CN116752016A - Aluminum alloy for casting and preparation method thereof - Google Patents

Abstract

An aluminum alloy for casting, the alloy consists of the following mass percentage components: manganese: 1.0%-1.8%; iron 0.3%-0.5%; rare earth elements 0.1-0.3%; the balance is aluminum and trace impurities, of which trace amounts The total mass percentage of impurities is less than 0.6%. The preparation method includes the following steps: S1: Calculate and weigh pure manganese, pure iron, pure aluminum, and aluminum rare earth alloy as raw materials according to the mass percentage of the raw materials; S2: Put the flux in the crucible, and then add the preheated pure aluminum block; when the crucible pot temperature rises to 1260~1300℃, add the preheated pure manganese block; when the crucible pot temperature rises to 1600~1650℃, add the preheated pure iron block; after all the above raw materials are melted, lower the crucible pot temperature to 730 ~740°C, add the preheated aluminum rare earth alloy, stir evenly for refining, degassing and keep warm for more than one hour to obtain alloy liquid; S3: When the crucible pot temperature drops to 690~700°C, pour the alloy liquid into the casting The ingot is obtained from the mold cavity.

Description

Aluminum alloy for casting and preparation method thereof

Technical field

The invention relates to an aluminum alloy for casting and a preparation method thereof.

Background technique

Aluminum alloy, as a traditional metal material, is widely used in various industries, such as 3003 aluminum alloy, etc. However, various existing aluminum alloy materials put forward higher requirements for the performance of aluminum alloys when used for casting. The aluminum alloys in the existing technology still have the possibility of greater improvement when they are suitable for casting. sex.

Contents of the invention

In order to overcome the shortcomings of existing aluminum alloys used in casting, the present invention provides an aluminum alloy for casting and a preparation method thereof, so that the aluminum alloy is better suitable for casting.

The technical solution of the present invention to solve the technical problem is: an aluminum alloy for casting, which is composed of the following components in mass percentage:

Manganese: 1.0%-1.8%. Manganese can prevent the recrystallization process of aluminum alloys, increase the recrystallization temperature, and significantly refine the recrystallized grains. The refinement of recrystallized grains is mainly caused by the dispersed particles of MnAl ₆ compound hindering the growth of recrystallized grains. Another function of MnAl ₆ is to dissolve impurity iron to form (Fe, Mn)Al ₆ and reduce the harmful effects of iron. At the same time, Mn can significantly increase the corrosion resistance of aluminum alloys and increase the casting performance of aluminum alloys.

Iron 0.3%-0.5%. Under normal circumstances, iron is an impurity element in aluminum alloys and has a significant impact on the properties of the alloy. However, in the present invention, the trace addition of iron can make the aluminum alloy easier to cast. Demolding, thereby greatly reducing the mold sticking phenomenon. At the same time, as mentioned above, due to the addition of Mn, the harmful effects of iron can be reduced.

Rare earth elements 0.1-0.3%. The functions of adding rare earth elements are: 1. Refining and purification: Rare earth elements have a good purification effect on aluminum alloy melt. First of all, rare earths easily form chemically stable compounds such as RE2O3, RE2S3, RES, RES2, RE3S4, REH2, REH3, REX3 (X is a halogen element) with O, S, halogen elements, etc., and react with N acts to generate refractory REN. At high temperatures, rare earths react with C, Si, and B to form REC2, RE2C3, REC, RE2C, RE3C, RE4C, RESi2, REB4, REB6, etc. At the same time, rare earths have a particularly strong adsorption force for hydrogen and can adsorb and dissolve hydrogen in large amounts, which can effectively remove hydrogen from aluminum alloys. The compounds of rare earths and hydrogen have a higher melting point and are dispersed in the aluminum liquid. This part is formed by compounds. The hydrogen will not form bubbles, greatly reducing the hydrogen content and pinhole rate of aluminum. Secondly, rare earths can combine with low-melting-point elements Sn, Bi, Pb, Zn, etc. in aluminum alloys to form binary or multi-component compounds with high melting points and light density. When the metal smelting temperature is lower than their melting points, these compounds float to form slag and precipitate. Thus, the aluminum liquid is purified, and their tiny particles become heterogeneous crystal nuclei in the aluminum crystallization process, thereby refining the grains. Finally, adding rare earths can improve the surface tension, fluidity, viscosity and other physical and chemical properties of aluminum alloy melt and slag, which is beneficial to the spheroidization of non-metallic inclusions and promotes their floating, thus effectively removing non-metallic inclusions;

2. Refinement and metamorphism: After adding rare earth elements, the α (Al) phase grains begin to become smaller, which plays a certain role in refining the grains. The originally thick and dendritic α (Al) phase changes into a smaller rose shape. Or rod-shaped, when the rare earth content is 0.3%, the α (Al) phase has the smallest grains, and as the rare earth content further increases, the grains gradually become larger. In addition, the compound formed by aluminum and rare earths greatly increases the number of crystal nuclei during metal crystallization, which also refines the alloy structure;

3. Alloying: There are three main forms of rare earth elements in aluminum alloys: solid solution in the matrix α (Al); segregation in phase boundaries, grain boundaries and dendrite boundaries; solid solution in compounds or as compounds Form exists. Its existence form has a great relationship with the addition amount. When the rare earth content is low, the rare earth is mainly distributed in the first two forms. Through limited solid solution and increased deformation resistance, it promotes the proliferation of dislocations to achieve strengthening; when the rare earth content is large, Mainly in the third form of existence, rare earths and other elements in the alloy form many new phases containing rare earths, which are distributed within the grains or grain boundaries, and at the same time change the shape and size of the second phase (most of them contain rare earths) The second phase has the characteristics of particleization, spheroidization and refinement), and a large number of dislocations appear, which strengthens the aluminum alloy to a certain extent.

The balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

It should be noted that the proportions in the alloy of the present invention are obtained by combining theory with long-term experiments. Even if the mass percentage is changed slightly, great differences will occur.

Preferably, the alloy is composed of the following mass percentage components: manganese: 1.5%; iron 0.4%; rare earth elements 0.3%; the balance is aluminum and trace impurities.

Preferably, the rare earth element is one or both of La and Ce.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: According to the mass percentage of raw materials, calculate and weigh pure manganese, pure iron, pure aluminum, and aluminum rare earth alloy as raw materials, that is, the rare earth elements are added in the form of aluminum rare earth alloy.

S2: Put the flux in the crucible, and then add the preheated pure aluminum block; when the crucible pot temperature rises to 1260~1300℃, add the preheated pure manganese block; when the crucible pot temperature rises to 1600~1650℃, add the preheated pure manganese block Pure iron block; after all the above raw materials are melted, lower the crucible pot temperature to 730-740°C, add the preheated aluminum rare earth alloy, stir evenly, perform refining, degassing and keep warm for more than one hour to obtain an alloy liquid. Since there is a certain incubation period for the rare earth metamorphism, the rare earth will exert its maximum metamorphic effect only if it is maintained at high temperature for a certain period of time. Therefore, it must be guaranteed for more than one hour after adding the preheated aluminum rare earth alloy in this step.

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Preferably, in step S2, the pure aluminum block is preheated to 200-250°C; the pure manganese block is preheated to 400-450°C; the pure iron block is preheated to 500-550°C; and the aluminum rare earth alloy is preheated to 150-200°C. ℃.

The beneficial effect of the present invention is that the present invention provides an aluminum alloy with specific components, so that the aluminum alloy is more suitable for casting.

Implementation

The present invention will be described in further detail below with reference to examples.

Embodiment 1, an aluminum alloy for casting, characterized in that the alloy is composed of the following mass percentage components:

Mn: 1.5%; Fe: 0.4%; La: 0.3%; the balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, and Al-La alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-La alloy that has been preheated to 150-200℃ , and stir evenly for refining, degassing and keeping warm for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Embodiment 2, an aluminum alloy for casting, characterized in that the alloy consists of the following mass percentage components:

Mn: 1.0%; Fe: 0.45%; Ce: 0.2%; the balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, and Al-Ce alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-Ce alloy that has been preheated to 150-200℃ , and stir evenly for refining, degassing and keeping warm for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Embodiment 3, an aluminum alloy for casting, characterized in that the alloy is composed of the following mass percentage components:

Mn: 1.8%; Fe: 003%; La: 0.11%; the balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, and Al-La alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-La alloy that has been preheated to 150-200℃ , and stir evenly for refining, degassing and keeping warm for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Embodiment 4, an aluminum alloy for casting, characterized in that the alloy is composed of the following mass percentage components:

Mn: 1.1%; Fe: 0.5%; Ce: 0.25%; the balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, and Al-Ce alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-Ce alloy that has been preheated to 150-200℃ , and stir evenly for refining, degassing and keeping warm for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Embodiment 5, an aluminum alloy for casting, characterized in that the alloy is composed of the following mass percentage components:

Mn: 1.2%; Fe: 0.32%; Ce: 0.1%; La: 0.03%. The balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, Al-Ce alloy, and Al-La alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-Ce alloy that has been preheated to 150-200℃ , Al-La alloy, and stir evenly for refining, degassing and heat preservation for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Embodiment 6, an aluminum alloy for casting, characterized in that the alloy consists of the following mass percentage components:

Mn: 1.7%; Fe: 0.43%; Ce: 0.05%; La: 0.05%. The balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, Al-Ce alloy, and Al-La alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-Ce alloy that has been preheated to 150-200℃ , Al-La alloy, and stir evenly for refining, degassing and heat preservation for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Embodiment 7, an aluminum alloy for casting, characterized in that the alloy consists of the following mass percentage components:

Mn: 1.6%; Fe: 0.48%; Ce: 0.05%; La: 0.1%. The balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, Al-Ce alloy, and Al-La alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-Ce alloy that has been preheated to 150-200℃ , Al-La alloy, and stir evenly for refining, degassing and heat preservation for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Embodiment 8, an aluminum alloy for casting, characterized in that the alloy is composed of the following mass percentage components:

Mn: 1.3%; Fe: 0.35%; Ce: 0.15%; La: 0.13%. The balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, Al-Ce alloy, and Al-La alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-Ce alloy that has been preheated to 150-200℃ , Al-La alloy, and stir evenly for refining, degassing and heat preservation for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Embodiment 9, an aluminum alloy for casting, characterized in that the alloy is composed of the following mass percentage components:

Mn: 1.4%; Fe: 0.38%; Ce: 0.1%; La: 0.08%. The balance is aluminum and trace impurities, of which the total mass percentage of trace impurities is less than 0.6%.

The preparation method of the above-mentioned aluminum alloy for casting includes the following steps:

S1: Calculate and weigh pure manganese, pure iron, pure aluminum, Al-Ce alloy, and Al-La alloy as raw materials according to the mass percentage of raw materials;

S2: Put the flux in the crucible, then add the pure aluminum block that has been preheated to 200-250℃; when the crucible pot temperature rises to 1260-1300℃, add the pure manganese block that has been preheated to 400-450℃; the crucible pot temperature Raise the temperature to 1600~1650℃ and add the pure iron block that has been preheated to 500-550℃; after all the above raw materials are melted, lower the crucible temperature to 730~740℃, add the Al-Ce alloy that has been preheated to 150-200℃ , Al-La alloy, and stir evenly for refining, degassing and heat preservation for more than one hour to obtain alloy liquid;

S3: When the temperature of the crucible pot drops to 690-700°C, the alloy liquid is poured into the casting mold cavity to obtain an ingot.

Claims (5)

1. The aluminum alloy for casting is characterized by comprising the following components in percentage by mass:

manganese: 1.0% -1.8%; iron 0.3% -0.5%; 0.1 to 0.3 percent of rare earth element; the balance of aluminum and trace impurities, wherein the total mass percent of the trace impurities is less than 0.6 percent.

2. The aluminum alloy for casting as recited in claim 1, wherein: the alloy consists of the following components in percentage by mass:

manganese: 1.5%; iron 0.4%; 0.3% of rare earth element; the balance of aluminum and trace impurities.

3. The aluminum alloy for casting according to claim 1 or 2, wherein: the rare earth element is one or two of La and Ce.

4. The method for producing an aluminum alloy for casting as claimed in claim 1, comprising the steps of:

s1: according to the mass percentage of the raw materials, pure manganese, pure iron, pure aluminum and aluminum rare earth alloy serving as the raw materials are calculated and weighed;

s2: putting flux into a crucible, and then adding preheated pure aluminum blocks; adding preheated pure manganese blocks when the temperature of the crucible pot rises to 1260-1300 ℃; heating the crucible pot to 1600-1650 ℃ and adding preheated pure iron blocks; when the temperature of the crucible pot is reduced to 730-740 ℃ after the raw materials are completely melted, adding preheated aluminum rare earth alloy, uniformly stirring, refining and degassing, and preserving heat for more than one hour to obtain alloy liquid;

s3: and pouring the alloy liquid into a casting mold cavity to obtain an ingot when the temperature of the crucible pot is reduced to 690-700 ℃.

5. The method for producing an aluminum alloy for casting according to claim 4, wherein: in the step S2, the pure aluminum block is preheated to 200-250 ℃; preheating a pure manganese block to 400-450 ℃; preheating a pure iron block to 500-550 ℃; the aluminum rare earth alloy is preheated to 150-200 ℃.