High-toughness die-casting aluminum alloy material and preparation method thereof

Abstract

The application belongs to the technical field of aluminum alloy materials, and particularly relates to a high-strength and high-toughness die-casting aluminum alloy material and a preparation method thereof. The aluminum alloy material comprises the following components in a percentage by weight: Si: 12.0-14.0%; Fe: <=0.1%; Cu: <=0.05%; Mg: 1.0-1.5%; Mn: 0.8-1.0%; Ti: <=0.3%; Zn: 5.0-7.0%; Ni: <=0.50%; Zr: 0.30-0.50%; V: 0.35-0.55%; Sr: <=0.06%; RE: <=0.5%, and the rest is Al. The Al is derived from aluminum alloy waste. The application fully utilizes elements such as silicon, magnesium, manganese, zinc, zirconium and vanadium, optimally designs the composition of the alloy material, and effectively improves the die-casting filling performance of the eutectic aluminum-silicon alloy. The aluminum melt overheating treatment is used to eliminate the heredity of the material.

Description

Technical Field

[0001] This invention belongs to the field of aluminum alloy material technology, specifically a high-strength and high-toughness die-cast aluminum alloy material and its preparation method. Background Technology

[0002] With the booming development of the die-cast aluminum alloy industry, aluminum alloy materials are widely used as the preferred material for machinery, especially automobiles, due to their advantages such as lightweight, high strength and toughness, corrosion resistance and recyclability.

[0003] Currently, aluminum alloy die-cast parts are trending towards larger, thinner-walled, more complex, and higher-strength, tougher designs, requiring aluminum alloy materials with high flowability, high strength, and high toughness during mold filling. Furthermore, the traditional primary aluminum production process is energy-intensive and generates significant emissions. Using traditional primary aluminum as the main raw material for aluminum alloy production easily exacerbates the burden on the die-cast aluminum alloy industry and contributes to energy waste.

[0004] Based on the above, the recycling of waste aluminum has significant economic advantages. Because aluminum is highly corrosion-resistant, it is almost never corroded during use, resulting in minimal loss and allowing for repeated recycling. Therefore, using recycled waste aluminum to produce aluminum alloys has a significant economic advantage over using primary aluminum.

[0005] Therefore, the present invention provides a high-strength and high-toughness die-cast aluminum alloy material and its preparation method. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by this invention to solve its technical problem is as follows: a high-strength and high-toughness die-cast aluminum alloy material, wherein the weight percentage of each component in the aluminum alloy material is: Si: 12.0-14.0%; Fe: 0.08%-0.1%; Cu: 0.01%-0.05%; Mg: 1.0-1.5%; Mn: 0.8-1.0%; Ti: 0.15%-0.3%; Zn: 5.0-7.0%; Ni: 0.12%-0.50%; Zr: 0.30-0.50%; V: 0.35-0.55%; Sr: 0.03%-0.06%; RE: 0.18%-0.5%, with the remainder being Al; wherein the Al is derived from aluminum alloy scrap.

[0008] Preferably, the aluminum alloy waste is a combination of electrolytic aluminum, automotive shredded material, and aluminum processing cutting waste.

[0009] A method for preparing a high-strength and high-toughness die-cast aluminum alloy material, the method being as follows:

[0010] Step 1, Smelting and Overheating: Aluminum alloy scrap, industrial silicon and master alloy are fed into an industrial smelting furnace after batching. The smelting temperature is controlled at 880~900℃. Overheating is carried out to eliminate the material inheritance in the material and to stir it thoroughly. Then the temperature of the aluminum alloy melt is reduced to 720~760℃ to obtain aluminum alloy melt with qualified chemical composition.

[0011] Step 2, Purification and Modification: The aluminum alloy melt is purified in a refining furnace by adding solid refining agents and injecting high-purity inert gas to refine and degas the aluminum alloy melt, as well as removing slag and allowing it to settle; and the aluminum alloy melt is modified using Sr and RE, including refining the eutectic silicon phase; the purification treatment time is controlled at 60~90 min and the purification treatment temperature is controlled at 720~760℃;

[0012] Step 3: Molding: The purified and modified aluminum alloy melt is introduced into the molding equipment and cast into a high-strength and tough aluminum alloy material that does not require heat treatment.

[0013] The intermediate alloy includes metallic iron, copper, magnesium, zinc, nickel, manganese, titanium, zirconium, vanadium, strontium, and rare earth elements.

[0014] Preferably, the method for controlling the ingredients in step one is as follows:

[0015] Calculate the required amount of each element based on the expected content of each element in the aluminum alloy material;

[0016] Obtain the labeled content of each element in aluminum alloy scrap;

[0017] The amount of aluminum alloy scrap to be added is calculated based on the required amount and actual content of each element.

[0018] The ingredients are prepared according to the calculated amount of aluminum alloy scrap.

[0019] Preferably, the method for calculating the amount of aluminum alloy scrap added includes:

[0020] Obtain the required quantity and labeled content of each element;

[0021] According to the formula:

[0022]

[0023] in, This refers to the amount of aluminum alloy scrap added. For the required quantity of elements, For burn-off rate, Label the element content in aluminum alloy scrap;

[0024] Based on the formula, the amount of each aluminum alloy scrap to be added is calculated.

[0025] Preferably, the method for calculating the amount of aluminum alloy scrap added further includes:

[0026] Obtain historical aluminum alloy material preparation data; the historical aluminum alloy material preparation data includes the types of aluminum alloy scrap, the amount added, and the changes in the content of each element before and after smelting;

[0027] Based on historical aluminum alloy material preparation data, the required amount of each element and the actual amount of each element before and after smelting were extracted.

[0028] Calculate the burn-off rate of each element at different melting temperatures based on the required quantity and actual quantity of each element.

[0029] The burn-off rates of each element at different melting temperatures were compiled into a burn-off rate database;

[0030] Based on the burn-off rate database, obtain the burn-off rate of the corresponding element. ;

[0031] The actual amount of each element is the detected value of the content of each element in the aluminum alloy melt.

[0032] Preferably, the method for controlling the ingredients in step one further includes:

[0033] Aluminum alloy scrap is preferentially fed into the smelting furnace, and the smelting temperature is controlled at 700℃.

[0034] After the aluminum alloy scrap is completely transformed into melt, test the difference between the actual amount of the element and the required amount of the element.

[0035] If the difference is greater than the threshold, then the element is replenished until the difference between the actual quantity of the element and the required quantity of the element is less than or equal to the threshold; otherwise, if the difference is less than or equal to the threshold, then the element is not replenished.

[0036] Then add industrial silicon and master alloy, and control the melting temperature at 880~900℃;

[0037] After thorough stirring, an aluminum alloy melt is obtained. Then, the difference between the actual amount of each element in the aluminum alloy melt and the required amount of each element is tested. If the difference is greater than the threshold, the element is added; otherwise, the element is not added.

[0038] Preferably, the method for controlling the high-purity inert gas in step two is as follows:

[0039] Observe the state of the aluminum-silicon alloy melt;

[0040] Based on the state of the aluminum-silicon alloy melt, the blowing speed and angle of high-purity inert gas are dynamically adjusted.

[0041] Preferably, the method for observing the state of the aluminum-silicon alloy melt is as follows:

[0042] Construct a sensor array for observing the state of molten aluminum alloy;

[0043] Acquire real-time data monitored by the sensor array;

[0044] Based on the analysis of real-time data, the system outputs the judgment result of the molten state of aluminum alloy;

[0045] The determination results of the molten state of the aluminum alloy include a first state, a second state, a third state, and a fourth state;

[0046] The first state satisfies the condition that the bubbles on the surface of the aluminum alloy melt are large and aggregated.

[0047] The second state satisfies the condition that the bubbles on the surface of the aluminum alloy melt are large and dispersed;

[0048] The third state satisfies the condition that the bubbles on the surface of the aluminum alloy melt are small and aggregated.

[0049] The fourth state satisfies the condition that the bubbles on the surface of the aluminum alloy melt are small and dispersed.

[0050] Preferably, the method for dynamically adjusting the blowing speed and angle of the high-purity inert gas is as follows:

[0051] Obtain the results of the determination of the molten state of aluminum alloy;

[0052] The injection speed and angle of the high-purity inert gas are dynamically adjusted based on the judgment results.

[0053] When the aluminum alloy melt is in the first state, increase the blowing speed of the high-purity inert gas and adjust the blowing angle to 30°.

[0054] When the aluminum alloy melt is in the second state, maintain the blowing speed of high-purity inert gas and adjust the blowing angle from 30° to 90°.

[0055] When the aluminum alloy melt is in the third state, increase the blowing speed of high-purity inert gas and maintain the blowing angle.

[0056] When the aluminum alloy melt is in the fourth state, the blowing speed of high-purity inert gas is maintained and the blowing angle is maintained at 90°.

[0057] The beneficial effects of this invention are as follows:

[0058] (1) This invention makes full use of elements such as silicon, magnesium, manganese, zinc, zirconium, and vanadium. By scientifically optimizing the composition of alloy materials, eutectic aluminum-silicon alloys can effectively improve the die-casting filling performance of materials. By using the overheating treatment of aluminum melt, the material's heredity is eliminated. A small amount of Sr element and rare earth elements are added to refine the grains, which significantly improves the comprehensive performance of cast aluminum alloys.

[0059] (2) The aluminum alloy material of the present invention has a tensile strength greater than 370MPa, a yield strength greater than 300MPa, and an elongation after fracture greater than 10%, and has the advantages of high strength and good toughness. The performance requirements of die-cast structural parts can be met by die casting in the F state.

[0060] (3) This invention utilizes aluminum alloy scrap to cast aluminum alloy materials. By testing and calculating the difference between the actual amount of aluminum and the required amount of aluminum during the batching stage, aluminum is added when the difference exceeds the threshold. The proportion of each element in the aluminum alloy melt is strictly controlled to be consistent with the expected proportion. In addition, during the aluminum alloy melt purification stage, the blowing speed and angle of high-purity inert gas are dynamically adjusted through the state feedback of the aluminum alloy melt, so as to significantly improve the mechanical properties of the aluminum alloy melt. Attached Figure Description

[0061] The invention will now be further described with reference to the accompanying drawings.

[0062] Figure 1 This is a flowchart of the preparation process of the present invention. Detailed Implementation

[0063] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0064] The high-strength and high-toughness die-cast aluminum alloy material described in this embodiment of the invention comprises the following components by weight percentage: Si: 12.0-14.0%; Fe: 0.08%-0.1%; Cu: 0.01%-0.05%; Mg: 1.0-1.5%; Mn: 0.8-1.0%; Ti: 0.15%-0.3%; Zn: 5.0-7.0%; Ni: 0.12%-0.50%; Zr: 0.30-0.50%; V: 0.35-0.55%; Sr: 0.03%-0.06%; RE: 0.18%-0.5%, with the remainder being Al; the Al is derived from aluminum alloy scrap.

[0065] In one embodiment, the aluminum alloy scrap is a combination of electrolytic aluminum, automotive shredded material, and aluminum processing cutting scrap.

[0066] like Figure 1 As shown, a method for preparing a high-strength and high-toughness die-cast aluminum alloy material is described below:

[0067] Step 1, Smelting and Overheating: Aluminum alloy scrap, industrial silicon and master alloy are fed into an industrial smelting furnace after batching. The smelting temperature is controlled at 880~900℃. Overheating is carried out to eliminate the material inheritance in the material and to stir it thoroughly. Then the temperature of the aluminum alloy melt is reduced to 720~760℃ to obtain aluminum alloy melt with qualified chemical composition.

[0068] Step 2, Purification and Modification: The aluminum alloy melt is purified in a refining furnace by adding solid refining agents and injecting high-purity inert gas to refine and degas the aluminum alloy melt, as well as removing slag and allowing it to settle; and the aluminum alloy melt is modified using Sr and RE, including refining the eutectic silicon phase; the purification treatment time is controlled at 60~90 min and the purification treatment temperature is controlled at 720~760℃;

[0069] Step 3: Molding: The purified and modified aluminum alloy melt is introduced into the molding equipment and cast into a high-strength and tough aluminum alloy material that does not require heat treatment.

[0070] The intermediate alloy includes metallic iron, copper, magnesium, zinc, nickel, manganese, titanium, zirconium, vanadium, strontium, and rare earth elements.

[0071] To achieve high-strength and high-toughness aluminum alloy casting, in one embodiment of the present invention, elements such as silicon, magnesium, manganese, zinc, zirconium, and vanadium are fully utilized. By scientifically optimizing the composition of the alloy material, the eutectic aluminum-silicon alloy prepared can effectively improve the die-casting filling performance of the material. Furthermore, by using overheat treatment of the aluminum melt, the material inheritance in the aluminum alloy melt is eliminated. Finally, by adding a small amount of Sr element and rare earth elements to refine the grains, the comprehensive performance of the prepared aluminum alloy material is significantly improved.

[0072] In one embodiment, the method for controlling the ingredients in step one is as follows:

[0073] Calculate the required amount of each element based on the expected content of each element in the aluminum alloy material;

[0074] Obtain the labeled content of each element in aluminum alloy scrap;

[0075] The amount of aluminum alloy scrap to be added is calculated based on the required amount and actual content of each element.

[0076] The ingredients are prepared according to the calculated amount of aluminum alloy scrap.

[0077] To scientifically optimize the composition of aluminum alloy materials and achieve high strength and toughness, in one embodiment of this invention, the element content of the aluminum alloy melt is designed to be different based on a uniform melt weight. Aluminum alloy materials of the same weight but with different actual element contents are prepared according to the different element contents of the aluminum alloy melt. Performance tests are then conducted on multiple aluminum alloy materials to ultimately obtain an aluminum alloy material that meets the expected performance, and the expected element content of the aluminum alloy material that meets the expected performance is also obtained. Specifically, by setting a uniform melt weight and changing the expected content of each element in the melt, the required amount of the corresponding element in the aluminum alloy scrap is calculated based on the expected content of each element in the melt. Taking aluminum as an example, in this embodiment, the source of aluminum is aluminum alloy scrap, including electrolytic aluminum, automotive shredded material, and aluminum profile machining cutting waste. For each intermediate alloy used, its specific alloying elements and their contents need to be known. This information can usually be found in the product manual or technical specifications of the intermediate alloy. For aluminum alloy scrap, the aluminum content can be analyzed by instrument testing.

[0078] As mentioned above, since the aluminum content in aluminum alloy scrap varies, when using any aluminum alloy scrap as a raw material for casting aluminum alloy materials, it is necessary to calculate the amount of aluminum alloy scrap to be added. Based on the above, the required amount of aluminum in the aluminum alloy melt is obtained according to the weight of the aluminum alloy melt to be prepared, and then the required amount of aluminum alloy scrap to be added is calculated according to the marked content of aluminum in the aluminum alloy scrap used.

[0079] Based on the calculated amount of aluminum alloy scrap added, it is used as a raw material for aluminum, and is fed into the smelting furnace along with industrial silicon and intermediate alloys to cast the aluminum alloy melt.

[0080] In one embodiment, the method for calculating the amount of aluminum alloy scrap added includes:

[0081] Obtain the required quantity and labeled content of each element;

[0082] According to the formula:

[0083]

[0084] in, This refers to the amount of aluminum alloy scrap added. For the required quantity of elements, For burn-off rate, Label the element content in aluminum alloy scrap;

[0085] Based on the formula, the amount of each aluminum alloy scrap to be added is calculated.

[0086] Based on the above, in one embodiment of the present invention, when calculating the amount of aluminum alloy scrap to be added, the element requirements of the cast aluminum alloy material and the element content marked in the aluminum alloy scrap are taken into account. The required amount of aluminum alloy scrap can be calculated according to the above formula. It is worth noting that the element burn-off rate also needs to be considered. Generally speaking, if the performance test results are significantly different from the expected performance after the aluminum alloy material is cast, it may be because the element burn-off rate is high during the smelting process, resulting in the actual content of each element in the cast aluminum alloy material not matching the expected content. Therefore, when calculating the amount of each type of aluminum alloy scrap to be added, it is also necessary to combine the burn-off rate to obtain the actual amount of each type of aluminum alloy scrap to avoid errors that could affect the performance measurement of the aluminum alloy material.

[0087] For example, taking Zn as an example, if the desired aluminum alloy material is expected to contain 5% Zn, but the Zn master alloy only contains 10% Zn, then to ensure the aluminum alloy material contains 5% Zn, 50% Zn master alloy needs to be added during the batching stage. If, based on historical data analysis, the Zn burn-off rate is 2% under uniform melting temperature conditions, then 51% Zn master alloy needs to be added during the batching stage. Furthermore, since aluminum alloy scrap contains a variety of elements, the amount of aluminum alloy scrap to be added is calculated first based on the required amount of aluminum, and then the amount of other elements in the aluminum alloy scrap is calculated to deduce the additional master alloy to be added, so that the proportion of each element in the prepared aluminum alloy material is consistent with the expected content.

[0088] In one embodiment, the method for calculating the amount of aluminum alloy scrap added further includes:

[0089] Obtain historical aluminum alloy material preparation data; the historical aluminum alloy material preparation data includes the types of aluminum alloy scrap, the amount added, and the changes in the content of each element before and after smelting;

[0090] Based on historical aluminum alloy material preparation data, the required amount of each element and the actual amount of each element before and after smelting were extracted.

[0091] Calculate the burn-off rate of each element at different melting temperatures based on the required quantity and actual quantity of each element.

[0092] The burn-off rates of each element at different melting temperatures were compiled into a burn-off rate database;

[0093] Based on the burn-off rate database, obtain the burn-off rate of the corresponding element. ;

[0094] The actual amount of each element is the detected value of the content of each element in the aluminum alloy melt.

[0095] Based on the above, in the aluminum alloy material preparation process, in addition to the variable of different element contents, there is also the variable of melting temperature. Moreover, the burn-off rate is directly related to the melting temperature. Therefore, it can be understood that at different melting temperatures, the burn-off rate of each element will be different. Therefore, in one embodiment of the present invention, by obtaining historical aluminum alloy material preparation data and extracting the required amount and actual amount of each element before and after melting, the burn-off rate of each element at different melting temperatures can be calculated. By statistically analyzing the burn-off rate of each element at different melting temperatures, it can be compiled into a burn-off rate database. In the subsequent aluminum alloy material casting batching process, the amount of aluminum alloy scrap added can be calculated based on the burn-off rate published in the burn-off rate database to avoid omitting the burn-off rate of elements, which would cause the content of each element in the cast aluminum alloy material to be inconsistent with the expected content, resulting in a large deviation in performance testing.

[0096] In one embodiment, the method for controlling the ingredients in step one further includes:

[0097] Aluminum alloy scrap is preferentially fed into the smelting furnace, and the smelting temperature is controlled at 700℃.

[0098] After the aluminum alloy scrap is completely transformed into melt, test the difference between the actual amount of the element and the required amount of the element.

[0099] If the difference is greater than the threshold, then the element is replenished until the difference between the actual quantity of the element and the required quantity of the element is less than or equal to the threshold; otherwise, if the difference is less than or equal to the threshold, then the element is not replenished.

[0100] Then add industrial silicon and master alloy, and control the melting temperature at 880~900℃;

[0101] After thorough stirring, an aluminum alloy melt is obtained. Then, the difference between the actual amount of each element in the aluminum alloy melt and the required amount of each element is tested. If the difference is greater than the threshold, the element is added; otherwise, the element is not added.

[0102] Based on the above, the required amount of aluminum alloy scrap is calculated first based on the required amount of aluminum. Then, based on the actual amount of other elements contained in aluminum, it is deduced whether other elemental substances need to be added. In one embodiment of the present invention, aluminum alloy scrap is added first. After the aluminum alloy scrap is completely transformed into melt, the types and contents of elements contained in the melt are tested. If the difference between the actual amount of elements and the required amount of elements is greater than a threshold, taking aluminum as an example, then elemental aluminum is added. If the difference is less than the threshold, then elemental aluminum is not added. After the aluminum element is determined, the required amount of intermediate alloy to be added is deduced based on the contents of other elements contained in the aluminum alloy scrap, so that the contents of each element in the prepared aluminum alloy material are consistent with the expected contents.

[0103] Furthermore, since the intermediate alloys added later also contain at least two metallic elements, such as aluminum-titanium, aluminum-zirconium, and aluminum-vanadium intermediate alloys, the main element considered when calculating the demand for aluminum alloy scrap is aluminum. This ensures that the content of aluminum, which accounts for a large proportion of the aluminum alloy material, is consistent with the expected content. Other elements that may be contained in the aluminum alloy scrap are then calculated based on the actual amount of other elements contained in aluminum to determine whether other elemental substances need to be added.

[0104] In one embodiment, the method for controlling the high-purity inert gas in step two is as follows:

[0105] Observe the state of the aluminum-silicon alloy melt;

[0106] Based on the state of the aluminum-silicon alloy melt, the blowing speed and angle of high-purity inert gas are dynamically adjusted.

[0107] In one embodiment, the method for observing the state of the aluminum-silicon alloy melt is as follows:

[0108] Construct a sensor array for observing the state of molten aluminum alloy;

[0109] Acquire real-time data monitored by the sensor array;

[0110] Based on the analysis of real-time data, the system outputs the judgment result of the molten state of aluminum alloy;

[0111] The determination results of the molten state of the aluminum alloy include a first state, a second state, a third state, and a fourth state;

[0112] The first state satisfies the condition that the bubbles on the surface of the aluminum alloy melt are large and aggregated.

[0113] The second state satisfies the condition that the bubbles on the surface of the aluminum alloy melt are large and dispersed;

[0114] The third state satisfies the condition that the bubbles on the surface of the aluminum alloy melt are small and aggregated.

[0115] The fourth state satisfies the condition that the bubbles on the surface of the aluminum alloy melt are small and dispersed.

[0116] In existing technologies, during the refining process of aluminum alloy molten material, refining agents need to be added to the refining furnace to improve the refining effect and separate impurities. Therefore, after adding the refining agent, inert gas needs to be introduced to prevent increased intake and instability of the alloy composition. The inert gas is sprayed into the aluminum alloy molten material along with the refining agent through a rotating rotor, forming a large number of bubbles. As the bubbles rise, they adsorb and carry away hydrogen and some oxide inclusions from the aluminum alloy molten material, improving the purity of the aluminum alloy molten material and reducing porosity. When the bubbles rise to the surface of the aluminum alloy molten material, the hydrogen in the bubbles dissipates into the atmosphere. It is worth noting that during the process from bubble generation to the bubbles rising to the surface of the aluminum alloy molten material, controlling the blowing speed and angle of the inert gas can increase the contact area between the bubbles and the aluminum alloy molten material, accelerating bubble breakage and dispersion, thereby more thoroughly removing hydrogen and oxide inclusions from the aluminum alloy molten material and maximizing the refining effect.

[0117] Based on the above, since introducing high-purity inert gas is beneficial for purifying and refining aluminum alloy melt, the blowing speed and angle of high-purity inert gas can be dynamically controlled according to the state of aluminum alloy melt during the refining process, thereby accelerating the refining process and maximizing the refining effect. In one embodiment of the present invention, the first state, the second state, the third state, and the fourth state are used to characterize the degree of refining after the high-purity inert gas is introduced into the aluminum alloy melt. More specifically, the degree of refining of the aluminum alloy melt is characterized by collecting the bubble state of the aluminum alloy melt in the refining furnace based on the sensor array. As mentioned above, the bubble state includes size and aggregation / dispersion.

[0118] In one embodiment, the method for dynamically adjusting the blowing speed and angle of the high-purity inert gas is as follows:

[0119] Obtain the results of the determination of the molten state of aluminum alloy;

[0120] The injection speed and angle of the high-purity inert gas are dynamically adjusted based on the judgment results.

[0121] When the aluminum alloy melt is in the first state, increase the blowing speed of the high-purity inert gas and adjust the blowing angle to 30°.

[0122] When the aluminum alloy melt is in the second state, maintain the blowing speed of high-purity inert gas and adjust the blowing angle from 30° to 90°.

[0123] When the aluminum alloy melt is in the third state, increase the blowing speed of high-purity inert gas and maintain the blowing angle.

[0124] When the aluminum alloy melt is in the fourth state, the blowing speed of high-purity inert gas is maintained and the blowing angle is maintained at 90°.

[0125] Based on the above, the state of bubbles in the aluminum alloy melt collected by the sensor array characterizes the refining degree of the aluminum alloy melt. In one embodiment of the present invention, by obtaining the judgment result of the state of the aluminum alloy melt, the blowing speed and angle of high-purity inert gas are dynamically adjusted based on the judgment result. In different states of the aluminum alloy melt, by dynamically controlling the blowing speed and angle of high-purity inert gas, the refining process of the aluminum alloy melt is accelerated and the refining effect is maximized. Specifically, for the aluminum alloy melt in the first state, increasing the blowing speed of high-purity inert gas can accelerate the dispersion of bubbles by the bubble breaker. This allows for faster bubble migration, thereby reducing hydrogen and oxide inclusions in the aluminum alloy melt. For the aluminum alloy melt in the second state, when the bubbles are dispersed, it indicates good bubble migration and fluidity. At this point, it is only necessary to maintain the blowing speed of high-purity inert gas, and then adjust the blowing speed of high-purity inert gas to accelerate bubble refinement and breakup. For the aluminum alloy melt in the third state, it is only necessary to increase the blowing speed of high-purity inert gas. For the aluminum alloy melt in the fourth state, it indicates that the bubble state has reached the expected level, and it is only necessary to maintain the blowing speed and blowing angle of high-purity inert gas.

[0126] Example 1:

[0127] The percentage by mass of the components in this aluminum alloy material is:

[0128] The percentage composition by mass of the aluminum alloy material is as follows: Si: 12%; Fe: 0.1%; Cu: 0.05%; Mg: 1.5%; Mn: 1%; Ti: 0.3%; Zn: 7%; Ni: 0.5%; Zr: 0.5%; V: 0.55%; Sr: 0.06%; RE: 0.5%, with the remainder being Al.

[0129] Low-carbon preparation method:

[0130] (1) Calculate the required amount of each element according to the expected content of each element in the aluminum alloy melt, and add the materials according to the calculated amount of aluminum alloy scrap. Then, put them into the industrial melting furnace in sequence, heat them until they are completely melted, and then stir them thoroughly. Then, add industrial silicon and intermediate alloy to the industrial furnace to melt them until they are completely melted and stirred and mixed evenly. Continue to raise the temperature and control the melting temperature at 900℃. After holding the temperature for 60 minutes, lower the temperature of the aluminum alloy melt to 760℃.

[0131] (2) The obtained aluminum alloy melt is purified in a refining furnace. High-purity inert gas and solid refining agent are introduced into the aluminum alloy melt for purification. The refining temperature is controlled at 760℃ and the refining time is controlled at 50min. Then, high-purity inert gas is used for degassing. The degassing temperature is controlled at 700℃ and the degassing time is controlled at 30min. After removing slag and impurities, it is allowed to stand for 10min. Then, Sr and RE are used to modify the aluminum alloy melt between the refining and degassing processes.

[0132] (3) The aluminum alloy melt obtained after purification and modification treatment is sent to the casting machine forming equipment to obtain high-strength and tough aluminum alloy material that does not require heat treatment.

[0133] Standard tensile test bars were prepared by casting aluminum alloy materials. The tensile test results showed that the tensile strength of the aluminum alloy material was 384 MPa, the yield strength was 329 MPa, and the elongation after fracture was 10.3%.

[0134] Example 2:

[0135] The percentage composition by mass of the aluminum alloy material is as follows: Si: 14%; Fe: 0.1%; Cu: 0.05%; Mg: 1.5%; Mn: 1%; Ti: 0.3%; Zn: 7%; Ni: 0.5%; Zr: 0.5%; V: 0.55%; Sr: 0.06%; RE: 0.5%, with the remainder being Al.

[0136] Low-carbon preparation method:

[0137] (1) Calculate the required amount of each element according to the expected content of each element in the aluminum alloy melt, and add the materials according to the calculated amount of aluminum alloy scrap. Then, put them into the industrial melting furnace in sequence, heat them until they are completely melted, and then stir them thoroughly. Then, add industrial silicon and intermediate alloy to the industrial furnace to melt them until they are completely melted and stirred and mixed evenly. Continue to raise the temperature and control the melting temperature at 900℃. After holding the temperature for 60 minutes, lower the temperature of the aluminum alloy melt to 760℃.

[0138] (2) The obtained aluminum alloy melt is purified in a refining furnace. High-purity inert gas and solid refining agent are introduced into the aluminum alloy melt for purification. The refining temperature is controlled at 760℃ and the refining time is controlled at 50min. Then, high-purity inert gas is used for degassing. The degassing temperature is controlled at 700℃ and the degassing time is controlled at 30min. After removing slag and impurities, it is allowed to stand for 10min. Then, Sr and RE are used to modify the aluminum alloy melt between the refining and degassing processes.

[0139] (3) The aluminum alloy melt obtained after purification and modification treatment is sent to the casting machine forming equipment to obtain high-strength and tough aluminum alloy material that does not require heat treatment.

[0140] Standard tensile test bars were prepared by casting aluminum alloy materials. The tensile test results showed that the tensile strength of the aluminum alloy material was 392 MPa, the yield strength was 348 MPa, and the elongation after fracture was 10.8%.

[0141] Example 3:

[0142] Si: 12.4%; Fe: 0.08%; Cu: 0.01%; Mg: 1.13%; Mn: 0.82%; Ti: 0.15%; Zn: 5.2%; Ni: 0.12%; Zr: 0.33%; V: 0.38%; Sr: 0.03%; RE: 0.18%, with the remainder being Al.

[0143] Low-carbon preparation method:

[0144] (1) Calculate the required amount of each element according to the expected content of each element in the aluminum alloy melt, and add the materials according to the calculated amount of aluminum alloy scrap. Then, put them into the industrial melting furnace in sequence, heat them until they are completely melted, and then stir them thoroughly. Then, add industrial silicon and intermediate alloy to the industrial furnace to melt them until they are completely melted and stirred and mixed evenly. Continue to raise the temperature and control the melting temperature at 900℃. After holding the temperature for 60 minutes, lower the temperature of the aluminum alloy melt to 760℃.

[0145] (2) The obtained aluminum alloy melt is purified in a refining furnace. High-purity inert gas and solid refining agent are introduced into the aluminum alloy melt for purification. The refining temperature is controlled at 760℃ and the refining time is controlled at 50min. Then, high-purity inert gas is used for degassing. The degassing temperature is controlled at 700℃ and the degassing time is controlled at 30min. After removing slag and impurities, it is allowed to stand for 10min. Then, Sr and RE are used to modify the aluminum alloy melt between the refining and degassing processes.

[0146] (3) The aluminum alloy melt obtained after purification and modification treatment is sent to the casting machine forming equipment to obtain high-strength and tough aluminum alloy material that does not require heat treatment.

[0147] Standard tensile test bars were prepared by casting aluminum alloy materials. The tensile test results showed that the tensile strength of the aluminum alloy material was 378 MPa, the yield strength was 326 MPa, and the elongation after fracture was 10.6%.

[0148] Example 4:

[0149] The percentage composition by mass of the aluminum alloy material is as follows: Si: 16%; Fe: 0.5%; Cu: 0.2%; Mg: 2.0%; Mn: 1.5%; Ti: 0.6%; Zn: 3%; Ni: 1.0%; Zr: 1.0%; V: 0.8%; Sr: 0.1%; RE: 1.0%, with the remainder being Al.

[0150] Low-carbon preparation method:

[0151] (1) Calculate the required amount of each element according to the expected content of each element in the aluminum alloy melt, and add the materials according to the calculated amount of aluminum alloy scrap. Then, put them into the industrial melting furnace in sequence, heat them until they are completely melted, and then stir them thoroughly. Then, add industrial silicon and intermediate alloy to the industrial furnace to melt them until they are completely melted and stirred and mixed evenly. Continue to raise the temperature and control the melting temperature at 900℃. After holding the temperature for 60 minutes, lower the temperature of the aluminum alloy melt to 760℃.

[0152] (2) The obtained aluminum alloy melt is purified in a refining furnace. High-purity inert gas and solid refining agent are introduced into the aluminum alloy melt for purification. The refining temperature is controlled at 760℃ and the refining time is controlled at 50min. Then, high-purity inert gas is used for degassing. The degassing temperature is controlled at 700℃ and the degassing time is controlled at 30min. After removing slag and impurities, it is allowed to stand for 10min. Then, Sr and RE are used to modify the aluminum alloy melt between the refining and degassing processes.

[0153] (3) The aluminum alloy melt obtained after purification and modification treatment is sent to the casting machine forming equipment to obtain high-strength and tough aluminum alloy material that does not require heat treatment.

[0154] Standard tensile test bars were prepared by casting aluminum alloy materials. The tensile test results showed that the tensile strength of the aluminum alloy material was 352 MPa, the yield strength was 308 MPa, and the elongation after fracture was 9.2%.

[0155] Example 5:

[0156] The percentage composition by mass of the aluminum alloy material is as follows: Si: 12%; Fe: 0.1%; Cu: 0.05%; Mg: 1.5%; Mn: 1%; Ti: 0.3%; Zn: 7%; Ni: 0.5%; Zr: 0.5%; V: 0.55%; Sr: 0.06%; RE: 0.5%, with the remainder being Al.

[0157] Low-carbon preparation method:

[0158] (1) Calculate the required amount of each element according to the expected content of each element in the aluminum alloy melt, and add the materials according to the calculated amount of aluminum alloy scrap. Then, put them into the industrial melting furnace in sequence, heat them until they are completely melted, and then stir them thoroughly. Then, add industrial silicon and intermediate alloy to the industrial furnace to melt them until they are completely melted and stirred and mixed evenly. Continue to raise the temperature and control the melting temperature at 900℃. After holding the temperature for 60 minutes, lower the temperature of the aluminum alloy melt to 760℃. In the material preparation stage, after the aluminum alloy scrap is completely converted into melt, test the difference between the actual amount of the element and the required amount of the element. When the difference is greater than the threshold, supplement the element.

[0159] (2) The obtained aluminum alloy melt is purified in a refining furnace by introducing high-purity inert gas and adding solid refining agent. The refining temperature is controlled at 760℃ and the refining time is controlled at 50min. Then, high-purity inert gas is used for degassing. The degassing temperature is controlled at 700℃ and the degassing time is controlled at 30min. After removing slag and impurities, it is allowed to stand for 10min. During the degassing process using high-purity inert gas, the state of the aluminum alloy melt is observed, and the blowing speed and angle of the high-purity inert gas are dynamically adjusted according to the state of the aluminum alloy melt. Then, Sr and RE are used to modify the aluminum alloy melt between the refining and degassing processes.

[0160] (3) The aluminum alloy melt obtained after purification and modification treatment is sent to the casting machine forming equipment to obtain high-strength and tough aluminum alloy material that does not require heat treatment.

[0161] Standard tensile test bars were prepared by casting aluminum alloy materials. The tensile test results showed that the tensile strength of the aluminum alloy material was 395 MPa, the yield strength was 352 MPa, and the elongation after fracture was 11.1%.

[0162] Example 6:

[0163] The percentage composition by mass of the aluminum alloy material is as follows: Si: 12%; Fe: 0.1%; Cu: 0.05%; Mg: 1.5%; Mn: 1%; Ti: 0.3%; Zn: 7%; Ni: 0.5%; Zr: 0.5%; V: 0.55%; Sr: 0.06%; RE: 0.5%, with the remainder being Al.

[0164] Low-carbon preparation method:

[0165] (1) Calculate the required amount of each element according to the expected content of each element in the aluminum alloy melt, and add the materials according to the calculated amount of aluminum alloy scrap. Then, put them into the industrial melting furnace in sequence, heat them until they are completely melted, and then stir them thoroughly. Then, add industrial silicon and intermediate alloy to the industrial furnace to melt them until they are completely melted and stirred and mixed evenly. Continue to raise the temperature and control the melting temperature at 900℃. After holding the temperature for 60 minutes, lower the temperature of the aluminum alloy melt to 760℃.

[0166] (2) The obtained aluminum alloy melt is purified in a refining furnace by introducing high-purity inert gas and adding solid refining agent. The refining temperature is controlled at 760℃ and the refining time is controlled at 50min. Then, high-purity inert gas is used for degassing. The degassing temperature is controlled at 700℃ and the degassing time is controlled at 30min. After removing slag and impurities, it is allowed to stand for 10min. During the degassing process using high-purity inert gas, the state of the aluminum alloy melt is observed, and the blowing speed and angle of the high-purity inert gas are dynamically adjusted according to the state of the aluminum alloy melt. Then, Sr and RE are used to modify the aluminum alloy melt between the refining and degassing processes.

[0167] (3) The aluminum alloy melt obtained after purification and modification treatment is sent to the casting machine forming equipment to obtain high-strength and tough aluminum alloy material that does not require heat treatment.

[0168] Standard tensile test bars were prepared by casting aluminum alloy materials. The tensile test results showed that the tensile strength of the aluminum alloy material was 394 MPa, the yield strength was 353 MPa, and the elongation after fracture was 10.9%.

[0169] Example 7:

[0170] The percentage composition by mass of the aluminum alloy material is as follows: Si: 12%; Fe: 0.1%; Cu: 0.05%; Mg: 1.5%; Mn: 1%; Ti: 0.3%; Zn: 7%; Ni: 0.5%; Zr: 0.5%; V: 0.55%; Sr: 0.06%; RE: 0.5%, with the remainder being Al.

[0171] Low-carbon preparation method:

[0172] (1) Calculate the required amount of each element according to the expected content of each element in the aluminum alloy melt, and add the materials according to the calculated amount of aluminum alloy scrap. Then, put them into the industrial melting furnace in sequence, heat them until they are completely melted, and then stir them thoroughly. Then, add industrial silicon and intermediate alloy to the industrial furnace to melt them until they are completely melted and stirred and mixed evenly. Continue to raise the temperature and control the melting temperature at 900℃. After holding the temperature for 60 minutes, lower the temperature of the aluminum alloy melt to 760℃. In the material preparation stage, after the aluminum alloy scrap is completely converted into melt, test the difference between the actual amount of the element and the required amount of the element. When the difference is greater than the threshold, supplement the element.

[0173] (2) The obtained aluminum alloy melt is purified in a refining furnace by introducing high-purity inert gas and adding solid refining agent. The refining temperature is controlled at 760℃ and the refining time is controlled at 50min. Then, high-purity inert gas is used for degassing. The degassing temperature is controlled at 700℃ and the degassing time is controlled at 30min. After removing slag and impurities, it is allowed to stand for 10min. During the degassing process using high-purity inert gas, the state of the aluminum alloy melt is observed, and the blowing speed and angle of the high-purity inert gas are dynamically adjusted according to the state of the aluminum alloy melt. Then, Sr and RE are used to modify the aluminum alloy melt between the refining and degassing processes.

[0174] (3) The aluminum alloy melt obtained after purification and modification treatment is sent to the casting machine forming equipment to obtain high-strength and tough aluminum alloy material that does not require heat treatment.

[0175] Standard tensile test bars were prepared by casting aluminum alloy materials. The tensile test results showed that the tensile strength of the aluminum alloy material was 398 MPa, the yield strength was 354 MPa, and the elongation after fracture was 11.4%.

[0176] Examples 1, 2, 3, and 4 are largely the same, differing only in the percentage of aluminum alloy material composition by mass. A comparison of these examples reveals a range of percentages of aluminum alloy material composition that meet performance requirements. Aluminum alloy materials cast within this range exhibit high strength and good toughness. Example 5 is also largely the same as Example 1, except that in step 1, the elemental content of the melted aluminum alloy scrap is tested, and the results determine whether additional elemental substances are needed to maintain the desired elemental content in the prepared aluminum alloy material. Example 6 is also largely the same as Example 1, except that in step 2, the blowing speed and angle of the high-purity inert gas are dynamically adjusted based on the state of the molten aluminum alloy. Example 7 is also largely the same as Example 1, except that in step 1, the elemental content of the melted aluminum alloy scrap is tested, and the results determine whether additional elemental substances are needed. Simultaneously, in step 2, the blowing speed and angle of the high-purity inert gas are dynamically adjusted based on the state of the molten aluminum alloy.

[0177] The aluminum alloy material prepared in the above embodiments was subjected to performance testing, and the test results are shown in Table 1.

[0178] Table 1

[0179]

[0180] Analysis was conducted on the aluminum alloy materials prepared according to Examples 1 to 7. The aluminum alloy materials prepared in Examples 1 to 3 all exhibited tensile strengths greater than 370 MPa, yield strengths greater than 300 MPa, and elongation after fracture greater than 10%. In contrast, the aluminum alloy material prepared in Example 4 had a tensile strength significantly lower than 370 MPa, a yield strength close to 300 MPa, and an elongation after fracture less than 10%. Therefore, using the percentage range of aluminum alloy material composition predicted in Examples 1 to 3, the prepared aluminum alloy materials could achieve tensile strengths greater than 370 MPa, yield strengths greater than 300 MPa, and elongation after fracture greater than 10%. A content greater than 10% in the F-state of die casting is sufficient to meet the performance requirements of die-cast structural parts. It is worth noting that, through Examples 5 to 7, in the process of preparing aluminum alloy materials, based on the element content test of the melted aluminum alloy scrap and the supplementation of elemental substances according to the expected content to make up for the missing element content, and by dynamically adjusting the blowing speed and angle of high-purity inert gas according to the state of the aluminum alloy melt, the tensile strength, yield strength and elongation after fracture of the prepared aluminum alloy material can be further improved. It can be inferred that by improving the process flow, the gas and impurities in the aluminum alloy melt can be further removed, resulting in a stronger comprehensive performance of the prepared aluminum alloy material.

[0181] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a high-toughness die-casting aluminum alloy material, characterized in that: The weight percentage of each component in the aluminum alloy material is: Si: 12.0-14.0%; Fe: 0.08%-0.1%; Cu: 0.01%-0.05%; Mg: 1.0-1.5%; Mn: 0.8-1.0%; Ti: 0.15%-0.3%; Zn: 5.0-7.0%; Ni: 0.12%-0.50%; Zr: 0.30-0.50%; and RE: 0.18%-0.5%, with the remainder being Al; the Al is derived from aluminum alloy waste; The aluminum alloy waste is a combination of electrolytic aluminum, automobile crushed material, and aluminum material processing cutting waste; The preparation method is as follows: V：0.35-0.55%； Sr：0.03%-0.06%； Step one, melting and superheating treatment: aluminum alloy waste, industrial silicon, and intermediate alloy are fed into an industrial melting furnace after batching, the melting temperature is controlled at 880-900°C, superheating treatment is performed to eliminate material heredity, and the material is fully stirred and uniformly distributed, then the aluminum alloy melt temperature is reduced to 720-760°C to obtain an aluminum alloy melt with qualified chemical composition; Step two, purification and modification: the aluminum alloy melt is subjected to purification treatment in a refining furnace, solid refining agent is added, high-purity inert gas is blown into the aluminum alloy melt for refining, degassing, and slagging and standing treatment; and Sr and RE are used for modification treatment of the aluminum alloy melt, including refining eutectic silicon phase; the purification treatment time is controlled at 60-90 min, and the purification treatment temperature is controlled at 720-760°C; Step three, forming: the purified and modified aluminum alloy melt is introduced into a forming equipment to be cast into a high-strength and high-toughness heat treatment-free aluminum alloy material; The intermediate alloy includes metallic iron, copper, magnesium, zinc, nickel, manganese, titanium, zirconium, vanadium, strontium, and rare earth; The batching control method in step one is: According to the expected content of each element in the aluminum alloy material, the required amount of each element is calculated; The labeled content of each element in the aluminum alloy waste is obtained; Based on the required amount of each element and the actual content of each element, the addition amount of the aluminum alloy waste is calculated; Batching is performed according to the calculated addition amount of the aluminum alloy waste; The method for calculating the addition amount of the aluminum alloy waste includes: Obtaining the required amount of each element and the labeled content of each element; According to the formula: Based on the formula, the addition amount of each aluminum alloy waste is calculated; The method for calculating the addition amount of the aluminum alloy waste further includes: Obtaining historical aluminum alloy material preparation data; the historical aluminum alloy material preparation data includes aluminum alloy waste types, addition amounts, and content changes of each element before and after melting; ； wherein, is the amount of aluminium alloy scrap added, is the amount of the element required, is the burn rate, is the elemental tag content in the aluminium alloy scrap; Based on the historical aluminum alloy material preparation data, the required amount of each element and the actual amount of each element before and after melting are extracted; According to the required amount of each element and the actual amount of each element, the burn loss rate of each element at different melting temperatures is calculated; The burn loss rates of each element at different melting temperatures are sorted into a burn loss rate database; The actual amount of each element is the detected value of the content of each element in the aluminum alloy melt; The control method of the high-purity inert gas in step two is: Observe the state of the aluminum-silicon alloy melt; According to the burn-off rate database, the burn-off rate of the corresponding element is obtained ; Based on the state of the aluminum-silicon alloy melt, dynamically adjust the blowing speed and angle of the high-purity inert gas. The batching control method in step one further includes: ​ ​ 2. The method for preparing a high-toughness die-casting aluminum alloy material according to claim 1, characterized in that: ​ The aluminum alloy waste is preferentially put into a smelting furnace, and the smelting temperature is controlled at 700 DEG C; After the aluminum alloy waste is completely converted into a melt, the difference between the actual amount of the element and the required amount of the element is tested; If the difference is greater than the threshold value, the elemental substance is supplemented until the difference between the actual amount of the element and the required amount of the element is less than or equal to the threshold value; otherwise, if the difference is less than or equal to the threshold value, the elemental substance is not supplemented; Industrial silicon and intermediate alloy are further added, and the smelting temperature is controlled at 880-900 DEG C; After sufficient stirring, an aluminum alloy melt is obtained, and the difference between the actual amount of each element in the aluminum alloy melt and the required amount of each element is tested; if the difference is greater than the threshold value, the elemental substance is supplemented; otherwise, the elemental substance is not supplemented.

3. The method for preparing a high-toughness die-casting aluminum alloy material according to claim 1, characterized in that: The method for observing the state of the aluminum-silicon alloy melt comprises the following steps: constructing a sensor array for observing the state of the aluminum alloy melt; acquiring real-time data monitored by the sensor array; outputting a judgment result of the state of the aluminum alloy melt based on analysis of the real-time data; the judgment result of the state of the aluminum alloy melt comprises a first state, a second state, a third state and a fourth state; the first state satisfies that the bubbles on the surface of the aluminum alloy melt are coarse and gathered; the second state satisfies that the bubbles on the surface of the aluminum alloy melt are coarse and dispersed; the third state satisfies that the bubbles on the surface of the aluminum alloy melt are fine and gathered; the fourth state satisfies that the bubbles on the surface of the aluminum alloy melt are fine and dispersed.

4. The method for preparing a high-toughness die-casting aluminum alloy material according to claim 3, characterized in that: The method for dynamically adjusting the blowing speed and angle of the high-purity inert gas comprises the following steps: acquiring the judgment result of the state of the aluminum alloy melt; dynamically adjusting the blowing speed and angle of the high-purity inert gas based on the judgment result: when the state of the aluminum alloy melt is the first state, the blowing speed of the high-purity inert gas is increased and the blowing angle is adjusted to 30 DEG; when the state of the aluminum alloy melt is the second state, the blowing speed of the high-purity inert gas is maintained and the blowing angle is adjusted from 30 DEG to 90 DEG; when the state of the aluminum alloy melt is the third state, the blowing speed of the high-purity inert gas is increased and the blowing angle is maintained; when the state of the aluminum alloy melt is the fourth state, the blowing speed of the high-purity inert gas is maintained and the blowing angle is maintained at 90 DEG.

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