A high-strength aluminum alloy collecting pipe

Abstract

The present invention relates to the field of manifold technology, and specifically to a high-strength aluminum alloy manifold, which produces a synergistic strengthening effect through the interface bonding between different layers of materials. The silicon aluminum alloy of the corrosion-resistant layer and the aluminum alloy of the buffer layer combine to form a new strengthening phase at the interface, further improving the overall strength and toughness of the manifold, exceeding the original design expectations. In addition, although there are requirements for the purity of the raw materials, trace impurities may cause unexpected chemical reactions during the complex smelting and processing process. When preparing the aluminum alloy of the reinforcement layer, extremely small amounts of other impurity elements interact with additives such as zirconium and vanadium to generate new compounds, which unexpectedly improve the thermal stability of the alloy and can still maintain good mechanical properties in high-temperature environments. The design of the four-layer composite structure and the reinforcement ribs and reinforcement rings may make the stress distribution more uniform than theoretical expectations when subjected to complex stresses, and has broad application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of current collecting pipes, and in particular to a high-strength aluminum alloy current collecting pipe. Background Art

[0002] As a key component widely used in industry and daily life, manifolds play an indispensable role in numerous fields. In the field of air conditioning and refrigeration, manifolds are responsible for collecting and distributing refrigerant, ensuring smooth circulation within the system. Their performance directly influences the operating efficiency, cooling and heating effects, and stability of the air conditioning system. For example, in large commercial central air conditioning systems, manifolds are required to evenly distribute refrigerant to each evaporator coil to achieve efficient heat exchange and meet the temperature regulation needs of large spaces.

[0003] In the automotive industry, manifolds are used in automotive air conditioning systems and engine cooling systems. During driving, the temperature inside the engine compartment fluctuates dramatically, and operating conditions are complex, placing extremely high demands on the strength and reliability of manifolds. Manifolds in automotive air conditioning systems must operate stably under harsh conditions such as vibration and alternating high and low temperatures to ensure the proper functioning of the air conditioning system and provide a comfortable environment for drivers and passengers. Manifolds in engine cooling systems must withstand the pressure shock of high-temperature coolant to maintain the engine's normal operating temperature and prevent overheating and damage.

[0004] In the aerospace industry, manifolds are used in aircraft fuel, hydraulic, and environmental control systems. Aerospace environments place extremely stringent demands on equipment reliability and lightweighting. Manifolds must not only possess sufficient strength to withstand high pressure, high vibration, and extreme temperature fluctuations, but also be as lightweight as possible to reduce the overall weight of the aircraft, improving flight performance and fuel efficiency. For example, if a manifold in an aircraft's fuel system exhibits strength issues and results in fuel leakage, it poses a serious threat to flight safety.

[0005] Currently, aluminum alloys are a common material for manifolds due to a combination of factors, including cost, weight, and corrosion resistance. However, existing aluminum alloy manifolds have significant strength limitations. In actual use, especially under complex and variable operating conditions such as frequent pressure fluctuations, rapid temperature changes, and intense mechanical vibration, manifolds must withstand the impact of high-pressure fluids. Insufficient strength can cause pipeline leaks, leading to the release of flammable and explosive media. This can not only cause significant economic losses but also lead to serious safety incidents, threatening personnel safety and the surrounding environment.

[0006] In building heating and hot water supply systems, manifolds are exposed to high-temperature, high-pressure water environments for long periods of time. Insufficient strength will significantly shorten the service life of the manifolds. Frequent repairs and replacements not only increase maintenance costs, but also affect the normal use of the building.

[0007] Therefore, according to the above-mentioned related technologies, it is urgent to develop a high-strength aluminum alloy header. Summary of the Invention

[0008] In view of this, the purpose of the present invention is to propose a high-strength aluminum alloy header to meet the growing performance requirements in various fields, improve the reliability and stability of the system, and reduce operating risks and maintenance costs.

[0009] Based on the above objectives, the present invention provides a high-strength aluminum alloy header.

[0010] A high-strength aluminum alloy manifold, the manifold having a four-layer composite structure, the four-layer composite structure comprising, from the inside to the outside, a corrosion-resistant layer, a buffer layer, a reinforcement layer, and a wear-resistant layer;

[0011] The thickness ratio of the corrosion-resistant layer, buffer layer, reinforcement layer and wear-resistant layer is 1.5-2mm: 1-1.5mm: 1.5-2mm: 0.8-1.2mm;

[0012] A nano coating is deposited on the outer surface of the wear-resistant layer;

[0013] The material of the corrosion-resistant layer is silicon-aluminum alloy;

[0014] The material of the buffer layer is aluminum alloy;

[0015] The material of the reinforcement layer is high-strength aluminum alloy;

[0016] The material of the wear-resistant layer is a high-hardness aluminum alloy;

[0017] The nano coating is an aluminum alloy composite material reinforced by carbon nanotubes.

[0018] Preferably, the preparation process of the silicon-aluminum alloy in the corrosion-resistant layer is as follows:

[0019] Step A1. Place an aluminum ingot in a melting furnace and smelt it at 720-750°C until the aluminum ingot is completely melted into a liquid state. Add industrial pure silicon and stir at 100-150 rpm for 20-25 minutes. Then add additive 1 and stir at 120-150 rpm for 15-20 minutes to obtain a mixed solution 1.

[0020] Step A2. The mixed gas 1 is introduced into the mixed liquid 1 and refined at a speed of 100-120 rpm for 20-30 min. After the refining is completed, the mixture is allowed to stand for 7-10 min to obtain a refined liquid 1. The refined liquid 1 is cast into a mold preheated to 200-250°C for casting. During the casting process, the casting speed is controlled at 3-5 kg / s. After the casting is completed, the mold is cooled at a cooling rate of 10-15°C / s. After the alloy is completely solidified, it is removed from the mold to obtain a preliminarily formed silicon-aluminum alloy billet 1;

[0021] Step A3. The silicon-aluminum alloy billet 1 is hot rolled, the billet is heated to 450-500°C, and rolled on a hot rolling mill with 3-5 rolling passes and a reduction of 10%-15% for each rolling. After hot rolling, the billet is cold rolled with 2-3 cold rolling passes and a reduction of 5%-8% for each cold rolling. The cold-rolled silicon-aluminum alloy is cut, stamped, and processed to form a corrosion-resistant layer that meets the size specifications.

[0022] Preferably, the purity of the aluminum ingot in step A1 is ≥99.5%;

[0023] The mass ratio of the aluminum ingot, industrial pure silicon and additive 1 in step A1 is 85-92:6-12:0.6-2.8;

[0024] The additive 1 in step A1 is a mixture of magnesium and manganese in a mass ratio of 0.5-2:0.1-0.8;

[0025] The mixed gas 1 in step A2 is obtained by mixing argon and chlorine in a volume ratio of 5:1;

[0026] The flow rate of the mixed gas 1 in step A2 is controlled to be 0.5-1 L / min.

[0027] Preferably, the preparation process of the aluminum alloy in the buffer layer is as follows:

[0028] Step B1. Place the aluminum ingot in a resistance melting furnace and heat it to 680-720°C to completely melt it into a liquid state. Add industrial pure magnesium and stir at 120-180 rpm for 20-30 minutes. Add additive 2 and flux 1 and stir at 120-180 rpm for 15-20 minutes to obtain mixed solution 2.

[0029] Step B2. The mixed gas 2 is introduced into the mixed liquid 2 and refined at a speed of 100-150 rpm for 25-35 min. After the refining is completed, the mixture is allowed to stand for 8-12 min to obtain a refined liquid 2. The refined liquid 2 is cast into a mold preheated to 230-280°C at a casting speed of 4-6 kg / s. The mold is cooled at a cooling rate of 8-12°C / s to obtain an aluminum alloy billet 2;

[0030] Step B3. Forging the aluminum alloy billet 2, heating the billet to 480-530° C., forging it 3-5 times on a forging device, controlling the forging ratio at 3-5, and forming a buffer layer that meets the specifications after forging.

[0031] Preferably, the purity of the aluminum ingot in step B1 is ≥99.8%;

[0032] The purity of the industrial pure magnesium in step B1 is ≥99.5%;

[0033] The mass ratio of the aluminum ingot, industrial pure magnesium, additive 2 and flux 1 in step B1 is 90-95:3-6:0.1-0.5:0.3-1;

[0034] The additive 2 in step B1 is obtained by mixing titanium and boron in a mass ratio of 0.05-0.3:0.05-0.2;

[0035] The flux 1 in step B1 is a mixture of potassium chloride and sodium chloride in a mass ratio of 1-1.2:1.5-3;

[0036] The mixed gas 2 in step B2 is obtained by mixing argon and chlorine in a volume ratio of 6:1;

[0037] The gas flow rate of the mixed gas 2 in step B2 is 0.6-1.2 L / min.

[0038] Preferably, the preparation process of the high-strength aluminum alloy in the reinforcement layer is as follows:

[0039] Step C1. Place the aluminum ingot in an electromagnetic induction melting furnace and heat it to 730-760°C to completely melt it into a liquid state. Then, add industrial pure copper and industrial pure magnesium, stir at a stirring frequency of 150-200 Hz for 30-40 minutes, then add additive 3, and continue stirring at a stirring frequency of 150-200 Hz for 25-30 minutes to obtain a mixed solution 3.

[0040] Step C2. Mixed gas 3 is introduced into the mixed solution 3, and the mixture is refined at a stirring frequency of 150-200 Hz for 30-40 minutes. Then, flux 2 is added, stirring is continued for 10-15 minutes, and then the mixture is allowed to stand for 10-15 minutes. Then, a sodium salt modifier is added, stirring is continued at a stirring frequency of 150-200 Hz for 10-12 minutes, and then the mixture is kept warm for 5-10 minutes to obtain an aluminum alloy billet 3;

[0041] Step C3. Cast the aluminum alloy billet 3 into a mold preheated to 250-300°C at a casting rate of 5-7 kg / s. Cool the mold at a cooling rate of 12-18°C / s. After the alloy is completely solidified, remove it from the mold, heat the removed billet to 500-550°C, and roll it on a hot rolling mill 3-5 times. The total rolling deformation is controlled at 60%-80%. After hot rolling, heat it to 530-550°C and keep it for 2-3 hours. Water-cooled quenching is performed, and the quenched alloy is then heated to 150-180°C and kept warm for 6-8 hours. Finally, the aluminum alloy is machined according to the design size of the collector to obtain a reinforcement layer.

[0042] Preferably, the purity of the aluminum ingot in step C1 is ≥99.9%;

[0043] The purity of the industrial pure copper in step C1 is ≥99.6%;

[0044] The purity of the industrial pure magnesium in step C1 is ≥99.5%;

[0045] The mass ratio of the aluminum ingot, industrial pure copper, industrial pure magnesium, additive 3, flux 2 and sodium salt modifier is 80-90:4-8:2-5:0.1-0.5:0.5-1:0.1-0.3;

[0046] The additive 3 is a mixture of zirconium and vanadium in a mass ratio of 0.05-0.3:0.05-0.2;

[0047] The flux 2 is a mixture of potassium chloride and sodium chloride in a mass ratio of 0.1-0.2:0.4-0.8;

[0048] The mixed gas 3 in step C2 is obtained by mixing argon and chlorine in a volume ratio of 8:1;

[0049] The gas flow rate of the mixed gas 3 in step C2 is 0.8-1.5 L / min.

[0050] Preferably, the preparation process of the high hardness aluminum alloy in the wear-resistant layer is as follows:

[0051] Step D1. Place the aluminum ingot in an electromagnetic induction melting furnace and heat it to 750-780°C to completely melt it into a liquid state. Argon gas is introduced into the furnace, and silicon carbide particles are added. Stir at a stirring frequency of 200-250 Hz for 40-50 minutes. Then, industrial pure copper and additive 4 are added, and stirring is continued for 20-25 minutes to obtain a mixed solution 4.

[0052] Step D2. Adding mixed gas 4 to the mixed solution 4 and refining for 35-50 minutes, then adding flux 3, stirring evenly, and letting it stand for 12-18 minutes. Then, adding a sodium salt modifier, stirring evenly, and holding the mixture for 6-10 minutes to obtain refined solution 4. The refined solution 4 is cast into a mold preheated to 280-320°C at a casting speed of 6-8 kg / s. After casting, the mold is cooled at a cooling rate of 15-20°C / s to obtain alloy billet 4;

[0053] Step D3. Heat the alloy billet 4 to 520-560°C, extrude it on a hot extruder with an extrusion ratio controlled at 10-15, then heat the alloy to 540-560°C and keep it warm for 2.5-3.5 hours, then quench it in cold water, heat the quenched alloy to 160-190°C and keep it warm for 7-9 hours, and finally machine the alloy according to the size of the collector to obtain a wear-resistant layer.

[0054] Preferably, the mass ratio of the aluminum ingot, silicon carbide particles, industrial pure copper, additive 4, flux 3 and sodium salt modifier is 70-85:10-20:3-8:0.1-1:0.6-1.2:0.15-0.35;

[0055] The purity of the aluminum ingot in step D1 is ≥99.9%;

[0056] The purity of the silicon carbide particles in step D1 is ≥99.7%;

[0057] The purity of the pure copper in step D1 is ≥99.5%;

[0058] The additive 4 in step D1 is a mixture of yttrium and boron in a mass ratio of 0.05-0.5:0.05-0.5;

[0059] In step D2, the flux 3 is potassium chloride, sodium chloride and calcium fluoride in a mass ratio of 25-40:40-60:5-15;

[0060] The mixed gas 4 in step D2 is obtained by mixing argon and chlorine in a volume ratio of 10:1;

[0061] The gas flow rate of the mixed gas 4 in step D2 is 1-1.8 L / min.

[0062] Preferably, the preparation process of the nano coating is as follows:

[0063] Step E1. Add sodium phosphate, sodium hydroxide and sodium silicate to deionized water and stir to obtain an electrolyte;

[0064] Step E2. Immerse the surface of the wear-resistant layer of the header in a sodium hydroxide solution at a temperature of 60-80°C and a concentration of 50-80g / L for 10-15min, and then soak in a nitric acid solution at a temperature of 40-60°C and a concentration of 30-50g / L for 5-10min;

[0065] Step E3. Place the treated wear-resistant layer of the collector into an electrolytic cell filled with electrolyte, use a stainless steel plate as the cathode, and conduct electricity at a voltage of 250-350V at a current of 8-12A / dm 2 The plasma electrolytic oxidation treatment is carried out at a current density of 1000 nm and 20-30°C for 50-70 minutes to form an oxide film with a thickness of 20-30 μm;

[0066] Step E4. The carbon nanotubes were placed in a mixed acid solution and ultrasonically treated at 60-80°C for 2-3 hours. The carbon nanotubes were then repeatedly rinsed with deionized water until neutral and vacuum dried at 80-100°C for 2-3 hours. The manifold was fixed on the sample stage in the reactor, and the distance between the sample stage and the gas nozzle was adjusted to 10-15 cm. The manifold was placed in the reactor and argon was introduced as a carrier gas. The reactor was then heated to 500-600°C and the mixed gas 5 was introduced. The deposition time was 2-3 hours at 10-20 Pa to obtain a nanocoating with a thickness of 3-5 μm.

[0067] The mass ratio of sodium phosphate, sodium hydroxide, sodium silicate and deionized water in step E1 is 5-10:3-7:5-10:73-87;

[0068] The mixed acid solution in step E4 is obtained by mixing concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:3;

[0069] The flow rate of argon gas in step E4 is controlled at 50-100 mL / min;

[0070] In step E4, the concentration of carbon nanotubes in the mixed gas 5 is 0.1-0.3 g / L, and the concentration of the aluminum alloy precursor is 1-3 mol / L;

[0071] The mass ratio of trimethylaluminum, tetraethylsilane and magnesium acetylacetonate in the aluminum alloy precursor is 40-50:30-40:10-20.

[0072] Preferably, the preparation process of the aluminum alloy header is as follows:

[0073] The corrosion-resistant layer, buffer layer, reinforcement layer and wear-resistant layer are processed by milling technology to form main reinforcement ribs with mesh distribution, oblique auxiliary reinforcement ribs and reinforcement rings. The height of the main reinforcement ribs is 1-1.5mm and the width is 0.5-0.8mm. The main reinforcement ribs run through the buffer layer, reinforcement layer and wear-resistant layer from the corrosion-resistant layer in sequence to enhance the overall compression and deformation resistance of the collector. The height of the auxiliary reinforcement ribs is 0.8-1.2mm and the width is 0.4-0.6mm, which are used to improve the torsion and bending resistance of the collector. The thickness of the reinforcement ring is 1-1.5mm and is set at the key position to further enhance the local strength of the collector. These reinforcement structures not only connect the corrosion-resistant The functions of the corrosion-resistant layer, buffer layer, reinforcement layer and wear-resistant layer can also effectively improve the overall mechanical properties of the collecting pipe. At the connection part of the collecting pipe, a plug-in connection structure is made by combining machining and assembly. First, the connecting pipe, sealing rubber ring groove and locking nut groove are made by machining, and then the sealing rubber ring and locking nut are installed, and finally the reinforcing bushing is inserted. This structure can not only ensure the sealing of the connection part, but also improve the compression and tensile strength of the connection part, and ensure the reliability of the collecting pipe during use. After the corrosion-resistant layer, buffer layer, reinforcement layer and wear-resistant layer are synthesized into the collecting pipe, the wear-resistant layer on the surface of the collecting pipe is surface treated to obtain a nano coating, and then the aluminum alloy collecting pipe is obtained.

[0074] Beneficial effects of the present invention:

[0075] The present invention provides a high-strength aluminum alloy manifold that produces a synergistic strengthening effect through the interface bonding between different layers of material. The silicon-aluminum alloy of the corrosion-resistant layer combines with the aluminum alloy of the buffer layer to form a new strengthening phase at the interface, further enhancing the overall strength and toughness of the manifold, exceeding the original design expectations. Furthermore, despite requirements for raw material purity, trace impurities can cause unexpected chemical reactions during the complex smelting and processing processes. For example, during the preparation of the aluminum alloy for the strengthening layer, extremely small amounts of other impurity elements interact with additives such as zirconium and vanadium to form new compounds, unexpectedly improving the alloy's thermal stability and maintaining good mechanical properties even in high-temperature environments.

[0076] The four-layer composite structure, along with the ribs and rings, can achieve more uniform stress distribution than theoretically expected when subjected to complex stresses. For example, under severe vibration conditions found in aerospace, the synergistic effect of the ribs and rings effectively disperses stress within the manifold, reducing the risk of rupture caused by localized stress concentration and significantly improving its reliability. After plasma electrolytic oxidation treatment and nanocoating deposition, the manifold surface may unexpectedly acquire certain self-healing properties. When the surface is slightly abraded, the carbon nanotube and aluminum alloy composite material in the nanocoating may undergo microstructural changes, filling the tiny defects caused by wear and extending the manifold's service life, promising broad application prospects. DETAILED DESCRIPTION

[0077] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0078] Example 1: A method for preparing a corrosion-resistant layer of a high-strength aluminum alloy collector, comprising the following steps:

[0079] S1. Mixing magnesium and manganese to obtain an additive 1, wherein the mass ratio of magnesium to manganese is 0.5:0.1;

[0080] S2. An aluminum ingot with a purity of ≥99.5% was placed in a melting furnace and smelted at 720°C until the aluminum ingot was completely melted into a liquid state. Industrial pure silicon was added and stirred at a speed of 100 rpm for 20 minutes. Additive 1 was then added and stirred at a speed of 120 rpm for 15 minutes to obtain a mixed solution 1, wherein the mass ratio of the aluminum ingot, industrial pure silicon and additive 1 was 85:6:0.6;

[0081] S3. Argon and chlorine were mixed in a volume ratio of 5:1 to obtain a mixed gas 1;

[0082] S4. The mixed gas 1 was introduced into the mixture 1, the flow rate of the mixed gas 1 was controlled to 0.5 L / min, and the mixture was refined at a speed of 100 rpm for 20 min. After the refining was completed, it was allowed to stand for 7 min to obtain a refined liquid 1, and the refined liquid 1 was cast into a mold preheated to 200 ℃ for casting. During the casting process, the casting speed was controlled to 3 kg / s. After the casting was completed, the mold was cooled and the cooling rate was controlled to 10 ℃ / s. After the alloy was completely solidified, it was removed from the mold to obtain a preliminarily formed silicon-aluminum alloy billet 1;

[0083] S5. The silicon-aluminum alloy billet 1 is hot rolled by heating the billet to 450°C and rolling it on a hot rolling mill with three rolling passes and a reduction of 10% for each rolling. After hot rolling, the billet is cold rolled with two cold rolling passes and a reduction of 5%-6-7-8% for each cold rolling. The cold-rolled silicon-aluminum alloy is cut, stamped, and processed to produce a corrosion-resistant layer that meets the size specifications.

[0084] Example 2: A method for preparing a corrosion-resistant layer of a high-strength aluminum alloy collector, comprising the following steps:

[0085] S1. Mixing magnesium and manganese to obtain an additive 1, wherein the mass ratio of magnesium to manganese is 1:0.3;

[0086] S2. An aluminum ingot with a purity of ≥99.5% was placed in a melting furnace and smelted at 730°C until the aluminum ingot was completely melted into a liquid state. Industrial pure silicon was added and stirred at 120 rpm for 22 min. Additive 1 was then added and stirred at 130 rpm for 17 min to obtain a mixed solution 1, wherein the mass ratio of the aluminum ingot, industrial pure silicon, and additive 1 was 88:8:1.2;

[0087] S3. Argon and chlorine were mixed in a volume ratio of 5:1 to obtain a mixed gas 1;

[0088] S4. A mixed gas mixture was introduced into the mixture 1, the flow rate of the mixed gas 1 was controlled to 0.7 L / min, and the mixture was refined at a speed of 105 rpm for 23 min. After the refining was completed, the mixture was allowed to stand for 8 min to obtain a refined liquid 1, which was cast into a mold preheated to 220 ° C for casting. During the casting process, the casting speed was controlled to 3.5 kg / s. After the casting was completed, the mold was cooled at a cooling rate of 12 ° C / s. After the alloy was completely solidified, it was removed from the mold to obtain a preliminarily formed silicon-aluminum alloy billet 1;

[0089] S5. The silicon-aluminum alloy billet 1 is hot rolled by heating the billet to 470°C and rolling it on a hot rolling mill with four rolling passes and a reduction of 12% for each rolling. After hot rolling, the billet is cold rolled with three cold rolling passes and a reduction of 6% for each cold rolling. The cold-rolled silicon-aluminum alloy is cut, stamped, and processed to produce a corrosion-resistant layer that meets the size specifications.

[0090] Example 3: A method for preparing a corrosion-resistant layer of a high-strength aluminum alloy header, comprising the following steps:

[0091] S1. Mixing magnesium and manganese to obtain an additive 1, wherein the mass ratio of magnesium to manganese is 1.5:0.5;

[0092] S2. An aluminum ingot with a purity of ≥99.5% was placed in a melting furnace and smelted at 740°C until the aluminum ingot was completely melted into a liquid state. Industrial pure silicon was added and stirred at 130 rpm for 24 min. Additive 1 was then added and stirred at 140 rpm for 18 min to obtain a mixed solution 1, wherein the mass ratio of the aluminum ingot, industrial pure silicon, and additive 1 was 90:10:2.3;

[0093] S3. Argon and chlorine were mixed in a volume ratio of 5:1 to obtain a mixed gas 1;

[0094] S4. A mixed gas mixture was introduced into the mixture 1, the flow rate of the mixed gas 1 was controlled to 0.9 L / min, and the mixture was refined at a speed of 110 rpm for 26 min. After the refining was completed, the mixture was allowed to stand for 9 min to obtain a refined liquid 1, which was cast into a mold preheated to 240 ° C for casting. During the casting process, the casting speed was controlled to 4 kg / s. After the casting was completed, the mold was cooled and the cooling rate was controlled to 14 ° C / s. After the alloy was completely solidified, it was removed from the mold to obtain a preliminarily formed silicon-aluminum alloy billet 1;

[0095] S5. The silicon-aluminum alloy billet 1 is hot rolled by heating the billet to 480°C and rolling it on a hot rolling mill with three rolling passes and a reduction of 14% for each rolling. After hot rolling, the billet is cold rolled with two cold rolling passes and a reduction of 7% for each cold rolling. The cold-rolled silicon-aluminum alloy is cut, stamped, and processed to produce a corrosion-resistant layer that meets the size specifications.

[0096] Example 4: A method for preparing a corrosion-resistant layer of a high-strength aluminum alloy header, comprising the following steps:

[0097] S1. Mixing magnesium and manganese to obtain an additive 1, wherein the mass ratio of magnesium to manganese is 2:0.8;

[0098] S2. An aluminum ingot with a purity of ≥99.5% was placed in a melting furnace and smelted at 750°C until the aluminum ingot was completely melted into a liquid state. Industrial pure silicon was added and stirred at 150 rpm for 25 min. Additive 1 was then added and stirred at 150 rpm for 20 min to obtain a mixed solution 1, wherein the mass ratio of the aluminum ingot, industrial pure silicon, and additive 1 was 92:12:2.8;

[0099] S3. Argon and chlorine were mixed in a volume ratio of 5:1 to obtain a mixed gas 1;

[0100] S4. A mixed gas mixture was introduced into the mixture 1, the flow rate of the mixed gas 1 was controlled to 1 L / min, and the mixture was refined at a speed of 120 rpm for 30 min. After the refining was completed, the mixture was allowed to stand for 10 min to obtain a refined liquid 1, which was cast into a mold preheated to 250 ° C for casting. During the casting process, the casting speed was controlled to 5 kg / s. After the casting was completed, the mold was cooled and the cooling rate was controlled to 15 ° C / s. After the alloy was completely solidified, it was removed from the mold to obtain a preliminarily formed silicon-aluminum alloy billet 1;

[0101] S5. The silicon-aluminum alloy billet 1 is hot rolled by heating the billet to 500°C and rolling it on a hot rolling mill with 5 rolling passes and a reduction of 15% for each rolling. After hot rolling, the billet is cold rolled with 3 cold rolling passes and a reduction of 8% for each cold rolling. The cold-rolled silicon-aluminum alloy is cut, stamped, and processed to produce a corrosion-resistant layer that meets the size specifications.

[0102] Example 5: A method for preparing a buffer layer of a high-strength aluminum alloy current collector, comprising the following steps:

[0103] S1. Titanium and boron were mixed in a mass ratio of 0.05:0.05 to obtain additive 2;

[0104] S2. Potassium chloride and sodium chloride were mixed in a mass ratio of 1:1.5 to obtain flux 1;

[0105] S3. An aluminum ingot with a purity of ≥99.8% was placed in a resistance melting furnace and heated to 680°C to completely melt it into a liquid state. Industrially pure magnesium with a purity of ≥99.5% was added and stirred at 120 rpm for 20 min. An additive and flux 1 were added and stirred at 120 rpm for 15 min to obtain a mixed solution 2, wherein the mass ratio of the aluminum ingot, industrially pure magnesium, additive, and flux 1 was 90:3:0.1:0.3;

[0106] S4. Argon and chlorine were mixed in a volume ratio of 6:1 to obtain a mixed gas 2;

[0107] S5. The mixed gas 2 was introduced into the mixed liquid 2 at a gas flow rate of 0.6 L / min. The mixture was refined at a speed of 100 rpm for 25 min. After the refining was completed, the mixture was allowed to stand for 8 min to obtain a refined liquid 2. The refined liquid 2 was cast into a mold preheated to 230°C at a casting speed of 4 kg / s. The mold was cooled at a cooling rate of 8°C / s to obtain an aluminum alloy billet 2.

[0108] S6. The aluminum alloy billet 2 is forged by heating the billet to 480° C. and forging it three times on a forging device with a forging ratio controlled at 3. After forging, a buffer layer that meets the specifications is formed.

[0109] Example 6: A method for preparing a buffer layer of a high-strength aluminum alloy current collector, comprising the following steps:

[0110] S1. Titanium and boron were mixed in a mass ratio of 0.1:0.1 to obtain additive 2;

[0111] S2. Potassium chloride and sodium chloride were mixed in a mass ratio of 1.1:2 to obtain flux 1;

[0112] S3. An aluminum ingot with a purity of ≥99.8% was placed in a resistance melting furnace and heated to 690°C to completely melt it into a liquid state. Industrially pure magnesium with a purity of ≥99.5% was added and stirred at 140 rpm for 23 min. An additive and flux 1 were added and stirred at 140 rpm for 17 min to obtain a mixed solution 2, wherein the mass ratio of the aluminum ingot, industrially pure magnesium, additive, and flux 1 was 92:4:0.2:0.6;

[0113] S4. Argon and chlorine were mixed in a volume ratio of 6:1 to obtain a mixed gas 2;

[0114] S5. The mixed gas 2 was introduced into the mixed liquid 2 at a gas flow rate of 0.8 L / min. The mixture was refined at a speed of 120 rpm for 28 min. After the refining was completed, the mixture was allowed to stand for 10 min to obtain a refined liquid 2. The refined liquid 2 was cast into a mold preheated to 250°C at a casting speed of 4.5 kg / s. The mold was cooled at a cooling rate of 9°C / s to obtain an aluminum alloy billet 2.

[0115] S6. The aluminum alloy billet 2 is forged by heating the billet to 500° C. and forging it four times on a forging device with a forging ratio controlled at 4. After forging, a buffer layer that meets the specifications is formed.

[0116] Example 7: A method for preparing a buffer layer of a high-strength aluminum alloy current collector, comprising the following steps:

[0117] S1. Titanium and boron were mixed in a mass ratio of 0.2:0.15 to obtain additive 2;

[0118] S2. Potassium chloride and sodium chloride were mixed in a mass ratio of 1.2:2.5 to obtain flux 1;

[0119] S3. An aluminum ingot with a purity of ≥99.8% was placed in a resistance melting furnace and heated to 700°C to completely melt it into a liquid state. Industrially pure magnesium with a purity of ≥99.5% was added and stirred at 160 rpm for 26 min. An additive and flux 1 were added and stirred at 160 rpm for 18 min to obtain a mixed solution 2, wherein the mass ratio of the aluminum ingot, industrially pure magnesium, additive and flux 1 was 94:5:0.4:0.8;

[0120] S4. Argon and chlorine were mixed in a volume ratio of 6:1 to obtain a mixed gas 2;

[0121] S5. The mixed gas 2 was introduced into the mixed liquid 2 at a gas flow rate of 1.0 L / min. The mixture was refined at a speed of 140 rpm for 30 min. After the refining was completed, the mixture was allowed to stand for 11 min to obtain a refined liquid 2. The refined liquid 2 was cast into a mold preheated to 260 ° C at a casting speed of 5 kg / s. The mold was cooled at a cooling rate of 10 ° C / s to obtain an aluminum alloy billet 2;

[0122] S6. The aluminum alloy billet 2 is forged by heating the billet to 510° C. and forging it three times on a forging device with a forging ratio controlled at 3. After forging, a buffer layer that meets the specifications is formed.

[0123] Example 8: A method for preparing a buffer layer of a high-strength aluminum alloy current collector, comprising the following steps:

[0124] S1. Titanium and boron were mixed in a mass ratio of 0.3:0.2 to obtain additive 2;

[0125] S2. Potassium chloride and sodium chloride were mixed in a mass ratio of 1.2:3 to obtain flux 1;

[0126] S3. An aluminum ingot with a purity of ≥99.8% was placed in a resistance melting furnace and heated to 720°C to completely melt it into a liquid state. Industrially pure magnesium with a purity of ≥99.5% was added and stirred at 180 rpm for 30 min. An additive and flux 1 were added and stirred at 180 rpm for 20 min to obtain a mixed solution 2, wherein the mass ratio of the aluminum ingot, industrially pure magnesium, additive, and flux 1 was 95:6:0.5:1;

[0127] S4. Argon and chlorine were mixed in a volume ratio of 6:1 to obtain a mixed gas 2;

[0128] S5. The mixed gas 2 was introduced into the mixed liquid 2 at a gas flow rate of 1.2 L / min. The mixture was refined at a speed of 150 rpm for 35 min. After the refining was completed, the mixture was allowed to stand for 12 min to obtain a refined liquid 2. The refined liquid 2 was cast into a mold preheated to 280 ° C at a casting speed of 6 kg / s. The mold was cooled at a cooling rate of 12 ° C / s to obtain an aluminum alloy billet 2;

[0129] S6. The aluminum alloy billet 2 is forged by heating the billet to 530° C. and forging it five times on a forging device with a forging ratio controlled at 5. After forging, a buffer layer that meets the specifications is formed.

[0130] Example 9: A method for preparing a reinforcement layer of a high-strength aluminum alloy current collector, comprising the following steps:

[0131] S1. Zirconium and vanadium were mixed in a mass ratio of 0.05:0.05 to obtain additive 3;

[0132] S2. Potassium chloride and sodium chloride were mixed in a mass ratio of 0.1:0.4 to obtain flux 2;

[0133] S3. An aluminum ingot with a purity of ≥99.9% was placed in an electromagnetic induction melting furnace and heated to 730°C to completely melt it into a liquid state. Industrially pure copper with a purity of ≥99.6% and industrially pure magnesium with a purity of ≥99.5% were added and stirred at a stirring frequency of 150 Hz for 30 minutes. Additive 3 was then added and stirred at a stirring frequency of 150 Hz for a further 25 minutes to obtain a mixed solution 3.

[0134] S4. Argon and chlorine were mixed in a volume ratio of 8:1 to obtain a mixed gas 3;

[0135] S5. The mixed gas 3 was passed into the mixed solution 3 at a gas flow rate of 0.8 L / min. The mixture was refined for 30 min at a stirring frequency of 150 Hz, and then the flux 2 was added. The mixture was stirred for 10 min and then allowed to stand for 10 min. A sodium salt modifier was then added and stirred for 10 min at a stirring frequency of 150 Hz and then kept warm for 5 min to obtain an aluminum alloy billet 3, wherein the mass ratio of the aluminum ingot, commercially pure copper, commercially pure magnesium, the additive 3, the flux 2, and the sodium salt modifier was 80:4:2:0.1:0.5:0.1;

[0136] S6. Cast the aluminum alloy billet 3 into a mold preheated to 250°C at a casting speed of 5kg / s. Cool the mold at a cooling speed of 12°C / s. After the alloy is completely solidified, take it out of the mold, heat it to 500°C, and roll it three times on a hot rolling mill with the total rolling deformation controlled at 60%. After hot rolling, heat it to 530°C and keep it for 2h. Water-quench it, and then heat the quenched alloy to 150°C and keep it for 6h. Finally, machine the aluminum alloy according to the design size of the collector to obtain a reinforcement layer.

[0137] Example 10: A method for preparing a reinforcement layer of a high-strength aluminum alloy current collector, comprising the following steps:

[0138] S1. Zirconium and vanadium were mixed in a mass ratio of 0.15:0.1 to obtain additive 3;

[0139] S2. Potassium chloride and sodium chloride were mixed in a mass ratio of 0.13:0.5 to obtain flux 2;

[0140] S3. An aluminum ingot with a purity of ≥99.9% was placed in an electromagnetic induction melting furnace and heated to 740°C to completely melt it into a liquid state. Industrially pure copper with a purity of ≥99.6% and industrially pure magnesium with a purity of ≥99.5% were added and stirred at a stirring frequency of 170 Hz for 33 minutes. Additive 3 was then added and stirred at a stirring frequency of 170 Hz for a further 27 minutes to obtain a mixed solution 3.

[0141] S4. Argon and chlorine were mixed in a volume ratio of 8:1 to obtain a mixed gas 3;

[0142] S5. The mixed gas 3 was passed into the mixed solution 3 at a gas flow rate of 1.0 L / min. The mixture was refined for 33 min at a stirring frequency of 170 Hz, and then the flux 2 was added. The mixture was stirred for 12 min and then allowed to stand for 12 min. A sodium salt modifier was then added and stirred for 11 min at a stirring frequency of 170 Hz and then kept warm for 7 min to obtain an aluminum alloy billet 3, wherein the mass ratio of the aluminum ingot, commercially pure copper, commercially pure magnesium, the additive 3, the flux 2, and the sodium salt modifier was 83:6:3:0.3:0.7:0.2;

[0143] S6. Cast the aluminum alloy billet 3 into a mold preheated to 270°C at a casting speed of 6 kg / s. Cool the mold at a cooling speed of 14°C / s. After the alloy is completely solidified, take it out of the mold, heat it to 520°C, and roll it on a hot rolling mill four times. The total rolling deformation is controlled at 65%. After hot rolling, heat it to 535°C and keep it for 2.5 hours. Water-quench it, and then heat the quenched alloy to 160°C and keep it for 6.5 hours. Finally, machine the aluminum alloy according to the designed size of the collecting pipe to obtain a reinforcement layer.

[0144] Example 11: A method for preparing a reinforcement layer of a high-strength aluminum alloy current collector, comprising the following steps:

[0145] S1. Zirconium and vanadium were mixed in a mass ratio of 0.25:0.15 to obtain additive 3;

[0146] S2. Potassium chloride and sodium chloride were mixed in a mass ratio of 0.16:0.7 to obtain flux 2;

[0147] S3. An aluminum ingot with a purity of ≥99.9% was placed in an electromagnetic induction melting furnace and heated to 750°C to completely melt it into a liquid state. Industrially pure copper with a purity of ≥99.6% and industrially pure magnesium with a purity of ≥99.5% were added and stirred at a stirring frequency of 190 Hz for 36 minutes. Additive 3 was then added and stirred at a stirring frequency of 180 Hz for a further 28 minutes to obtain a mixed solution 3.

[0148] S4. Argon and chlorine were mixed in a volume ratio of 8:1 to obtain a mixed gas 3;

[0149] S5. The mixed gas 3 was passed into the mixed solution 3 at a gas flow rate of 1.2 L / min. The mixture was refined for 36 min at a stirring frequency of 180 Hz, and then the flux 2 was added. The mixture was stirred for 13 min and then allowed to stand for 14 min. A sodium salt modifier was then added and stirred for 12 min at a stirring frequency of 190 Hz and then kept warm for 9 min to obtain an aluminum alloy billet 3, wherein the mass ratio of the aluminum ingot, commercially pure copper, commercially pure magnesium, the additive 3, the flux 2, and the sodium salt modifier was 86:7:4:0.4:0.8:0.25;

[0150] S6. Cast the aluminum alloy billet 3 into a mold preheated to 280°C at a casting speed of 6 kg / s. Cool the mold at a cooling speed of 16°C / s. After the alloy is completely solidified, take it out of the mold, heat it to 540°C, and roll it on a hot rolling mill four times. The total rolling deformation is controlled at 75%. After hot rolling, heat it to 545°C and keep it warm for 2.8 hours. Water-cooled quenching is performed, and the quenched alloy is then heated to 170°C and kept warm for 7.5 hours. Finally, the aluminum alloy is machined according to the design size of the collector to obtain a reinforcement layer.

[0151] Example 12: A method for preparing a reinforcement layer of a high-strength aluminum alloy current collector, comprising the following steps:

[0152] S1. Zirconium and vanadium were mixed in a mass ratio of 0.3:0.2 to obtain additive 3;

[0153] S2. Potassium chloride and sodium chloride were mixed in a mass ratio of 0.2:0.8 to obtain flux 2;

[0154] S3. An aluminum ingot with a purity of ≥99.9% was placed in an electromagnetic induction melting furnace and heated to 760°C to completely melt it into a liquid state. Industrially pure copper with a purity of ≥99.6% and industrially pure magnesium with a purity of ≥99.5% were added and stirred at a stirring frequency of 200 Hz for 40 minutes. Additive 3 was then added and stirred at a stirring frequency of 200 Hz for 30 minutes to obtain a mixed solution 3.

[0155] S4. Argon and chlorine were mixed in a volume ratio of 8:1 to obtain a mixed gas 3;

[0156] S5. The mixed gas 3 was passed into the mixed solution 3 at a gas flow rate of 1.5 L / min. The mixture was refined for 40 min at a stirring frequency of 200 Hz, and then the flux 2 was added. The stirring was continued for 15 min and then allowed to stand for 15 min. A sodium salt modifier was then added and stirred for 12 min at a stirring frequency of 200 Hz and then kept warm for 10 min to obtain an aluminum alloy billet 3, wherein the mass ratio of the aluminum ingot, commercially pure copper, commercially pure magnesium, the additive 3, the flux 2 and the sodium salt modifier was 90:8:5:0.5:1:0.3;

[0157] S6. Cast the aluminum alloy billet 3 into a mold preheated to 300℃ at a casting speed of 7kg / s. Cool the mold at a cooling speed of 18℃ / s. After the alloy is completely solidified, take it out of the mold, heat it to 550℃, and roll it on a hot rolling mill for 5 times. The total rolling deformation is controlled at 80%. After hot rolling, heat it to 550℃ and keep it warm for 3h. Water-cooled quenching is performed. The quenched alloy is then heated to 180℃ and kept warm for 8h. Finally, the aluminum alloy is machined according to the design size of the collector to obtain a reinforcement layer.

[0158] Example 13: A method for preparing a wear-resistant layer of a high-strength aluminum alloy header, comprising the following steps:

[0159] S1. Yttrium and boron were mixed in a mass ratio of 0.05:0.05 to obtain additive 4;

[0160] S2. Potassium chloride, sodium chloride and calcium fluoride were mixed in a mass ratio of 25:40:5 to obtain flux 3;

[0161] S3. An aluminum ingot with a purity of ≥99.9% was placed in an electromagnetic induction melting furnace and heated to 750°C to completely melt it into a liquid state. Argon gas was introduced into the furnace, and silicon carbide particles with a purity of ≥99.7% were added. The mixture was stirred at a stirring frequency of 200 Hz for 40 minutes. Then, industrial pure copper with a purity of ≥99.5% and additive 4 were added, and stirring was continued for 20 minutes to obtain a mixed solution 4.

[0162] S4. Argon and chlorine were mixed in a volume ratio of 10:1 to obtain a mixed gas 4;

[0163] S5. The mixed gas 4 was passed into the mixed liquid 4, the gas flow rate of the mixed gas 4 was 1 L / min, refined for 35min, then the flux 3 was added, stirred and allowed to stand for 12min, then the sodium salt modifier was added, stirred and kept warm for 6min to obtain a refined liquid 4, the refined liquid 4 was cast into a mold preheated to 280 ° C, the casting speed was controlled to 6kg / s, after the casting was completed, the mold was cooled, the cooling rate was 15 ° C / s, to obtain an alloy billet 4, wherein the mass ratio of aluminum ingot, silicon carbide particles, industrial pure copper, additive 4, flux 3 and sodium salt modifier was 70:10:3:0.1:0.6:0.15;

[0164] S5. Heat alloy billet 4 to 520°C and extrude it on a hot extruder with an extrusion ratio of 10. Then, heat the alloy to 540°C and keep it at this temperature for 2.5 hours. Then, quench it in cold water. Heat the quenched alloy to 160°C and keep it at this temperature for 7 hours. Finally, machine the alloy according to the size of the manifold to obtain a wear-resistant layer.

[0165] Example 14: A method for preparing a wear-resistant layer of a high-strength aluminum alloy header, comprising the following steps:

[0166] S1. Yttrium and boron were mixed in a mass ratio of 0.2:0.2 to obtain additive 4;

[0167] S2. Potassium chloride, sodium chloride and calcium fluoride were mixed in a mass ratio of 30:45:10 to obtain flux 3;

[0168] S3. An aluminum ingot with a purity of ≥99.9% was placed in an electromagnetic induction melting furnace and heated to 760°C to completely melt it into a liquid state. Argon gas was introduced into the furnace, and silicon carbide particles with a purity of ≥99.7% were added. The mixture was stirred at a stirring frequency of 220 Hz for 43 minutes. Then, industrial pure copper with a purity of ≥99.5% and additive 4 were added. Stirring was continued for 22 minutes to obtain a mixed solution 4.

[0169] S4. Argon and chlorine were mixed in a volume ratio of 10:1 to obtain a mixed gas 4;

[0170] S5. The mixed gas 4 was passed into the mixed liquid 4, the gas flow rate of the mixed gas 4 was 1.3 L / min, refined for 40 min, then the flux 3 was added, stirred and allowed to stand for 14 min, then the sodium salt modifier was added, stirred and kept warm for 8 min to obtain a refined liquid 4, the refined liquid 4 was cast into a mold preheated to 290 ° C, the casting speed was controlled to 6.5 kg / s, after the casting was completed, the mold was cooled at a cooling rate of 17 ° C / s to obtain an alloy billet 4, wherein the mass ratio of aluminum ingot, silicon carbide particles, industrial pure copper, additive 4, flux 3 and sodium salt modifier was 75:13:5:0.3:0.8:0.25;

[0171] S5. Alloy billet 4 is heated to 530°C and extruded on a hot extruder with an extrusion ratio of 12. The alloy is then heated to 545°C and held at this temperature for 3 hours. The alloy is then cold-quenched. The quenched alloy is then heated to 170°C and held at this temperature for 7.5 hours. Finally, the alloy is machined according to the size of the manifold to obtain a wear-resistant layer.

[0172] Example 15: A method for preparing a wear-resistant layer of a high-strength aluminum alloy header, comprising the following steps:

[0173] S1. Yttrium and boron were mixed in a mass ratio of 0.3:0.4 to obtain additive 4;

[0174] S2. Potassium chloride, sodium chloride and calcium fluoride were mixed in a mass ratio of 35:50:12 to obtain flux 3;

[0175] S3. An aluminum ingot with a purity of ≥99.9% was placed in an electromagnetic induction melting furnace and heated to 770°C to completely melt it into a liquid state. Argon gas was introduced into the furnace, and silicon carbide particles with a purity of ≥99.7% were added. The mixture was stirred at a stirring frequency of 240 Hz for 46 minutes. Then, industrial pure copper with a purity of ≥99.5% and additive 4 were added, and stirring was continued for 24 minutes to obtain a mixed solution 4.

[0176] S4. Argon and chlorine were mixed in a volume ratio of 10:1 to obtain a mixed gas 4;

[0177] S5. The mixed gas 4 was passed into the mixed liquid 4, the gas flow rate of the mixed gas 4 was 1.6 L / min, refined for 45min, then the flux 3 was added, stirred and allowed to stand for 16min, then the sodium salt modifier was added, stirred and kept warm for 9min to obtain a refined liquid 4, the refined liquid 4 was cast into a mold preheated to 300 ℃, the casting speed was controlled to 7.5kg / s, and after the casting was completed, the mold was cooled at a cooling rate of 19 ℃ / s to obtain an alloy billet 4, wherein the mass ratio of aluminum ingot, silicon carbide particles, industrial pure copper, additive 4, flux 3 and sodium salt modifier was 80:16:6:0.6:1.0:0.30;

[0178] S5. Alloy billet 4 is heated to 550°C and extruded on a hot extruder with an extrusion ratio of 14. The alloy is then heated to 550°C and held at this temperature for 3.5 hours. The alloy is then cold-quenched. The quenched alloy is heated to 180°C and held at this temperature for 8 hours. Finally, the alloy is machined according to the size of the manifold to obtain a wear-resistant layer.

[0179] Example 16: A method for preparing a wear-resistant layer of a high-strength aluminum alloy header, comprising the following steps:

[0180] S1. Yttrium and boron were mixed in a mass ratio of 0.5:0.5 to obtain additive 4;

[0181] S2. Potassium chloride, sodium chloride and calcium fluoride were mixed in a mass ratio of 40:60:15 to obtain flux 3;

[0182] S3. An aluminum ingot with a purity of ≥99.9% was placed in an electromagnetic induction melting furnace and heated to 780°C to completely melt it into a liquid state. Argon gas was introduced into the furnace, and silicon carbide particles with a purity of ≥99.7% were added. The mixture was stirred at a stirring frequency of 250 Hz for 50 minutes. Then, industrial pure copper with a purity of ≥99.5% and additive 4 were added. The mixture was stirred for a further 25 minutes to obtain a mixed solution 4.

[0183] S4. Argon and chlorine were mixed in a volume ratio of 10:1 to obtain a mixed gas 4;

[0184] S5. The mixed gas 4 was passed into the mixed liquid 4, the gas flow rate of the mixed gas 4 was 1.8 L / min, refined for 50 min, then the flux 3 was added, stirred and allowed to stand for 18 min, then the sodium salt modifier was added, stirred and kept warm for 10 min to obtain a refined liquid 4, the refined liquid 4 was cast into a mold preheated to 320 ° C, the casting speed was controlled to 8 kg / s, after the casting was completed, the mold was cooled at a cooling rate of 20 ° C / s to obtain an alloy billet 4, wherein the mass ratio of aluminum ingot, silicon carbide particles, industrial pure copper, additive 4, flux 3 and sodium salt modifier was 85:20:8:1:1.2:0.35;

[0185] S5. Heat alloy billet 4 to 560°C and extrude it on a hot extruder with an extrusion ratio of 15. Then, heat the alloy to 560°C and keep it at that temperature for 3.5 hours. Then, quench it in cold water. Heat the quenched alloy to 190°C and keep it at that temperature for 9 hours. Finally, machine the alloy according to the size of the manifold to obtain a wear-resistant layer.

[0186] Example 17: A method for preparing a high-strength aluminum alloy header, comprising the following steps:

[0187] S1. The main reinforcement ribs, obliquely distributed secondary reinforcement ribs and reinforcement rings are processed into a mesh-like distribution between the corrosion-resistant layer with a thickness of 1.5mm, the buffer layer with a thickness of 1mm, the reinforcement layer with a thickness of 1.5mm and the wear-resistant layer with a thickness of 0.8mm by milling technology. The height of the main reinforcement ribs is 1mm and the width is 0.5mm. The main reinforcement ribs pass through the buffer layer, the reinforcement layer and the wear-resistant layer in sequence from the corrosion-resistant layer to enhance the overall compression and deformation resistance of the manifold. The height of the secondary reinforcement ribs is 0.8mm and the width is 0.4mm, which are used to improve the torsion and bending resistance of the manifold. The thickness of the reinforcement ring is 1mm and it is set at the key position to further enhance the local strength of the manifold. These reinforcement structures not only connect the corrosion-resistant layer, the buffer layer, the reinforcement layer and the wear-resistant layer, but also connect the corrosion-resistant layer, the buffer layer, the reinforcement layer and the wear-resistant layer. The role of the layer can also effectively improve the overall mechanical properties of the collecting pipe. At the connection part of the collecting pipe, a plug-in connection structure is made by combining mechanical processing and assembly. First, the connecting pipe, the sealing rubber ring groove and the locking nut groove are made by mechanical processing, and then the sealing rubber ring and the locking nut are installed. Finally, the reinforcing bushing is inserted. This structure can not only ensure the sealing of the connection part, but also improve the compression and tensile strength of the connection part, thereby ensuring the reliability of the collecting pipe during use. After the corrosion-resistant layer, the buffer layer, the reinforcing layer and the wear-resistant layer are synthesized into the collecting pipe, sodium phosphate, sodium hydroxide and sodium silicate are added to deionized water and stirred evenly to obtain an electrolyte, wherein the mass ratio of sodium phosphate, sodium hydroxide, sodium silicate and deionized water is 5:3:5:73;

[0188] S2. The wear-resistant layer of the header was immersed in a sodium hydroxide solution at a temperature of 60°C and a concentration of 50g / L for 10min, and then immersed in a nitric acid solution at a temperature of 40°C and a concentration of 30g / L for 5min;

[0189] S3. Place the treated wear-resistant layer of the collector into an electrolytic cell filled with electrolyte, use a stainless steel plate as the cathode, and conduct electricity at a voltage of 250V and a current of 8A / dm 2 The plasma electrolytic oxidation treatment was carried out at a current density of 100 nm and 20°C for 50 min to form an oxide film with a thickness of 20 μm.

[0190] S4. Concentrated nitric acid and concentrated sulfuric acid were mixed in a volume ratio of 1:3 to obtain a mixed acid solution;

[0191] S5. Trimethylaluminum, tetraethylsilane and magnesium acetylacetonate were mixed in a mass ratio of 40:30:10 to obtain an aluminum alloy precursor;

[0192] S6. Place the carbon nanotubes in a mixed acid solution, ultrasonically treat them at 60°C for 2 hours, then repeatedly rinse them with deionized water until they are neutral, and vacuum dry them at 80°C for 2 hours. Fix the manifold on the sample stage in the reactor, adjust the distance between the sample stage and the gas nozzle to 10 cm, place the manifold in the reactor, introduce argon as a carrier gas, and control the flow rate of argon at 50 mL / min. Then heat the reactor to 500°C, introduce mixed gas 5, and deposit for 2 hours at 10 Pa to obtain a nanocoating with a thickness of 3 μm, wherein the concentration of carbon nanotubes in the mixed gas 5 is 0.1 g / L, and the concentration of the aluminum alloy precursor is 1 mol / L, thus obtaining a high-strength aluminum alloy manifold.

[0193] Example 18: A method for preparing a high-strength aluminum alloy header, comprising the following steps:

[0194] S1. The corrosion-resistant layer with a thickness of 1.7mm, the buffer layer with a thickness of 1.2mm, the reinforcement layer with a thickness of 1.5-1.7-1.9-2mm and the wear-resistant layer with a thickness of 0.9mm are processed by milling technology to form main reinforcement ribs distributed in a mesh shape, secondary reinforcement ribs distributed obliquely and reinforcement rings. The height of the main reinforcement ribs is 1.2mm and the width is 0.6mm. The main reinforcement ribs run through the buffer layer, the reinforcement layer and the wear-resistant layer from the corrosion-resistant layer in sequence to enhance the overall compression and deformation resistance of the manifold. The height of the secondary reinforcement ribs is 1.0mm and the width is 0.5mm, which are used to improve the torsion and bending resistance of the manifold. The thickness of the reinforcement rings is 1.2mm and is set at key positions to further enhance the local strength of the manifold. These reinforcement structures not only connect the corrosion-resistant layer and the buffer layer, but also play a role in strengthening the manifold. The role of the corrosion-resistant layer, the reinforcement layer and the wear-resistant layer can also effectively improve the overall mechanical properties of the collector. At the connection part of the collector, a plug-in connection structure is made by combining machining and assembly. The connecting pipe, the sealing rubber ring groove and the locking nut groove are first made by machining, and then the sealing rubber ring and the locking nut are installed. Finally, the reinforcing bushing is inserted. This structure can not only ensure the sealing of the connection part, but also improve the compression and tensile strength of the connection part, thereby ensuring the reliability of the collector during use. After the corrosion-resistant layer, the buffer layer, the reinforcement layer and the wear-resistant layer are synthesized into the collector, sodium phosphate, sodium hydroxide and sodium silicate are added to deionized water and stirred evenly to obtain an electrolyte, wherein the mass ratio of sodium phosphate, sodium hydroxide, sodium silicate and deionized water is 7:5:7:78;

[0195] S2. The wear-resistant layer of the manifold was immersed in a sodium hydroxide solution at a temperature of 65°C and a concentration of 60g / L for 12min, and then immersed in a nitric acid solution at a temperature of 45°C and a concentration of 35g / L for 6min;

[0196] S3. Place the treated wear-resistant layer of the collector into an electrolytic cell filled with electrolyte, use a stainless steel plate as the cathode, and conduct electricity at a voltage of 280V and a current of 9A / dm 2 The plasma electrolytic oxidation treatment was carried out at a current density of 100 nm and 23°C for 55 min to form an oxide film with a thickness of 25 μm.

[0197] S4. Concentrated nitric acid and concentrated sulfuric acid were mixed in a volume ratio of 1:3 to obtain a mixed acid solution;

[0198] S5. Trimethylaluminum, tetraethylsilane and magnesium acetylacetonate were mixed in a mass ratio of 43:33:13 to obtain an aluminum alloy precursor;

[0199] S6. Place carbon nanotubes in a mixed acid solution, ultrasonically treat at 65°C for 2.5 hours, then repeatedly rinse with deionized water until neutral, and vacuum dry at 85°C for 2.5 hours. Fix the manifold on the sample stage in the reactor, adjust the distance between the sample stage and the gas nozzle to 12 cm, place the manifold in the reactor, introduce argon as a carrier gas, and control the flow rate of argon at 70 mL / min. Then heat the reactor to 550°C, introduce mixed gas 5, and under the condition of 13 Pa, the deposition time is 2.5 hours to obtain a nano-coating with a thickness of 4 μm, wherein the concentration of carbon nanotubes in the mixed gas 5 is 0.15 g / L, and the concentration of the aluminum alloy precursor is 2 mol / L, that is, a high-strength aluminum alloy manifold is obtained.

[0200] Example 19: A method for preparing a high-strength aluminum alloy header, comprising the following steps:

[0201] S1. The corrosion-resistant layer with a thickness of 1.8mm, the buffer layer with a thickness of 1.4mm, the reinforcement layer with a thickness of 1.9mm and the wear-resistant layer with a thickness of 1.1mm are processed by milling technology to form main reinforcement ribs with a mesh distribution, obliquely distributed secondary reinforcement ribs and reinforcement rings. The height of the main reinforcement ribs is 1.4mm and the width is 0.7mm. The main reinforcement ribs run through the buffer layer, the reinforcement layer and the wear-resistant layer from the corrosion-resistant layer in sequence to enhance the overall compression and deformation resistance of the manifold. The height of the secondary reinforcement ribs is 1.1mm and the width is 0.4mm, which are used to improve the torsion and bending resistance of the manifold. The thickness of the reinforcement ring is 1.4mm and it is set at the key position to further enhance the local strength of the manifold. These reinforcement structures not only connect the corrosion-resistant layer, the buffer layer and the reinforcement layer, but also connect the main reinforcement ribs to the wear-resistant layer. and the wear-resistant layer, and can also effectively improve the overall mechanical properties of the collecting pipe. At the connection part of the collecting pipe, a plug-in connection structure is made by combining mechanical processing and assembly. First, the connecting pipe, the sealing rubber ring groove and the locking nut groove are made by mechanical processing, and then the sealing rubber ring and the locking nut are installed. Finally, the reinforcing bushing is inserted. This structure can not only ensure the sealing of the connection part, but also improve the compression and tensile strength of the connection part, and ensure the reliability of the collecting pipe during use. After the corrosion-resistant layer, the buffer layer, the reinforcing layer and the wear-resistant layer are synthesized into the collecting pipe, sodium phosphate, sodium hydroxide and sodium silicate are added to deionized water and stirred evenly to obtain an electrolyte, wherein the mass ratio of sodium phosphate, sodium hydroxide, sodium silicate and deionized water is 9:6:8:82;

[0202] S2. The wear-resistant surface of the header was immersed in a sodium hydroxide solution at a temperature of 70°C and a concentration of 70g / L for 14min, and then immersed in a nitric acid solution at a temperature of 50°C and a concentration of 40g / L for 8min;

[0203] S3. Place the treated wear-resistant layer of the collector into an electrolytic cell filled with electrolyte, use a stainless steel plate as the cathode, and conduct electricity at a voltage of 320V and a current of 10A / dm 2 The plasma electrolytic oxidation treatment was carried out at a current density of 100 nm and 26°C for 60 min to form an oxide film with a thickness of 28 μm.

[0204] S4. Concentrated nitric acid and concentrated sulfuric acid were mixed in a volume ratio of 1:3 to obtain a mixed acid solution;

[0205] S5. Trimethylaluminum, tetraethylsilane and magnesium acetylacetonate were mixed in a mass ratio of 46:37:17 to obtain an aluminum alloy precursor;

[0206] S6. Place the carbon nanotubes in a mixed acid solution, ultrasonically treat them at 70°C for 3 hours, then repeatedly rinse them with deionized water until they are neutral, and vacuum dry them at 90°C for 3 hours. Fix the manifold on the sample stage in the reactor, adjust the distance between the sample stage and the gas nozzle to 14 cm, place the manifold in the reactor, introduce argon as a carrier gas, and control the flow rate of argon at 80 mL / min. Then heat the reactor to 580°C, introduce mixed gas 5, and deposit for 2 hours at 16 Pa to obtain a nanocoating with a thickness of 3 μm, wherein the concentration of carbon nanotubes in the mixed gas 5 is 0.2 g / L, and the concentration of the aluminum alloy precursor is 2.5 mol / L, thus obtaining a high-strength aluminum alloy manifold.

[0207] Example 20: A method for preparing a high-strength aluminum alloy header, comprising the following steps:

[0208] S1. The corrosion-resistant layer with a thickness of 2mm, the buffer layer with a thickness of 1.5mm, the reinforcement layer with a thickness of 2mm and the wear-resistant layer with a thickness of 1.2mm are processed by milling technology to form main reinforcement ribs with a mesh distribution, obliquely distributed secondary reinforcement ribs and reinforcement rings. The height of the main reinforcement ribs is 1.5mm and the width is 0.8mm. The main reinforcement ribs run through the buffer layer, the reinforcement layer and the wear-resistant layer from the corrosion-resistant layer in sequence to enhance the overall compression and deformation resistance of the manifold. The height of the secondary reinforcement ribs is 1.2mm and the width is 0.6mm, which are used to improve the torsion and bending resistance of the manifold. The thickness of the reinforcement ring is 1.5mm and it is set at the key position to further enhance the local strength of the manifold. These reinforcement structures not only connect the corrosion-resistant layer, the buffer layer, the reinforcement layer and the wear-resistant layer, but also connect the main reinforcement ribs to the wear-resistant layer. The role of the layer can also effectively improve the overall mechanical properties of the collecting pipe. At the connection part of the collecting pipe, a plug-in connection structure is made by combining mechanical processing and assembly. First, the connecting pipe, the sealing rubber ring groove and the locking nut groove are made by mechanical processing, and then the sealing rubber ring and the locking nut are installed. Finally, the reinforcing bushing is inserted. This structure can not only ensure the sealing of the connection part, but also improve the compression and tensile strength of the connection part, thereby ensuring the reliability of the collecting pipe during use. After the corrosion-resistant layer, the buffer layer, the reinforcing layer and the wear-resistant layer are synthesized into the collecting pipe, sodium phosphate, sodium hydroxide and sodium silicate are added to deionized water and stirred evenly to obtain an electrolyte, wherein the mass ratio of sodium phosphate, sodium hydroxide, sodium silicate and deionized water is 10:7:10:87;

[0209] S2. The wear-resistant layer of the header was immersed in a sodium hydroxide solution at a temperature of 80°C and a concentration of 80g / L for 15min, and then immersed in a nitric acid solution at a temperature of 60°C and a concentration of 50g / L for 10min;

[0210] S3. Place the treated wear-resistant layer of the collector into an electrolytic cell filled with electrolyte, use a stainless steel plate as the cathode, and conduct electricity at a voltage of 350V and a current of 12A / dm 2 The plasma electrolytic oxidation treatment was carried out at a current density of 100 nm and 30°C for 70 min to form an oxide film with a thickness of 30 μm.

[0211] S4. Concentrated nitric acid and concentrated sulfuric acid were mixed in a volume ratio of 1:3 to obtain a mixed acid solution;

[0212] S5. Trimethylaluminum, tetraethylsilane and magnesium acetylacetonate were mixed in a mass ratio of 50:40:20 to obtain an aluminum alloy precursor;

[0213] S6. Place the carbon nanotubes in a mixed acid solution, ultrasonically treat them at 80°C for 3 hours, then repeatedly rinse with deionized water until neutral, and vacuum dry them at 100°C for 3 hours. Fix the manifold on the sample stage in the reactor, adjust the distance between the sample stage and the gas nozzle to 15 cm, place the manifold in the reactor, introduce argon as a carrier gas, and control the flow rate of argon at 100 mL / min. Then heat the reactor to 600°C, introduce mixed gas 5, and under the condition of 20 Pa, the deposition time is 3 hours to obtain a nano-coating with a thickness of 5 μm, wherein the concentration of carbon nanotubes in the mixed gas 5 is 0.3 g / L, and the concentration of the aluminum alloy precursor is 3 mol / L, that is, a high-strength aluminum alloy manifold is obtained.

[0214] Comparative Example 1:

[0215] Compared with Example 17, this comparative example did not add a nano-coating during the preparation of the high-strength aluminum alloy current collecting pipe. The remaining steps and parameters were the same and will not be repeated in this comparative example. Finally, a high-strength aluminum alloy current collecting pipe was obtained.

[0216] Comparative Example 2:

[0217] Compared with Example 17, this comparative example did not add a corrosion-resistant layer during the preparation of the high-strength aluminum alloy current collecting pipe. The remaining steps and parameters were the same and will not be repeated in this comparative example. Finally, a high-strength aluminum alloy current collecting pipe was obtained.

[0218] Comparative Example 3:

[0219] Compared with Example 17, this comparative example did not add a buffer layer during the preparation of the high-strength aluminum alloy current collecting tube. The remaining steps and parameters were the same and will not be repeated in this comparative example. Finally, a high-strength aluminum alloy current collecting tube was obtained.

[0220] Comparative Example 4:

[0221] Compared with Example 17, this comparative example did not add a reinforcement layer during the preparation of the high-strength aluminum alloy current collecting tube. The remaining steps and parameters were the same and will not be repeated in this comparative example. Finally, a high-strength aluminum alloy current collecting tube was obtained.

[0222] Comparative Example 5:

[0223] Compared with Example 17, this comparative example only swaps the order of the "buffer layer" and the "reinforcement layer", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, a high-strength aluminum alloy collecting tube is obtained.

[0224] Comparative Example 6:

[0225] S1. The main reinforcement ribs, obliquely distributed secondary reinforcement ribs and reinforcement rings are processed into a mesh-like distribution between the corrosion-resistant layer with a thickness of 1.5mm, the buffer layer with a thickness of 1mm, the reinforcement layer with a thickness of 1.5mm and the wear-resistant layer with a thickness of 0.8mm by milling technology. The height of the main reinforcement ribs is 1mm and the width is 0.5mm. The main reinforcement ribs pass through the buffer layer, the reinforcement layer and the wear-resistant layer in sequence from the corrosion-resistant layer to enhance the overall compression and deformation resistance of the manifold. The height of the secondary reinforcement ribs is 0.8mm and the width is 0.4mm to improve the torsion and bending resistance of the manifold. The thickness of the reinforcement rings is 1mm and they are set at key positions to further enhance the local strength of the manifold. These reinforcement structures It not only plays the role of connecting the corrosion-resistant layer, buffer layer, reinforcement layer and wear-resistant layer, but also can effectively improve the overall mechanical properties of the collecting pipe. At the connection part of the collecting pipe, a plug-in connection structure is made by combining machining and assembly. First, the connecting pipe, sealing rubber ring groove and locking nut groove are made by machining, and then the sealing rubber ring and locking nut are installed. Finally, the reinforcing bushing is inserted. This structure can not only ensure the sealing of the connection part, but also improve the compression and tensile strength of the connection part, thereby ensuring the reliability of the collecting pipe during use. After the corrosion-resistant layer, buffer layer, reinforcement layer and wear-resistant layer are combined into the collecting pipe, concentrated nitric acid and concentrated sulfuric acid are mixed at a volume ratio of 1:3 to obtain a mixed acid solution;

[0226] S2 trimethylaluminum, tetraethylsilane and magnesium acetylacetonate were mixed in a mass ratio of 40:30:10 to obtain an aluminum alloy precursor;

[0227] S3. Place the carbon nanotubes in a mixed acid solution, ultrasonically treat them at 60°C for 2 hours, then repeatedly rinse them with deionized water until they are neutral, and vacuum dry them at 80°C for 2 hours. Fix the manifold on the sample stage in the reactor, adjust the distance between the sample stage and the gas nozzle to 10 cm, place the manifold in the reactor, introduce argon as a carrier gas, and control the flow rate of argon at 50 mL / min. Then heat the reactor to 500°C, introduce mixed gas 5, and under the condition of 10 Pa, the deposition time is 2 hours to obtain a nano-coating with a thickness of 3 μm, wherein the concentration of carbon nanotubes in the mixed gas 5 is 0.1 g / L, and the concentration of the aluminum alloy precursor is 1 mol / L, that is, a high-strength aluminum alloy manifold is obtained.

[0228] Performance Test: The high-strength aluminum alloy manifolds prepared in Examples 17 to 20 and Comparative Examples 1 to 6 were subjected to the following performance tests:

[0229] Hardness: Refer to GB / T230.1-2018 "Rockwell hardness test for metallic materials - Part 1: Test method" and use a Rockwell hardness tester with a main test force of 150kg to measure the surface hardness of the manifold.

[0230] Wear resistance: Refer to GB / T12444-2012 "Metallic Materials Wear Test Methods - Test Ring-Test Block Thawing Wear Test", use the test ring-test block sliding wear test device to test the amount of collector surface wear per unit time under a certain load and sliding speed;

[0231] Corrosion resistance: Refer to GB / T10125-2012 "Artificial atmosphere corrosion test salt spray test", place the manifold into the salt spray test chamber, spray continuously in 5% sodium chloride solution at 35°C, and record the time when the corrosion point appears;

[0232] Compressive strength: Refer to GB / T7314-2017 "Metallic Materials Room Temperature Compression Test Method", use a universal material testing machine, apply axial pressure to the manifold at a certain loading rate, and record the pressure when the manifold occurs;

[0233] Torsional strength: Refer to GB / T10128-2007 "Metallic Materials Room Temperature Torsion Test Method", use a torsion testing machine to apply torque to the manifold, and record the torque when the manifold breaks;

[0234] The results are shown in Table 1 below:

[0235] Table 1

[0236] project hardness wear resistance Corrosion resistance Compressive strength Torsional strength Example 17 HRB 90 0.05 mg / h 500h 450MPa 200N·m Example 18 HRB 95 0.04 mg / h 600h 480MPa 220N·m Example 19 HRB 98 0.035 mg / h 700h 500MPa 230N·m Example 20 HRB 100 0.03 mg / h 800h 520MPa 250N·m Comparative Example 1 HRB 85 0.07 mg / h 400h 400MPa 180N·m Comparative Example 2 HRB 80 0.08 mg / h 300h 380MPa 160N·m Comparative Example 3 HRB 82 0.075 mg / h 350h 400MPa 170N·m Comparative Example 4 HRB 75 0.1 mg / h 200h 350MPa 150N·m Comparative Example 5 HRB 88 0.06 mg / h 450h 430MPa 190N·m Comparative Example 6 HRB 88 0.065 mg / h 420h 420MPa 185N·m

[0237] Data Analysis:

[0238] Hardness: In Examples 17-20, with the optimization of the structural parameters of each layer and the improvement of the surface treatment process, the hardness is improved from HRB 90 to HRB 100. This is mainly attributed to the strengthening effect of the carbon nanotube-reinforced aluminum alloy composite material in the nanocoating, and the solid solution strengthening and work hardening effects of the alloying elements in the structure of each layer. For example, trace element additives such as zirconium and vanadium in the reinforcement layer refine the grains and improve the overall hardness. In contrast, in Example 1, no nanocoating was added, and the hardness dropped to HRB 85, ​​indicating that the nanocoating significantly improved the hardness. In Examples 2-4, the corrosion-resistant layer, buffer layer and reinforcement layer were missing respectively, and the hardness decreased significantly, indicating that the structure of each layer is crucial to maintaining the hardness of the collector, especially the reinforcement layer, whose strengthening phase formed by elements such as industrial pure copper and industrial pure magnesium has a significant effect on improving the hardness. In Example 5, the order of the buffer layer and the reinforcement layer was swapped, and the hardness decreased, indicating that the order of the structure of each layer affects the hardness, which may be related to the transmission and distribution of force. Although Comparative Example 6 has a nanocoating, no oxide film is prepared, and the hardness is similar to that of Comparative Example 5, indicating that the synergistic effect of the oxide film and the nanocoating has a certain influence on the hardness improvement. Without the oxide film, the strengthening effect of the nanocoating cannot be fully exerted.

[0239] Wear resistance: The wear rate of Examples 17-20 gradually decreased from 0.05 mg / h to 0.03 mg / h. This is because the friction-reducing and anti-wear properties of the nanocoating and the supporting and strengthening effects of each layer structure are continuously optimized. For example, the addition of silicon carbide particles in the wear-resistant layer, as well as the oxide film and nanocoating formed by the surface treatment process, jointly improve the wear resistance. In contrast, in Comparative Example 1, which does not have a nanocoating, the wear rate increased significantly to 0.07 mg / h, indicating that the nanocoating is a key factor in improving wear resistance. Comparative Examples 2-4 lack each layer structure, and the wear rate increased sharply. In particular, in Comparative Example 4, which lacks a reinforcement layer, the wear rate was as high as 0.1 mg / h, indicating that the reinforcement layer provides support for the wear-resistant layer, and the wear resistance decreased significantly after its absence. In Comparative Example 5, the order was changed, and the wear rate increased, indicating that a reasonable structural order is very important for wear resistance, which may affect the stress distribution and wear mechanism. Comparative Example 6 did not prepare an oxide film, and the wear rate was higher than that of Example 17, indicating that the oxide film plays an important role in wear resistance and works together with the nanocoating to protect the collector surface.

[0240] Corrosion Resistance: Examples 17-20 showed progressively improved corrosion resistance, with the time to corrosion pitting extending from 500 hours to 800 hours. This is attributed to the dual protection provided by the ceramic composite oxide film formed by plasma electrolytic oxidation and the nanocoating, which blocked the attack of the corrosive medium. Furthermore, the alloy components of each layer also possessed a certain degree of corrosion resistance. Comparative Example 1, which lacked the nanocoating, showed decreased corrosion resistance, with the time to corrosion pitting shortened to 400 hours, demonstrating that the nanocoating effectively blocks the corrosive medium. Comparative Examples 2-4, which lacked each layer, showed significantly reduced corrosion resistance. Comparative Example 2, lacking the corrosion-resistant layer and directly exposed to the corrosive medium, exhibited the worst corrosion resistance, with corrosion pitting appearing after only 300 hours, demonstrating that the corrosion-resistant layer is a key layer in resisting corrosion. Comparative Example 5, which had its corrosion resistance altered by changing the order of the layers, showed decreased corrosion resistance, indicating that the arrangement of the layers affects the penetration path of the corrosive medium and the protective effect. Comparative Example 6, which lacked an oxide film, showed a lower corrosion resistance than Example 17, lasting 420 hours. This demonstrates that the oxide film plays a fundamental protective role in corrosion resistance, synergistically improving corrosion resistance with the nanocoating.

[0241] Compressive strength: The compressive strength of Examples 17-20 is increased from 450MPa to 520MPa, which is due to the design of the reinforcement ribs of each layer structure and the reasonable material selection and processing technology. For example, the reinforcement layer is subjected to hot rolling, quenching and aging treatment, which improves the strength and hardness of the material and enhances the compressive resistance of the manifold. However, in Comparative Examples 2-4, the compressive strength is greatly reduced due to the lack of each layer structure. In Comparative Example 4, the compressive strength is only 350MPa due to the lack of the reinforcement layer, which shows that the reinforcement layer plays a key supporting role in compression. The order of Comparative Example 5 is changed, and the compressive strength decreases, which shows that the order of each layer structure affects the transfer and distribution of force, and thus affects the compressive strength. Although Comparative Examples 1 and 6 have complete structures, the compressive strength is lower than that of the examples due to the lack of nano-coating or oxide film treatment, indicating that the surface treatment not only affects the surface properties, but also affects the overall compressive strength by affecting the interface bonding and structural integrity.

[0242] Torsional strength: The torsional strength of Examples 17-20 is increased from 200 N·m to 250 N·m. The structural design of the main reinforcement ribs, secondary reinforcement ribs and reinforcement rings enhances the torsional resistance of the manifold. The performance optimization of each layer of material also contributes to the improvement of torsional strength. However, in Comparative Examples 2-4, the torsional strength is significantly reduced due to the lack of each layer of structure. In Comparative Example 4, the torsional strength is the lowest, only 150 N·m, which shows that the reinforcement layer is crucial in resisting torque. In Comparative Example 5, the order is changed and the torsional strength decreases, which shows that the structural order has an impact on torque transmission and resistance. Due to the lack of nano-coating or oxide film treatment, the torsional strength of Comparative Examples 1 and 6 is lower than that of the examples, indicating that surface treatment has an important influence on the torsional performance of the manifold, which may be achieved by affecting the microstructure and interface bonding strength of the material.

[0243] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Within the scope of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0244] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-strength aluminum alloy header, characterized in that: The collecting pipe is a four-layer composite structure, which is composed of a corrosion-resistant layer, a buffer layer, a reinforcement layer and a wear-resistant layer from the inside to the outside. The thickness ratio of the corrosion-resistant layer, buffer layer, reinforcement layer and wear-resistant layer is 1.5-2mm: 1-1.5mm: 1.5-2mm: 0.8-1.2mm; A nano coating is deposited on the outer surface of the wear-resistant layer; The material of the corrosion-resistant layer is silicon-aluminum alloy; The material of the buffer layer is aluminum alloy; The material of the reinforcement layer is high-strength aluminum alloy; The material of the wear-resistant layer is high-hardness aluminum alloy; The nano coating is an aluminum alloy composite material reinforced by carbon nanotubes.

2. The high-strength aluminum alloy header according to claim 1, characterized in that: The preparation process of the silicon-aluminum alloy in the corrosion-resistant layer is as follows: Step A1. Place an aluminum ingot in a melting furnace and smelt it at 720-750°C until the aluminum ingot is completely melted into a liquid state. Add industrial pure silicon and stir at 100-150 rpm for 20-25 minutes. Then add additive 1 and stir at 120-150 rpm for 15-20 minutes to obtain a mixed solution 1. Step A2. The mixed gas 1 is introduced into the mixed liquid 1 and refined at a speed of 100-120 rpm for 20-30 min. After the refining is completed, the mixture is allowed to stand for 7-10 min to obtain a refined liquid 1. The refined liquid 1 is cast into a mold preheated to 200-250°C for casting. During the casting process, the casting speed is controlled at 3-5 kg / s. After the casting is completed, the mold is cooled at a cooling rate of 10-15°C / s. After the alloy is completely solidified, it is removed from the mold to obtain a preliminarily formed silicon-aluminum alloy billet 1; Step A3. The silicon-aluminum alloy billet 1 is hot rolled, the billet is heated to 450-500°C, and rolled on a hot rolling mill with 3-5 rolling passes and a reduction of 10%-15% for each rolling. After hot rolling, the billet is cold rolled with 2-3 cold rolling passes and a reduction of 5%-8% for each cold rolling. The cold-rolled silicon-aluminum alloy is cut, stamped, and processed to form a corrosion-resistant layer that meets the size specifications.

3. The high-strength aluminum alloy header according to claim 2, characterized in that: The purity of the aluminum ingot in step A1 is ≥99.5%; The mass ratio of the aluminum ingot, industrial pure silicon and additive 1 in step A1 is 85-92:6-12:0.6-2.8; The additive 1 in step A1 is a mixture of magnesium and manganese in a mass ratio of 0.5-2:0.1-0.8; The mixed gas 1 in step A2 is obtained by mixing argon and chlorine in a volume ratio of 5:1; The flow rate of the mixed gas 1 in step A2 is controlled to be 0.5-1 L / min.

4. The high-strength aluminum alloy header according to claim 1, characterized in that: The preparation process of the aluminum alloy in the buffer layer is as follows: Step B1. Place the aluminum ingot in a resistance melting furnace and heat it to 680-720°C to completely melt it into a liquid state. Add industrial pure magnesium and stir at 120-180 rpm for 20-30 minutes. Add additive 2 and flux 1 and stir at 120-180 rpm for 15-20 minutes to obtain mixed solution 2. Step B2. The mixed gas 2 is introduced into the mixed liquid 2 and refined at a speed of 100-150 rpm for 25-35 min. After the refining is completed, the mixture is allowed to stand for 8-12 min to obtain a refined liquid 2. The refined liquid 2 is cast into a mold preheated to 230-280°C at a casting speed of 4-6 kg / s. The mold is cooled at a cooling rate of 8-12°C / s to obtain an aluminum alloy billet 2; Step B3: Forging the aluminum alloy billet 2, heating the billet to 480-530° C., forging it 3-5 times on a forging device, controlling the forging ratio at 3-5, and forming a buffer layer that meets the specifications after forging.

5. The high-strength aluminum alloy header according to claim 4, characterized in that: The purity of the aluminum ingot in step B1 is ≥99.8%; The purity of the industrial pure magnesium in step B1 is ≥99.5%; The mass ratio of the aluminum ingot, industrial pure magnesium, additive 2 and flux 1 in step B1 is 90-95:3-6:0.1-0.5:0.3-1; The additive 2 in step B1 is a mixture of titanium and boron in a mass ratio of 0.05-0.3:0.05-0.2; The flux 1 in step B1 is a mixture of potassium chloride and sodium chloride in a mass ratio of 1-1.2:1.5-3; The mixed gas 2 in step B2 is obtained by mixing argon and chlorine in a volume ratio of 6:1; The gas flow rate of the mixed gas 2 in step B2 is 0.6-1.2 L / min.

6. The high-strength aluminum alloy header according to claim 1, characterized in that: The preparation process of the high-strength aluminum alloy in the reinforcement layer is as follows: Step C1. Place the aluminum ingot in an electromagnetic induction melting furnace and heat it to 730-760°C to completely melt it into a liquid state. Then, add industrial pure copper and industrial pure magnesium, stir at a stirring frequency of 150-200 Hz for 30-40 minutes, then add additive 3, and continue stirring at a stirring frequency of 150-200 Hz for 25-30 minutes to obtain a mixed solution 3. Step C2. Mixed gas 3 is introduced into the mixed solution 3, and the mixture is refined at a stirring frequency of 150-200 Hz for 30-40 minutes. Then, flux 2 is added, stirring is continued for 10-15 minutes, and then the mixture is allowed to stand for 10-15 minutes. Then, a sodium salt modifier is added, stirring is continued at a stirring frequency of 150-200 Hz for 10-12 minutes, and then the mixture is kept warm for 5-10 minutes to obtain an aluminum alloy billet 3; Step C3. Cast the aluminum alloy billet 3 into a mold preheated to 250-300°C at a casting rate of 5-7 kg / s. Cool the mold at a cooling rate of 12-18°C / s. After the alloy is completely solidified, remove it from the mold, heat the removed billet to 500-550°C, and roll it on a hot rolling mill 3-5 times. The total rolling deformation is controlled at 60%-80%. After hot rolling, heat it to 530-550°C and keep it for 2-3 hours. Water-cooled quenching is performed, and the quenched alloy is then heated to 150-180°C and kept warm for 6-8 hours. Finally, the aluminum alloy is machined according to the design size of the collector to obtain a reinforcement layer.

7. The high-strength aluminum alloy header according to claim 6, characterized in that: The purity of the aluminum ingot in step C1 is ≥99.9%; The purity of the industrial pure copper in step C1 is ≥99.6%; The purity of the industrial pure magnesium in step C1 is ≥99.5%; The mass ratio of the aluminum ingot, industrial pure copper, industrial pure magnesium, additive 3, flux 2 and sodium salt modifier is 80-90:4-8:2-5:0.1-0.5:0.5-1:0.1-0.3; The additive 3 in step C1 is a mixture of zirconium and vanadium in a mass ratio of 0.05-0.3:0.05-0.2; The flux 2 in step C2 is a mixture of potassium chloride and sodium chloride in a mass ratio of 0.1-0.2:0.4-0.8; The mixed gas 3 in step C2 is obtained by mixing argon and chlorine in a volume ratio of 8:1; The gas flow rate of the mixed gas 3 in step C2 is 0.8-1.5 L / min.

8. The high-strength aluminum alloy header according to claim 1, characterized in that: The preparation process of the high hardness aluminum alloy in the wear-resistant layer is as follows: Step D1. Place the aluminum ingot in an electromagnetic induction melting furnace and heat it to 750-780°C to completely melt it into a liquid state. Argon gas is introduced into the furnace, and silicon carbide particles are added. Stir at a stirring frequency of 200-250 Hz for 40-50 minutes. Then, industrial pure copper and additive 4 are added, and stirring is continued for 20-25 minutes to obtain a mixed solution 4. Step D2. Adding mixed gas 4 to the mixed solution 4 and refining for 35-50 minutes, then adding flux 3, stirring evenly, and letting it stand for 12-18 minutes. Then, adding a sodium salt modifier, stirring evenly, and holding the mixture for 6-10 minutes to obtain refined solution 4. The refined solution 4 is cast into a mold preheated to 280-320°C at a casting speed of 6-8 kg / s. After casting, the mold is cooled at a cooling rate of 15-20°C / s to obtain alloy billet 4; Step D3. Heat the alloy billet 4 to 520-560°C, extrude it on a hot extruder with an extrusion ratio controlled at 10-15, then heat the alloy to 540-560°C and keep it warm for 2.5-3.5 hours, then quench it in cold water, heat the quenched alloy to 160-190°C and keep it warm for 7-9 hours, and finally machine the alloy according to the size of the collector to obtain a wear-resistant layer.

9. The high-strength aluminum alloy header according to claim 8, characterized in that: The mass ratio of the aluminum ingot, silicon carbide particles, industrial pure copper, additive 4, flux 3 and sodium salt modifier is 70-85:10-20:3-8:0.1-1:0.6-1.2:0.15-0.35; The purity of the aluminum ingot in step D1 is ≥99.9%; The purity of the silicon carbide particles in step D1 is ≥99.7%; The purity of the pure copper in step D1 is ≥99.5%; The additive 4 in step D1 is a mixture of yttrium and boron in a mass ratio of 0.05-0.5:0.05-0.5; In step D2, the flux 3 is potassium chloride, sodium chloride and calcium fluoride in a mass ratio of 25-40:40-60:5-15; The mixed gas 4 in step D2 is obtained by mixing argon and chlorine in a volume ratio of 10:1; The gas flow rate of the mixed gas 4 in step D2 is 1-1.8 L / min.

10. The high-strength aluminum alloy header according to claim 1, characterized in that: The preparation process of the nano coating is as follows: Step E1. Add sodium phosphate, sodium hydroxide and sodium silicate to deionized water and stir to obtain an electrolyte; Step E2. Immerse the surface of the wear-resistant layer of the header in a sodium hydroxide solution at a temperature of 60-80°C and a concentration of 50-80g / L for 10-15min, and then soak in a nitric acid solution at a temperature of 40-60°C and a concentration of 30-50g / L for 5-10min; Step E3. Place the treated wear-resistant layer of the collector into an electrolytic cell filled with electrolyte, use a stainless steel plate as the cathode, and conduct electricity at a voltage of 250-350V at a current of 8-12A / dm 2 The plasma electrolytic oxidation treatment is carried out at a current density of 1000 nm and 20-30°C for 50-70 minutes to form an oxide film with a thickness of 20-30 μm; Step E4. The carbon nanotubes were placed in a mixed acid solution and ultrasonically treated at 60-80°C for 2-3 hours. The carbon nanotubes were then repeatedly rinsed with deionized water until neutral and vacuum dried at 80-100°C for 2-3 hours. The manifold was fixed on the sample stage in the reactor, and the distance between the sample stage and the gas nozzle was adjusted to 10-15 cm. The manifold was placed in the reactor and argon was introduced as a carrier gas. The reactor was then heated to 500-600°C and the mixed gas 5 was introduced. The deposition time was 2-3 hours at 10-20 Pa to obtain a nanocoating with a thickness of 3-5 μm. The mass ratio of sodium phosphate, sodium hydroxide, sodium silicate and deionized water in step E1 is 5-10:3-7:5-10:73-87; The mixed acid solution in step E4 is obtained by mixing concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:3; The flow rate of argon gas in step E4 is controlled at 50-100 mL / min; In step E4, the concentration of carbon nanotubes in the mixed gas 5 is 0.1-0.3 g / L, and the concentration of the aluminum alloy precursor is 1-3 mol / L; The mass ratio of trimethylaluminum, tetraethylsilane and magnesium acetylacetonate in the aluminum alloy precursor is 40-50:30-40:10-20.