High-toughness AlSi10MgMn alloy and preparation method thereof

Abstract

The application discloses a kind of high tough AlSi10MgMn alloy and preparation method thereof, the composition of high tough AlSi10MgMn alloy includes: silicon 8.0~11.0%, magnesium 0.17~0.60%, manganese 0.2~0.6%, titanium 0.08~0.40%, boron 0.004~0.018%, strontium 0.3~0.6%, rare earth metal 0.1~0.3%, unavoidable impurity less than 1%, the balance is aluminum, the aforementioned percentage is mass percentage.The high tough AlSi10MgMn alloy of the application, surface neat, the mechanical properties such as tensile strength and elongation are significantly improved;Alloy grain is fine, dispersion uniform, no aggregation, no burning loss;Preparation method is simple and easy to operate.

Description

Technical Field

[0001] This invention relates to a high-strength and high-toughness AlSi10MgMn alloy and its preparation method, belonging to the technical field of AlSi10MgMn alloys. Background Technology

[0002] Aluminum alloys are among the most widely used non-ferrous metal structural materials in industry, with extensive applications in aviation, aerospace, automotive, machinery manufacturing, shipbuilding, and chemical industries. With the rapid development of science and technology and the industrial economy in recent years, the demand for aluminum alloys has been increasing, leading to more in-depth research on them.

[0003] With "energy conservation and environmental protection" becoming increasingly important topics, lightweighting is being widely applied in the automotive industry, improving handling while also achieving excellent fuel economy. A car's fuel consumption primarily depends on its engine displacement and total mass. While maintaining or even optimizing the overall quality, performance, and cost of the vehicle, reducing its weight can increase power output, reduce noise, improve handling and reliability, increase speed, reduce fuel consumption, decrease emissions, and enhance safety. The car body accounts for approximately 30% of its total mass, and under unloaded conditions, about 70% of fuel consumption is attributed to the car body's weight. Therefore, a lighter car body significantly benefits overall fuel economy, vehicle control stability, and collision safety.

[0004] Currently, due to the needs of environmental protection and energy conservation, lightweighting of automobiles has become a global trend in automotive development. One way to achieve lightweighting is by selecting lightweight materials. Several new aluminum alloys have emerged, with AlSiMgMn alloy being one of them. Due to its good casting performance and excellent mechanical, physical, and corrosion resistance properties, it has received widespread attention and application. However, the ductility of AlSi10MgMn alloy is currently poor, and its strength and toughness still need further improvement. Summary of the Invention

[0005] This invention provides a high-strength and high-toughness AlSi10MgMn alloy and its preparation method, which significantly improves the strength and toughness of the alloy. The resulting alloy has a clean surface, no pinholes, fine and uniformly dispersed grains, no agglomeration, no burn-off, and no obvious impurities.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A high-strength and high-toughness AlSi10MgMn alloy comprises: silicon 8.0-11.0%, magnesium 0.17-0.60%, manganese 0.2-0.6%, titanium 0.08-0.40%, boron 0.004-0.018%, strontium 0.3-0.6%, rare earth metals 0.1-0.3%, unavoidable impurities less than 1%, and the balance being aluminum. All percentages are by mass.

[0008] To further improve the physical and mechanical properties of the alloy, the rare earth metal is at least one of neodymium or yttrium. More preferably, the rare earth metal is a mixture of neodymium and yttrium in a mass ratio of (2.5 to 3.5):1.

[0009] The inventors discovered that specific amounts of titanium, boron, and strontium have a significant refining and modification effect on AlSi10MgMn alloys, and also improve strength to a certain extent, but slightly reduce elongation. Furthermore, by adding specific amounts of neodymium and yttrium to the base of titanium, boron, and strontium, the dendrites are further refined, the orientation becomes more ordered and spheroidized, the strength and toughness are significantly improved, and the matrix is ​​also purified.

[0010] The specific amounts of titanium, boron, strontium, neodymium, and yttrium used in this application have a significant synergistic effect on AlSi10MgMn.

[0011] For ease of preparation, titanium was added in the form of AlTi5B1; strontium was added in the form of aluminum strontium 10; neodymium was added in the form of aluminum neodymium alloy ALNd30; and yttrium was added in the form of aluminum yttrium alloy AL-Y 10.

[0012] The above-mentioned high-strength and high-toughness AlSi10MgMn alloy is prepared by a medium-frequency furnace, including the following steps:

[0013] 1) Put metallic silicon into the furnace, then add molten aluminum at a temperature of 650-750℃, raise the temperature to 1200-1300℃, and refine with argon gas through a graphite tube for 5-10 minutes. After refining, lower the temperature to 1000-1100℃, add metallic manganese, and stir with argon gas for 30 minutes.

[0014] Alternatively, 1) put metallic silicon into the furnace, then add molten aluminum at a temperature of 650-750℃, raise the temperature to 800-850℃, and refine with argon gas through a graphite tube for 5-10 minutes. After refining, lower the temperature to 750-800℃, add aluminum-manganese alloy, and stir with argon gas for 30 minutes.

[0015] That is, there are two ways to add manganese in step 1), and the refining conditions and addition temperature are also different.

[0016] 2) Cool the temperature to 780-800℃, add magnesium ingots, and stir with argon gas for 5-10 minutes;

[0017] 3) Add AlTi5B1 and aluminum strontium 10 at a controlled temperature of 780-800℃, stir with argon gas for 10-15 minutes, then add rare earth metal raw materials and continue stirring with argon gas at 780-800℃ for 30-40 minutes, then remove the slag.

[0018] 4) Let stand for 10-15 minutes, reduce the temperature to 700-710℃, pour, cool, and obtain AlSi10MgMn alloy ingot.

[0019] The AlSi10MgMn alloy ingots obtained by the above method have a clean surface and significantly improved mechanical properties such as tensile strength and elongation.

[0020] Temperature control in step 1) helps reduce magnesium burn-off and improve product quality. The introduction of argon gas in step 2) helps ensure more uniform distribution of various added elements.

[0021] In step 1) above, the aluminum-manganese alloy is aluminum-manganese 10 or aluminum-manganese 20; the metallic manganese is manganese flakes or manganese powder, and the composition of the metallic manganese is: Si≤0.08%, Fe≤0.08%, total other impurities≤0.3%, and Mn balance.

[0022] In step 1) above, the purity of the molten aluminum is not less than 99.7%; the purity of the magnesium ingot is not less than 99.9%.

[0023] In steps 1-3 above, the argon pressure is 0.01-0.03 MPa.

[0024] Argon gas is blown in through a graphite tube during each step.

[0025] Unless otherwise specified in this application, all percentages are percentages by mass.

[0026] Any techniques not mentioned in this invention are based on existing technologies.

[0027] The high-strength and high-toughness AlSi10MgMn alloy of this invention has a clean surface and significantly improved mechanical properties such as tensile strength and elongation; the alloy grains are fine, uniformly dispersed, without agglomeration or burn-off; and the preparation method is simple and easy to operate. Attached Figure Description

[0028] Figure 1 The image shows the metallographic structure of the AlSi10MgMn alloy obtained in Example 1 of this invention.

[0029] Figure 2 The image shows the metallographic structure of the AlSi10MgMn alloy obtained in Example 4 of this invention.

[0030] Figure 3 The image shows the metallographic structure of the AlSi10MgMn alloy obtained in Comparative Example 1 of this invention.

[0031] Figure 4 The image shows the metallographic structure of the AlSi10MgMn alloy obtained in Comparative Example 2 of this invention.

[0032] Figure 5 The metallographic image of the AlSi10MgMn alloy obtained in Comparative Example 3 of this invention is shown. Detailed Implementation

[0033] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0034] Example 1

[0035] A high-strength and high-toughness AlSi10MgMn alloy comprises: Si 9.5%, Mg 0.50%, Mn 0.4%, Ti 0.2%, boron 0.009%, strontium 0.4%, neodymium 0.12%, yttrium 0.04%, unavoidable impurities less than 1%, and the balance being Al. All the aforementioned percentages are mass percentages.

[0036] The preparation of the above-mentioned high-strength and high-toughness AlSi10MgMn alloy was carried out using a 3-ton medium-frequency furnace, and included the following steps:

[0037] 1) Put metallic silicon (553 metallic silicon, Xinjiang Western Hesheng Silicon Industry) into the furnace, then add molten aluminum (purity ≥99.7%) at a temperature of 700-710℃, raise the temperature to 820-830℃, and refine with argon gas through a graphite tube for 8 minutes. After refining, lower the temperature to 780-790℃, add aluminum manganese alloy 10 (grade AlMn10, impurity content ≤0.01%, Shandong Yunxin Aluminum Industry Technology Co., Ltd.), and stir with argon gas for 30 minutes.

[0038] 2) Cool the temperature to 780-800℃, add magnesium ingots (purity ≥99.9%), blow argon gas and stir for 8 minutes until the magnesium ingots are completely melted;

[0039] 3) Control the temperature at 790-800℃ and add AlTi5B1 (grade AlTi5B1, impurity content ≤0.01%, Shenzhen Ruihongjia Metal Materials Co., Ltd.) and aluminum strontium 10 (grade AlSr10, impurity content ≤0.2%, Shanghai Xincheng Aluminum Co., Ltd.). After stirring with argon for 15 minutes, add rare earth metal raw materials (neodymium is added in the form of aluminum-neodymium alloy ALNd30, brand: Hengyude, first grade, impurity content 0.4%; yttrium is added in the form of aluminum-yttrium alloy AL-Y 10, brand: ZD, Fe<0.05, Si<0.03). Continue stirring with argon at 790-800℃ for 30-40 minutes, and remove slag. In steps 1) to 3), the argon pressure in the furnace is maintained at about 0.02 MPa.

[0040] 4) Let stand for 15 minutes, raise the temperature to 800-810℃, pour, and cool to obtain a high-strength and tough AlSi10MgMn alloy ingot with a clean surface and no pinholes. Its metallographic image is as follows. Figure 1 As shown, the alloy grains are fine, uniformly dispersed, without agglomeration, burn-off, or obvious impurities.

[0041] Example 2

[0042] A high-strength and high-toughness AlSi10MgMn alloy comprises: Si 10.2%, Mg 0.30%, Mn 0.6%, Ti 0.2%, boron 0.009%, strontium 0.6%, neodymium 0.12%, yttrium 0.04%, unavoidable impurities less than 1%, and the balance being Al. All percentages are by mass. The preparation method follows Example 1. The resulting high-strength and high-toughness AlSi10MgMn alloy ingot has a clean surface, is free of pinholes, has fine and uniformly dispersed grains, and exhibits no agglomeration or burn-off.

[0043] Example 3

[0044] A high-strength and high-toughness AlSi10MgMn alloy comprises: Si 9.5%, Mg 0.50%, Mn 0.4%, Ti 0.2%, boron 0.009%, strontium 0.4%, neodymium 0.12%, unavoidable impurities less than 1%, and the balance being Al. All percentages are by mass. The preparation method differs from Example 1 in that aluminum-yttrium alloy AL-Y10 is not added; all other components are the same as in Example 1. The resulting high-strength and high-toughness AlSi10MgMn alloy ingot has a clean surface, no pinholes, fine and uniformly dispersed grains, no agglomeration, and no burn-off.

[0045] Example 4

[0046] A high-strength and high-toughness AlSi10MgMn alloy comprises: Si 9.5%, Mg 0.50%, Mn 0.4%, Ti 0.2%, boron 0.009%, strontium 0.4%, yttrium 0.04%, unavoidable impurities less than 1%, and the balance being Al. All percentages are by mass. The preparation method differs from Example 1 in that the aluminum-neodymium alloy ALNd30 is not added; all other components are the same as in Example 1. The resulting high-strength and high-toughness AlSi10MgMn alloy ingot has a clean surface and is free of pinholes. The metallographic image of the obtained alloy is shown below. Figure 2 As shown, it can be seen that the uniformity is good, there is no burn damage, and there are no obvious impurities, but the fineness is obviously not as good as that of Example 1.

[0047] Comparative Example 1

[0048] An AlSi10MgMn alloy comprises: 9.5% Si, 0.50% Mg, 0.4% Mn, less than 1% unavoidable impurities, and the balance being Al. All percentages are by mass.

[0049] The preparation of the above AlSi10MgMn alloy was carried out using a 3-ton medium-frequency furnace, and included the following steps:

[0050] 1) Put metallic silicon (553 metallic silicon, Xinjiang Western Hesheng Silicon Industry) into the furnace, then add molten aluminum (purity ≥99.7%) at a temperature of 700-710℃, raise the temperature to 820-830℃, and refine with argon gas through a graphite tube for 8 minutes. After refining, lower the temperature to 780-790℃, add aluminum manganese alloy 10 (grade AlMn10, impurity content ≤0.01%, Shandong Yunxin Aluminum Industry Technology Co., Ltd.), and stir with argon gas for 30 minutes.

[0051] 2) Cool the temperature to 780-800℃, add magnesium ingots (purity ≥99.9%), stir with argon gas for 8 minutes until all magnesium ingots are melted; remove slag; in steps 1) to 2), the argon gas pressure in the furnace is maintained at about 0.02 MPa;

[0052] 3) Let stand for 15 minutes, raise the temperature to 800-810℃, pour, and cool to obtain AlSi10MgMn alloy ingots, the metallographic diagram of which is shown below. Figure 3 As shown, it exhibits a large dendritic structure with disordered grain orientation.

[0053] Comparative Example 2

[0054] An AlSi10MgMn alloy comprises: Si 9.5%, Mg 0.50%, Mn 0.4%, Ti 0.2%, boron 0.009%, unavoidable impurities less than 1%, and the balance being Al. All percentages are by mass.

[0055] The preparation of the above AlSi10MgMn alloy was carried out using a 3-ton medium-frequency furnace, and included the following steps:

[0056] 1) Put metallic silicon (553 metallic silicon, Xinjiang Western Hesheng Silicon Industry) into the furnace, then add molten aluminum (purity ≥99.7%) at a temperature of 700-710℃, raise the temperature to 820-830℃, and refine with argon gas through a graphite tube for 8 minutes. After refining, lower the temperature to 780-790℃, add aluminum manganese alloy 10 (grade AlMn10, impurity content ≤0.01%, Shandong Yunxin Aluminum Industry Technology Co., Ltd.), and stir with argon gas for 30 minutes.

[0057] 2) Cool the temperature to 780-800℃, add magnesium ingots (purity ≥99.9%), blow argon gas and stir for 8 minutes until the magnesium ingots are completely melted;

[0058] 3) Add AlTi5B1 (grade AlTi5B1, impurity content ≤0.01%, Shenzhen Ruihongjia Metal Materials Co., Ltd.) at a controlled temperature of 790~800℃, stir with argon gas for 15 minutes, and then remove the slag; in steps 1) to 3), the argon gas pressure in the furnace is maintained at about 0.02Mpa.

[0059] 4) Let stand for 15 minutes, raise the temperature to 800-810℃, pour, and cool to obtain AlSi10MgMn alloy ingots, the metallographic diagram of which is shown below. Figure 4 As shown, there is a significant refinement compared to Comparative Example 1.

[0060] Comparative Example 3

[0061] An AlSi10MgMn alloy comprises: Si 9.5%, Mg 0.50%, Mn 0.4%, Ti 0.2%, boron 0.009%, strontium 0.4%, unavoidable impurities less than 1%, and the balance being Al. All percentages are by mass.

[0062] The preparation of the above AlSi10MgMn alloy was carried out using a 3-ton medium-frequency furnace, and included the following steps:

[0063] 1) Put metallic silicon (553 metallic silicon, Xinjiang Western Hesheng Silicon Industry) into the furnace, then add molten aluminum (purity ≥99.7%) at a temperature of 700-710℃, raise the temperature to 820-830℃, and refine with argon gas through a graphite tube for 8 minutes. After refining, lower the temperature to 780-790℃, add aluminum manganese alloy 10 (grade AlMn10, impurity content ≤0.01%, Shandong Yunxin Aluminum Industry Technology Co., Ltd.), and stir with argon gas for 30 minutes.

[0064] 2) Cool the temperature to 780-800℃, add magnesium ingots (purity ≥99.9%), blow argon gas and stir for 8 minutes until the magnesium ingots are completely melted;

[0065] 3) Add AlTi5B1 (grade AlTi5B1, impurity content ≤0.01%, Shenzhen Ruihongjia Metal Materials Co., Ltd.) and aluminum strontium 10 (grade AlSr10, impurity content ≤0.2%, Shanghai Xincheng Aluminum Co., Ltd.) at a controlled temperature of 790-800℃. Stir with argon gas for 15 minutes, then remove the slag. In steps 1) to 3), maintain the argon pressure in the furnace at around 0.02 MPa.

[0066] 4) Let stand for 15 minutes, raise the temperature to 800-810℃, pour, and cool to obtain AlSi10MgMn alloy ingots, the metallographic diagram of which is shown below. Figure 5As shown, compared to Comparative Example 2, there is a significant refinement, but no spheroidization. It is significantly worse than Example 1. It can be seen that Example 1, through the refinement and modification of titanium, boron, strontium, and rare earth metals, has significantly refined dendrites, ordered orientation, spheroidization, and uniform distribution, and produced more crystal nuclei.

[0067] Table 1. Evaluation of the mechanical properties of AlSi10MgMn alloys obtained in each example.

[0068] Example 1 395 16.8 Example 2 392 16.3 Example 3 352 3.8 Example 4 332 3.1 Comparative Example 1 308 2.5 Comparative Example 2 322 2.3 Comparative Example 3 328 2.0

Claims

1. A high tough AlSi10MgMn alloy, characterized in that: Its composition includes: silicon 8.0~11.0%, magnesium 0.17~0.60%, manganese 0.2~0.6%, titanium 0.08~0.40%, boron 0.004~0.018%, strontium 0.3~0.6%, rare earth metals 0.1~0.3%, unavoidable impurities less than 1%, and the balance being aluminum. All the above percentages are by mass. Rare earth metals are mixtures of neodymium and yttrium in a mass ratio of (2.5~3.5):1; The preparation method of high-strength and high-toughness AlSi10MgMn alloy, using a medium-frequency furnace, includes the following steps: 1) Put metallic silicon into the furnace, then add molten aluminum at a temperature of 650-750℃, raise the temperature to 800-850℃, and refine with argon gas through a graphite tube for 5-10 minutes. After refining, lower the temperature to 750-800℃, add aluminum-manganese alloy, and stir with argon gas for 20-30 minutes. 2) Cool the temperature to 780-800℃, add magnesium ingots, and stir with argon gas for 5-10 minutes; 3) Add AlTi5B1 and aluminum strontium 10 at a controlled temperature of 780-800℃, stir with argon gas for 10-15 minutes, then add rare earth metal raw materials and continue stirring with argon gas at 780-800℃ for 30-40 minutes, then remove the slag. 4) Let stand for 10-15 minutes, heat to 800~820℃, pour, cool, and obtain AlSi10MgMn alloy ingot.

2. The high-strength and high-toughness AlSi10MgMn alloy as described in claim 1, characterized in that: Neodymium was added in the form of an aluminum-neodymium alloy, AlNd30.

3. The high-strength and high-toughness AlSi10MgMn alloy as described in claim 1 or 2, characterized in that: Yttrium was added in the form of an aluminum-yttrium alloy, Al-Y10.

4. The high-strength and high-toughness AlSi10MgMn alloy as described in claim 1 or 2, characterized in that: In step 1), the aluminum-manganese alloy is aluminum-manganese 10 or aluminum-manganese 20.

5. The high-strength and high-toughness AlSi10MgMn alloy as described in claim 1 or 2, characterized in that: In step 1), the purity of the molten aluminum is not less than 99.7%; in step 2), the purity of the magnesium ingot is not less than 99.9%.

6. The high-strength and high-toughness AlSi10MgMn alloy as described in claim 1 or 2, characterized in that: In steps 1) to 3), the argon pressure is 0.01-0.03 MPa.

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