Electromagnetic treatment reinforced high-performance cast aluminum alloy and manufacturing process thereof

Abstract

The application discloses an electromagnetic treatment reinforced high-performance cast aluminum alloy and a manufacturing process thereof, and relates to the technical field of cast aluminum alloys. Specifically, the application comprises the following steps: S1: mixing cerium dioxide powder and Ti6Al4V alloy powder through ball milling to obtain cladding material; S2: cleaning a cast aluminum alloy test piece to obtain a pretreated cast aluminum alloy test piece, wherein the cleaning comprises magnetron sputtering cleaning; S3: laser cladding the cladding material to the surface of the pretreated cast aluminum alloy test piece, and performing electromagnetic pulse treatment to obtain a clad cast aluminum alloy; and S4: performing low-temperature plasma nitriding treatment and low-frequency alternating magnetic field treatment on the clad cast aluminum alloy to obtain a high-performance cast aluminum alloy. Finally, under the synergistic effect of the process technologies of laser cladding, electromagnetic pulse treatment, low-temperature plasma nitriding treatment and low-frequency alternating magnetic field treatment, the high-performance cast aluminum alloy with close bonding and excellent mechanical properties is comprehensively prepared.

Description

Technical Field

[0001] This invention relates to the field of cast aluminum alloy technology, specifically to a high-performance cast aluminum alloy strengthened by electromagnetic treatment and its manufacturing process. Background Technology

[0002] Cast aluminum alloys possess advantages such as low density, high specific strength, and good formability, making them widely used in the aerospace field. However, cast aluminum alloys themselves have low hardness, poor wear resistance, and insufficient low-temperature impact toughness, making them prone to wear and impact failure during service. Therefore, the industry generally adopts surface strengthening processes to improve their surface mechanical properties. Currently, the mainstream strengthening processes mainly include anodizing, spraying, laser cladding, and ion nitriding, but each process has significant shortcomings: for example, the film formed by anodizing is thin and easily peels off; the coating layer formed by spraying has low bonding strength; the cladding layer formed by laser cladding also has low bonding strength; and ion nitriding directly forms the brittle AlN phase, which is extremely prone to cracking.

[0003] Based on this, the present invention provides a high-performance cast aluminum alloy strengthened by electromagnetic treatment and its manufacturing process, which is of great significance. Summary of the Invention

[0004] The purpose of this invention is to provide a high-performance cast aluminum alloy strengthened by electromagnetic treatment and its manufacturing process, so as to solve the problems mentioned in the background art.

[0005] To address the aforementioned technical problems, the first aspect of the present invention provides the following technical solution: A manufacturing process for electromagnetically strengthened high-performance cast aluminum alloy includes the following steps: S1: Cerium dioxide powder and Ti6Al4V alloy powder are ball-milled and mixed to obtain the cladding material; S2: Cleaning of cast aluminum alloy specimens to obtain pretreated cast aluminum alloy specimens; the cleaning process includes magnetron sputtering cleaning. S3: The cladding material is laser-clad onto the surface of the pretreated cast aluminum alloy specimen, followed by electromagnetic pulse treatment to obtain the coated cast aluminum alloy; S4: Low-temperature plasma nitriding treatment of coated cast aluminum alloy followed by low-frequency alternating magnetic field treatment yields a high-performance cast aluminum alloy.

[0006] Further, the cleaning process includes grinding, liquid cleaning, and magnetron sputtering cleaning in sequence; the specific process is as follows: (1) Grind the molded cast aluminum alloy specimen with sandpaper until the surface roughness Ra=1~3μm; (2) After grinding, use anhydrous ethanol and acetone to ultrasonically clean it for 5~15min in sequence, and then vacuum dry it; (3) After vacuum drying, perform magnetron sputtering cleaning on it to complete the cleaning.

[0007] Furthermore, the process parameters for the magnetron sputtering cleaning are as follows: under vacuum conditions, the vacuum degree is 1×10⁻⁶. -4 ~2×10 -4 Pa, working gas is argon, gas flow rate is 0.5~1L / min, working gas pressure is 0.5~1Pa, target distance is 50~100mm, sputtering power is 100~300W, sputtering bias voltage is -150~-300V, sputtering time is 5~15min.

[0008] Magnetron sputtering cleaning can effectively remove the oxide film layer on the surface of cast aluminum alloys, improving the adhesion between the oxide film and the subsequent cladding layer.

[0009] Furthermore, the process parameters for laser cladding are as follows: the substrate is preheated to 200~240℃, argon is used as the protective gas with a gas flow rate of 10~15L / min, the laser power is 2.8~3.3kW, the scanning speed is 300~500mm / min, the spot diameter is 2~3mm, the positive defocusing amount is 20~40mm, the powder feeding amount is 15~25g / min, and the thickness of the cladding layer is 0.2~1mm.

[0010] Furthermore, the cladding material is obtained by ball milling and mixing the following raw material components by mass fraction: 0.5~1wt% cerium dioxide powder, the remainder being Ti6Al4V alloy powder.

[0011] Furthermore, the process parameters for ball milling are as follows: argon is used as the protective gas, the gas pressure is 0.01~0.1MPa, the ball milling speed is 1000~2000rpm, the ball-to-material ratio is (8~10):1, and the particle size of the cladding material is 40~60μm after ball milling.

[0012] Furthermore, the process parameters for the electromagnetic pulse processing are as follows: magnetic induction intensity of 1.5~3T, frequency of 10~40Hz, duty cycle of 35~50%, processing time of 3~6min, and waveform of square wave.

[0013] Furthermore, the process parameters for the low-temperature plasma nitriding treatment are as follows: the working gas is a mixture of nitrogen and hydrogen, with a volume ratio of 1:(0.1~0.2), the gas flow rate is 0.5~1L / min, the nitriding bias voltage is -200~-400V, the nitriding temperature is 400~500℃, and the nitriding time is 3~6h.

[0014] Furthermore, the process parameters for the low-frequency alternating magnetic field treatment are: magnetic induction intensity of 0.4~0.8T, frequency of 15~25Hz, processing time of 15~25min, and waveform of sine wave.

[0015] Furthermore, during the low-frequency alternating magnetic field treatment, the alloy being treated is simultaneously assisted-heated to 160~220℃.

[0016] A second aspect of the present invention provides a high-performance cast aluminum alloy prepared by the above-described preparation method.

[0017] Compared with the prior art, the beneficial effects achieved by the present invention are: (1) The reason for using laser cladding for coating in this invention is as follows: This invention is designed to perform nitriding treatment on cast aluminum alloy specimens to improve their mechanical properties. However, considering that if the cast aluminum alloy specimens are directly nitrided, the resulting AlN will be too brittle, the nitriding interface will be prone to cracking, and the toughness of the cast aluminum alloy will also decrease rapidly. Undoubtedly, such cast aluminum alloys cannot meet the requirements of aerospace alloys. Therefore, this invention first uses laser cladding to clad a Ti6Al4V cladding layer on the initial cast aluminum alloy specimen, and uses this as a nitriding carrier to facilitate subsequent nitriding treatment. The raw materials of the Ti6Al4V cladding layer are mainly Ti6Al4V alloy powder and cerium dioxide powder. The Ti6Al4V alloy powder is a high titanium content alloy, and it also contains Al, which can ensure the bonding force between the alloy and the cast aluminum alloy specimen, and avoid the formation of TiAl3 due to excessive Al content, which would make the cladding layer too brittle and thus limit the performance of the specimen. The cerium dioxide powder can refine the grains and ensure the initial quality of the cladding layer.

[0018] (2) The purpose of electromagnetic treatment of the cast aluminum alloy specimen after laser cladding is that: there is residual stress inside the cladding layer, which can lead to peeling of the cladding layer and microcracks after nitriding, thus failing to effectively strengthen the specimen; therefore, electromagnetic treatment of the coated cast aluminum alloy is necessary to eliminate the internal residual stress. Considering the huge residual tensile stress inside the cladding layer after laser cladding and the need for instantaneous high-energy stress release, this invention designs and utilizes electromagnetic pulse treatment technology, and uses square waves to electromagnetically treat the cladding layer. By generating high-energy short pulses, the residual stress inside the cladding layer is quickly eliminated, thereby blocking the crack propagation channel in time and realizing the elimination of residual stress inside the coated cast aluminum alloy.

[0019] (3) The present invention further employs low-temperature plasma nitriding technology to nitrid the coated cast aluminum alloy. Due to the presence of the high titanium content Ti6Al4V cladding layer, nitriding can form TiN with better plasticity matching, thereby enhancing the mechanical properties of the cast aluminum alloy. The reason for using low-temperature plasma nitriding is that aluminum alloy has a low melting point, and this is to protect the dimensional accuracy of the cast aluminum alloy specimen.

[0020] (4) The purpose of electromagnetic treatment on the cast aluminum alloy specimen after nitriding is that, on the one hand, electromagnetic treatment can promote the uniform dispersion of nitrogen in the nitrided layer, thereby eliminating the quality difference in different parts of the nitrided layer; on the other hand, electromagnetic treatment can also eliminate the internal stress in the nitrided layer, thereby reducing the microscopic defects of the nitrided layer and improving the overall quality of the nitrided layer. The reason why the present invention uses low-frequency alternating magnetic field treatment technology after nitriding is that, after nitriding, a hard and brittle TiN phase is formed. If it is still treated with high-energy short pulses at this time, it will cause impact damage to the TiN phase. At the same time, high-energy short pulses cannot continuously drive the diffusion of nitrogen. Therefore, the present invention uses low-frequency alternating magnetic field treatment technology to treat the nitrided cast aluminum alloy, thereby optimizing the nitrided layer in a continuous and gentle manner, and thus preparing a high-performance cast aluminum alloy.

[0021] (5) In the process of low-frequency alternating magnetic field treatment, the nitrided coated aluminum alloy is further heated to 160~220℃, which can further promote the diffusion of nitrogen. Under the synergistic effect of the two, the defects of uneven nitriding distribution and large internal stress of nitrided layer caused by single low-temperature plasma nitriding are effectively compensated.

[0022] In summary, this invention mainly employs laser cladding, electromagnetic pulse treatment, low-temperature plasma nitriding, and low-frequency alternating magnetic field treatment to sequentially process the formed cast aluminum alloy specimens. The various processes complement each other and are closely integrated, ultimately resulting in a high-performance cast aluminum alloy with tight bonding and excellent mechanical properties. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0024] It should be noted that the following quantities are by weight. There are no special restrictions on the manufacturers of the raw materials involved in this invention. Exemplary examples include: 7055 aluminum alloy plate, cerium dioxide, and Ti6Al4V alloy powder, all of which are commercially available.

[0025] Preparatory work: (1) Cut the 7055 aluminum alloy plate into 200mm×200mm pieces, and heat it to 700℃ at 5℃ / min under argon protection. Stir for 5min while holding at the temperature. After removing the slag, test the content of each metal in the alloy and add Zn, Mg, Cu and Zr as appropriate to ensure that the mass fraction of Zn is 8.0±0.02%, the mass fraction of Mg is 2.3±0.02% and the mass fraction of Cu is 2.4±0.02%. The mass fraction of Zr is 0.13±0.02%; (2) After the addition is complete, continue stirring at 690℃ for 5 minutes, and then let stand for 10 minutes; (3) Then pour aluminum alloy liquid into the metal mold preheated to 200℃ at a uniform speed, about 10s / mold, keep the mold naturally cooled for 20 minutes, open the mold and take out the part, cut off the sprue and riser, and perform simple grinding to remove burrs and flash. Then keep it at 475℃ for 12 hours, furnace cool, and obtain cast aluminum alloy test piece.

[0026] Example 1: A manufacturing process for electromagnetically strengthened high-performance cast aluminum alloy: Step 1: Step 1-1: Cleaning: (1) Grind the molded cast aluminum alloy specimen with sandpaper until the surface roughness Ra=2.5±0.05μm; (2) After grinding, use anhydrous ethanol and acetone to ultrasonically clean it for 10min in sequence, and then dry it at 80℃ for 24h under a vacuum of 1Pa; (3) After vacuum drying, perform magnetron sputtering cleaning to complete the cleaning. The process parameters for magnetron sputtering cleaning are as follows: vacuum degree 1×10⁻⁶. -4 The sputtering parameters were: Pa, argon as the working gas, gas flow rate of 0.8 L / min, working gas pressure of 0.75 Pa, target-substrate distance of 75 mm, sputtering power of 200 W, sputtering bias of -250 V, and sputtering time of 10 min. Step 1-2: Coating: The cladding material is laser-clad onto the surface of the cleaned cast aluminum alloy specimen; The cladding material is obtained by ball milling and mixing the following raw material components by mass fraction: 0.8 wt% cerium dioxide powder, and the remainder is Ti6Al4V alloy powder; the specific ball milling process parameters are: argon as protective gas, gas pressure is 0.05 MPa, ball milling speed is 1500 rpm, ball-to-material ratio is 9:1, and the particle size of the cladding material is 50 ± 2 μm after ball milling. The process parameters for laser cladding are as follows: the substrate is preheated to 220℃, argon is used as the protective gas with a gas flow rate of 12.5L / min, the laser power is 3kW, the scanning speed is 400mm / min, the spot diameter is 2.5mm, the positive defocusing amount is 30mm, the powder feeding amount is 20g / min, and the thickness of the cladding layer is 0.5mm. Steps 1-3: Electromagnetic treatment: Electromagnetic pulse treatment is applied to the cast aluminum alloy of the laser cladding layer to obtain the coated cast aluminum alloy; The process parameters for electromagnetic pulse processing are as follows: magnetic induction intensity of 2.5T, frequency of 25Hz, duty cycle of 40%, processing time of 5min, and waveform of square wave. Step 2: Step 2-1: Nitriding treatment: Low-temperature plasma nitriding treatment is performed on the coated cast aluminum alloy; The process parameters for low-temperature plasma nitriding are as follows: a nitrogen / hydrogen mixture is used as the working gas with a volume ratio of 1:0.15, a gas flow rate of 0.8 L / min, a nitriding bias voltage of -300 V, a nitriding temperature of 450 °C, and a nitriding time of 4.5 h. Step 2-2: Electromagnetic treatment: The nitrided coated aluminum alloy is subjected to low-frequency alternating magnetic field treatment to obtain a high-performance aluminum alloy. The process parameters for the low-frequency alternating magnetic field treatment are: magnetic induction intensity of 0.6T, frequency of 20Hz, treatment time of 20min, and waveform of sine wave; during the low-frequency alternating magnetic field treatment, the nitrided coated aluminum alloy is assistedly heated to 180℃.

[0027] The following is a control experiment based on Example 1, with comparative examples 1 to 10, as detailed below: Comparative Example 1: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 1 is based on Example 1, with the following adjustment: magnetron sputtering cleaning is omitted, while other processes remain unchanged. Specifically: Step 1-1: Cleaning: (1) Use sandpaper to grind the molded cast aluminum alloy specimen to a surface roughness Ra=2.5±0.05μm; (2) After grinding, use anhydrous ethanol and acetone to ultrasonically clean it for 10min in sequence, and then dry it at 80℃ for 24h under a vacuum of 1Pa to complete the cleaning.

[0028] Comparative Example 2: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 2 is based on Example 1, with the following adjustments: all Ti6Al4V alloy powder in the laser cladding material was replaced with pure titanium powder, while other processes remained unchanged. Specifically: Step 1-2: Coating: The cladding material is laser-clad onto the surface of the cleaned cast aluminum alloy specimen; The cladding material is obtained by ball milling and mixing the following raw material components by mass fraction: 0.8 wt% cerium dioxide powder, and the remainder is pure titanium powder; the specific ball milling process parameters are: argon as protective gas, gas pressure is 0.05 MPa, ball milling speed is 1500 rpm, ball-to-material ratio is 9:1, and the particle size of the cladding material is 50 ± 2 μm after ball milling. The process parameters for laser cladding are as follows: the substrate is preheated to 220℃, argon is used as the protective gas with a gas flow rate of 12.5L / min, the laser power is 3kW, the scanning speed is 400mm / min, the spot diameter is 2.5mm, the positive defocusing amount is 30mm, the powder feeding amount is 20g / min, and the thickness of the cladding layer is 0.5mm.

[0029] Comparative Example 3: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 3 is based on Example 1, with the following adjustment: cerium dioxide powder is not added to the cladding material used in the laser cladding, while other processes remain unchanged. Specifically: Step 1-2: Coating: The cladding material is laser-clad onto the surface of the cleaned cast aluminum alloy specimen; The cladding material is Ti6Al4V alloy powder ball-milled to a particle size of 50±2μm; the specific ball milling process parameters are: argon as the protective gas, gas pressure of 0.05MPa, ball milling speed of 1500rpm, and ball-to-material ratio of 9:1. The process parameters for laser cladding are as follows: the substrate is preheated to 220℃, argon is used as the protective gas with a gas flow rate of 12.5L / min, the laser power is 3kW, the scanning speed is 400mm / min, the spot diameter is 2.5mm, the positive defocusing amount is 30mm, the powder feeding amount is 20g / min, and the thickness of the cladding layer is 0.5mm.

[0030] Comparative Example 4: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 4 is based on Example 1, with the following adjustment: after laser cladding, electromagnetic pulse treatment is not performed, while other processes remain unchanged. Specifically: Step 1: Step 1-1: Cleaning: (1) Grind the molded cast aluminum alloy specimen with sandpaper until the surface roughness Ra=2.5±0.05μm; (2) After grinding, use anhydrous ethanol and acetone to ultrasonically clean it for 10min in sequence, and then dry it at 80℃ for 24h under a vacuum of 1Pa; (3) After vacuum drying, perform magnetron sputtering cleaning to complete the cleaning. The process parameters for magnetron sputtering cleaning are as follows: vacuum degree 1×10⁻⁶. -4The sputtering parameters were: Pa, argon as the working gas, gas flow rate of 0.8 L / min, working gas pressure of 0.75 Pa, target-substrate distance of 75 mm, sputtering power of 200 W, sputtering bias of -250 V, and sputtering time of 10 min. Step 1-2: Coating: The cladding material is laser-clad onto the surface of the cleaned cast aluminum alloy specimen to obtain a coated cast aluminum alloy; The cladding material is obtained by ball milling and mixing the following raw material components by mass fraction: 0.8 wt% cerium dioxide powder, and the remainder is Ti6Al4V alloy powder; the specific ball milling process parameters are: argon as protective gas, gas pressure is 0.05 MPa, ball milling speed is 1500 rpm, ball-to-material ratio is 9:1, and the particle size of the cladding material is 50 ± 2 μm after ball milling. The process parameters for laser cladding are as follows: the substrate is preheated to 220℃, argon is used as the protective gas with a gas flow rate of 12.5L / min, the laser power is 3kW, the scanning speed is 400mm / min, the spot diameter is 2.5mm, the positive defocusing amount is 30mm, the powder feeding amount is 20g / min, and the thickness of the cladding layer is 0.5mm.

[0031] Comparative Example 5: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 5 is based on Example 1, with the following adjustment: after low-temperature plasma nitriding treatment, low-frequency alternating magnetic field treatment is not performed, while other processes remain unchanged. Specifically: Step 2: Step 2-1: Nitriding treatment: The coated cast aluminum alloy is subjected to low-temperature plasma nitriding treatment to obtain a high-performance cast aluminum alloy. The process parameters for low-temperature plasma nitriding are as follows: a nitrogen / hydrogen mixture is used as the working gas with a volume ratio of 1:0.15, a gas flow rate of 0.8 L / min, a nitriding bias voltage of -300 V, a nitriding temperature of 450 °C, and a nitriding time of 4.5 h.

[0032] Comparative Example 6: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 6 is based on Example 1, with the following adjustment: the laser cladding and electromagnetic pulse treatment in step 1 are omitted, while other processes remain unchanged. Specifically: Step 1: Step 1-1: Cleaning: (1) Grind the molded cast aluminum alloy specimen with sandpaper until the surface roughness Ra=2.5±0.05μm; (2) After grinding, use anhydrous ethanol and acetone to ultrasonically clean it for 10min in sequence, and then dry it at 80℃ for 24h under a vacuum of 1Pa; (3) After vacuum drying, perform magnetron sputtering cleaning to complete the cleaning. The process parameters for magnetron sputtering cleaning are as follows: vacuum degree 1×10⁻⁶. -4 The sputtering parameters were: Pa, argon as the working gas, gas flow rate of 0.8 L / min, working gas pressure of 0.75 Pa, target-substrate distance of 75 mm, sputtering power of 200 W, sputtering bias of -250 V, and sputtering time of 10 min. Step 1-2: Nitriding treatment: Low-temperature plasma nitriding treatment is performed on the coated cast aluminum alloy; The process parameters for low-temperature plasma nitriding are as follows: a nitrogen / hydrogen mixture is used as the working gas with a volume ratio of 1:0.15, a gas flow rate of 0.8 L / min, a nitriding bias voltage of -300 V, a nitriding temperature of 450 °C, and a nitriding time of 4.5 h. Steps 1-3: Electromagnetic treatment: The nitrided coated aluminum alloy is subjected to low-frequency alternating magnetic field treatment to obtain a high-performance aluminum alloy. The process parameters for the low-frequency alternating magnetic field treatment are: magnetic induction intensity of 0.6T, frequency of 20Hz, treatment time of 20min, and waveform of sine wave; during the low-frequency alternating magnetic field treatment, the nitrided coated aluminum alloy is assistedly heated to 180℃.

[0033] Comparative Example 7: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 7 is based on Example 1, with the following adjustments: the low-temperature plasma nitriding treatment and low-frequency alternating magnetic field treatment in step 2 are omitted, while other processes remain unchanged. Specifically: Step 1: Step 1-1: Cleaning: (1) Grind the molded cast aluminum alloy specimen with sandpaper until the surface roughness Ra=2.5±0.05μm; (2) After grinding, use anhydrous ethanol and acetone to ultrasonically clean it for 10min in sequence, and then dry it at 80℃ for 24h under a vacuum of 1Pa; (3) After vacuum drying, perform magnetron sputtering cleaning to complete the cleaning. The process parameters for magnetron sputtering cleaning are as follows: vacuum degree 1×10⁻⁶. -4 The sputtering parameters were: Pa, argon as the working gas, gas flow rate of 0.8 L / min, working gas pressure of 0.75 Pa, target-substrate distance of 75 mm, sputtering power of 200 W, sputtering bias of -250 V, and sputtering time of 10 min. Step 1-2: Coating: The cladding material is laser-clad onto the surface of the cleaned cast aluminum alloy specimen; The cladding material is obtained by ball milling and mixing the following raw material components by mass fraction: 0.8 wt% cerium dioxide powder, and the remainder is Ti6Al4V alloy powder; the specific ball milling process parameters are: argon as protective gas, gas pressure is 0.05 MPa, ball milling speed is 1500 rpm, ball-to-material ratio is 9:1, and the particle size of the cladding material is 50 ± 2 μm after ball milling. The process parameters for laser cladding are as follows: the substrate is preheated to 220℃, argon is used as the protective gas with a gas flow rate of 12.5L / min, the laser power is 3kW, the scanning speed is 400mm / min, the spot diameter is 2.5mm, the positive defocusing amount is 30mm, the powder feeding amount is 20g / min, and the thickness of the cladding layer is 0.5mm. Steps 1-3: Electromagnetic treatment: Electromagnetic pulse treatment is applied to the cast aluminum alloy of the laser cladding layer to obtain the coated cast aluminum alloy; The process parameters for electromagnetic pulse processing are as follows: magnetic induction intensity of 2.5T, frequency of 25Hz, duty cycle of 40%, processing time of 5min, and waveform of square wave.

[0034] Comparative Example 8: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 8 is based on Example 1, with the following adjustments: The electromagnetic treatment in step 1 also uses a low-frequency alternating magnetic field, the relevant parameters remain unchanged, and other processes also remain unchanged. Specifically: Step 1: Step 1-1: Cleaning: (1) Grind the molded cast aluminum alloy specimen with sandpaper until the surface roughness Ra=2.5±0.05μm; (2) After grinding, use anhydrous ethanol and acetone to ultrasonically clean it for 10min in sequence, and then dry it at 80℃ for 24h under a vacuum of 1Pa; (3) After vacuum drying, perform magnetron sputtering cleaning to complete the cleaning. The process parameters for magnetron sputtering cleaning are as follows: vacuum degree 1×10⁻⁶. -4 The sputtering parameters were: Pa, argon as the working gas, gas flow rate of 0.8 L / min, working gas pressure of 0.75 Pa, target-substrate distance of 75 mm, sputtering power of 200 W, sputtering bias of -250 V, and sputtering time of 10 min. Step 1-2: Coating: The cladding material is laser-clad onto the surface of the cleaned cast aluminum alloy specimen; The cladding material is obtained by ball milling and mixing the following raw material components by mass fraction: 0.8 wt% cerium dioxide powder, and the remainder is Ti6Al4V alloy powder; the specific ball milling process parameters are: argon as protective gas, gas pressure is 0.05 MPa, ball milling speed is 1500 rpm, ball-to-material ratio is 9:1, and the particle size of the cladding material is 50 ± 2 μm after ball milling. The process parameters for laser cladding are as follows: the substrate is preheated to 220℃, argon is used as the protective gas with a gas flow rate of 12.5L / min, the laser power is 3kW, the scanning speed is 400mm / min, the spot diameter is 2.5mm, the positive defocusing amount is 30mm, the powder feeding amount is 20g / min, and the thickness of the cladding layer is 0.5mm. Steps 1-3: Electromagnetic treatment: The cast aluminum alloy of the laser cladding layer is subjected to low-frequency alternating magnetic field treatment to obtain the clad cast aluminum alloy; The process parameters for the low-frequency alternating magnetic field treatment are: magnetic induction intensity of 2.5T, frequency of 25Hz, treatment time of 5min, and waveform of sine wave.

[0035] Comparative Example 9: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 9 is based on Example 1, with the following adjustments: In step 2, the electromagnetic treatment also uses electromagnetic pulse treatment, the relevant parameters remain unchanged, and other processes also remain unchanged. Specifically: Step 2: Step 2-1: Nitriding treatment: Low-temperature plasma nitriding treatment is performed on the coated cast aluminum alloy; The process parameters for low-temperature plasma nitriding are as follows: a nitrogen / hydrogen mixture is used as the working gas with a volume ratio of 1:0.15, a gas flow rate of 0.8 L / min, a nitriding bias voltage of -300 V, a nitriding temperature of 450 °C, and a nitriding time of 4.5 h. Step 2-2: Electromagnetic treatment: The nitrided coated aluminum alloy is subjected to electromagnetic pulse treatment to obtain a high-performance aluminum alloy. The process parameters for electromagnetic pulse treatment are as follows: magnetic induction intensity is 0.6T, frequency is 20Hz, duty cycle is 40%, processing time is 20min, and waveform is square wave; during electromagnetic pulse treatment, the coated cast aluminum alloy is assistedly heated to 180℃.

[0036] Comparative Example 10: A manufacturing process for an electromagnetically strengthened high-performance cast aluminum alloy: Comparative Example 10 is based on Example 1, with the following adjustment: auxiliary heating of the nitrided coated aluminum alloy is not performed in step 2, while other processes remain unchanged. Specifically: Step 2: Step 2-1: Nitriding treatment: Low-temperature plasma nitriding treatment is performed on the coated cast aluminum alloy; The process parameters for low-temperature plasma nitriding are as follows: a nitrogen / hydrogen mixture is used as the working gas with a volume ratio of 1:0.15, a gas flow rate of 0.8 L / min, a nitriding bias voltage of -300 V, a nitriding temperature of 450 °C, and a nitriding time of 4.5 h. Step 2-2: Electromagnetic treatment: The nitrided coated aluminum alloy is subjected to low-frequency alternating magnetic field treatment to obtain a high-performance aluminum alloy. The process parameters for the low-frequency alternating magnetic field treatment are: magnetic induction intensity of 0.6T, frequency of 20Hz, treatment time of 20min, and waveform of sine wave.

[0037] Performance testing: Interface bonding and mechanical property tests were conducted on the high-performance cast aluminum alloys manufactured in Example 1 and Comparative Examples 1-10. The specific test methods are as follows: 1. Interface bonding test: (1) Wipe the surface of the high-performance cast aluminum alloy twice with anhydrous ethanol. Then, use a special knife to make 10 cuts evenly in the horizontal and vertical directions on the sample surface. The depth of the cuts should reach the substrate and the interval between the cuts should be 2 mm to form a square grid. (3) Use a soft brush to gently brush away the powder generated by the grid. Then, apply 3M600 tape tightly to the square grid area and press it firmly to remove the air between the tape and the surface of the cast aluminum alloy as much as possible. (4) Quickly tear off the 3M600 tape in the opposite direction at 180° and observe the peeling of the coating on the grid and the edge of the cut on the sample.

[0038] 2. Mechanical property test: (1) The hardness was tested by Rockwell hardness tester and the average value of the three test results was taken; (2) The impact toughness at room temperature and -40℃ was tested according to GB / T 229-2020 as the experimental standard. V-notch specimens were used, the initial energy was 300J, and the pendulum blade radius was 2mm.

[0039] The specific test results are shown in Table 1 below: Table 1

[0040] Results Analysis: As can be seen from the data in Table 1 above, the present invention uses laser cladding, electromagnetic pulse treatment, low-temperature plasma nitriding treatment, and low-frequency alternating magnetic field treatment to process the formed cast aluminum alloy specimens in sequence. Each process complements and is closely combined, and finally a high-performance cast aluminum alloy with tight bonding and excellent mechanical properties is obtained.

[0041] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A manufacturing process for electromagnetically strengthened high-performance cast aluminum alloy, characterized in that: Includes the following steps: S1: Cerium dioxide powder and Ti6Al4V alloy powder are ball-milled and mixed to obtain the cladding material; S2: Cleaning of cast aluminum alloy specimens to obtain pretreated cast aluminum alloy specimens; the cleaning includes magnetron sputtering cleaning. S3: The cladding material is laser-clad onto the surface of the pretreated cast aluminum alloy specimen, followed by electromagnetic pulse treatment to obtain the coated cast aluminum alloy; S4: Low-temperature plasma nitriding treatment of coated cast aluminum alloy followed by low-frequency alternating magnetic field treatment yields a high-performance cast aluminum alloy.

2. The manufacturing process of an electromagnetically treated and strengthened high-performance cast aluminum alloy according to claim 1, characterized in that: The process parameters for the electromagnetic pulse processing are: magnetic induction intensity of 1.5~3T, frequency of 10~40Hz, duty cycle of 35~50%, processing time of 3~6min, and waveform of square wave; The process parameters for the low-frequency alternating magnetic field treatment are: magnetic induction intensity of 0.4~0.8T, frequency of 15~25Hz, processing time of 15~25min, and waveform of sine wave.

3. The manufacturing process of an electromagnetically treated and strengthened high-performance cast aluminum alloy according to claim 1, characterized in that: The cladding material is obtained by ball milling and mixing the following raw material components by mass fraction: 0.5~1wt% cerium dioxide powder, the remainder being Ti6Al4V alloy powder; The process parameters for ball milling are as follows: argon is used as the protective gas, the gas pressure is 0.01~0.1MPa, the ball milling speed is 1000~2000rpm, the ball-to-material ratio is (8~10):1, and the particle size of the cladding material is 40~60μm after ball milling.

4. The manufacturing process of an electromagnetically treated and strengthened high-performance cast aluminum alloy according to claim 1, characterized in that: The process parameters for the magnetron sputtering cleaning are as follows: under vacuum conditions, the vacuum level is 1×10⁻⁶. -4 ~2×10 -4 The sputtering process is as follows: using argon as the working gas, the gas flow rate is 0.5~1L / min, the working gas pressure is 0.5~1Pa, the target-substrate distance is 50~100mm, the sputtering power is 100~300W, the sputtering bias voltage is -150~-300V, and the sputtering time is 5~15min.

5. The manufacturing process of an electromagnetically treated and strengthened high-performance cast aluminum alloy according to claim 1, characterized in that: The process parameters for laser cladding are as follows: the substrate is preheated to 200~240℃, argon is used as the protective gas with a gas flow rate of 10~15L / min, the laser power is 2.8~3.3kW, the scanning speed is 300~500mm / min, the spot diameter is 2~3mm, the positive defocusing amount is 20~40mm, the powder feeding amount is 15~25g / min, and the thickness of the cladding layer is 0.2~1mm.

6. The manufacturing process of an electromagnetically treated and strengthened high-performance cast aluminum alloy according to claim 1, characterized in that: The process parameters for the low-temperature plasma nitriding treatment are as follows: a nitrogen / hydrogen mixture is used as the working gas, with a volume ratio of 1:(0.1~0.2), a gas flow rate of 0.5~1L / min, a nitriding bias voltage of -200~-400V, a nitriding temperature of 400~500℃, and a nitriding time of 3~6h.

7. The manufacturing process of an electromagnetically treated and strengthened high-performance cast aluminum alloy according to claim 1, characterized in that: During the low-frequency alternating magnetic field treatment, the alloy being treated is simultaneously assisted-heated to 160~220℃.

8. A high-performance cast aluminum alloy, characterized in that: It is manufactured by any one of the manufacturing processes described in claims 1 to 7.

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