Process for preparing aluminum-silicon alloy by villiaumite method

Abstract

The invention relates to the technical field of aluminum-silicon alloys, and provides a process for preparing an aluminum-silicon alloy by a villiaumite method, which comprises the following steps: S1, melting 85-95% by mass of aluminum ingot to obtain molten aluminum; s2, 40%-60% by mass of potassium fluosilicate is added into the molten aluminum for a first reaction, then the remaining mass of potassium fluosilicate is added for a second reaction, a modifier is added for mixing, the remaining mass of aluminum ingot is added for continuous mixing, casting molding is conducted, and aluminum-silicon alloy is obtained; the modifier comprises the following components in parts by weight: 5-8 parts of Al-Sr alloy, 1-4 parts of titanium aluminum carbide and 0.5-1 part of yttrium oxide. According to the technical scheme, the problem that the strength and toughness of the aluminum-silicon alloy prepared through a villiaumite method in the related technology are poor is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum-silicon alloys, and in particular to a process for preparing aluminum-silicon alloys by a fluoride salt method. Background Art

[0002] Aluminum-silicon alloys have been widely used in many industries such as aerospace, automobile manufacturing, and electronic equipment due to their excellent comprehensive properties, such as low density, high specific strength, good casting performance, and corrosion resistance. In order to meet the ever-increasing industrial needs, it is crucial to explore efficient and high-quality preparation methods. As one of the methods for preparing aluminum-silicon alloys, the fluoride salt method has attracted the attention of many researchers in recent years. However, in actual production, when aluminum-silicon alloys are prepared by the fluoride salt method, due to the complexity of the reaction between fluoride salts and raw materials, there are differences in reaction rate and degree in different regions, which can easily lead to uneven distribution of elements such as silicon in the alloy and local agglomeration, which will greatly affect the mechanical properties of the alloy and reduce the strength and toughness of the aluminum-silicon alloy. Summary of the invention

[0003] The present invention proposes a process for preparing aluminum-silicon alloy by the fluoride salt method, which solves the problem of poor strength and toughness of aluminum-silicon alloy prepared by the fluoride salt method in the related art.

[0004] The technical solution of the present invention is as follows: The present invention provides a process for preparing aluminum-silicon alloy by a fluoride salt method, comprising the following steps: S1, first take 85%~95% of the mass of aluminum ingots to melt and obtain aluminum liquid; S2, first adding 40% to 60% by weight of potassium fluorosilicate to the aluminum liquid for a first reaction, then adding the remaining weight of potassium fluorosilicate for a second reaction, adding a modifier for mixing, adding the remaining weight of aluminum ingots for further mixing, and casting to obtain an aluminum-silicon alloy; The modifier comprises the following components in parts by weight: 5-8 parts of Al-Sr alloy, 1-4 parts of aluminum titanium carbide, and 0.5-1 parts of yttrium oxide.

[0005] As a further technical solution, slag removal is performed before the casting.

[0006] As a further technical solution, the amount of the modifier added is 0.8% to 1.2% of the mass of the aluminum ingot.

[0007] As a further technical solution, the mass ratio of the Al-Sr alloy, aluminum titanium carbide and yttrium oxide is 6~7:3:0.8.

[0008] In the present invention, the mass ratio of the components of the modifier, namely, the Al-Sr alloy, aluminum titanium carbide and yttrium oxide, is adjusted to 6-7:3:0.8, thereby further improving the strength and toughness of the aluminum silicon alloy.

[0009] As a further technical solution, the mass ratio of the aluminum ingot to potassium fluorosilicate is 100:25~35.

[0010] As a further technical solution, the temperature of the aluminum liquid is 800-850°C.

[0011] As a further technical solution, the time for the first reaction and the second reaction are each independently 15 to 20 minutes.

[0012] As a further technical solution, the acid liquid on the surface of the aluminum liquid is removed after both the first reaction and the second reaction.

[0013] As a further technical solution, the casting temperature is 750-780°C.

[0014] As a further technical solution, the aluminum titanium carbide is cerium oxide modified aluminum titanium carbide.

[0015] As a further technical solution, the preparation method of cerium oxide modified aluminum titanium carbide comprises the following steps: subjecting a cerium source, a precipitant and aluminum titanium carbide to a hydrothermal reaction, and drying to obtain cerium oxide modified aluminum titanium carbide; The cerium source is a cerium salt solution with a mass concentration of 0.5% to 0.8%; the cerium salt solution includes cerium nitrate hexahydrate; The mass ratio of the cerium source, the precipitant and the aluminum titanium carbide is 1-2:0.2:1.

[0016] In the present invention, aluminum titanium carbide is surface-modified by cerium oxide to promote the dispersion of aluminum carbide in aluminum liquid, thereby further improving the strength and toughness of the aluminum silicon alloy.

[0017] The working principle and beneficial effects of the present invention are: In the present invention, the aluminum silicon alloy is prepared by the fluorine salt method, potassium fluorosilicate is added step by step in the process, and Al-Sr alloy, aluminum titanium carbide and yttrium oxide are introduced as modifiers of the aluminum silicon alloy, which significantly improves the strength and toughness of the aluminum silicon alloy by refining the grains of the aluminum silicon alloy, strengthening the aluminum silicon alloy matrix and forming a fine and evenly distributed strengthening phase. DETAILED DESCRIPTION

[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] In the following examples and comparative examples, the titanium aluminum carbide is Ti3AlC2, and the particle size is 5 μm; The particle size of titanium carbide is 5 μm; The particle size of yttrium oxide is 50 nm; The grade of Al-Sr alloy is Al-Sr10; The purity of aluminum ingots is 99.99%.

[0020] Example 1 The process for preparing aluminum-silicon alloy by fluoride salt method comprises the following steps: S1, first take 85% of the aluminum ingot by mass and melt it to obtain aluminum liquid, and keep the temperature of the aluminum liquid at 800℃; S2, first add 40% by weight of potassium fluorosilicate to the aluminum liquid to react for 15 minutes, after the reaction is completed, pour out the acid liquid on the surface of the aluminum liquid, then add the remaining weight of potassium fluorosilicate to react for 15 minutes, after the reaction is completed, pour out the acid liquid on the surface of the aluminum liquid, remove the slag, add a modifier to mix, add the remaining weight of aluminum ingot to mix, remove the slag, and cast at 750° C. to obtain an aluminum-silicon alloy; Among them, the mass ratio of aluminum ingot and potassium fluorosilicate is 100:25, the added amount of the modifier is 0.8% of the mass of the aluminum ingot, and the modifier includes the following components in parts by weight: 5 parts of Al-Sr alloy, 1 part of aluminum titanium carbide, and 0.5 parts of yttrium oxide.

[0021] Example 2 The process for preparing aluminum-silicon alloy by fluoride salt method comprises the following steps: S1. First, 95% of the mass of aluminum ingots are melted to obtain aluminum liquid, and the temperature of the aluminum liquid is maintained at 850°C; S2, first add 60% of the mass of potassium fluorosilicate to the aluminum liquid to react for 20 minutes, pour out the acid on the surface of the aluminum liquid after the reaction, then add the remaining mass of potassium fluorosilicate to react for 20 minutes, pour out the acid on the surface of the aluminum liquid after the reaction, remove the slag, add a modifier to mix, add the remaining mass of aluminum ingot to mix, remove the slag, and cast at 780° C. to obtain an aluminum-silicon alloy; Among them, the mass ratio of aluminum ingot and potassium fluorosilicate is 100:35, the added amount of the modifier is 1.2% of the mass of the aluminum ingot, and the modifier includes the following components in parts by weight: 8 parts of Al-Sr alloy, 4 parts of aluminum titanium carbide, and 1 part of yttrium oxide.

[0022] Example 3 The process for preparing aluminum-silicon alloy by fluoride salt method comprises the following steps: S1, first take 90% of the mass of aluminum ingots to melt to obtain aluminum liquid, and keep the temperature of the aluminum liquid at 830℃; S2, first add 50% of the mass of potassium fluorosilicate to the aluminum liquid to react for 16 minutes, pour out the acid on the surface of the aluminum liquid after the reaction, then add the remaining mass of potassium fluorosilicate to react for 18 minutes, pour out the acid on the surface of the aluminum liquid after the reaction, remove the slag, add a modifier to mix, add the remaining mass of aluminum ingot to mix, remove the slag, and cast at 760° C. to obtain an aluminum-silicon alloy; Among them, the mass ratio of aluminum ingot and potassium fluorosilicate is 100:30, the added amount of the modifier is 1% of the mass of the aluminum ingot, and the modifier includes the following components in parts by weight: 5 parts of Al-Sr alloy, 3 parts of aluminum titanium carbide, and 0.8 parts of yttrium oxide.

[0023] Example 4 The only difference between this embodiment and embodiment 3 is that the modifier includes the following components in parts by weight: 8 parts of Al-Sr alloy, 3 parts of aluminum titanium carbide, and 0.8 parts of yttrium oxide.

[0024] Example 5 The only difference between this embodiment and embodiment 3 is that the modifier includes the following components in parts by weight: 6 parts of Al-Sr alloy, 3 parts of aluminum titanium carbide, and 0.8 parts of yttrium oxide.

[0025] Example 6 The only difference between this embodiment and embodiment 3 is that the modifier includes the following components in parts by weight: 7 parts of Al-Sr alloy, 3 parts of aluminum titanium carbide, and 0.8 parts of yttrium oxide.

[0026] Example 7 The difference between this embodiment and embodiment 6 is that aluminum titanium carbide is replaced with cerium oxide modified aluminum titanium carbide; The preparation method of cerium oxide modified aluminum titanium carbide comprises the following steps: subjecting a cerium source, urea and aluminum titanium carbide to a hydrothermal reaction, and drying to obtain cerium oxide modified aluminum titanium carbide; The cerium source is a cerium nitrate hexahydrate aqueous solution with a mass concentration of 0.8%; The mass ratio of the cerium nitrate hexahydrate aqueous solution, urea and aluminum titanium carbide is 1:0.2:1.

[0027] Example 8 The difference between this embodiment and embodiment 6 is that aluminum titanium carbide is replaced with cerium oxide modified aluminum titanium carbide; The preparation method of cerium oxide modified aluminum titanium carbide comprises the following steps: subjecting a cerium source, urea and aluminum titanium carbide to a hydrothermal reaction, and drying to obtain cerium oxide modified aluminum titanium carbide; The cerium source is a cerium nitrate hexahydrate aqueous solution with a mass concentration of 0.5%; The mass ratio of the cerium nitrate hexahydrate aqueous solution, urea and aluminum titanium carbide is 2:0.2:1.

[0028] Comparative Example 1 The only difference between this comparative example and Example 3 is that no modifier is added in step S2.

[0029] Comparative Example 2 The only difference between this comparative example and Example 3 is that in step S2, the modifier includes the following components in parts by weight: 5 parts of Al-Sr alloy and 3 parts of aluminum titanium carbide.

[0030] Comparative Example 3 The only difference between this comparative example and Example 3 is that in step S2, the modifier includes the following components in parts by weight: 5 parts of Al-Sr alloy and 0.8 parts of yttrium oxide.

[0031] Comparative Example 4 The only difference between this comparative example and Example 3 is that in step S2, the modifier includes the following components in parts by weight: 3 parts of aluminum titanium carbide and 0.8 parts of yttrium oxide.

[0032] Comparative Example 5 The difference between this comparative example and Example 3 is that aluminum titanium carbide is replaced by titanium carbide.

[0033] According to the standard GB / T 228.1-2021 "Tensile test of metallic materials Part 1: Room temperature test method", the yield strength and elongation of the aluminum silicon alloys prepared in Examples 1 to 8 and Comparative Examples 1 to 5 were tested respectively, and the test results are shown in Table 1 below.

[0034] Table 1 Test results of aluminum silicon alloy properties

[0035] Compared with comparative examples 1 to 5, the yield strength and elongation of the aluminum-silicon alloys prepared in embodiments 1 to 8 are higher, indicating that the aluminum-silicon alloys are prepared by the fluoride salt method and the Al-Sr alloy, aluminum titanium carbide and yttrium oxide are introduced as modifiers of the aluminum-silicon alloy, which significantly improves the strength and toughness of the aluminum-silicon alloy.

[0036] Compared with Examples 3 to 4, the yield strength and elongation of the aluminum-silicon alloy prepared in Examples 5 to 6 are higher, indicating that the mass ratio of the modifier components Al-Sr alloy, aluminum titanium carbide and yttrium oxide is adjusted to 6 to 7:3:0.8, which further improves the strength and toughness of the aluminum-silicon alloy.

[0037] Compared with Example 6, the yield strength and elongation of the aluminum-silicon alloys prepared in Examples 7-8 are higher, indicating that the strength and toughness of the aluminum-silicon alloys are further improved by surface modification of aluminum titanium carbide with cerium oxide.

[0038] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A process for preparing aluminum silicon alloy by fluoride salt method, characterized in that: The following steps are involved: S1, first take 85%~95% of the mass of aluminum ingots to melt and obtain aluminum liquid; S2, first adding 40% to 60% by weight of potassium fluorosilicate to the aluminum liquid for a first reaction, then adding the remaining weight of potassium fluorosilicate for a second reaction, adding a modifier for mixing, adding the remaining weight of aluminum ingots for further mixing, and casting to obtain an aluminum-silicon alloy; The modifier comprises the following components in parts by weight: 5-8 parts of Al-Sr alloy, 1-4 parts of aluminum titanium carbide, and 0.5-1 parts of yttrium oxide.

2. The process for preparing aluminum-silicon alloy by a fluoride salt method according to claim 1, characterized in that: The amount of the modifier added is 0.8% to 1.2% of the mass of the aluminum ingot.

3. The process for preparing aluminum-silicon alloy by a fluoride salt method according to claim 1, characterized in that: The mass ratio of the Al-Sr alloy, aluminum titanium carbide and yttrium oxide is 6-7:3:0.

8.

4. The process for preparing aluminum-silicon alloy by a fluoride salt method according to claim 1, characterized in that: The mass ratio of the aluminum ingot to potassium fluorosilicate is 100:25-35.

5. The process for preparing aluminum-silicon alloy by fluoride salt method according to claim 1, characterized in that: The temperature of the aluminum liquid is 800-850°C.

6. The process for preparing aluminum-silicon alloy by fluoride salt method according to claim 1, characterized in that: The time of the first reaction and the second reaction is independently 15 to 20 minutes.

7. The process for preparing aluminum-silicon alloy by fluoride salt method according to claim 1, characterized in that: The acid liquid on the surface of the aluminum liquid is removed after both the first reaction and the second reaction.

8. The process for preparing aluminum silicon alloy by fluoride salt method according to claim 1, characterized in that: The casting temperature is 750-780°C.

9. The process for preparing aluminum-silicon alloy by fluoride salt method according to claim 3, characterized in that: The aluminum titanium carbide is cerium oxide modified aluminum titanium carbide.

10. The process for preparing aluminum silicon alloy by fluoride salt method according to claim 9, characterized in that: The preparation method of cerium oxide modified aluminum titanium carbide comprises the following steps: subjecting a cerium source, a precipitant and aluminum titanium carbide to a hydrothermal reaction, and drying to obtain cerium oxide modified aluminum titanium carbide; The cerium source is a cerium salt solution with a mass concentration of 0.5% to 0.8%; The mass ratio of the cerium salt solution, the precipitant and the aluminum titanium carbide is 1-2:0.2:1.

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