Manganese element additive for aluminum alloy production and preparation method thereof

Abstract

The invention provides a manganese additive for aluminum alloy production and a preparation method thereof, and belongs to the technical field of manganese additives. The preparation method provided by the invention comprises the following steps: mixing aluminum fluoride and potassium fluoride, dissolving, and pouring to obtain lump villiaumite; crushing the lump villiaumite into villiaumite powder; and finally, fully mixing the villiaumite powder and the electrolytic manganese powder, and briquetting to obtain the blocky manganese additive. And the obtained manganese element additive can be rapidly dissolved, oxidizing slag is not prone to being generated, and oxide in molten aluminum can be removed easily.

Description

Technical Field

[0001] The invention belongs to the technical field of manganese additives, and specifically relates to a manganese element additive for aluminum alloy production and a preparation method thereof. Background Art

[0002] In aluminum alloys, manganese will form strengthening particles such as MnAl6 with aluminum, thereby playing a role in solid solution strengthening. However, since the melting point of Mn is as high as 1244℃, and the temperature of aluminum liquid is generally controlled at 700~740℃, it is a difficult problem to find a method to add manganese to aluminum. At present, the main addition method is to use aluminum-manganese master alloy or manganese element additives, among which the manganese element additives are mainly composed of metal powder, flux and binder, and the flux is generally sodium salt or chloride salt. Although this type of additive solves the problem of adding in the form of aluminum-based master alloy, due to moisture absorption and strong odor, it not only brings slag pollution to the aluminum liquid, but also affects the environment and human health. In addition, there is also the disadvantage of low actual yield. Other additives, such as the Chinese invention patent with application number 202311196570.8, discloses a method for preparing manganese element additives for the production of aluminum alloys. The manganese element additives include manganese powder, a solvent and a binder. The solvent is selected from one or more of aluminum powder or fluoroaluminates, and the fluoroaluminates are potassium fluoroaluminate and / or sodium fluoroaluminate; the binder is selected from one or more of magnesium stearate or sodium stearate. Although this type of additive does not use sodium salt or chloride salt solvents, it still requires the use of a binder. The use of a binder will cause other impurities to enter and produce slag. In response to these problems, both domestic and foreign countries are committed to developing a new production technology for manganese element additives. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a manganese element additive for aluminum alloy production which can be quickly dissolved and is not easy to produce oxide slag, and a preparation method thereof.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for preparing a manganese element additive for aluminum alloy production, comprising the following steps: S1, mixing aluminum fluoride and potassium fluoride, dissolving them, and pouring them to obtain a block of fluoride salt; S2, crushing the block fluoride salt into fluoride salt powder; S3, fully mixing the fluoride salt powder and the electrolytic manganese powder and pressing them into blocks to obtain a block-shaped manganese element additive.

[0005] A manganese element additive for aluminum alloy production is prepared by the above-mentioned preparation method.

[0006] The beneficial effect of the present invention is that: the present invention generates a mixture of K3AlF6 and KAlF4 by aluminum fluoride (AlF3) and potassium fluoride (KF). The mixture of K3AlF6 and KAlF4 has a low melting point and strong slag removal performance, and can be used in the production of aluminum alloy without adding a binder. When it is used to produce aluminum alloy, it can be quickly dissolved after being added to aluminum liquid, and the manganese agent sinks in the aluminum liquid and expands as the temperature rises until it breaks. In the whole process, the mixed fluoride salt is not only a co-solvent, but also can remove oxides in the aluminum liquid after breaking. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 This is a graph showing the absorption rate of the manganese element additive used in the production of aluminum alloy according to an embodiment of the present invention. DETAILED DESCRIPTION

[0008] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0009] A method for preparing a manganese element additive for aluminum alloy production comprises the following steps: S1, mixing aluminum fluoride and potassium fluoride, dissolving them, and pouring them to obtain a block of fluoride salt; S2, crushing the block fluoride salt into fluoride salt powder; S3, fully mixing the fluoride salt powder and the electrolytic manganese powder and pressing them into blocks to obtain a block-shaped manganese element additive.

[0010] From the above description, it can be seen that the beneficial effect of the present invention is that: the preparation method provided by the present invention first uses AlF3 and KF to prepare a block fluoride salt of a mixture of K3AlF6 and KAlF4, and then crushes it into a fluoride salt powder with good fluidity and then mixes it with manganese powder, and presses it to obtain a block manganese element additive. On the one hand, this preparation method can prepare a manganese additive with a low melting point (about 560°C) and fast dissolution. At the same time, through strict control of the process, it can achieve the control of the quality of the block manganese element additive, so that the block weight deviation is ±5g, and the block density is 4.2~5.2g / cm 3 .

[0011] Furthermore, the mass ratio of aluminum fluoride to potassium fluoride in S1 is 52-56:48-44, preferably 54:46.

[0012] Furthermore, the dissolution temperature in S1 is 650-850°C, preferably 750-850°C.

[0013] Furthermore, the particle size of the fluoride salt powder meets the following requirements: less than 20 mesh ≤ 1%, 20-60 mesh ≥ 50%, 60-100 mesh ≥ 20%, greater than 100 mesh ≤ 10%. The block fluoride salt can be crushed into powder with particles less than 20 mesh by a jaw crusher and a double rotor crusher so that its particle size meets the above requirements. When the particle size meets this range, the fluidity of the fluoride salt powder reaches 0.5g / s.

[0014] Furthermore, the particle size of the electrolytic manganese powder meets the following requirements: less than 30 mesh ≤5%, 30-40 mesh ≤20%, 40-300 mesh ≥70%, greater than 300 mesh ≤5%. When the particle size meets this range, the fluidity of the electrolytic manganese powder reaches 1.0 g / s.

[0015] From the above description, it can be seen that by controlling the particle size of fluoride salt powder and manganese powder, its fluidity can be controlled, and then the weight of the briquette can be controlled within ±5g and the density can be controlled within 4.2~5.2g / cm 3 , ensuring the uniformity of product quality.

[0016] Furthermore, the manganese content in the electrolytic manganese powder is 99.5-99.9%.

[0017] Furthermore, the density of the briquette is 4.2~5.2g / cm 3 .

[0018] Furthermore, the block-shaped manganese element additive is packaged in aluminum foil.

[0019] A manganese element additive for aluminum alloy production is prepared by any preparation method.

[0020] Embodiment 1 of the present invention is: A method for preparing a manganese element additive for aluminum alloy production comprises the following steps: S1. Put 54 kg of aluminum fluoride and 46 kg of potassium fluoride into a graphite crucible medium frequency furnace, heat it to 800°C to dissolve, then cool it to 600°C, cast it into blocks, and obtain block fluoride salt; S2. The block fluoride salt obtained in S1 is crushed into powder with particle size below 20 mesh by a jaw crusher and a double-rotor crusher to obtain fluoride salt powder; the particle size of the fluoride salt powder satisfies the following requirements: less than 20 mesh ≤ 1%, 20-60 mesh ≥ 50%, 60-100 mesh ≥ 20%, greater than 100 mesh ≤ 10%; S3, fully mixing 20% ​​of the fluoride salt powder obtained in S2 with 80% of the electrolytic manganese powder, and pressing them into blocks by a 125t automatic horizontal hydraulic press to obtain a block-shaped manganese element additive; The manganese content in electrolytic manganese powder is 99.7%, and the particle size meets the following requirements: less than 30 mesh ≤5%, 30-40 mesh ≤20%, 40-300 mesh ≥70%, greater than 300 mesh ≤5%; The blocky manganese element additive obtained in S4 and S3 is packed with aluminum foil and then packed into a carton.

[0021] The absorption rate curve of the block manganese element additive obtained in Example 1 is shown in Figure 1 shown.

[0022] Comparative Example 1: A method for preparing a manganese element additive for aluminum alloy production comprises the following steps: S1. Aluminum fluoride, potassium fluoride and electrolytic manganese powder of the same proportion and source (manufacturer model) as in Example 1 are mixed by a V-type mixer, and then pressed into blocks by a 125t automatic horizontal hydraulic press to obtain a block-shaped manganese element additive.

[0023] The blocky manganese element additives obtained in Example 1 and Comparative Example 1 were tested, and the results are shown in Table 1.

[0024] Table 1

[0025] Embodiment 2 of the present invention is: A method for preparing a manganese element additive for aluminum alloy production comprises the following steps: S1. Put 52 kg of aluminum fluoride and 48 kg of potassium fluoride into a graphite crucible medium frequency furnace, heat it to 750°C to dissolve, then cool it to 600°C, cast it into blocks, and obtain block fluoride salt; S2. The block fluoride salt obtained in S1 is crushed into powder with particle size below 20 mesh by a jaw crusher and a double-rotor crusher to obtain fluoride salt powder; the particle size of the fluoride salt powder satisfies the following requirements: less than 20 mesh ≤ 1%, 20-60 mesh ≥ 50%, 60-100 mesh ≥ 20%, greater than 100 mesh ≤ 10%; S3, fully mixing 15% of the fluoride salt powder obtained in S2 with 85% of the electrolytic manganese powder, and pressing them into blocks by a 125t automatic horizontal hydraulic press to obtain a block-shaped manganese element additive; The manganese content in electrolytic manganese powder is 99.5%, and the particle size meets the following requirements: less than 30 mesh ≤5%, 30-40 mesh ≤20%, 40-300 mesh ≥70%, greater than 300 mesh ≤5%; The blocky manganese element additive obtained in S4 and S3 is packed with aluminum foil and then packed into a carton.

[0026] Embodiment 3 of the present invention is: A method for preparing a manganese element additive for aluminum alloy production comprises the following steps: S1. Put 56 kg of aluminum fluoride and 44 kg of potassium fluoride into a graphite crucible medium frequency furnace, heat it to 850°C to dissolve, then cool it to 600°C, cast it into blocks, and obtain block fluoride salt; S2. The block fluoride salt obtained in S1 is crushed into powder with particle size below 20 mesh by a jaw crusher and a double-rotor crusher to obtain fluoride salt powder; the particle size of the fluoride salt powder satisfies the following requirements: less than 20 mesh ≤ 1%, 20-60 mesh ≥ 50%, 60-100 mesh ≥ 20%, greater than 100 mesh ≤ 10%; S3, fully mixing 25% of the fluoride salt powder obtained in S2 with 75% of the electrolytic manganese powder, and pressing them into blocks by a 125t automatic horizontal hydraulic press to obtain a block-shaped manganese element additive; The manganese content in electrolytic manganese powder is 99.9%, and the particle size meets the following requirements: less than 30 mesh ≤5%, 30-40 mesh ≤20%, 40-300 mesh ≥70%, greater than 300 mesh ≤5%; The blocky manganese element additive obtained in S4 and S3 is packed with aluminum foil and then packed into a carton.

[0027] In summary, the preparation method of the manganese element additive for aluminum alloy production provided by the present invention does not require the addition of a binder during the preparation process, does not introduce new impurities, and is easy to produce. The obtained manganese element additive can be quickly dissolved after being added to the aluminum liquid, and can effectively remove oxides in the aluminum liquid while adding manganese, thereby avoiding the generation of scum and other problems.

[0028] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing a manganese element additive for aluminum alloy production, characterized in that: The following steps are involved: S1, mixing aluminum fluoride and potassium fluoride, dissolving them, and pouring them to obtain a block of fluoride salt; S2, crushing the block fluoride salt into fluoride salt powder; S3, fully mixing the fluoride salt powder and the electrolytic manganese powder and pressing them into blocks to obtain a block-shaped manganese element additive.

2. The method for preparing a manganese element additive for aluminum alloy production according to claim 1, characterized in that: The mass ratio of aluminum fluoride to potassium fluoride in S1 is 52-56:48-44.

3. The method for preparing the manganese element additive for aluminum alloy production according to claim 1, characterized in that: The dissolution temperature in S1 is 650~850℃.

4. The method for preparing a manganese element additive for aluminum alloy production according to claim 1, characterized in that: The particle size of the fluoride salt powder meets the following requirements: less than 20 mesh ≤ 1%, 20-60 mesh ≥ 50%, 60-100 mesh ≥ 20%, greater than 100 mesh ≤ 10%.

5. The method for preparing the manganese element additive for aluminum alloy production according to claim 1, characterized in that: The particle size of the electrolytic manganese powder meets the following requirements: less than 30 mesh ≤5%, 30-40 mesh ≤20%, 40-300 mesh ≥70%, and greater than 300 mesh ≤5%.

6. The method for preparing a manganese element additive for aluminum alloy production according to claim 1, characterized in that: The manganese content in the electrolytic manganese powder is 99.5-99.9%.

7. The method for preparing a manganese element additive for aluminum alloy production according to claim 1, characterized in that: The density of the briquette is 4.2-5.2 g / cm 3 .

8. The method for preparing a manganese element additive for aluminum alloy production according to claim 1, characterized in that: The blocky manganese element additive is packaged in aluminum foil.

9. A manganese element additive for aluminum alloy production, characterized in that: The method is prepared according to any one of claims 1 to 8.

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