, evenly distributed on the matrix, and there is no grain boundary segregation phenomenon; the tensile strength of the composite material is increased by 20%, the elongation reaches 5%~15%, the wear resistance is increased by more than 25%, and the microhardness is increased by more than 30%.

[0012] Furthermore, the above-mentioned method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, the preferred embodiment of which is that in step (3), in the vacuum melting chamber, the number of pores on the solidified cross section of the thin strip plate is ≤6 / 10mm 2 , and the pore size is ≤0.5μm. After hot rolling and cold rolling deformation in step (8) and step (9), all the pores are pressed together.

[0013] The design concept of the present invention is: The present invention combines vacuum reciprocating melting technology with thin strip casting and rolling technology to achieve uniform distribution of ceramic particles in the aluminum matrix, thereby significantly improving the comprehensive mechanical properties of ceramic / aluminum matrix composite materials. The design ideas of this method mainly include four aspects: The first is to use ceramic particles as the reinforcement phase, and through vacuum ball milling mixing technology, ensure that the ceramic particles are fully wetted and combined with the aluminum matrix, laying the foundation for subsequent smelting and casting and rolling; The second is reciprocating smelting in a vacuum environment, strictly controlling the vacuum degree and temperature in the smelting chamber to remove impurities during the smelting process, ensuring the uniform dispersion of ceramic particles in the aluminum alloy melt and forming a good interface wetting and bonding with the matrix. This step is crucial to improving the comprehensive mechanical properties of the composite material; The third is to accurately control the casting speed, molten pool level and casting strip thickness during the casting and rolling process to obtain high-quality composite material thin strips, and to perform preliminary processing and heat treatment on the casting strips to further regulate the internal structure and properties of the ceramic / aluminum-based composite materials; Fourthly, through hot rolling and cold rolling treatment, a ceramic / aluminum-based composite material plate with uniform distribution of ceramic particles, no grain boundary segregation and excellent mechanical properties is obtained.

[0014] This innovative method not only greatly expands the preparation scope of ceramic / aluminum-based composite materials, but also opens up a new perspective for the research and development of ceramic particle-reinforced aluminum-based composite materials, and has great application potential and industrial value. It can meet the stringent requirements of my country's aerospace, automobile lightweight and construction fields for the comprehensive performance of aluminum-based composite materials.

[0015] Advantages and beneficial effects of the present invention: 1. The present invention combines vacuum ball milling to mix ceramic particles / aluminum-based composite powders with vacuum reciprocating smelting technology to achieve thin strip casting and rolling in a vacuum environment of ≤3000Pa (≤0.03 bar), and the prepared ceramic / aluminum-based composite materials have excellent mechanical properties. Specifically, the tensile strength is increased by 20%, the elongation reaches 5-15% or higher, and the wear resistance is increased by more than 25%. The improvement of these properties is mainly due to the good combination and dispersed distribution of ceramic particles and aluminum matrix. Compared with traditional casting, powder metallurgy and other processes, the ceramic particles are wrapped by aluminum alloy powder, the wettability of the interface between ceramic particles and aluminum matrix is ​​enhanced, the strengthening effect is more uniform, and the solidification defects are significantly eliminated. A large number of aluminum-based composite material studies are basically based on preparation in non-vacuum environments, and often have a large number of pore-type defects, which is attributed to the poor wettability of ceramic particles and aluminum matrix causing gas phase retention. Vacuum ball milling mixing and vacuum reciprocating smelting technology can fundamentally solve this problem; 2. The preparation of ceramic particles / aluminum-based composite materials is generally carried out under normal pressure. This type of technology is generally deposited under normal pressure. The main problem is the agglomeration of ceramic particles and the existence of pores around them. At present, there is no research on the preparation of ceramic / aluminum-based composite materials by combining vacuum ball milling of ceramic particles / aluminum-based composite powders with vacuum reciprocating smelting technology to assist thin strip continuous casting. The ceramic / aluminum-based composite material of the present invention is smelted in a vacuum environment and is carried out under the protection of inert gas Ar gas, which effectively prevents oxidation and contamination of the aluminum-based composite material melt and improves the purity of the metal.

[0016] 3. In the process of vacuum reciprocating smelting, the present invention effectively prevents oxidation, removes gas and other impurities through strict temperature control and mechanical stirring time, and ensures that the ceramic particles are evenly dispersed in the aluminum melt. At the same time, the subsequent solution aging, hot rolling and cold rolling treatments can further press the pores, improve the density of the ceramic / aluminum-based composite material, and improve its comprehensive mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the process of vacuum reciprocating melting assisted thin strip casting and rolling ceramic particle reinforced aluminum-based composite material of the present invention; In the figure, 1-high vacuum pump group; 2-heating mechanism; 3-powder feeding mechanism; 4-stirring mechanism; 5-upper cover plate; 6-top rod; 7-crucible; 8-rotating casting roller; 9-air cooling device; 10-casting belt. DETAILED DESCRIPTION

[0018] The specific implementation methods of the present invention are further described in detail below in conjunction with the drawings and examples of the specification. The following examples are used to illustrate the present invention but cannot be used to limit the scope of the present invention. Those skilled in the art can make various deformations or modifications within the scope of the claims, which does not affect the essential content of the present invention.

[0019] The following embodiments adopt Figure 1 The process and device shown in the figure, wherein the high vacuum pump group 1 is responsible for providing a high vacuum environment for the system so that the smelting process is free of impurities; the heating mechanism 2 provides heat energy to make the aluminum-based composite material reach a molten state; the powder feeding mechanism 3 is responsible for feeding in ceramic particles; the stirring mechanism 4 promotes the full mixing of aluminum liquid and ceramic particles by stirring; the upper cover plate 5 closes the smelting area to prevent heat loss and external pollution; the ejector rod 6 is used to eject during pouring so that the aluminum-based composite solution flows out and enters the casting roller 8; the crucible 7 is a container for melting aluminum-based composite materials; the casting roller 8 makes the aluminum-based composite material into a thin strip through rapid cooling and rolling; the air cooling device 9 is used to cool the cast strip 10 to ensure the structure and performance of the thin strip; the cast strip 10 is a ceramic particle reinforced aluminum-based composite material thin strip finally prepared by vacuum reciprocating melting assisted thin strip casting and rolling, which has excellent mechanical properties. Example 1

[0020] The present embodiment provides a method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, comprising the following steps: (1) Preparation of 6063 aluminum matrix material: 6063 aluminum alloy bars are prepared according to the set composition, and the composition by weight percentage is: Mg 0.8%, Si 0.5%, Mn 0.6%, Cr 0.1%, Zn 0.15%, Fe 0.4%, Ti 0.1%, N ≤ 0.002%, O ≤ 0.002%, and the balance is Al; (2) Vacuum ball milling of SiC / 6063 composite powder: 5% SiC powder is used as a reinforcing material; SiC ceramic particles and Al powder are ball milled and mixed evenly for 30 hours to ensure that the Al powder is completely attached to the surface of the ceramic particles and that the ceramic particles and the aluminum liquid are fully wetted; the particle size of the ceramic particles is 3 μm, the particle size of the metal powder is 30 μm, and the proportion of solidification heat transfer provided by the particles is 30%; (3) Vacuum melting: Place the 6063 aluminum alloy rod and the ball-milled SiC / Al composite powder into a vacuum melting furnace and evacuate to 10 -5 Pa, to remove impurities during the smelting process; the aluminum liquid is heated to control the superheat to +25℃, and the bottom is set to blow argon to remove slag and degassing; the number of pores on the solidified cross section of the thin strip is 6 / 10mm 2 , and the pore size is 0.5μm; (4) Reciprocating smelting: After the solution temperature reaches 680°C, it is mechanically stirred for 30 minutes, then left to cool for 20 minutes, and reciprocated smelting is performed for 3 hours to remove impurities such as gas, ensure that the SiC ceramic particles are evenly dispersed in the aluminum alloy melt, and form good interface wetting and bonding with the matrix; (5) Strip casting: Start the casting and rolling mill and the water cooling system: inject the uniform SiC / 6063 aluminum-based composite melt obtained after vacuum reciprocating smelting into the lower water inlet of the casting roll, and enter the molten pool composed of two rotating casting rolls and the block side sealing plate from top to bottom. Control the casting speed to 30 m / min, the molten pool liquid level to 80 mm, and the cast strip thickness to 3.0 mm; (6) Preliminary treatment of the cast strip: The SiC / 6063 aluminum-based composite strip obtained by strip casting is cooled to room temperature, and then the surface is polished with the roughness controlled at Ra 2 μm, and then segmented by wire cutting; (7) Heat treatment of cast strip: solution treatment at 450 °C for 1 h, followed by rapid cooling by water quenching; aging treatment temperature at 100 °C for 6 h; after heat treatment, SiC / 6063 aluminum-based composite material with SiC particles evenly distributed in the matrix is ​​obtained; (8) Hot rolling: hot rolling of the heat-treated SiC / 6063 aluminum-based composite strip is performed at a temperature of 550 °C, which is higher than the recrystallization temperature and lower than the melting temperature to avoid cracking; through hot rolling treatment, the grains are further refined, and the microstructure and properties of the composite material are significantly improved; the mass fraction of ceramic reinforcing particles in the matrix of the ceramic / aluminum-based composite hot-rolled plate is 20%, the ceramic particles are evenly distributed on the matrix, and the size of the matrix ceramic particles is controlled at 800 nm; (9) Cold rolling: Cold rolling is performed on the basis of hot rolling. The roll gap of the cold rolling mill is adjusted to 5 mm. The cold rolling direction is the same as the casting direction. A 0.2 mm SiC / 6063 aluminum-based composite material plate is obtained. The surface quality is controlled between Ra 0.2 μm. After cold rolling, the ceramic particle size of the cold-rolled plate matrix is ​​controlled to be 600 nm.

[0021] The SiC / 6063 aluminum-based composite material finally prepared in this embodiment has SiC ceramic particles evenly distributed on the matrix without grain boundary segregation. The tensile strength of the composite material is increased by 20%, the elongation reaches 5%, the wear resistance is increased by 25%, and the microhardness is increased by 30%. Example 2

[0022] The present embodiment provides a method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, characterized by comprising the following steps: (1) Preparation of 2024 aluminum matrix material: Prepare 2024 aluminum alloy bars according to the set composition, which contains the following components by weight: Mg 1.2%, Si 0.4%, Mn 0.3%, Cr 0.04%, Zn0.15%, Fe 0.5%, Ti0.15%, N≤ 0.002%, O≤0.002%, and the balance is Al; (2) Vacuum ball milling of SiC / 2024 composite powder: 10% SiC powder is used as a reinforcing material; SiC ceramic particles and Al powder are ball milled and mixed evenly for 40 hours to ensure that the Al powder is completely attached to the surface of the ceramic particles and that the ceramic particles and the aluminum liquid are fully wetted; the particle size of the ceramic particles is 3 μm, the particle size of the metal powder is 30 μm, and the proportion of solidification heat transfer provided by the particles is 30%; (3) Vacuum melting: Place the 2024 aluminum alloy bar and the ball-milled SiC / Al composite powder into a vacuum melting furnace and evacuate to 10 -3 Pa, to remove impurities during the smelting process; the aluminum liquid is heated to control the superheat to +45℃, and the bottom is set to blow argon to remove slag and degassing; the number of pores on the solidified cross section of the thin strip is 6 / 10mm 2 , and the pore size is 0.5μm; (4) Reciprocating smelting: After the solution temperature reaches 700 °C, mechanical stirring is performed for 40 min, followed by cooling for 30 min, and reciprocating smelting is performed for 5 h to remove impurities such as gas, ensure that the SiC ceramic particles are evenly dispersed in the aluminum alloy melt, and form good interface wetting and bonding with the matrix; (5) Strip casting: Start the casting and rolling mill and the water cooling system: inject the uniform SiC / 2024 aluminum-based composite melt obtained after vacuum reciprocating smelting into the lower water inlet of the casting roll, and enter the molten pool composed of two rotating casting rolls and the block side sealing plate from top to bottom. Control the casting speed to 40 m / min, the molten pool liquid level to 120 mm, and the cast strip thickness to 4.0 mm; (6) Preliminary treatment of the cast strip: The SiC / 2024 aluminum-based composite material strip obtained by casting and rolling is cooled to room temperature, and then the surface is polished to control the roughness to be above Ra 2μm, and then segmented by wire cutting; (7) Cast strip heat treatment: solution treatment was performed at 500 °C for 5 h, followed by rapid cooling by water quenching; aging treatment temperature was 150 °C for 10 h; after heat treatment, a SiC / 2024 aluminum matrix composite material with SiC particles uniformly distributed in the matrix was obtained; (8) Hot rolling: The SiC / 2024 aluminum-based composite material strip after heat treatment is hot rolled, and the hot rolling temperature is set to 560°C, which is higher than the recrystallization temperature and lower than the melting temperature to avoid cracking. Through hot rolling treatment, the grains are further refined, and the structure and performance of the composite material are significantly improved. The mass fraction of ceramic reinforcing particles in the matrix of the ceramic / aluminum-based composite hot-rolled plate is 20%, and the ceramic particles are evenly distributed on the matrix. The size of the matrix ceramic particles is controlled at 1000nm. (9) Cold rolling: Cold rolling is performed on the basis of hot rolling. The roll gap of the cold rolling mill is adjusted to 10 mm. The cold rolling direction is the same as the casting direction. A 0.2 mm SiC / 2024 aluminum-based composite material plate is obtained. The surface quality is controlled between Ra 0.8 μm. After cold rolling, the ceramic particle size of the cold-rolled plate matrix is ​​controlled to be 800 nm.

[0023] The SiC / 2024 aluminum-based composite material finally prepared in this embodiment has SiC ceramic particles evenly distributed on the matrix without grain boundary segregation. The tensile strength of the composite material is increased by 20%, the elongation reaches 10%, the wear resistance is increased by 25%, and the microhardness is increased by 30%. Example 3

[0024] The present embodiment provides a method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, characterized by comprising the following steps: A method for preparing a vacuum reciprocating smelting assisted thin strip casting and rolling reinforced aluminum-based composite material comprises the following steps: (1) Preparation of 6061 aluminum matrix material: 6061 aluminum alloy bars are prepared according to the set composition, and the composition by weight percentage is: Mg 0.1%, Si 0.6%, Mn 0.7%, Cr 0.2%, Zn 0.15%, Fe 0.5%, Ti 0.12%, N ≤ 0.002%, O ≤ 0.002%; the balance is Al; (2) Vacuum ball milling of TiC / 6061 composite powder: 20% TiC powder is used as a reinforcing material; TiC ceramic particles and Al powder are ball milled and mixed evenly for 40 hours to ensure that the Al powder is completely attached to the surface of the ceramic particles and that the ceramic particles and the aluminum liquid are fully wetted; the particle size of the ceramic particles is 3 μm, the particle size of the metal powder is 40 μm, and the proportion of solidification heat transfer provided by the particles is 30%; (3) Vacuum melting: Place the 6061 aluminum alloy rod and the milled TiC / Al composite powder into a vacuum melting furnace and evacuate to 10 -3 Pa, to remove impurities during the smelting process; the aluminum liquid is heated to control the superheat to +65℃, and the bottom is set to blow argon to remove slag and degassing; the number of pores on the solidified cross section of the thin strip is 5 / 10mm 2 , and the pore size is 0.5μm; (4) Reciprocating smelting: After the solution temperature reaches 720°C, mechanical stirring is performed for 60 minutes, followed by cooling for 30 minutes, and reciprocating smelting is performed for 6 hours to remove impurities such as gas, ensure that the TiC ceramic particles are evenly dispersed in the aluminum alloy melt, and form good interface wetting and bonding with the matrix; (5) Strip casting: Start the casting and rolling mill and the water cooling system: inject the uniform TiC / 6061 aluminum-based composite melt obtained after vacuum reciprocating smelting into the lower water inlet of the casting roll, and enter the molten pool composed of two rotating casting rolls and the block side sealing plate from top to bottom. Control the casting speed to 50 m / min, the molten pool liquid level to 150 mm, and the cast strip thickness to 5.0 mm; (6) Preliminary treatment of the cast strip: The TiC / 6061 aluminum-based composite thin strip obtained by casting and rolling is cooled to room temperature, and then the surface is polished with the roughness controlled at Ra 2μm, and then segmented by wire cutting; (7) Cast strip heat treatment: solution treatment was carried out at 550 °C for 8 h, followed by rapid cooling by water quenching; aging treatment temperature was 200 °C for 24 h; after heat treatment, a TiC / 6061 aluminum matrix composite material with TiC particles uniformly distributed in the matrix was obtained; (8) Hot rolling: The heat-treated TiC / 6061 aluminum-based composite material strip is hot rolled, and the hot rolling temperature is set to 580°C, which is higher than the recrystallization temperature and lower than the melting temperature to avoid cracking. Through the hot rolling treatment, the grains are further refined, and the structure and performance of the composite material are significantly improved. The mass fraction of ceramic reinforcing particles in the matrix of the ceramic / aluminum-based composite hot-rolled plate is 50%, and the ceramic particles are evenly distributed on the matrix. The size of the matrix ceramic particles is controlled at 1500nm. (9) Cold rolling: Cold rolling is performed on the basis of hot rolling. The roll gap of the cold rolling mill is adjusted to 15.0 mm. The cold rolling direction is the same as the casting direction. A 0.3 mm thick TiC / 6061 aluminum-based composite material plate is obtained. The surface quality is controlled between Ra 1.6 μm. After cold rolling, the ceramic particle size of the cold-rolled plate matrix is ​​controlled to be 1000 nm.

[0025] The TiC / 6061 aluminum-based composite material finally prepared in this embodiment has TiC ceramic particles evenly distributed on the matrix without grain boundary segregation. The tensile strength of the composite material is increased by 20%, the elongation reaches 15%, the wear resistance is increased by 25%, and the microhardness is increased by 30%. Example 4

[0026] This embodiment is a method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material. The difference from Example 1 is that the matrix material used is 7075 aluminum alloy, and the composition is: Mg1.5%, Si 0.8%, Mn0.1%, Cr 0.18%, Zn0.25%, Fe 0.7%, Ti0.15%, N≤ 0.002%, O≤0.002%, and the balance is Al. 10% SiC powder is used as a reinforcing material, the particle size of the SiC powder particles is 2μm, and the particle size of the metal powder is 50μm. The SiC powder and the 7075 aluminum alloy powder are ball-milled and mixed and stirred evenly, the ball milling time is 35h, and the reciprocating melting time is 6h. Example 5

[0027] This embodiment is a method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material. The difference from Example 2 is that the matrix material used is 7075 aluminum alloy, and the composition is: Mg 1.5%, Si 0.3%, Mn0.1%, Cr 0.18%, Zn0.12%, Fe 0.7%, Ti0.1%, N≤ 0.002%, O≤0.002%, and the balance is Al; 25% SiC powder is used as a reinforcing material, and the particle size of the SiC powder particles is 2μm, and the metal powder is 40μm. The SiC powder and the 7075 aluminum alloy powder are ball-milled and mixed and stirred evenly, the ball milling time is 30h, and the ball milling speed is 300r / min; the reciprocating melting time is 3h. Example 6

[0028] This embodiment is a method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material. The difference from Example 3 is that the matrix material used is 6063 aluminum alloy. 25% TiC powder is used as a reinforcing material, the particle size of the TiC powder particles is 2μm, and the metal powder is 50μm. The TiC powder and the 6063 aluminum alloy powder are ball-milled and mixed and stirred evenly. The ball milling treatment is ball milling for 3h, pausing for 30min; ball milling for 2h, pausing for 20min; then repeating the operation mode of ball milling for 1h, pausing for 10min, and the ball milling time is 40h; the reciprocating melting time is 3h.

Claims

1. A method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material, characterized in that: The following steps are involved: Step (1), aluminum-based material preparation: an aluminum alloy matrix rod is configured according to a set composition, wherein the composition by weight percentage includes: Mg 0.8-1.8%, Si 0.4-0.8%, Cu 0.15-4.9%, Mn 0.1-1.5%, Cr 0.04-0.35%, Zn 0.1-0.25%, Fe 0.35-0.7%, Ti 0.1-0.15%, N≤ 0.002%, O≤ 0.002%, and the balance is Al; the matrix material includes one or more of 6xxx aluminum alloy, 2xxx aluminum alloy, and 7xxx aluminum alloy; Step (2), vacuum ball milling: vacuum ball milling the ceramic particles and the Al powder to ensure that the Al powder is completely attached to the surface of the ceramic particles, so that the ceramic particles and the aluminum powder are fully wetted, and a ceramic / aluminum-based composite powder with a mass fraction of 5-25% is prepared as a reinforcement phase; the ceramic particles provide a solidification heat transfer ratio of more than 30%; Step (3), vacuum melting: the aluminum alloy matrix rod prepared in step (1) is placed in a vacuum melting furnace, the ceramic / aluminum matrix composite powder prepared in step (2) is fed into the furnace through a powder feeding mechanism, and the vacuum is evacuated to 10 -3 Pa or less to remove impurities during the smelting process; the aluminum liquid temperature is raised to control the superheat at +25~65℃, and the bottom is set to blow argon to remove slag and degassing treatment; Step (4), reciprocating smelting: after the solution temperature reaches 680-720°C, mechanically stir for 30-60 minutes, then stand and cool for 20-30 minutes, and smelt in this way for 3-6 hours to remove impurities, ensure that the ceramic particles are evenly dispersed in the aluminum alloy melt, and form a good interface wetting and bonding with the matrix; Step (5), thin strip casting: start the casting and rolling mill and the water cooling system, and under the protection of inert gas Ar or N2, inject the uniform ceramic particle / aluminum alloy composite melt obtained after reciprocating smelting in step (4) into the lower water outlet of the flow bag, and enter the molten pool composed of two rotating casting rollers and two side sealing plates from top to bottom, control the casting speed to 30-50 m / min, control the molten pool liquid level to 80-150 mm, and control the thickness of the cast strip to 3.0-15.0 mm; Step (6), preliminary treatment of the cast strip: the ceramic / aluminum-based composite material strip obtained in step (5) is cooled to room temperature, and then surface polished to control the roughness to be above Ra 2 μm, and then segmented using a wire cutting robot; Step (7), heat treatment of the cast strip: subjecting the ceramic / aluminum-based composite material strip treated in step (6) to a solid solution treatment at 450-550°C for 1-8 hours, followed by rapid cooling; an aging treatment temperature of 100-200°C for 6-24 hours; after the heat treatment, a ceramic / aluminum-based composite material strip having ceramic particles uniformly distributed in the matrix is ​​obtained; Step (8), hot rolling: hot rolling the ceramic / aluminum-based composite material strip after heat treatment, setting the hot rolling temperature to 550-580° C., which is higher than the recrystallization temperature and lower than the melting temperature to avoid cracking; through the hot rolling treatment, the grains are further refined, and the structure and performance of the composite material are significantly improved; Step (9), cold rolling: cold rolling is performed on the basis of hot rolling to obtain a ceramic / aluminum-based composite material plate with a thickness of 0.2-0.3 mm, and the surface quality is controlled between Ra 0.2 μm and Ra 1.6 μm.

2. The method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material according to claim 1, characterized in that: In step (1), 6xxx series aluminum alloys include 6063, 6061, and 6005 aluminum alloys, 2xxx series aluminum alloys include 2017, 2024, and 2219 aluminum alloys, and 7xxx aluminum alloys include 7075, 7050, and 7005 aluminum alloys.

3. The method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material according to claim 1, characterized in that: In step (2), the ceramic particles include SiC, TiC, and TiB2, wherein the particle size of the ceramic particles is less than 3 μm, the particle size of the Al powder is 30-50 μm, and the ball milling time is more than 30 hours.

4. The method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material according to claim 1, characterized in that: In step (4), the solution temperature is controlled to be above 650° C. during reciprocating smelting.

5. The method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material according to claim 1, characterized in that: The rapid cooling process after the solution treatment in step (7) includes water quenching, high pressure water quenching, and liquid-gas atomized medium quenching to prevent adverse phase changes or structural evolution from occurring during the cooling process.

6. The method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material according to claim 1, characterized in that: After hot rolling in step (8), the mass fraction of ceramic reinforcement particles in the hot-rolled plate matrix of the ceramic / aluminum-based composite material is 10-50%, the ceramic particles are evenly distributed on the matrix, the size of the matrix ceramic particles is controlled to be 600-2000 nm, there is no grain boundary segregation phenomenon, and there is no shrinkage cavity around the ceramic.

7. The method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material according to claim 1, characterized in that: During the cold rolling process in step (9), the roll gap of the cold rolling mill is adjusted to 3.0-15.0 mm, and the cold rolling direction is the same as the casting direction.

8. The method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material according to claim 1, characterized in that: After the cold rolling treatment in step (9), the size of the ceramic particles in the cold-rolled plate matrix is ​​controlled to be 600-2000 nm, and the particles are evenly distributed on the matrix without grain boundary segregation. The tensile strength of the composite material is increased by 20%, the elongation is 5%-15%, the wear resistance is increased by more than 25%, and the microhardness is increased by more than 30%.

9. The method for preparing a vacuum reciprocating melting assisted thin strip casting and rolling reinforced aluminum-based composite material according to claim 1, characterized in that: In step (3), in the vacuum melting chamber, the number of pores on the solidified cross section of the thin strip is ≤ 6 / 10mm 2 , and the pore size is ≤0.5μm. After hot rolling and cold rolling deformation in step (8) and step (9), all the pores are pressed together.

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