JPS61153243A - Production of aluminum alloy - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application: The present invention relates to improved alloy additive packs and methods for producing aluminum-based alloys, and in particular to alloy packs and methods for producing aluminum-based alloys. .

Prior Art: Until now, when producing aluminum-based alloys, the molten aluminum was initially in a high purity state. Additionally, special alloying additives are added to the substantially pure aluminum melt to obtain the desired chemistry.

Selectively aluminum scrap is mixed into the aluminum melt and a homogeneous melt match is initiated. Based on the match results, additional alloying material is added to the aluminum melt and homogenized in the melt. be done. The melt is then cast to form an imbit or the like.

The method of charging alloying additives to molten aluminum rarely involves the addition of powdered alloying materials, such as powdered iron. An alternative and commonly commercially available method for adding alloying additives to a molten aluminum bath or melt is by placing briquettes of alloying additive into the melt. Known briquettes are a mixture of aluminum and alloy materials.

The briquettes are first weighed so that the appropriate amount of alloying additive can be added to the melt. next,
The briquettes are dropped or placed into the melt. The briquette form of alloying additives tends to soak into the melt, disintegrate, and further dissolve. Therefore, homogenization of the alloy material in the melt is promoted.

Prior art patents teaching methods for adding alloys to molten metal baths, particularly aluminum baths, include Bro.
No. 3,592,637 published on July 13, 1971 under the name of VRN) et al. This patent teaches that a blended mixture of aluminum and an alloying additive selected from an extensive list of aluminum-based alloy additives can be added to a molten metal bath.

This mixture, as described in this patent specification, improves the ability to add alloying additives to the molten aluminum bath.

Other methods for adding drugs (as opposed to metal additives) to molten steel melts have been suggested. This suggestion, filled with limited states of information and belief,
It consists of placing agents such as reducing agents and desulphurizing agents in a steel can. Silica was also included as an alloying additive.

The can itself essentially consists of a portion of the steel melt. The can and its contents are thus submerged in the steel melt, melted and homogenized.

Although various prior methods and additives have been successful to varying degrees, there is no way to add alloying additives and materials to molten aluminum, particularly through the melt, in a manner that reduces the expense of alloying additives. What is necessary remains the same.

Operation: In principle, the invention thus consists of an improved method for producing aluminum-based alloys by introducing prepacked alloying additives into a molten aluminum melt. Pre-packed alloy additives consist of an aluminum container that encloses a volume of alloy material, typically in the form of a powder, fill, lump, solid or granule. It has been discovered that the addition of alloying material to an aluminum container improves the dispersion of alloying additives contained within the aluminum container throughout the melt. Additionally, a dispersant can be included within the container. Such dispersants are
It can be a gas forming agent that tends to displace the contents of the container once it is placed in the melt.

Preferably, the melt is stirred before and after charging the additives. Also, the size of the powder can be optimized, for example.

An advantage and object of the method and product according to the invention is that precisely stoichiometric quantities or unit weights of alloy materials can be prepacked.

Another object of the invention is to obtain an alloy pack in which advantageous FC can be handled, stored and added to aluminum melts.

Another object of the present invention is to obtain an aluminum-based alloy additive that is prepacked for storage and use as desired or needed.

Yet another object of the invention is to have a long shelf life;
It is an object of the present invention to obtain a method and product for producing an aluminum-based alloy additive pack that is stable and inexpensive for manufacture and maintenance until use of the alloy material is required.

The above and other objects, advantages and embodiments of the present invention will become clearer in the following description.

Examples: The present invention is particularly useful for producing aluminum alloys. The invention therefore relates to a method in which the aluminum melt can receive alloying additive materials. Furthermore, this material is mixed with a melt to obtain a generally homogeneous alloy, which can be further cast. One important embodiment of the invention is its use in alloy additive containers made from aluminum or aluminum-based alloys. The container can be more or less rigid and can therefore be manufactured from sheet in the form of an aluminum can as illustrated in FIG. The container can also be more or less flexible and can therefore be manufactured from aluminum foil, for example as described in FIG. 2.

Thus, with reference to FIG. 1, cylindrical aluminum cans are typically manufactured from aluminum-based alloy sheets;
and has a cylindrical wall surface 10, a top closure surface 12 and a complete bottom closure surface 14, which cylindrical wall surface, top closure surface and complete bottom closure surface combine to define a closed container. In fact, the size of the container ranges from approximately 5.08 to approximately 1.27 microorganisms in diameter.
m (approximately 2 to % inches) and height approximately 5.08 cm to approximately 1.2 cm
It can be on the order of 7c* (approximately 2-% inches).

The container is advantageously sized to hold a unit amount of alloying additive material, such as a charge of about 1 pound of manganese, and this size can be varied to suit needs. can. Containers are generally hermetically and watertightly sealed to avoid contamination of the contents of the container.

The container may be filled with aluminum additive materials such as iron, manganese, chromium, titanium, copper, strontium, lead, bismuth or other aluminum-based alloys alone or in combination with each other and/or aluminum. Filled with a combination of For example, the container shown in Figure 1 can have a fixed weight of iron particles alone or together with some manganese particles. The particles are
Depending on the material and the purpose for including it as an alloying additive, it can be in the form of chrysanthemums, powders, fillers, granules or solids. Particle size is important. For example, for the addition of chromium, 140 methoxy powder was found to be optimal.

Other agents such as dispersants, spheronizing agents, nucleating agents, fluxing agents, modifiers and other agents can be incorporated alone or in combination in an aluminum container. It is important that the container is made from an alloy base material, namely aluminum.

In practice, identification of the contents of each can can be achieved by imprinting or printing on the outside of the can. Color coding may be provided to identify the contents of the can or to identify the common type of alloying additive. The cans are preferably sized and filled with specific unit quantities of alloy material to facilitate compact handling. Therefore, units of cans can advantageously be added to the aluminum melt.

FIG. 2 discloses an alternative embodiment of a container or pack that can be used as an alloy additive pack to practice the present invention. The pack of FIG. 2 is an aluminum foil pack made from a foil or sheet material that is substantially less rigid or flexible than the material forming the container of FIG. This less rigid container can be manufactured from an aluminum alloy that is more flexible than the pack shown in FIG. 1, or can have a thickness less than that of the pack shown in FIG. .

Referring to FIG. 2, the pack consists of a foil 20 which effectively encapsulates a predetermined, metered amount of additives, such as iron, manganese, etc.

The pack is preferably sealed to prevent contamination of the contents. The pack is also sealed to the extent that it can serve as an effective means for storing the contents until use is desired. Furthermore, the contents can be in granular form, powder form, filler or other forms as mentioned. The contents of the pack constituting the present invention are not tightly packed, but rather loosely packed into the pack to facilitate the dispersion of the alloying additive into the melt and subsequent addition to the melt. is preferable. However, in some cases the contents may advantageously be compact or in solid form. For example, it has been found that strontium aluminum additives are optimally maintained in solid form.

When carrying out the present invention, as shown in FIG.
maintained in a manner known to those skilled in the art. The aluminum melt is maintained at a sufficiently elevated temperature that several vessels 18 containing alloying material can be added to the aluminum melt. The determination of the number of containers and their contents to be added to the melt is established by analysis or assay of aluminum in the crucible and calculation of the final desired assay of aluminum. Therefore, filling needle calculations will be required in manufacturing. Once this calculation is completed, the number and composition of alloying additives and therefore the number of containers of alloying additives are known from the calculation.

Furthermore, this additive can be added to the melt simply by placing the aluminum container and its contents into the molten aluminum in a crucible, in particular crucible 16. Accordingly, the puck 18 is prepacked as described above and added to the melt in the crucible 16, so that the puncture 18, including the container for the puck, is melted and homogenized to form the desired alloy. Since the melt is aluminum metal and the container is made from aluminum, the addition of the contents of the container is improved. This is because aluminum foil or sheet can be easily and controllably melted and subsequently (
- This is because it is added to the furnace crucible 16. By controlling the size, shape, and wall thickness of container 1B, alloy processing can be further optimized.

Such optimization is currently an empirical process.

In practice, the pack is dropped into or otherwise immersed in the melt. Preferably, the pack tends to sink into the melt, with the pack walls still dissolving, and the contents of the pack being dispersed as it passes through the melt. However, in some cases, the specific gravity or density of the container and its contents will be less than the specific gravity or density of the melt. In such a case, the container and its contents will float. This does not have a detrimental effect on the method of the invention since the pack still dissolves and the contents are dispersed. However, if the filled container or pack floats, it is preferred to use mechanical means to submerge the pack in the melt.

It was found that in all cases the melt had to be stirred before and after addition of the J additive.

The melt is stirred to such an extent that the contents separated from the container below the melt surface are dispersed through the melt without reaching the surface.

Tests show that not stirring the melt can actually eliminate the benefits of the process. Therefore, stirring is an important step in this method.

It should also be noted that each pack can contain a single alloying additive or a mixture of alloying additives depending on the desired requirements. One of the most common desired additives incorporated into packs according to the invention is:
It is the iron that acts as a hardener for the aluminum to be cast. Importantly, none of the additives need be coated. Therefore, the filler or particles are not coated in a special container.

In addition to alloying additives, various other alloying agents may also be included within the pack. For example, spheroidizing agents, modifying agents,
Nucleating agents, fluxing agents or other aluminum-based agents or combinations thereof can be included in the pack. Additionally, dispersants can be included. For example, the pack can contain hexachloroethane in powder form together with special alloy powders.

Additionally, when the container or pack is added to the melt, the hexachloroethane decomposes to form chlorine gas, which effectively disperses the powder or granular material as it passes through the melt.

The idea of the invention will now be elaborated on by several experiments: Experiment N011 - A small charge of 99.7% pure aluminum is melted at approximately 1300 degrees Fahrenheit.
Maintain at a temperature of A loading of 1% by weight of iron was added in the form of 1100 mesh hydrogen reduced iron powder injected onto the surface of the aluminum melt. The iron powder sintered together on the surface of the aluminum melt, leaving an oxidation reaction there. The oxidation reaction was observed by flushing the iron. Therefore, by simply adding iron powder to the melt,
It was determined that this did not result in a good alloying process.

Experiment N002 - An experiment was conducted using an aluminum can filled with iron powder. Iron powder reduced by hydrogen 5.37
11 to 4 with a thickness of approximately 0.003 儒 ([1,001 inches)]
The deposit was packaged in two layers and heated in a cylindrical die to form pellets approximately 2.54 cm (approximately 1 inch) thick and approximately 0.32 m (% inch) thick. It was immersed in 537 g of a 99.7% aluminum melt by pressing. After 5 minutes, the melt was tested with a carbon rod,
Stir slightly. No iron powder was detected at the bottom of the crucible. After 10 minutes, a spectrophotographic sample was injected and the mixture was determined to be substantially homogeneous.

As part of the experiment, 404 F of aluminum melt was produced.
The temperature was maintained at approximately 704.4°C (approximately 1300°F'). A charge of 4 g of iron powder and 0.51 g of hexachloroethane wrapped in aluminum foil was melted in the form of a pellet approximately 2.54 c+a (approximately 1 inch) thick and 11.32 crrL ('/B inch) thick. added to. The packing t was dense enough to sink into the melt by gravity. After about 3-4 seconds,
A foaming effect was observed. After 5 minutes, the melt was cast and no appreciable deposits of iron powder were found at the bottom of the crucible. In conclusion, iron was properly dispersed as an additive alloy.

The experiments have confirmed that aluminum packs of suitable size and shape that enclose the additives are an advantageous method of loading the additives into the aluminum melt. Preferably, the contents of the pack are in such a form that they react with the melt. This is determined empirically and depends on the particle size, surface morphology and surface chemistry of the particles. The pack can generally have a small amount of content, ie, a sample size of about 1 pound or less. The pack can be designed to such an extent that the pack and its contents are submerged in the melt.

Although the packs can contain several alloying agents, a single alloying agent may be mixed into each pack, and thus additional packs may contain various alloying additives to form composite alloys. It is preferable to be able to form . It has also been found that it is important to maintain the aluminum melt in a molten state and add packs of alloying material.

Although preferred embodiments of the invention have been set forth, the invention is to be limited only by the claims and the like.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an aluminum container containing alloying additives, FIG. 2 is a perspective view of an optional container designed and manufactured from aluminum foil material and also containing alloying additive material, and FIG. The figure is a schematic diagram illustrating the process steps implementing the improved method according to the invention. 10... Cylindrical wall surface, 12... Upper closed surface, 14.
...bottom closed surface, 16...crucible, 18...pack, 20...foil

Claims (1)

[Claims] 1. An aluminum-based alloy is prepared by: (a) forming an aluminum melt; (b) maintaining the melt in a molten state; (c) adding at least one pre-packed alloy additive pack; In an improved method of manufacturing iron, manganese, chromium, titanium, copper and other aluminium-based alloys in the form of powders, fillers or granules to which this pack is not applied, by charging them into the melt; an aluminum container enclosing a volume of alloy material from the group consisting of the combination; (d) the pack and the contents of the pack are placed in a melt by maintaining the melt in the molten state for a sufficient period of time; A method for producing an aluminum-based alloy, comprising: melting; and (e) casting the molten alloy. 2. The pack also includes alloying agents selected from the group consisting of fluxing agents, modifiers, spheroidizing agents and other aluminum-based agents and combinations thereof. Method. 3. Aluminum containers generally consist of cylindrical cans,
A method according to claim 1. 4. A plurality of packs etc. includes the step of combining a predetermined amount of alloy material into the melt.
The method described in section. 5. The method of claim 1, wherein the pack also includes an agent for dispersing the alloy material into the melt. 6. The method according to claim 5, wherein the agent for dispersion is hexachloroethane which forms chlorine gas to disperse the alloying agent in addition to the melt. 7. The method of claim 4, wherein the packs have equal unit quantities. 8. The method according to claim 1, which includes the steps of stirring the melt before and after charging the additive pack.