High-toughness high-wear-resistance semi-solid extrusion-formed high-silicon aluminum alloy finished product and method thereof

Abstract

The invention relates to the technical field of high-silicon aluminum alloy material processing, in particular to a high-toughness high-wear-resistance semi-solid extrusion-formed high-silicon aluminum alloy finished product and a method thereof. The finished product is prepared by the method. The method comprises the following steps: preparing the dosages of all the raw material components according to the mass percent of all the metal components in a finished product; smelting to obtain aluminum alloy liquid; an aluminum-cerium intermediate alloy is added into the aluminum alloy liquid for refining modification treatment; an inner cooling block is added into the aluminum alloy liquid, semi-solid treatment is conducted, and semi-solid slurry is obtained; the semi-solid slurry is poured into a preheated mold, and a prefabricated aluminum alloy material is obtained through extrusion forming treatment; and opening the mold, taking out the cooled and solidified prefabricated aluminum alloy material, and machining to obtain a high-silicon aluminum alloy finished product. The high-silicon aluminum alloy finished product with high toughness and high wear resistance can be prepared.

Description

Technical Field

[0001] This invention relates to the field of high-silicon aluminum alloy material processing technology, and in particular to a high-strength, high-toughness, and high-wear-resistant semi-solid extrusion molding high-silicon aluminum alloy finished product and its method. Background Technology

[0002] Aluminum alloys possess numerous advantages, including low density, high specific strength, ease of forming and processing, good electrical and thermal conductivity, and abundant resources, leading to their wide application in aerospace, transportation, building materials, petrochemicals, defense, and power industries. With the development of modern industry and new casting technologies, the demand for aluminum alloys with high strength, excellent wear resistance, and corrosion resistance is increasing, while also placing higher demands on them. These demands require not only ultra-high strength but also improved wear resistance and fracture resistance. However, existing aluminum alloy materials still require further improvement in terms of strength, fracture resistance, and wear resistance.

[0003] Therefore, it is necessary to provide a high-strength, high-toughness, and high-wear-resistant semi-solid extrusion molding high-silicon aluminum alloy product and its method to solve the problem that existing aluminum alloy materials need further improvement in terms of strength, fracture resistance, and wear resistance. Summary of the Invention

[0004] The purpose of this invention is to provide a high-strength, high-toughness, and high-wear-resistant semi-solid extrusion molding high-silicon aluminum alloy product and its method. The specific technical solution is as follows: In a first aspect, the present invention provides a method for preparing a high-strength, high-toughness, and high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy product, comprising: Step S1, ingredient preparation, the raw material components used include: pure aluminum ingot, pure magnesium ingot, industrial crystalline silicon, aluminum-copper master alloy, aluminum-nickel master alloy, aluminum-manganese master alloy, aluminum-titanium master alloy, aluminum-zinc master alloy and aluminum-cerium master alloy; the amount of each raw material component is configured according to the mass percentage of each metal component in the high silicon aluminum alloy finished product. The mass percentages of each metal component in the finished high-silicon aluminum alloy are as follows: The composition comprises 16%~23% Si, 1%~2% Cu, 0.5%~1.5% Mg, 0.1%~0.3% Zn, 0.3%~0.6% Fe, 0.1%~0.3% Ti, 0.5%~0.8% Mn, 0.8%~1% Ni, 0.3%~0.9% Ce, 0.3% impurity elements, and the balance Al; the impurity elements include Cr and Sn. Step S2, Smelting: The prepared industrial crystalline silicon, pure aluminum ingot, aluminum-copper master alloy, aluminum-nickel master alloy, aluminum-manganese master alloy, aluminum-titanium master alloy, aluminum-zinc master alloy and pure magnesium ingot are smelted until completely melted to obtain aluminum alloy liquid; Step S3: Refinement and modification treatment. A covering agent is sprinkled on the surface of the aluminum alloy liquid to form a first covering layer. The aluminum alloy liquid is then subjected to degassing and settling treatment in sequence. Subsequently, the oxide scale and impurities on the surface of the aluminum alloy liquid are cleaned. Finally, the covering agent is sprinkled on the surface of the aluminum alloy liquid to form a second covering layer. Finally, the second covering layer is peeled off, and the aluminum-cerium master alloy is added to the aluminum alloy liquid for refinement and modification treatment. Step S4, semi-solid treatment: Before casting, add an internal cooling block to the aluminum alloy liquid to perform the semi-solid treatment and obtain a semi-solid slurry. Step S5: Extrusion molding process. The semi-solid slurry is poured into a preheated mold, and the pre-made aluminum alloy material is obtained through the extrusion molding process. Step S6: Process the finished product. Open the mold, remove the pre-made aluminum alloy material after cooling and solidification, and process it to obtain the high-silicon aluminum alloy finished product.

[0005] Optionally, in step S2, the smelting includes: first, adding 50% to 70% by mass of the industrial crystalline silicon to the bottom of the smelting furnace, then adding 60% to 70% by mass of the pure aluminum ingot on top of the industrial crystalline silicon, and introducing an inert gas or adding a protective flux into the smelting furnace to perform a first smelting process until it is completely melted; Next, the remaining mass percentage of the pure aluminum ingot and the remaining mass percentage of the industrial crystalline silicon are pressed into the bottom of the melting furnace for a second melting process until they are completely melted. Then, the aluminum-copper master alloy, the aluminum-nickel master alloy, the aluminum-manganese master alloy, the aluminum-titanium master alloy, and the aluminum-zinc master alloy are added to the melting furnace for a third melting process until they are completely melted. Finally, the melt in the smelting furnace is cooled down, and then the pure magnesium ingot is pressed into the melt until it is completely melted to obtain aluminum alloy liquid; wherein, the cooling process helps to reduce the oxidation and burning loss of the pure magnesium ingot. The melting temperature used in the first melting process is 750~860℃; The second smelting process uses a smelting temperature of 750~860℃; The third smelting process uses a smelting temperature of 740~820℃.

[0006] Optionally, in step S2, the cooling process involves reducing the temperature of the melt to 740~760°C.

[0007] Optionally, in step S3, the temperature of the refining and modification treatment is 740~760℃, and the time is 20~30min.

[0008] Optionally, in step S3, the amount of the covering agent used in the first covering layer accounts for 1% to 1.5% of the total mass of the aluminum alloy liquid; the amount of the covering agent used in the second covering layer accounts for 0.5% to 1% of the total mass of the aluminum alloy liquid; the covering agent is a mixture of NaCl and KCl, and the mass ratio of NaCl to KCl is 7:3.

[0009] Optionally, in step S3, the degassing process includes introducing inert gas into the melting furnace to degas the interior of the molten aluminum alloy. The settling time for the static treatment is 15-20 minutes.

[0010] Optionally, in step S4, the internal cooling block is a high-silicon aluminum alloy finished product, and its amount is 5% to 15% of the mass of the aluminum alloy liquid; the stirring speed used in the semi-solid treatment is 1000 to 1500 rpm.

[0011] Optionally, in step S5, the preheating treatment involves preheating the mold to 260~300℃.

[0012] Optionally, the extrusion molding process uses an injection pressure of 120~150MPa, a pressurization time of 80~100ms, an extrusion speed of 0.5~0.8m / s, and a cycle time of 100~120s. The pouring temperature of the semi-solid slurry is 650~670℃.

[0013] In a second aspect, the present invention provides a high-strength, high-toughness, high-wear-resistant semi-solid extrusion molded high-silicon aluminum alloy finished product, which is prepared by the aforementioned method for preparing the high-strength, high-toughness, high-wear-resistant semi-solid extrusion molded high-silicon aluminum alloy finished product. The high-silicon aluminum alloy finished product has a tensile strength greater than 300 MPa, a yield strength greater than 130 MPa, an elongation greater than 2.5%, and a hardness greater than 100 HBW.

[0014] The application of the technical solution of the present invention has at least the following beneficial effects: (1) The method for preparing high-strength, high-toughness, and high-wear-resistant semi-solid extrusion high-silicon aluminum alloy products provided by the present invention can produce high-silicon aluminum alloy products with high strength, high toughness, and high wear resistance, solving the problem that existing aluminum alloy materials need further improvement in terms of strength, fracture resistance, and wear resistance; in addition, the prepared high-silicon aluminum alloy products also have the advantages of low coefficient of thermal expansion and good thermal stability. The specific principle is as follows: In the high-silicon aluminum alloy product formulation of this invention in step S1, Al, Si, Cu, and Mg are the main alloying elements. The Fe content in the alloy system is adjusted by adding Mn, thus improving the toughness of the aluminum alloy material. The added Ni, Ti, and Cr elements form aluminum compound dispersed phases in the alloy system. The synergistic effect of these multiple aluminum compound dispersed phases refines the as-cast grains and strengthens the pinning of dislocations, thereby increasing the recrystallization temperature of the alloy material and overcoming the quenching sensitivity problem. This improves the strength and fracture resistance of the aluminum alloy, achieving a high-strength and high-toughness effect in the high-silicon aluminum alloy product. The addition of an aluminum-cerium master alloy not only refines the grains... This process not only improves the Si phase structure in the alloy but also allows it to form new multi-element dispersed phases with elements such as Ni, Mn, Ti, and Cr in the melt, further enhancing the strength and wear resistance of the alloy. Furthermore, using Mn, Ni, and Ti as alloy strengthening elements not only reacts with Fe in the alloy, reducing the appearance of needle-like compounds, but also forms second-phase compounds that are beneficial to the microstructure. These second-phase compounds have high hardness and good roundness, effectively improving the wear resistance of the alloy. Simultaneously, they can act as exogenous nucleation sites to refine the primary Si phase, reducing the hard and brittle phase particles that cause damage during the stress process. Sharp-angle tearing and stress cracking improve the strength of the alloy material; in step S2, smelting ensures complete melting of the raw material components, resulting in a homogeneous aluminum alloy liquid; in step S3, a covering agent is first applied to the surface of the aluminum alloy liquid to form a covering layer to prevent oxidation in the air; a degassing treatment is used to remove impurities from the aluminum alloy liquid; a settling treatment is used to facilitate subsequent cleaning of oxide scale and impurities on the surface of the aluminum alloy liquid, purifying the aluminum alloy liquid; a second application of the covering agent to the surface of the aluminum alloy liquid forms a covering layer, which provides protection when aluminum-cerium master alloy is added to the aluminum alloy liquid for refinement and modification treatment. The process involves several steps: First, a layer is added to prevent the molten aluminum alloy from oxidizing. Second, a refinement modification treatment enhances the modification effect on the Si phase structure in the alloy and passivates the Si phase morphology, thereby reducing sharp-corner tearing and stress concentration during stress, and improving the mechanical properties of the alloy. In step S4, an internal cooling block is added to the molten aluminum alloy to achieve a semi-solid treatment, rapidly cooling the high-temperature molten aluminum alloy to a semi-solid range, becoming a semi-solid slurry, which facilitates the extrusion molding process in step S5. This invention, by synergistically employing semi-solid treatment and extrusion molding, effectively overcomes edge curling and cracking that occur during extrusion molding and improves the appearance of the casting. Furthermore, the addition of suitable alloy components in appropriate composition and dosage, along with the combined use of refinement modification treatment, facilitates a reduction in the thermal expansion coefficient of the high-silicon aluminum alloy product and improves its thermal stability.

[0015] (2) The high silicon aluminum alloy product obtained by the present invention has a tensile strength greater than 300MPa, a yield strength greater than 130MPa, an elongation greater than 2.5%, and a hardness greater than 100HBW, exhibiting high strength, toughness, and wear resistance.

[0016] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart of the preparation method of the high-strength, high-toughness, high-wear-resistant semi-solid extrusion molding high-silicon aluminum alloy product in Example 1.

[0019] Figure 2 This is a schematic diagram of the extrusion molding process in Example 1. Detailed Implementation

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1: See Figure 1 and Figure 2 A method for preparing high-strength, high-toughness, and high-wear-resistant semi-solid extrusion high-silicon aluminum alloy finished products includes: Step S1, ingredient preparation, the raw material components used include: pure aluminum ingot, pure magnesium ingot, industrial crystalline silicon, aluminum-copper master alloy, aluminum-nickel master alloy, aluminum-manganese master alloy, aluminum-titanium master alloy, aluminum-zinc master alloy and aluminum-cerium master alloy; the amount of each raw material component is configured according to the mass percentage of each metal component in the high silicon aluminum alloy finished product. The mass percentages of each metal component in the finished high-silicon aluminum alloy are as follows: The composition comprises 16%~23% (specifically 21%) Si, 1%~2% (specifically 1.5%) Cu, 0.5%~1.5% (specifically 1%) Mg, 0.1%~0.3% (specifically 0.2%) Zn, 0.3%~0.6% (specifically 0.4%) Fe, 0.1%~0.3% (specifically 0.2%) Ti, 0.5%~0.8% (specifically 0.6%) Mn, 0.8%~1% (specifically 1%) Ni, 0.3%~0.9% (specifically 0.6%) Ce, 0.3% impurity elements, and the balance Al; the impurity elements include Cr and Sn. Step S2, Smelting: The prepared industrial crystalline silicon, pure aluminum ingot, aluminum-copper master alloy, aluminum-nickel master alloy, aluminum-manganese master alloy, aluminum-titanium master alloy, aluminum-zinc master alloy and pure magnesium ingot are smelted until completely melted to obtain aluminum alloy liquid; Specifically, the smelting process includes: first, adding 50% to 70% (specifically 50%) of the industrial crystalline silicon by mass to the bottom of the smelting furnace; then adding 60% to 70% (specifically 60%) of the pure aluminum ingot on top of the industrial crystalline silicon to compact and cover it, preventing the industrial crystalline silicon from floating and being oxidized; and then introducing an inert gas or adding a protective flux into the smelting furnace to prevent the surface of the pure aluminum ingot from being oxidized, performing a first smelting process until completely melted; wherein the smelting temperature used in the first smelting process is 750 to 860°C (specifically 840°C). Next, the remaining mass percentage (specifically 40%) of the pure aluminum ingot and the remaining mass percentage (specifically 50%) of the industrial crystalline silicon are pressed into the bottom of the melting furnace to prevent the industrial crystalline silicon from floating and being oxidized, and a second melting process is carried out until it is completely melted; wherein, the melting temperature used in the second melting process is 750~860℃ (specifically 840℃). Then, the aluminum-copper master alloy, the aluminum-nickel master alloy, the aluminum-manganese master alloy, the aluminum-titanium master alloy, and the aluminum-zinc master alloy are added to the melting furnace for a third melting process until they are completely melted; wherein, the melting temperature used in the third melting process is 740~820℃ (specifically 800℃). Finally, the melt in the melting furnace is cooled down, specifically to 740~760℃ (specifically 740℃), and then the pure magnesium ingot is pressed into the melt using a bell jar until it is completely melted to obtain aluminum alloy liquid. Step S3: Refinement and Modification Treatment. A covering agent is sprinkled on the surface of the molten aluminum alloy to form a first covering layer, which is used to prevent the molten aluminum alloy from being oxidized in the air, and the temperature of the molten aluminum alloy is controlled at 740~760℃ (specifically 740℃). Then, the molten aluminum alloy is subjected to degassing treatment and settling treatment in sequence. Subsequently, the oxide scale and impurities on the surface of the molten aluminum alloy are cleaned. Finally, the covering agent is sprinkled on the surface of the molten aluminum alloy to form a second covering layer. Finally, the second covering layer is peeled off, and the aluminum-cerium master alloy is added to the molten aluminum alloy for refinement and modification treatment. Step S4, semi-solid treatment: Before casting, an internal cooling block is added to the aluminum alloy liquid to perform the semi-solid treatment and obtain a semi-solid slurry; wherein, the internal cooling block is a high-silicon aluminum alloy finished product, and its amount is 5% to 15% (specifically 10%) of the mass of the aluminum alloy liquid. Step S5: Extrusion molding process. The semi-solid slurry is poured into a preheated mold, and the pre-made aluminum alloy material is obtained through the extrusion molding process. Step S6: Process the finished product. Open the mold, remove the pre-made aluminum alloy material after cooling and solidification, and process it to obtain the high-silicon aluminum alloy finished product.

[0022] In step S3, the temperature of the refining and modification treatment is 740~760℃ (specifically 740℃), and the time is 20~30min (specifically 30min).

[0023] In step S3, the amount of the covering agent used in the first covering layer accounts for 1% to 1.5% (specifically 1.2%) of the total mass of the aluminum alloy liquid; the amount of the covering agent used in the second covering layer accounts for 0.5% to 1% (specifically 0.6%) of the total mass of the aluminum alloy liquid; the covering agent is a mixture of NaCl and KCl, and the mass ratio of NaCl to KCl is 7:3.

[0024] In step S3, the degassing process includes introducing inert gas into the melting furnace to degas the interior of the molten aluminum alloy. The settling time is 15-20 minutes (specifically 15 minutes).

[0025] In step S4, the stirring speed used in the semi-solid treatment is 1000~1500 rpm (specifically 1200 rpm).

[0026] In step S5, the preheating treatment involves preheating the mold to 260~300℃ (specifically 300℃) to prevent the semi-solid slurry from condensing and solidifying upon contact with the mold, thus ensuring complete filling of the mold cavity.

[0027] The extrusion molding process uses an injection pressure of 120~150MPa (specifically 120MPa), a pressurization time of 80~100ms (specifically 100ms), an extrusion speed of 0.5~0.8m / s (specifically 0.7m / s), and a cycle time of 100~120s (specifically 120s). The pouring temperature of the semi-solid slurry is 650~670℃ (specifically 660℃).

[0028] The high-strength, high-toughness, high-wear-resistant, high-silicon aluminum alloy product prepared using Example 1 has a tensile strength of 330 MPa, a yield strength of 135 MPa, an elongation of 2.8%, and a hardness of 101 HBW.

[0029] Example 2: A method for preparing high-strength, high-toughness, and high-wear-resistant semi-solid extrusion molded high-silicon aluminum alloy products includes: Step S1, ingredient preparation, the raw material components used include: pure aluminum ingot, pure magnesium ingot, industrial crystalline silicon, aluminum-copper master alloy, aluminum-nickel master alloy, aluminum-manganese master alloy, aluminum-titanium master alloy, aluminum-zinc master alloy and aluminum-cerium master alloy; the amount of each raw material component is configured according to the mass percentage of each metal component in the high silicon aluminum alloy finished product. The mass percentages of each metal component in the finished high-silicon aluminum alloy are as follows: The composition comprises 16%~23% (specifically 19%) Si, 1%~2% (specifically 2%) Cu, 0.5%~1.5% (specifically 0.8%) Mg, 0.1%~0.3% (specifically 0.1%) Zn, 0.3%~0.6% (specifically 0.5%) Fe, 0.1%~0.3% (specifically 0.2%) Ti, 0.5%~0.8% (specifically 0.8%) Mn, 0.8%~1% (specifically 0.8%) Ni, 0.3%~0.9% (specifically 0.9%) Ce, 0.3% impurity elements, and the balance Al; the impurity elements include Cr and Sn. Step S2, Smelting: The prepared industrial crystalline silicon, pure aluminum ingot, aluminum-copper master alloy, aluminum-nickel master alloy, aluminum-manganese master alloy, aluminum-titanium master alloy, aluminum-zinc master alloy and pure magnesium ingot are smelted until completely melted to obtain aluminum alloy liquid; Specifically, the smelting process includes: first, adding 50% to 70% (specifically 60%) of the industrial crystalline silicon by mass to the bottom of the smelting furnace; then adding 60% to 70% (specifically 65%) of the pure aluminum ingot on top of the industrial crystalline silicon to compact and cover it, preventing the industrial crystalline silicon from floating and being oxidized; and then introducing an inert gas or adding a protective flux into the smelting furnace to prevent the surface of the pure aluminum ingot from being oxidized, performing a first smelting process until completely melted; wherein the smelting temperature used in the first smelting process is 750 to 860°C (specifically 820°C). Next, the remaining mass percentage (specifically 35%) of the pure aluminum ingot and the remaining mass percentage (specifically 40%) of the industrial crystalline silicon are pressed into the bottom of the melting furnace to prevent the industrial crystalline silicon from floating and being oxidized, and a second melting process is carried out until it is completely melted; wherein, the melting temperature used in the second melting process is 750~860℃ (specifically 820℃). Then, the aluminum-copper master alloy, the aluminum-nickel master alloy, the aluminum-manganese master alloy, the aluminum-titanium master alloy, and the aluminum-zinc master alloy are added to the melting furnace for a third melting process until they are completely melted; wherein, the melting temperature used in the third melting process is 740~820℃ (specifically 820℃). Finally, the melt in the melting furnace is cooled down to 740~760℃ (specifically 750℃), and then the pure magnesium ingot is pressed into the melt using a bell jar until it is completely melted to obtain aluminum alloy liquid. Step S3: Refinement and Modification Treatment. A covering agent is sprinkled on the surface of the molten aluminum alloy to form a first covering layer, which is used to prevent the molten aluminum alloy from being oxidized in the air, and the temperature of the molten aluminum alloy is controlled at 740~760℃ (specifically 750℃). Then, the molten aluminum alloy is subjected to degassing and settling treatment in sequence. Subsequently, the oxide scale and impurities on the surface of the molten aluminum alloy are cleaned. Finally, the covering agent is sprinkled on the surface of the molten aluminum alloy to form a second covering layer. Finally, the second covering layer is peeled off, and the aluminum-cerium master alloy is added to the molten aluminum alloy for refinement and modification treatment. Step S4, semi-solid treatment: Before casting, an internal cooling block is added to the aluminum alloy liquid to perform the semi-solid treatment and obtain a semi-solid slurry; wherein, the internal cooling block is a high-silicon aluminum alloy finished product, and its amount is 5% to 15% (specifically 15%) of the mass of the aluminum alloy liquid. Step S5: Extrusion molding process. The semi-solid slurry is poured into a preheated mold, and the pre-made aluminum alloy material is obtained through the extrusion molding process. Step S6: Process the finished product. Open the mold, remove the pre-made aluminum alloy material after cooling and solidification, and process it to obtain the high-silicon aluminum alloy finished product.

[0030] In step S3, the temperature of the refining and modification treatment is 740~760℃ (specifically 750℃), and the time is 20~30min (specifically 20min).

[0031] In step S3, the amount of the covering agent used in the first covering layer accounts for 1% to 1.5% (specifically 1.3%) of the total mass of the aluminum alloy liquid; the amount of the covering agent used in the second covering layer accounts for 0.5% to 1% (specifically 0.5%) of the total mass of the aluminum alloy liquid; the covering agent is a mixture of NaCl and KCl, and the mass ratio of NaCl to KCl is 7:3.

[0032] In step S3, the degassing process includes introducing inert gas into the melting furnace to degas the interior of the molten aluminum alloy. The settling time is 15-20 minutes (specifically 20 minutes).

[0033] In step S4, the stirring speed used in the semi-solid treatment is 1000~1500 rpm (specifically 1500 rpm).

[0034] In step S5, the preheating treatment involves preheating the temperature of the mold to 260~300℃ (specifically 280℃).

[0035] The extrusion molding process uses an injection pressure of 120~150MPa (specifically 130MPa), a pressurization time of 80~100ms (specifically 90ms), an extrusion speed of 0.5~0.8m / s (specifically 0.6m / s), and a cycle time of 100~120s (specifically 110s). The pouring temperature of the semi-solid slurry is 650~670℃ (specifically 665℃).

[0036] The high-strength, high-toughness, high-wear-resistant, high-silicon aluminum alloy product obtained using Example 2 has a tensile strength of 335 MPa, a yield strength of 132 MPa, an elongation of 2.7%, and a hardness of 103 HBW.

[0037] As shown in Examples 1 and 2, the high-strength, high-toughness, high-wear-resistant, high-silicon aluminum alloy product obtained by this invention has a tensile strength greater than 300 MPa, a yield strength greater than 130 MPa, an elongation greater than 2.5%, and a hardness greater than 100 HBW. In contrast, the high-silicon aluminum alloy (Al-20Si) product prepared using existing casting processes has a tensile strength less than 150 MPa, a yield strength less than 90 MPa, an elongation less than 1%, and a hardness less than 80 HBW. Furthermore, the high-silicon aluminum alloy (Al-20Si) product prepared using traditional steel mold casting has a tensile strength of 135 MPa, a yield strength of 82 MPa, an elongation of 0.9%, and a hardness of 76 HBW. Therefore, compared to existing casting processes and traditional steel mold casting processes, the preparation method used in this invention can produce a high-strength, high-toughness, high-wear-resistant, high-silicon aluminum alloy product with superior performance.

[0038] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the inventive concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for preparing high-strength, high-toughness, and high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy products, characterized in that, include: Step S1, ingredient preparation, the raw material components used include: pure aluminum ingot, pure magnesium ingot, industrial crystalline silicon, aluminum-copper master alloy, aluminum-nickel master alloy, aluminum-manganese master alloy, aluminum-titanium master alloy, aluminum-zinc master alloy and aluminum-cerium master alloy; the amount of each raw material component is configured according to the mass percentage of each metal component in the high silicon aluminum alloy finished product. The mass percentages of each metal component in the finished high-silicon aluminum alloy are as follows: The composition comprises 16%~23% Si, 1%~2% Cu, 0.5%~1.5% Mg, 0.1%~0.3% Zn, 0.3%~0.6% Fe, 0.1%~0.3% Ti, 0.5%~0.8% Mn, 0.8%~1% Ni, 0.3%~0.9% Ce, 0.3% impurity elements, and the balance Al; the impurity elements include Cr and Sn. Step S2, Smelting: The prepared industrial crystalline silicon, pure aluminum ingot, aluminum-copper master alloy, aluminum-nickel master alloy, aluminum-manganese master alloy, aluminum-titanium master alloy, aluminum-zinc master alloy and pure magnesium ingot are smelted until completely melted to obtain aluminum alloy liquid; Step S3: Refinement and modification treatment. A covering agent is sprinkled on the surface of the aluminum alloy liquid to form a first covering layer. The aluminum alloy liquid is then subjected to degassing and settling treatment in sequence. Subsequently, the oxide scale and impurities on the surface of the aluminum alloy liquid are cleaned. Finally, the covering agent is sprinkled on the surface of the aluminum alloy liquid to form a second covering layer. Finally, the second covering layer is peeled off, and the aluminum-cerium master alloy is added to the aluminum alloy liquid for refinement and modification treatment. Step S4, semi-solid treatment: Before casting, add an internal cooling block to the aluminum alloy liquid to perform the semi-solid treatment and obtain a semi-solid slurry. Step S5: Extrusion molding process. The semi-solid slurry is poured into a preheated mold, and the pre-made aluminum alloy material is obtained through the extrusion molding process. Step S6: Process the finished product. Open the mold, remove the pre-made aluminum alloy material after cooling and solidification, and process it to obtain the high-silicon aluminum alloy finished product.

2. The method for preparing the high-strength, high-toughness, high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy product as described in claim 1, characterized in that, In step S2, the smelting includes: first, adding 50% to 70% by mass of the industrial crystalline silicon to the bottom of the smelting furnace, then adding 60% to 70% by mass of the pure aluminum ingot on top of the industrial crystalline silicon, and introducing an inert gas or adding a protective flux into the smelting furnace to carry out the first smelting process until it is completely melted; Next, the remaining mass percentage of the pure aluminum ingot and the remaining mass percentage of the industrial crystalline silicon are pressed into the bottom of the melting furnace for a second melting process until they are completely melted. Then, the aluminum-copper master alloy, the aluminum-nickel master alloy, the aluminum-manganese master alloy, the aluminum-titanium master alloy, and the aluminum-zinc master alloy are added to the melting furnace for a third melting process until they are completely melted. Finally, after cooling the melt in the furnace, the pure magnesium ingot is pressed into the melt until it is completely melted to obtain aluminum alloy liquid. The melting temperature used in the first melting process is 750~860℃; The second smelting process uses a smelting temperature of 750~860℃; The third smelting process uses a smelting temperature of 740~820℃.

3. The method for preparing a high-strength, high-toughness, high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy product as described in claim 2, characterized in that, In step S2, the cooling process involves reducing the temperature of the melt to 740~760°C.

4. The method for preparing the high-strength, high-toughness, high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy product as described in claim 1, characterized in that, In step S3, the temperature of the refining and modification treatment is 740~760℃, and the time is 20~30min.

5. The method for preparing the high-strength, high-toughness, high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy product as described in claim 1, characterized in that, In step S3, the amount of the covering agent used in the first covering layer accounts for 1% to 1.5% of the total mass of the aluminum alloy liquid; the amount of the covering agent used in the second covering layer accounts for 0.5% to 1% of the total mass of the aluminum alloy liquid; the covering agent is a mixture of NaCl and KCl, and the mass ratio of NaCl to KCl is 7:

3.

6. The method for preparing the high-strength, high-toughness, high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy product as described in claim 1, characterized in that, In step S3, the degassing process includes introducing inert gas into the melting furnace to degas the interior of the molten aluminum alloy. The settling time for the static treatment is 15-20 minutes.

7. The method for preparing the high-strength, high-toughness, high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy product as described in claim 1, characterized in that, In step S4, the internal cooling block is a high-silicon aluminum alloy finished product, and its amount is 5% to 15% of the mass of the aluminum alloy liquid; the stirring speed used in the semi-solid treatment is 1000 to 1500 rpm.

8. The method for preparing the high-strength, high-toughness, high-wear-resistant semi-solid extrusion-molded high-silicon aluminum alloy product as described in claim 1, characterized in that, In step S5, the preheating treatment involves preheating the mold to 260~300℃.

9. The method for preparing a high-strength, high-toughness, high-wear-resistant semi-solid extruded high-silicon aluminum alloy product as described in any one of claims 1 to 8, characterized in that, The extrusion molding process uses an injection pressure of 120~150MPa, a pressurization time of 80~100ms, an extrusion speed of 0.5~0.8m / s, and a cycle time of 100~120s. The pouring temperature of the semi-solid slurry is 650~670℃.

10. A high-strength, high-toughness, and high-wear-resistant semi-solid extruded high-silicon aluminum alloy product, characterized in that, The high-strength, high-toughness, and high-wear-resistant semi-solid extrusion molding high-silicon aluminum alloy product as described in claim 9 was used to prepare the product. The high-silicon aluminum alloy finished product has a tensile strength greater than 300 MPa, a yield strength greater than 130 MPa, an elongation greater than 2.5%, and a hardness greater than 100 HBW.

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