Al-Mg intermediate alloy with high magnesium content and preparation method thereof

Abstract

The invention provides an Al-Mg intermediate alloy with high magnesium content and a preparation method of the Al-Mg intermediate alloy. In the Al-Mg intermediate alloy with high magnesium content, based on 100 wt.% of the Al-Mg intermediate alloy, the content of Mg is 45 wt.%-52 wt.%, the total content of RE and Ca is 0.1 wt.%-1.5 wt.%, the content of Fe is smaller than or equal to 0.15 wt.%, the content of Be is smaller than or equal to 0.002 wt.%, the content of Ca is smaller than or equal to 0.2 wt.%, the single content of other impurity elements is smaller than or equal to 0.1 wt.%, and the total content of the other impurity elements is smaller than or equal to 0.5 wt.%. The Al-Mg intermediate alloy with the high magnesium content is suitable for preparing Mg-containing aluminum alloy and has the advantages of being efficient, low in loss, stable in effect and environmentally friendly.

Description

Technical Field

[0001] The invention relates to the field of metal materials, and in particular to an Al-Mg master alloy with a high magnesium content and a preparation method thereof. Background Art

[0002] Mg is one of the commonly used alloying elements in aluminum alloys. It can improve the corrosion resistance of the alloy and form a second phase to strengthen the alloy. Therefore, it is widely added to different types of aluminum alloys, such as corrosion-resistant aluminum alloys (Al-Mg series), wrought aluminum (Al-Mg-Si-Cu series), hard aluminum (Al-Cu-Mg series), super hard aluminum (Al-Zn-Cu-Mg series), etc., where the Mg content ranges from 0.3wt.% to 10wt.%.

[0003] In industrial production, pure Mg is usually used as a raw material to add Mg to aluminum melt. However, Mg has a higher affinity for oxygen than Al, and is active and easily oxidized and burned. Therefore, during the addition process, Mg on the surface of the melt will first oxidize to form an MgO film. The loose MgO film will not only fail to protect the alloy, but will cause severe oxidation of the alloy, aggravating the loss of Mg, causing deviations in alloy composition and fluctuations in the composition of different batches of products. In addition, the oxide film will be drawn into the melt during the smelting process due to stirring operations and other reasons, resulting in oxide inclusion defects. These oxide inclusions often become hydrogen carriers, causing hydrogenation in the melt.

[0004] The above problems have brought great troubles to the production of magnesium-aluminum alloys, and the addition of Mg element has become a major problem in the alloy smelting process. Summary of the invention

[0005] The purpose of the present invention is to provide an Al-Mg master alloy with high magnesium content and low loss, stable effect, and environmental protection, which can be used in industry, and a preparation method thereof. The master alloy is suitable for preparing Mg-containing aluminum alloys including Al-Mg series alloys, and avoids a series of problems caused by using pure Mg to prepare alloys, such as alloy composition deviation caused by burning of Mg element, flue gas pollution, oxidation slag inclusion, etc., which saves energy and consumption, is environmentally friendly, saves time and labor, and improves product quality and reduces comprehensive costs.

[0006] According to one aspect of the present invention, there is provided an Al-Mg master alloy with a high magnesium content. Based on 100wt.% of the Al-Mg master alloy, the Mg content is 45wt.%-52wt.%, the total content of RE and Ca is 0.1wt.%-1.5wt.%, the Fe content is less than or equal to 0.15wt.%, the Be content is less than or equal to 0.002wt.%, the Ca content is less than or equal to 0.2wt.%, and the content of other impurity elements is less than or equal to 0.1wt.% individually, and the total amount is less than or equal to 0.5wt.%.

[0007] Optionally, RE includes at least one of La, Ce and Y.

[0008] According to another aspect of the present invention, a method for preparing an Al-Mg master alloy with a high magnesium content is provided, the method comprising: (1) adding an Al-RE alloy and an Al-Ca alloy to an aluminum melt to obtain a first melt; (2) continuously introducing Mg elements into the first melt so that the Mg content in the final melt is 45wt.%-52wt.%; (3) casting to obtain the Al-Mg master alloy with a high magnesium content, wherein in step (2), during the process of continuously introducing Mg elements, the melt temperature T is adjusted. 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃, where T 液相线 Refers to the liquidus temperature at the corresponding Mg content in the Al-Mg alloy phase diagram.

[0009] Optionally, in step (2), when the Mg content in the melt is less than or equal to 35 wt.%, as the Mg content increases, the melt temperature T is reduced. 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃, when the Mg content in the melt is greater than 35wt.%, as the Mg content increases, the melt temperature T 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃.

[0010] Optionally, the step (2) comprises: adjusting the temperature of the first melt to 695° C.-705° C., preheating pure Mg to 290° C.-310° C., and then adding the preheated pure Mg to the melt.

[0011] Optionally, when preheated pure Mg is added to the melt, the temperature of the melt is adjusted to decrease by 25°C-35°C for every 4wt.%-6wt.% increase in the magnesium content in the melt, until the magnesium content in the melt reaches 8wt.%-12wt.%, to obtain a second alloy melt, and the temperature of the second alloy melt is finally controlled within the range of 635°C-645°C.

[0012] Optionally, step (2) further comprises: transferring a portion of the second alloy melt and keeping it in another smelting furnace at a temperature of 620°C-630°C, continuing to add pure Mg preheated to 290°C-310°C to the remaining second alloy melt, and adjusting the temperature to decrease by 25°C-35°C for every 4wt.%-6wt.% increase in the magnesium content in the melt, until the magnesium content in the melt increases to 35wt.%.

[0013] Optionally, step (2) further comprises: after the magnesium content in the melt increases to 35wt.%, adding pure Mg preheated to 300°C and a second alloy melt having a holding temperature of 620°C-630°C alternately into the melt, and controlling the temperature of the alloy melt within the range of 470°C-510°C during the whole process.

[0014] According to another aspect of the present invention, a method for preparing an Mg-containing aluminum alloy is provided, wherein the Mg content in the Mg-containing aluminum alloy is 0.3wt.%-10wt.%, and the preparation method comprises: adding the Al-Mg intermediate alloy with a high magnesium content as described above to an aluminum melt at 680°C-760°C to prepare the Mg-containing aluminum alloy.

[0015] According to another aspect of the present invention, there is provided a Mg-containing aluminum alloy prepared by the preparation method as described above.

[0016] The Al-Mg master alloy with high magnesium content according to the present invention is suitable for preparing Mg-containing aluminum alloys including Al-Mg series alloys, and has the advantages of high efficiency and low loss, stable effect, and green environmental protection, and avoids a series of problems caused by using pure Mg to prepare alloys: such as Mg element burning leading to alloy composition deviation, flue gas pollution, oxidation slag inclusions, etc., which saves energy and consumption, is green and environmentally friendly, saves time and labor, and not only improves product quality, but also reduces comprehensive costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description in conjunction with the accompanying drawings.

[0018] Figure 1 The results of Al-0.5Mg alloy composition prepared by using pure magnesium and Al-50Mg master alloy according to the present invention are compared.

[0019] Figure 2 The results of Al-1Mg alloy composition prepared by using pure magnesium and Al-50Mg master alloy according to the present invention are compared.

[0020] Figure 3 The results of Al-5Mg alloy composition prepared by using pure magnesium and Al-50Mg master alloy according to the present invention are compared.

[0021] Figure 4 The results of Al-10Mg alloy composition prepared by using pure magnesium and Al-50Mg master alloy according to the present invention are compared.

[0022] Figure 5 The figure shows a field comparison of Al-5Mg alloy prepared using pure magnesium and Al-50Mg master alloy according to the present invention at 750°C. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in 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.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0025] Hereinafter, embodiments of the present disclosure will be described as follows with reference to the accompanying drawings.

[0026] However, the present disclosure may be exemplified in many different forms and should not be construed as limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0027] It should be understood that when the terms “include” and / or “comprises” are used in the specification, they list the presence of stated materials and / or components, but do not preclude the presence or addition of one or more other materials and / or components.

[0028] Al-Mg master alloy with high magnesium content

[0029] The present invention provides an Al-Mg master alloy with a high magnesium content. Based on 100wt.% of the Al-Mg master alloy, the Mg content is 45wt.%-52wt.%, the total content of RE and Ca is 0.1wt.%-1.5wt.%, the Fe content is less than or equal to 0.15wt.%, the Be content is less than or equal to 0.002wt.%, the Ca content is less than or equal to 0.2wt.%, and the contents of other impurity elements are individually less than or equal to 0.1wt.%, and the total amount is less than or equal to 0.5wt.%.

[0030] According to the present invention, RE and Ca are flame retardant elements with strong surface activity. They can form oxides during the smelting process, and together with the oxides of magnesium and aluminum, they form an intermediate layer of the surface film, which plays a flame retardant role and provides protection for the smelting process. By making the total content of RE and Ca in the Al-Mg master alloy with a high magnesium content 0.1wt.%-1.5wt.%, the flame retardant effect can be effectively achieved. If the total content of RE and Ca in the Al-Mg master alloy with a high magnesium content is less than 0.1wt.%, the flame retardant effect is insufficient; if the total content of RE and Ca in the Al-Mg master alloy with a high magnesium content is greater than 1.5wt.%, slag inclusion and other problems may occur.

[0031] According to an embodiment of the present invention, RE may include at least one of La, Ce and Y. According to an embodiment of the present invention, in the Al-Mg master alloy with a high magnesium content, the content of Ca is less than or equal to 0.2 wt.%.

[0032] According to an embodiment of the present invention, in the Al-Mg master alloy with a high magnesium content, the content of Fe is less than or equal to 0.15 wt.%. Fe can have a certain strengthening effect on the Al-Mg master alloy, but excessive Fe will easily generate slag inclusions.

[0033] According to an embodiment of the present invention, in the Al-Mg master alloy with a high magnesium content, the content of Be is less than or equal to 0.002 wt.%. Be can prevent the acidification of the Al-Mg alloy and improve the toughness, but excessive Be will lead to reduced corrosion resistance.

[0034] According to an embodiment of the present invention, in the Al-Mg master alloy with a high magnesium content, the content of other impurity elements is individually less than or equal to 0.1 wt.%, and the total amount is less than or equal to 0.5 wt.%.

[0035] According to the present invention, an Al-Mg master alloy with a high magnesium content is prepared, and the master alloy is suitable for preparing Mg-containing aluminum alloys including Al-Mg series alloys, thereby avoiding a series of problems caused by using pure Mg to prepare alloys, such as alloy composition deviation caused by burning of Mg elements, flue gas pollution, oxidized slag inclusions, etc., thereby saving energy and reducing consumption, being green and environmentally friendly, saving time and labor, and improving product quality while reducing overall costs.

[0036] Preparation method of Al-Mg master alloy with high magnesium content

[0037] The present invention provides a method for preparing an Al-Mg master alloy with a high magnesium content, the method comprising: (1) adding Al-RE alloy and Al-Ca alloy to an aluminum melt to obtain a first melt; (2) continuously introducing Mg element into the first melt, so that the Mg content in the final melt is 45wt.%-52wt.%; (3) casting to obtain the Al-Mg master alloy with a high magnesium content. In step (2), during the process of continuously introducing Mg element, the melt temperature T is adjusted. 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃, where T 液相线 Refers to the liquidus temperature at the corresponding Mg content in the Al-Mg alloy phase diagram.

[0038] According to an embodiment of the present invention, by continuously introducing the Mg element, the melt temperature T 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃, where T 液相线 Refers to the liquidus temperature at the corresponding Mg content in the Al-Mg alloy phase diagram.

[0039] According to an embodiment of the present invention, in step (1), RE and Ca are introduced. RE and Ca are flame retardant elements with strong surface activity. They can form oxides during the smelting process and form an intermediate layer of the surface film together with magnesium and aluminum oxides, which play a flame retardant role and provide protection for the smelting process.

[0040] In addition, according to an embodiment of the present invention, in step (2), during the process of continuously introducing the Mg element, the melt temperature T 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃, where T 液相线 Refers to the liquidus temperature at the corresponding Mg content in the Al-Mg alloy phase diagram. 熔体 Control to meet: T 液相线 <T 熔体 ≤T 液相线 +50℃ can further reduce the oxidation and combustion risks of the alloy melt.

[0041] According to the present invention, through the addition of the above two effects, the entire smelting process is free of covering agent, smoke and combustion, and the surface of the alloy after casting is bright and free of black oxide scale.

[0042] According to an embodiment of the present invention, in step (2), when the Mg content in the melt is less than or equal to 35 wt.%, as the Mg content increases, the melt temperature T is reduced. 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃; when the Mg content in the melt is greater than 35wt.%, as the Mg content increases, the melt temperature T 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃.

[0043] When the Mg content in the melt is less than or equal to 35wt.%, as the Mg content increases, the temperature of the liquidus of the Al-Mg alloy continues to decrease, so the melt temperature is continuously reduced to ensure that the melt temperature T 熔体 Meet T 液相线 <T 熔体 ≤T 液相线 +50℃. In addition, when the Mg content in the melt is greater than 35wt.%, as the Mg content increases, the temperature change of the liquidus line of the Al-Mg alloy is small, so the melt temperature T 熔体 To meet T 液相线 <T 熔体 ≤T 液相线 +50℃.

[0044] According to an embodiment of the present invention, step (2) may include: adjusting the temperature of the first melt to 695° C.-705° C., preheating pure Mg to 290° C.-310° C., and then adding the preheated pure Mg to the melt.

[0045] According to the present invention, the purpose of preheating pure magnesium is to accelerate its melting and dissolution rate in the alloy melt and reduce the risk of oxidation.

[0046] According to an embodiment of the present invention, when adding preheated pure Mg to the melt, the temperature of the melt is adjusted to decrease by 25°C-35°C for every 4wt.%-6wt.% increase in the magnesium content in the melt, until the magnesium content in the melt reaches 8wt.%-12wt.%, to obtain a second alloy melt, and the temperature of the second alloy melt is finally controlled within the range of 635°C-645°C. In the process of adding preheated pure Mg at a lower temperature to a melt at a higher temperature, if the melting furnace is not heated, the temperature of the melt will naturally decrease. The present invention ensures that the melt temperature T 熔体 Meet T 液相线 <T 熔体 ≤T 液相线+50℃. In addition, during the process of adding pure Mg continuously, the temperature in the melting furnace can be monitored in real time to meet the above conditions. For example, if the temperature drops too low without heating the melting furnace, the melting furnace can be heated appropriately. On the contrary, if the melt temperature is higher than 50℃ above the liquidus, the melting furnace is not heated.

[0047] According to an embodiment of the present invention, step (2) may further include: transferring a portion of the second alloy melt and keeping it in another smelting furnace at a temperature of 620°C-630°C, continuing to add pure Mg preheated to 290°C-310°C to the remaining second alloy melt, and adjusting the temperature to decrease by 25°C-35°C for every 4wt.%-6wt.% increase in the magnesium content in the melt, until the magnesium content in the melt increases to 35wt.%.

[0048] According to an embodiment of the present invention, step (2) may further include: after the magnesium content in the melt increases to 35wt.%, pure Mg preheated to 300°C and a second alloy melt with a holding temperature of 620°C-630°C are alternately added to the melt, and the temperature of the alloy melt is controlled within the range of 470°C-510°C during the whole process.

[0049] That is, after obtaining the second alloy melt with a magnesium content of 8wt.%-12wt.%, the second alloy melt is divided into two parts, one part is kept warm, and the other part continues to add pure Mg preheated to 290°C-310°C until the magnesium content in the melt increases to 35wt.%, which is conducive to lowering the temperature of the melt by natural cooling (i.e., only by adding preheated pure Mg without opening the melting furnace). 熔体 Satisfaction: T 液相线 <T 熔体 ≤T 液相线 +50° C. The present invention does not impose any specific restrictions on the ratio of the two parts of the second alloy melt. For example, the ratio of the heat-insulated second alloy melt to the other part of the second alloy melt may be 3:1 to 1:3.

[0050] In addition, according to an embodiment of the present invention, pure magnesium preheated to 300°C and Al-10Mg melt at about 620°C-630°C are alternately added to prevent the alloy melt from cooling too severely and solidifying if only pure magnesium is added. Therefore, by alternately adding pure magnesium preheated to 300°C and Al-10Mg melt at about 620°C-630°C, the melt temperature T can be controlled without adjusting the melting furnace. 熔体 Satisfaction: T 液相线 <T 熔体 ≤T 液相线 +50℃.

[0051] The method for preparing the Al-Mg master alloy with a high magnesium content according to the present invention can reduce the oxidation and combustion risks of the alloy melt.

[0052] Preparation method of Mg-containing aluminum alloy and Mg-containing aluminum alloy

[0053] According to an embodiment of the present invention, a method for preparing an Mg-containing aluminum alloy can also be provided, wherein the Mg content in the Mg-containing aluminum alloy is 0.3wt.%-10wt.%, and the preparation method comprises: adding the Al-Mg intermediate alloy with a high magnesium content as described above to an aluminum melt at 680°C-760°C to prepare the Mg-containing aluminum alloy.

[0054] First, pure aluminum can be melted and then heated to 680°C-760°C, at which temperature, the Al-Mg master alloy with a high magnesium content according to the present invention is added to prepare a Mg-containing aluminum alloy. As an example, the Mg-containing aluminum alloy can be an Al-Mg alloy represented by Al-xMg, where x is 0.3wt.%-10wt.%. However, the present invention is not limited to this. According to an embodiment of the present invention, the Mg-containing aluminum alloy may also include Al-Mg-Si alloys (for example, Al-Mg-Si-Cu alloys), Al-Si-Mg alloys, Al-Cu-Mg alloys, Al-Zn-Mg alloys, and Al-Zn-Cu-Mg alloys.

[0055] Hereinafter, a specific example of a method for producing an Al-Mg master alloy having a high magnesium content and a specific example of an aluminum alloy containing Mg will be described.

[0056] Example

[0057] Preparation of Al-Mg Master Alloy with High Magnesium Content

[0058] According to Al-50Mg master alloy, in which the La content is 0.6wt.%, the Ca content is 0.1wt.%, and the Fe content is 0.1wt.%, prepare the required raw materials: pure aluminum, pure magnesium, Al-La alloy, and Al-Ca alloy.

[0059] Add pure aluminum to the melting furnace, heat it up to 720°C and melt it. Add Al-RE alloy and Al-Ca alloy to the aluminum melt and stir until dissolved. Adjust the temperature of the alloy melt to 700°C, preheat pure magnesium to 300°C and add it to the alloy melt. For every 5wt.% increase in the magnesium content in the alloy melt, adjust the temperature to 30°C until the magnesium content in the alloy melt reaches 10%. The melt temperature is finally controlled at 640°C.

[0060] Half of the Al-10Mg alloy melt was transferred out and kept in another melting furnace at 620° C. Pure magnesium preheated to 300° C. was added to the remaining Al-10Mg alloy melt, and the temperature was adjusted to decrease by 30° C. for every 5 wt.% increase in the magnesium content in the alloy melt, until the magnesium content in the alloy melt increased to 35 wt.%.

[0061] Then, pure magnesium preheated to 300°C and Al-10Mg melt at about 620°C are alternately added to the above alloy melt, and the temperature of the alloy melt is controlled within the range of 470°C-510°C during the whole process. The above alloy melt is sampled and tested, and after the composition is qualified, Al-50Mg master alloy is cast.

[0062] Preparation of Mg-containing aluminum alloy

[0063] Example

[0064] In a smelting furnace, Al-Mg alloy was prepared using pure aluminum and the Al-50Mg-0.6La-0.1Ca-0.1Fe master alloy prepared as above.

[0065] First, pure aluminum was melted, and Al-50Mg master alloy was added to the aluminum melt at an addition temperature of 700°C to prepare Al-0.5Mg alloy. Al-1Mg alloy, Al-5Mg alloy and Al-10Mg alloy were prepared using the same method, and 6 heats of alloys were prepared for each component.

[0066] In addition, Al-50Mg master alloy was added to the aluminum melt at an addition temperature of 750°C to prepare Al-1Mg and Al-5Mg alloys, and 6 heats of alloys were prepared for each composition.

[0067] Comparative Example

[0068] In a melting furnace, pure aluminum and pure magnesium are used to prepare Al-Mg alloy.

[0069] First, pure aluminum was melted at an addition temperature of 700°C, and then pure magnesium was added to the aluminum melt to prepare Al-0.5Mg alloy. Using the same method, Al-1Mg alloy, Al-5Mg alloy and Al-10Mg alloy were prepared, and 6 heats of alloys were prepared for each composition.

[0070] In addition, Al-1Mg and Al-5Mg alloys were prepared by adding pure magnesium to the aluminum melt at an addition temperature of 750°C, and 6 heats of alloys were prepared for each composition.

[0071] Composition measurement

[0072] The Mg content in the Al-Mg alloys of the embodiments and comparative examples was measured by energy dispersive spectrometer (EDS), the Mg content of 6 heats of each component alloy at each addition temperature was averaged, and the standard deviation was calculated based on the average value.

[0073] Figure 1 The Mg content in six heats of Al-0.5Mg alloys prepared at an addition temperature of 700°C using pure magnesium and pure aluminum as well as the Al-50Mg master alloy of the present invention and pure aluminum is shown.

[0074] Figure 2 The Mg content in 6 heats of Al-1Mg alloys prepared using pure magnesium and pure aluminum as well as the Al-50Mg master alloy of the present invention and pure aluminum at addition temperatures of 700°C and 750°C is shown.

[0075] Figure 3 The Mg content in six heats of Al-5Mg alloys prepared using pure magnesium and pure aluminum as well as the Al-50Mg master alloy of the present invention and pure aluminum at addition temperatures of 700°C and 750°C is shown.

[0076] Figure 4 The Mg content in six heats of Al-10Mg alloys prepared at an addition temperature of 700°C using pure magnesium and pure aluminum as well as the Al-50Mg master alloy of the present invention and pure aluminum is shown.

[0077] Figure 5 The figure shows a field comparison of Al-5Mg alloy prepared using pure magnesium and Al-50Mg master alloy according to the present invention at 750°C.

[0078] Table 1 shows the mean and standard deviation of the Mg content of six heats of each alloy composition at each preparation temperature.

[0079] Table 1

[0080]

[0081] from Figures 1 to 5As well as the composition results and application field comparison of Al-xMg alloys (x is 0.5, 1, 5 and 10) prepared using pure magnesium and the Al-50Mg master alloy of the present invention in Table 1, it can be learned that: 1) the Mg content of the Al-xMg alloy prepared using the Al-50Mg master alloy of the embodiment of the present invention is generally higher than that of the Al-xMg alloy prepared using pure magnesium; 2) the standard deviation of the Mg content of multiple batches of Al-xMg alloys prepared using the Al-50Mg master alloy of the embodiment of the present invention is much smaller than that of the Al-xMg alloy prepared using pure magnesium. , indicating that the effect of Al-50Mg master alloy is more stable; 3) The Al-50Mg master alloy of the embodiment of the present invention is not sensitive to the change of melting temperature. The Mg content of the Al-1Mg alloy prepared under low temperature (700°C) and high temperature (750°C) conditions is basically the same, and the Mg content of the Al-5Mg alloy prepared under low temperature (700°C) and high temperature (750°C) conditions is basically the same. For the Al-1Mg alloy and Al-5Mg alloy prepared with pure magnesium, the burning loss is obviously serious after the melting temperature (750°C) is increased (such as Figure 5 shown).

[0082] The Al-Mg master alloy with a high magnesium content according to the embodiment of the present invention can achieve beneficial technical effects not limited to the following description.

[0083] 1. Stable effect: The use of Al-Mg master alloys with high magnesium content to prepare Al-Mg series or other Mg-containing aluminum alloys can ensure that the Mg content of products from different batches is basically consistent.

[0084] 2. Energy saving and consumption reduction, wide adaptability: When the alloy is added at a relatively low temperature (680-700℃), it can be quickly dissolved in the aluminum melt and has a high absorption rate; when added at a relatively high temperature (740-760℃), it can avoid burning, basically maintain the absorption rate when added at a low temperature, and avoid the introduction of oxide slag.

[0085] 3. Green and environmentally friendly: The application of this alloy can avoid the flue gas emission pollution caused by the burning of alloy elements.

[0086] 4. Save time and labor: The alloy is easy to break and does not require the use of processing machine tools or other equipment to cut and prepare the material.

[0087] While exemplary embodiments of the present invention have been described in detail with reference to examples, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the claims.

Claims

1. An Al-Mg master alloy with a high magnesium content, characterized in that: Based on 100wt.% of the Al-Mg master alloy, the Mg content is 45wt.%-52wt.%, the total content of RE and Ca is 0.1wt.%-1.5wt.%, the Fe content is less than or equal to 0.15wt.%, the Be content is less than or equal to 0.002wt.%, the Ca content is less than or equal to 0.2wt.%, and the content of other impurity elements is less than or equal to 0.1wt.% individually, and the total amount is less than or equal to 0.5wt.%.

2. The Al-Mg master alloy with high magnesium content according to claim 1, characterized in that: RE includes at least one of La, Ce, and Y.

3. A method for preparing an Al-Mg master alloy with a high magnesium content according to claim 1 or 2, characterized in that: The preparation method comprises: (1) adding Al-RE alloy and Al-Ca alloy to aluminum melt to obtain a first melt; (2) continuously introducing Mg element into the first melt so that the Mg content in the final melt is 45 wt.%-52 wt.%; (3) casting to obtain the Al-Mg master alloy with high magnesium content, In step (2), while continuously introducing the Mg element, the melt temperature T is adjusted. 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃, Among them, T 液相线 Refers to the liquidus temperature at the corresponding Mg content in the Al-Mg alloy phase diagram.

4. The preparation method according to claim 3, characterized in that: In the step (2), when the Mg content in the melt is less than or equal to 35 wt.%, as the Mg content increases, the melt temperature T is reduced. 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃, When the Mg content in the melt is greater than 35wt.%, as the Mg content increases, the melt temperature T 熔体 To meet: T 液相线 <T 熔体 ≤T 液相线 +50℃.

5. The preparation method according to claim 4, characterized in that: The step (2) comprises: The temperature of the first melt is adjusted to 695° C.-705° C., pure Mg is preheated to 290° C.-310° C., and then the preheated pure Mg is added into the melt.

6. The preparation method according to claim 4, characterized in that: When preheated pure Mg is added to the melt, the temperature of the melt is adjusted to decrease by 25°C-35°C for every 4wt.%-6wt.% increase in the magnesium content in the melt, until the magnesium content in the melt reaches 8wt.%-12wt.%, to obtain a second alloy melt, and the temperature of the second alloy melt is finally controlled within the range of 635°C-645°C.

7. The preparation method according to claim 6, characterized in that: The step (2) further comprises: transferring a portion of the second alloy melt and keeping it in another smelting furnace at a temperature of 620°C-630°C, continuing to add pure Mg preheated to 290°C-310°C to the remaining second alloy melt, and adjusting the temperature to decrease by 25°C-35°C for every 4wt.%-6wt.% increase in the magnesium content in the melt, until the magnesium content in the melt increases to 35wt.%.

8. The preparation method according to claim 7, characterized in that: The step (2) further comprises: After the magnesium content in the melt increases to 35wt.%, pure Mg preheated to 300°C and a second alloy melt with a holding temperature of 620°C-630°C are alternately added to the melt. The temperature of the alloy melt is controlled within the range of 470°C-510°C during the whole process.

9. A method for preparing a Mg-containing aluminum alloy, wherein the Mg content of the Mg-containing aluminum alloy is 0.3wt.%-10wt.%, characterized in that: The preparation method comprises: The Al-Mg master alloy with a high magnesium content according to claim 1 or 2 is added to an aluminum melt at 680° C.-760° C. to prepare the Mg-containing aluminum alloy.

10. A Mg-containing aluminum alloy prepared according to the preparation method according to claim 9.

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