Lightweight aluminum alloy with excellent wear resistance and preparation method thereof

Abstract

The invention belongs to the technical field of light-weight aluminum alloy materials, and particularly relates to a light-weight aluminum alloy with excellent wear resistance and a preparation method of the light-weight aluminum alloy. According to the method, on the basis of aluminum-magnesium-silicon alloy, copper, manganese, titanium, nickel, zinc and cerium elements are added to prepare an aluminum alloy ingot sample, and then the lightweight aluminum alloy product is obtained through the steps of surface impact treatment and surface cleaning. A refining agent adopts carnallite to replace chlorine salt, the refining cost is saved, carbon monoxide released by oxalate at a high temperature reacts with active hydrogen, then the active hydrogen of aluminum alloy melt at a high temperature is removed, chlorine is reduced, surface impact treatment can increase roughness, improve film adhesion, refine grains and improve hardness and strength, and the service life of the aluminum alloy melt is prolonged. And long-acting cleaning and corrosion resistance of the surface can be achieved through surface cleaning, so that the light-weight aluminum alloy product has excellent tensile strength, hardness and wear resistance, and the corrosion resistance is good.

Description

Technical Field

[0001] The present invention belongs to the technical field of lightweight aluminum alloy materials, and specifically relates to a lightweight aluminum alloy with excellent wear resistance and a preparation method thereof. Background Art

[0002] Aluminum alloy refers to aluminum with copper, magnesium, silicon, manganese and other elements added to it to improve its strength or overall performance. Aluminum alloy is the preferred alloy for the automotive, aerospace, shipbuilding and other industries due to its high specific strength (density is about 1 / 3 of traditional steel), good corrosion resistance and thermal conductivity. Most modern sports equipment is made of aluminum alloy. Due to the easy processing of aluminum alloy, it is relatively convenient to manufacture sports equipment of various shapes and sizes. The high specific strength of aluminum alloy can reduce the amount of material used while ensuring the performance of the equipment, which helps to reduce energy consumption and emissions in the production process. However, due to the shortcomings of aluminum alloy materials such as low hardness and poor wear resistance, the phenomenon of sports equipment failure caused by aluminum alloy wear is easy to occur.

[0003] The Chinese invention patent with publication number CN116287903B discloses a lightweight, corrosion-resistant aluminum alloy and its preparation method, which belongs to the technical field of lightweight aluminum alloy materials. The alloy of the present invention is prepared by raw materials containing the following mass percentages: 2-4% zinc, 1-2% nickel, 0.5-1% copper, 0.3-0.5% titanium, 0.3-0.5% chromium, 0.5-0.8% rare earth elements, and the balance is aluminum. The patent further performs surface treatment after casting, and uses a gradient concentration of lanthanum nitrate passivation solution to treat the surface of the aluminum alloy to form a dense oxide film, and the mechanical properties and corrosion resistance of the obtained aluminum alloy are greatly improved. A lightweight aluminum alloy profile for automobiles provided by the Chinese invention patent with publication number CN117987684B is prepared from raw materials in the following mass percentages: 2.4-2.7% cathode copper, 2.9-3.2% magnesium ingots, 10.1-10.5% zinc ingots, 1.4-1.7% aluminum-zirconium alloy, 2.7-2.9% reinforcing particles, and the rest are aluminum ingots. The aluminum alloy profile prepared by this patent has light weight, high strength and toughness, and excellent corrosion resistance. However, the prior art still has no improvements on the elemental composition of the aluminum alloy and the refining and surface treatment steps in the preparation process to further improve its lightweight, tensile strength, hardness and wear resistance. Summary of the invention

[0004] The object of the present invention is to provide a lightweight aluminum alloy with excellent wear resistance and a preparation method thereof, so as to solve the technical problem that the prior art has not improved the elemental composition of the aluminum alloy and the refining and surface treatment steps in the preparation process to further improve its lightweight, tensile strength, hardness and wear resistance.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A lightweight aluminum alloy with excellent wear resistance comprises the following elements in percentage by mass: 0.1-0.3wt% zinc, 0.5-1wt% copper, 0.5-0.7wt% silicon, 0.8-1.2wt% magnesium, 0.1-0.3wt% titanium, 0.05-0.2wt% cerium, 0.1-0.2wt% manganese, 0.1-0.3wt% nickel, less than 0.03wt% of impurity element iron and less than 0.005wt% of other impurity elements, and the balance is aluminum.

[0007] Preferably, the lightweight aluminum alloy is prepared from the following raw materials: pure aluminum, pure magnesium, pure zinc, Al-10Si aluminum-silicon master alloy, Al-10Ni aluminum-nickel master alloy, Al-50Cu aluminum-copper master alloy, Al-10Ce aluminum-cerium master alloy, Al-10Mn aluminum-manganese master alloy and Al-5Ti aluminum-titanium master alloy.

[0008] The present invention also provides a method for preparing a lightweight aluminum alloy with excellent wear resistance, comprising the following steps:

[0009] S1. Preheating: preheat the raw materials to 400-450°C and the crucible to 500-600°C according to mass parts;

[0010] S2, smelting: add pure aluminum into a crucible, heat to 720-780°C, until pure aluminum is completely melted, add aluminum silicon, aluminum nickel, aluminum copper, aluminum manganese and aluminum titanium master alloy in a stirring state, then add pure magnesium and pure zinc, stir until all are melted, finally cool to 720-730°C, add aluminum cerium master alloy, and stand for 5-10 minutes for modification;

[0011] S3, refining: after smelting, the crucible temperature is adjusted to 740-760°C, and the refining agent is added to keep the temperature for 5-10 minutes, and then the pulse rotary blowing process is used to refine and remove the surface scum. The pulse rotary blowing parameters are set to an air flow rate of 5-8 L / min, a stirring speed of 50-100 rpm, and a stirring time of 5-10 minutes;

[0012] S4, casting and molding: immediately pouring the aluminum alloy melt after refining into a mold for casting and molding to obtain an aluminum alloy ingot sample;

[0013] S5. Surface treatment: Fix the aluminum alloy ingot sample, and use an air compressor to spray the abrasive to perform surface impact treatment on the aluminum alloy ingot sample;

[0014] S6. Surface cleaning: After the surface treatment, the aluminum alloy ingot sample is placed in a cleaning solution for ultrasonic treatment for 5 to 10 minutes. After cleaning, it is dried to obtain a lightweight aluminum alloy.

[0015] Preferably, before the preheat treatment of the crucible in S1, the crucible is further cleaned with deionized water, dried at 200-300°C for 1-2 hours, coated with a protective liquid, and then dried at 200-300°C for 1-2 hours.

[0016] Preferably, the protective solution is prepared by adding 10 to 15 parts of sodium silicate and 7 to 10 parts of zinc oxide to 100 to 120 parts of deionized water in parts by weight.

[0017] Preferably, the heating temperature rise rate in S2 is 5±0.2°C / min, and the cooling rate is 2.5±0.2°C / min.

[0018] Preferably, the heating temperature rise rate in S3 is 5±0.2°C / min.

[0019] Preferably, the aluminum alloy melt in S4 is injected into a mold at a temperature of 200 to 300° C. at a speed of 2±0.5 m / s and cooled naturally.

[0020] Preferably, the aluminum alloy ingot sample in S5 needs to be ground and polished to a mirror finish before surface treatment.

[0021] Preferably, the parameters of the surface treatment in S5 are set as follows: the angle between the spray direction and the normal line of the sample surface is less than 60°, the spray pressure is 0.5-0.6 MPa, and the nozzle distance is 70-100 mm.

[0022] Preferably, the cleaning liquid in S6 is any one of anhydrous ethanol, anhydrous methanol and acetone solution.

[0023] Preferably, the method for preparing the refining agent in S3 comprises the following steps:

[0024] S11, placing cryolite, potassium cryolite and aluminum fluoride in a crucible, heating to 200-300°C for dehydration for 3-4 hours, then heating to 700-750°C for melting and heat preservation for 10-20 minutes, stirring the melt continuously during the heat preservation period, pouring and solidifying the melt after the heat preservation, and crushing and grinding to a particle size of less than 1 mm after cooling to obtain a crude fluoride salt complex;

[0025] S12. Evenly mix the crude fluoride salt complex, potassium oxalate and carnallite, and obtain a refining agent after drying.

[0026] Preferably, the raw materials used in the preparation process of the refining agent are 10-15 parts of cryolite, 10-15 parts of potassium cryolite, 10-15 parts of aluminum fluoride, 5-30 parts of potassium oxalate and 40-50 parts of carnallite in parts by mass.

[0027] Preferably, the carnallites are dehydrated low-sodium carnallites, with a sodium chloride content of less than 5% and a magnesium chloride content of less than 40%.

[0028] Preferably, the method for preparing the abrasive in S5 comprises the following steps:

[0029] S21, placing the hard grinding balls in a solvent for ultrasonic cleaning for 10 to 15 minutes, and drying after cleaning;

[0030] S22, after the hard grinding ball is sprayed with the grinding liquid for absorption, it is put into the grinding powder and stirred evenly, so that the grinding powder is evenly absorbed on the surface of the hard grinding ball to obtain the grinding material.

[0031] Preferably, the hard grinding balls in S21 are any one of hard glass balls, ceramic balls and steel balls.

[0032] Preferably, the solvent in S21 is any one of anhydrous ethanol, anhydrous methanol and acetone solution.

[0033] Preferably, the adsorption grinding liquid in S22 is composed of a mixture of 15 parts of potassium sorbate, 10 parts of sodium silicate, 15 parts of triethanolamine and 60 parts of deionized water, in parts by mass.

[0034] Preferably, the ground powder in S22 is composed of 70-80 parts of titanium powder, 5-6 parts of cerium oxide powder and 14-25 parts of aluminum oxide powder, in parts by mass.

[0035] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0036] 1. The present invention is based on aluminum-magnesium-silicon alloy, and copper, manganese, titanium, nickel, zinc and cerium elements are added to prepare aluminum alloy ingot samples, and then a surface impact treatment and surface cleaning step are performed to obtain a lightweight aluminum alloy product. Surface impact treatment can increase roughness, improve film adhesion, refine grains and improve hardness and strength, and surface cleaning can achieve long-term cleaning and corrosion resistance of the surface, so that the lightweight aluminum alloy product has excellent tensile strength, hardness and wear resistance, and good corrosion resistance.

[0037] 2. The addition of copper element in the present invention enhances the solid solution strengthening and aging strengthening effects of the aluminum alloy. The addition of manganese, titanium and cerium elements can increase the recrystallization temperature of the aluminum alloy and can significantly refine the recrystallized grains, thereby improving the tensile strength and hardness of the alloy. The added manganese element can also dissolve part of the impurity iron, thereby changing the lamellar or needle-like structure formed by iron in the aluminum alloy into a fine crystalline structure. The added nickel element can form a peritectic reaction with the iron element, thereby jointly reducing the harmful effects of iron.

[0038] 3. The refining agent of the present invention adopts carnallite instead of chloride salt, which saves refining cost. The carbon monoxide released by oxalate at high temperature reacts with active hydrogen, thereby removing the active hydrogen in the high-temperature aluminum alloy melt and reducing the generation of chlorine. The fluoride salt complex prepared by cryolite, potassium cryolite and aluminum fluoride in a certain ratio can dissolve and adsorb oxide impurities in the aluminum alloy melt and then float them to play a slag removal role.

[0039] 4. In the surface impact treatment step of the present invention, the abrasive impacts the aluminum alloy surface at high speed, so that the residual stress field is introduced into the surface and the grain is refined. In addition, the abrasive forms a titanium-aluminum coating with the aluminum alloy substrate under the conditions of high-speed impact and high-temperature friction. The cerium oxide in the abrasive promotes the bonding of the titanium-aluminum coating, thereby significantly improving the mechanical properties and wear resistance of the aluminum alloy. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Example 1. A lightweight aluminum alloy with excellent wear resistance in this embodiment contains the following elements in percentage by mass: 0.1wt% zinc, 0.9wt% copper, 0.7wt% silicon, 1.2wt% magnesium, 0.2wt% titanium, 0.1wt% cerium, 0.15wt% manganese, 0.1wt% nickel, less than 0.03wt% of impurity element iron and less than 0.005wt% of other impurity elements, and the balance is aluminum.

[0042] This embodiment also provides a method for preparing a lightweight aluminum alloy with excellent wear resistance, comprising the following steps:

[0043] S1, preheating treatment: according to the proportion of each component of the aluminum alloy, 865 parts of pure aluminum, 1.5 parts of pure zinc, 12.5 parts of pure magnesium, 73.5 parts of Al-10Si aluminum silicon master alloy, 10.5 parts of Al-10Ni aluminum nickel master alloy, 19 parts of Al-50Cu aluminum copper master alloy, 10.5 parts of Al-10Ce aluminum cerium master alloy, 15.8 parts of Al-10Mn aluminum manganese master alloy and 42 parts of Al-5Ti aluminum titanium master alloy are weighed by mass, the raw materials are preheated to 400°C, and the crucible is preheated to 500°C. Before the preheating treatment of the crucible, the crucible is also washed with deionized water and dried at 200°C for 2h. According to parts by weight, 10 parts of sodium silicate and 7 parts of zinc oxide are added to 100 parts of deionized water to prepare a protective liquid. After the crucible is coated with the protective liquid, it is dried at 300°C for 1h;

[0044] S2, smelting: add pure aluminum into a crucible, heat it to 750°C at a heating rate of 5°C / min, and after the pure aluminum is completely melted, add aluminum silicon, aluminum nickel, aluminum copper, aluminum manganese and aluminum titanium master alloy in a stirring state, then add pure magnesium and pure zinc, stir until all are melted, cool down at a rate of 2.5°C / min, finally cool to 720°C, add aluminum cerium master alloy, and let stand for 5 minutes for modification;

[0045] S3, refining: after smelting, the crucible temperature is adjusted to 750°C, the heating rate is 5°C / min, the refining agent is added and kept warm for 5 minutes, and then the pulse rotary blowing process is used to refine and remove the surface scum, and the pulse rotary blowing parameters are set to air flow rate 5L / min, stirring speed 80rpm, stirring time 10min;

[0046] S4, casting and molding: the aluminum alloy melt after refining is injected into a mold at a temperature of 250° C. at a speed of 2 m / s, and cooled naturally to obtain an aluminum alloy ingot sample;

[0047] S5. Surface treatment: Fix the aluminum alloy ingot sample, use an air compressor to spray the abrasive to perform surface impact treatment on the aluminum alloy ingot sample, and set the parameters of the surface treatment such that the angle between the spray direction and the normal line of the sample surface is less than 60°, the spray pressure is 0.5 MPa, and the nozzle distance is 80 mm;

[0048] S6. Surface cleaning: After the surface treatment, the aluminum alloy ingot sample is placed in anhydrous ethanol for ultrasonic treatment for 5 minutes. After cleaning, it is dried to obtain a lightweight aluminum alloy.

[0049] The method for preparing the refining agent in S3 comprises the following steps:

[0050] S11, put 10 parts of cryolite, 10 parts of potassium cryolite and 10 parts of aluminum fluoride into a crucible, heat to 300°C for dehydration for 3 hours, then heat to 750°C for melting and heat preservation for 20 minutes, stir the melt continuously during the heat preservation period, pour and solidify the melt after the heat preservation, and grind it to a particle size of less than 1 mm after cooling to obtain 30 parts of a crude fluoride salt complex;

[0051] S12. 30 parts of crude fluoride complex, 30 parts of potassium oxalate and 40 parts of carnallites are mixed evenly, and dried to obtain a refining agent, wherein the carnallites are dehydrated low-sodium carnallites, the sodium chloride content is less than 5%, and the magnesium chloride content is 32.5%.

[0052] The method for preparing the abrasive in S5 comprises the following steps:

[0053] S21, placing the ceramic ball in anhydrous ethanol for ultrasonic cleaning for 15 minutes, and drying after cleaning;

[0054] S22. According to parts by mass, 15 parts of potassium sorbate, 10 parts of sodium silicate, 15 parts of triethanolamine and 60 parts of deionized water are mixed to form an adsorption grinding liquid, and 70 parts of titanium powder, 5 parts of cerium oxide powder and 25 parts of aluminum oxide powder are mixed to form a grinding powder. After spraying the adsorption grinding liquid on the ceramic ball, put it into the grinding powder and stir evenly to make the grinding powder evenly adsorbed on the surface of the ceramic ball to obtain the abrasive.

[0055] Example 2. A lightweight aluminum alloy with excellent wear resistance in this embodiment contains the following elements in percentage by mass: 0.1wt% zinc, 0.8wt% copper, 0.6wt% silicon, 1.0wt% magnesium, 0.1wt% titanium, 0.1wt% cerium, 0.2wt% manganese, 0.15wt% nickel, less than 0.03wt% of impurity element iron and less than 0.005wt% of other impurity elements, and the balance is aluminum.

[0056] This embodiment also provides a method for preparing a lightweight aluminum alloy with excellent wear resistance, comprising the following steps:

[0057] S1, preheating treatment: according to the proportion of each component of the aluminum alloy, 900.5 parts of pure aluminum, 1.5 parts of pure zinc, 10.5 parts of pure magnesium, 63 parts of Al-10Si aluminum silicon master alloy, 15.8 parts of Al-10Ni aluminum nickel master alloy, 16.8 parts of Al-50Cu aluminum copper master alloy, 10.5 parts of Al-10Ce aluminum cerium master alloy, 21 parts of Al-10Mn aluminum manganese master alloy and 21 parts of Al-5Ti aluminum titanium master alloy are weighed by mass, the raw materials are preheated to 400°C, and the crucible is preheated to 500°C. Before the preheating treatment of the crucible, the crucible is also washed with deionized water and dried at 200°C for 2h. According to parts by weight, 10 parts of sodium silicate and 7 parts of zinc oxide are added to 100 parts of deionized water to prepare a protective liquid. After the crucible is coated with the protective liquid, it is dried at 300°C for 1h;

[0058] S2, smelting: add pure aluminum into a crucible, heat it to 760°C at a heating rate of 5.2°C / min, and after the pure aluminum is completely melted, add aluminum silicon, aluminum nickel, aluminum copper, aluminum manganese and aluminum titanium master alloy in a stirring state, then add pure magnesium and pure zinc, stir until all are melted, cool down at a rate of 2.3°C / min, finally cool to 730°C, add aluminum cerium master alloy, and let stand for 5 minutes for modification;

[0059] S3, refining: after smelting, the crucible temperature is adjusted to 750°C, the heating rate is 5.2°C / min, and the refining agent is added and kept warm for 10 minutes, and then the pulse rotary blowing process is used to refine and remove the surface scum. The pulse rotary blowing parameters are set to an air flow rate of 6L / min, a stirring speed of 90rpm, and a stirring time of 6min;

[0060] S4, casting and molding: the aluminum alloy melt after refining is injected into a mold at a temperature of 300° C. at a speed of 1.5 m / s, and cooled naturally to obtain an aluminum alloy ingot sample;

[0061] S5. Surface treatment: Fix the aluminum alloy ingot sample, use an air compressor to spray the abrasive to perform surface impact treatment on the aluminum alloy ingot sample, and set the parameters of the surface treatment such that the angle between the spray direction and the normal line of the sample surface is less than 60°, the spray pressure is 0.6 MPa, and the nozzle distance is 90 mm;

[0062] S6. Surface cleaning: After the surface treatment, the aluminum alloy ingot sample is placed in a 12.5wt% acetone solution for ultrasonic treatment for 5 minutes, and then dried to obtain a lightweight aluminum alloy.

[0063] The refining agent of this embodiment is made of the same material as that of the refining agent of Embodiment 1.

[0064] The difference between the abrasive of this embodiment and that of embodiment 1 is that the hard abrasive balls are GCr15 steel balls, and the abrasive powder is composed of 80 parts of titanium powder, 6 parts of cerium oxide powder and 14 parts of aluminum oxide powder.

[0065] Example 3. A lightweight aluminum alloy with excellent wear resistance in this embodiment contains the following elements in percentage by mass: 0.2wt% zinc, 0.5wt% copper, 0.5wt% silicon, 0.8wt% magnesium, 0.2wt% titanium, 0.15wt% cerium, 0.2wt% manganese, 0.3wt% nickel, less than 0.03wt% of impurity element iron and less than 0.005wt% of other impurity elements, and the balance is aluminum.

[0066] This embodiment also provides a method for preparing a lightweight aluminum alloy with excellent wear resistance, comprising the following steps:

[0067] S1, preheating treatment: according to the proportion of each component of the aluminum alloy, 866 parts of pure aluminum, 2.5 parts of pure zinc, 8.5 parts of pure magnesium, 52.5 parts of Al-10Si aluminum silicon master alloy, 31.5 parts of Al-10Ni aluminum nickel master alloy, 10.5 parts of Al-50Cu aluminum copper master alloy, 15.8 parts of Al-10Ce aluminum cerium master alloy, 21 parts of Al-10Mn aluminum manganese master alloy and 42 parts of Al-5Ti aluminum titanium master alloy are weighed by mass, the raw materials are preheated to 450°C, and the crucible is preheated to 500°C. Before the preheating treatment of the crucible, the crucible is also washed with deionized water and dried at 200°C for 2h. According to parts by weight, 10 parts of sodium silicate and 7 parts of zinc oxide are added to 120 parts of deionized water to prepare a protective liquid. After the crucible is coated with the protective liquid, it is dried at 300°C for 2h.

[0068] S2, smelting: add pure aluminum into a crucible, heat at a heating rate of 4.8°C / min, heat to 740°C, until the pure aluminum is completely melted, add aluminum silicon, aluminum nickel, aluminum copper, aluminum manganese and aluminum titanium master alloy in a stirring state, then add pure magnesium and pure zinc, stir until all are melted, cool at a cooling rate of 2.3°C / min, finally cool to 730°C, add aluminum cerium master alloy, and stand for 10 minutes for modification;

[0069] S3, refining: after the smelting is completed, the crucible temperature is adjusted to 760°C, the heating rate is 5°C / min, and the refining agent is added and kept warm for 6 minutes, and then the pulse rotary blowing process is used for refining and surface scum is removed. The pulse rotary blowing parameters are set to an air flow rate of 5L / min, a stirring speed of 50rpm, and a stirring time of 10min;

[0070] S4, casting and molding: the aluminum alloy melt after refining is injected into a mold at a temperature of 250° C. at a speed of 2.5 m / s, and cooled naturally to obtain an aluminum alloy ingot sample;

[0071] S5. Surface treatment: Fix the aluminum alloy ingot sample, use an air compressor to spray the abrasive to perform surface impact treatment on the aluminum alloy ingot sample, and set the parameters of the surface treatment such that the angle between the spray direction and the normal line of the sample surface is less than 60°, the spray pressure is 0.5 MPa, and the nozzle distance is 70 mm;

[0072] S6. Surface cleaning: After the surface treatment, the aluminum alloy ingot sample is placed in anhydrous methanol for ultrasonic treatment for 10 minutes. After cleaning, it is dried to obtain a lightweight aluminum alloy.

[0073] The refining agent of this embodiment is different from that of Embodiment 1 in that the proportion of the various substances in the refining agent is changed to 40 parts of crude fluoride salt complex, 10 parts of potassium oxalate and 50 parts of carnallite.

[0074] The abrasive of this embodiment is made of the same material as that of the abrasive of embodiment 1.

[0075] Example 4. A lightweight aluminum alloy with excellent wear resistance in this embodiment contains the following elements in percentage by mass: 0.1wt% zinc, 0.8wt% copper, 0.7wt% silicon, 1.2wt% magnesium, 0.15wt% titanium, 0.15wt% cerium, 0.2wt% manganese, 0.2wt% nickel, less than 0.03wt% of impurity element iron and less than 0.005wt% of other impurity elements, and the balance is aluminum.

[0076] This embodiment also provides a method for preparing a lightweight aluminum alloy with excellent wear resistance, comprising the following steps:

[0077] S1, preheating treatment: according to the proportion of each component of the aluminum alloy, 865 parts of pure aluminum, 1.5 parts of pure zinc, 12.5 parts of pure magnesium, 73.5 parts of Al-10Si aluminum silicon master alloy, 10.5 parts of Al-10Ni aluminum nickel master alloy, 16.8 parts of Al-50Cu aluminum copper master alloy, 10.5 parts of Al-10Ce aluminum cerium master alloy, 15.8 parts of Al-10Mn aluminum manganese master alloy and 42 parts of Al-5Ti aluminum titanium master alloy are weighed by mass, the raw materials are preheated to 400°C, and the crucible is preheated to 500°C. Before the preheating treatment of the crucible, the crucible is also washed with deionized water and dried at 200°C for 2h. According to parts by weight, 10 parts of sodium silicate and 7 parts of zinc oxide are added to 100 parts of deionized water to prepare a protective liquid. After the crucible is coated with the protective liquid, it is dried at 300°C for 1h;

[0078] S2, smelting: add pure aluminum into a crucible, heat it to 750°C at a heating rate of 5°C / min, and after the pure aluminum is completely melted, add aluminum silicon, aluminum nickel, aluminum copper, aluminum manganese and aluminum titanium master alloy in a stirring state, then add pure magnesium and pure zinc, stir until all are melted, cool down at a rate of 2.5°C / min, finally cool to 720°C, add aluminum cerium master alloy, and let stand for 5 minutes for modification;

[0079] S3, refining: after smelting, the crucible temperature is adjusted to 750°C, the heating rate is 5°C / min, the refining agent is added and kept warm for 5 minutes, and then the pulse rotary blowing process is used to refine and remove the surface scum, and the pulse rotary blowing parameters are set to air flow rate 5L / min, stirring speed 50rpm, stirring time 5min;

[0080] S4, casting and molding: the aluminum alloy melt after refining is injected into a mold at a temperature of 300° C. at a speed of 2 m / s, and cooled naturally to obtain an aluminum alloy ingot sample;

[0081] S5. Surface treatment: Fix the aluminum alloy ingot sample, use an air compressor to spray the abrasive to perform surface impact treatment on the aluminum alloy ingot sample, and set the parameters of the surface treatment such that the angle between the spray direction and the normal line of the sample surface is less than 60°, the spray pressure is 0.6 MPa, and the nozzle distance is 100 mm;

[0082] S6. Surface cleaning: After the surface treatment, the aluminum alloy ingot sample is placed in anhydrous ethanol for ultrasonic treatment for 5 minutes. After cleaning, it is dried to obtain a lightweight aluminum alloy.

[0083] The refining agent of this embodiment is different from that of Embodiment 1 in that the crude fluoride salt complex is composed of 15 parts of cryolite, 15 parts of potassium cryolite and 15 parts of aluminum fluoride, and the proportion of each substance in the refining agent is changed to 45 parts of crude fluoride salt complex, 15 parts of potassium oxalate and 40 parts of carnallite.

[0084] The difference between the abrasive of this embodiment and that of embodiment 1 is that the hard abrasive balls are hard glass balls, and the abrasive powder is composed of 75 parts of titanium powder, 5 parts of cerium oxide powder and 20 parts of aluminum oxide powder.

[0085] Comparative Example 1: The difference between this comparative example and Example 1 is that in the preparation process, all raw materials are added into the crucible for direct smelting.

[0086] Comparative Example 2: This comparative example differs from Example 1 in that the refining agent is changed to an equal amount of hexachloroethane.

[0087] Comparative Example 3: This comparative example differs from Example 1 in that the abrasive powder is changed to contain only aluminum oxide powder.

[0088] Performance Testing

[0089] Mechanical properties test

[0090] The tensile strength, yield strength and elongation of each embodiment and comparative example were tested in accordance with GB / T 16865-2023 Specimens and methods for tensile testing of deformed aluminum, magnesium and their alloy products.

[0091] Density and hardness testing

[0092] The lightweight aluminum alloys prepared in each embodiment and comparative example were cut into 1×1×1 cm cubic specimens, each of which was weighed 5 times, and the density was calculated and the average value was taken. The calculation formula is as follows:

[0093]

[0094] ρ is the specimen density, in g / cm 3 ;

[0095] M is the mass of the specimen, in g;

[0096] V is the volume of the specimen, in cm 3 .

[0097] The prepared 1×1×1 cm cubic specimens were tested for hardness using a microhardness tester. Ten different positions of each specimen were tested and the average value was taken.

[0098] The specific test results are shown in Table 1 below:

[0099] Table 1

[0100]

[0101] Friction and wear testing

[0102] After the aluminum alloy test pieces prepared in each embodiment and comparative example were fixed, a sliding friction test was performed under the conditions of 400 rpm and a load of 10 N. The test results are shown in Table 2 below:

[0103] Table 2

[0104] Serial number Friction coefficient Wear rate (g / N×m) Example 1 0.64 4.1 Example 2 0.67 3.9 Example 3 0.63 4.5 Example 4 0.59 4.3 Comparative Example 1 0.82 8.5 Comparative Example 2 0.71 6.7 Comparative Example 3 0.84 7.7

[0105] From the data in Table 1, it can be seen that the density of the aluminum alloys prepared in Examples 1 to 4 is between 2.70 and 2.72 g / cm 3 The tensile strength is between 329 and 336 MPa, the yield strength is between 293 and 301 MPa, the elongation is between 16.4 and 17.6%, and the Rockwell hardness is between 60.3 and 66.7 HRB, indicating that the aluminum alloy prepared by the present invention has relatively high tensile strength, yield strength and hardness. Comparative Example 1 directly melts the raw materials, resulting in insufficient smelting of the aluminum alloy, containing more impurities and pores, and the density is low while the comprehensive mechanical properties are significantly reduced; the refining agent of Comparative Example 2 is hexachloroethane, and the refining effect is worse than that of the refining agent prepared by the present invention. The aluminum alloy prepared contains a small amount of impurities and pores, and the comprehensive mechanical properties are worse than those of the aluminum alloy prepared in each embodiment. The grinding powder of the abrasive of Comparative Example 3 contains only aluminum oxide powder, and the strength and hardness of the protective layer formed by the surface strengthening treatment are weaker than those of the titanium-aluminum coating, which further illustrates that the aluminum alloy prepared by the present invention has excellent mechanical properties and good hardness while having the characteristics of lightweight.

[0106] It can be seen from the data in Table 2 that the friction coefficient of the aluminum alloys prepared in Examples 1 to 4 is between 0.59 and 0.67, and the wear rate is between 3.9 and 4.5 g / N×m, indicating that the aluminum alloy prepared in the present invention has excellent wear resistance. The wear rate of Comparative Example 1 is greater than the wear rates of each embodiment and the remaining comparative examples, indicating that the impurity content of the aluminum alloy has a greater impact on the wear resistance.

[0107] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0108] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A lightweight aluminum alloy with excellent wear resistance, characterized in that: The invention comprises the following elements in percentage by mass: 0.1-0.3wt% zinc, 0.5-1wt% copper, 0.5-0.7wt% silicon, 0.8-1.2wt% magnesium, 0.1-0.3wt% titanium, 0.05-0.2wt% cerium, 0.1-0.2wt% manganese, 0.1-0.3wt% nickel, less than 0.03wt% iron as impurity element and less than 0.005wt% other unavoidable impurity elements, and the balance is aluminum.

2. A lightweight aluminum alloy with excellent wear resistance according to claim 1, characterized in that: The lightweight aluminum alloy is prepared from the following raw materials: pure aluminum, pure magnesium, pure zinc, Al-10Si aluminum-silicon master alloy, Al-10Ni aluminum-nickel master alloy, Al-50Cu aluminum-copper master alloy, Al-10Ce aluminum-cerium master alloy, Al-10Mn aluminum-manganese master alloy and Al-5Ti aluminum-titanium master alloy.

3. A method for preparing a lightweight aluminum alloy with excellent wear resistance, characterized in that: The steps include: S1. Preheating treatment: weigh the corresponding raw materials according to the mass percentage of the elements, preheat the raw materials to 400-450°C, and preheat the crucible to 500-600°C; S2, smelting: add pure aluminum into a crucible, heat to 720-780°C, until pure aluminum is completely melted, add aluminum silicon, aluminum nickel, aluminum copper, aluminum manganese and aluminum titanium master alloy in a stirring state, then add pure magnesium and pure zinc, stir until all are melted, finally cool to 720-730°C, add aluminum cerium master alloy for modification, and let stand for 5-10 minutes; S3, refining: after smelting, the crucible temperature is adjusted to 740-760°C, and the refining agent is added to keep the temperature for 5-10 minutes, and then the pulse rotary blowing process is used to refine and remove the surface scum. The pulse rotary blowing parameters are set to an air flow rate of 5-8 L / min, a stirring speed of 50-100 rpm, and a stirring time of 5-10 minutes; S4, casting and molding: pouring the aluminum alloy melt after refining into a mold immediately for casting and molding to obtain an aluminum alloy ingot sample; S5. Surface treatment: Fix the aluminum alloy ingot sample, and use an air compressor to spray the abrasive to perform surface impact treatment on the aluminum alloy ingot sample; S6. Surface cleaning: After the surface treatment, the aluminum alloy ingot sample is placed in a cleaning solution for ultrasonic treatment for 5 to 10 minutes. After cleaning, it is dried to obtain a lightweight aluminum alloy.

4. The method for preparing a lightweight aluminum alloy with excellent wear resistance according to claim 3, characterized in that: Before the preheat treatment of the crucible in S1, the crucible is also cleaned with deionized water, dried at 200-300°C for 1-2h, and 10-15 parts of sodium silicate and 7-10 parts of zinc oxide are added to 100-120 parts of deionized water in parts by weight to prepare a protective liquid, which is then applied and dried at 200-300°C for 1-2h; the heating temperature rise rate in S2 is 5±0.2°C / min, and the cooling rate is 2.5±0.2°C / min; the heating temperature rise rate in S3 is 5±0.2°C / min.

5. The method for preparing a lightweight aluminum alloy with excellent wear resistance according to claim 3, characterized in that: In the S4, the aluminum alloy melt is injected into a mold with a temperature of 200-300°C at a speed of 2±0.5m / s and cooled naturally; the surface treatment parameters in the S5 are set as follows: the angle between the injection direction and the normal line of the sample surface is less than 60°, the injection pressure is 0.5-0.6Mpa, and the nozzle distance is 70-100mm; the cleaning liquid in the S6 is any one of anhydrous ethanol, anhydrous methanol and acetone solution.

6. The method for preparing a lightweight aluminum alloy with excellent wear resistance according to claim 3, characterized in that: The method for preparing the refining agent in S3 comprises the following steps: S11, placing cryolite, potassium cryolite and aluminum fluoride in a crucible, heating to 200-300°C for dehydration for 3-4 hours, then heating to 700-750°C for melting and heat preservation for 10-20 minutes, stirring the melt continuously during the heat preservation period, pouring and solidifying the melt after the heat preservation, and crushing and grinding to a particle size of less than 1 mm after cooling to obtain a crude fluoride salt complex; S12. Evenly mix the crude fluoride salt complex, potassium oxalate and carnallite, and obtain a refining agent after drying.

7. The method for preparing a lightweight aluminum alloy with excellent wear resistance according to claim 6, characterized in that: The raw materials used in the preparation process of the refining agent are 10-15 parts of cryolite, 10-15 parts of potassium cryolite, 10-15 parts of aluminum fluoride, 5-30 parts of potassium oxalate and 40-50 parts of carnallites by mass. The carnallites are dehydrated low-sodium carnallites with a sodium chloride content of less than 5% and a magnesium chloride content of less than 40%.

8. The method for preparing a lightweight aluminum alloy with excellent wear resistance according to claim 3, characterized in that: The method for preparing the abrasive in S5 comprises the following steps: S21, placing the hard grinding balls in a solvent for ultrasonic cleaning for 10 to 15 minutes, and drying after cleaning; S22, after the hard grinding ball is sprayed with the grinding liquid for absorption, it is put into the grinding powder and stirred evenly, so that the grinding powder is evenly absorbed on the surface of the hard grinding ball to obtain the grinding material.

9. The method for preparing a lightweight aluminum alloy with excellent wear resistance according to claim 8, characterized in that: The hard grinding balls in S21 are any one of hard glass balls, ceramic balls and steel balls; the solvent is any one of anhydrous ethanol, anhydrous methanol and acetone solution; the adsorption grinding liquid in S22 is composed of a mixture of 15 parts of potassium sorbate, 10 parts of sodium silicate, 15 parts of triethanolamine and 60 parts of deionized water in parts by mass; the grinding powder is composed of a mixture of 70-80 parts of titanium powder, 5-6 parts of cerium oxide powder and 14-25 parts of aluminum oxide powder in parts by mass.

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