What is aluminum products

Below is an overview of aluminum products, how it is represented in Europe [1, 2], with reference to the European standards.

Aluminum and aluminum alloys

For aluminum products include products and semifinished products made of unalloyed aluminum and aluminum alloys, wrought and cast, and also the starting materials for their production – primary and secondary aluminum in the form of an aluminum, ingots, billets, etc.. P.

Unalloyed aluminum - aluminum without alloying elements, wherein the aluminum content is not less than 99,00 %.

Aluminum alloy - Aluminum, which contains alloying elements, wherein the aluminum content is greater, by weight of any of the other elements in the alloy, and aluminum content is not less than 99,00 %.

Alloying element - the metallic or non-metallic element, which is controlled within upper and lower limits in order to make aluminum alloy of some special properties.

Admixture - the metal present in the metallic or non-metallic element, which is not controlled by the minimum content.

Primary aluminum

Aluminum, which is produced by the electrolysis of alumina, called primary aluminum. The primary aluminum may be added a small amount of clean process scrap. The aluminum content in the primary aluminum is not less than 99,7 % (drawing 1).

Primary aluminum production [2]

Primary aluminum is, usually, raw material for the production of this type of aluminum products, as aluminum semi-finished products – sheets, stripes, tubes, Profiles and t. P. It is also a starting material for cast alloys, are used for the manufacture of products especially responsible, such as wheels and chassis components of motor.

In the foundry primary aluminum producer liquid aluminum is subjected to various types of treatment with the, so that it can meet the established technical requirements:

  • alloying, i.e. addition of alloying elements in pure form or in the form of ligatures, to obtain a predetermined chemical composition. Ligatures may contain up 65 % alloying elements
  • Purification - application of flux or filters
  • Dehazatsyya
  • Casting into ingots (or, sometimes, into shaped castings)
  • Supply of aluminum in liquid form.

Ingots for remelting

Aluminum ingots for remelting (EN 576) are poured into open molds in the foundry, which is part of the primary aluminum producer, or casters horizontal casting. Most often they are used in the form of small ingots - ingots (figure 2).


Aluminum ingots, ingots for remelting

These ingots then follow two different routes to make aluminum products:

  • They are melted in a specialized foundry profile in ingots, billets for rolling and pressing plants.
  • Profiled bars billet, such as rolling ingots, slabs and ingots-pillars for pressing also generally bottled in their own foundries rolled or pressed producers

profiled bars

Profile aluminum ingots are the generic name for rolled slabs (EN 487), ingots-billets for pressing (EN 486) and cast blanks for forging (EN 604). They are the source material for manufacturing semi-finished – products, which is the starting material for the manufacture of finished articles. They are produced using a vertical semi-continuous casting process,, which is called direct chill casting (Figure 3).

Semi-continuous vertical direct cooled casting [3]

 

This type of aluminum products, as aluminum tires with a large cross-section, typically produce at similar horizontal continuous casting machines.

rolling ingots

The rolled ingots have a rectangular cross-section (up to 0,6 x 1,8 m). They can be up to 6 meters and weighing up to 14 tonnes. Some of the larger mills can produce and / or handle bars with a cross section up 0,6 x 2,25 m, up to 9 meters and weighing up to 30 tonnes. Rolled ingots are the raw material for sheet aluminum products: aluminum sheets, strips and foils.

Rolled slabs [4]

Rolled aluminum slabs [8]

Extrusion ingots and billets

Extrusion ingots (pillar ingots) are the starting material for extruded products (extruded profiles, bars, pipe, wire). Most extrusion ingots are cylindrical. Therefore, they are often called pillars (figure 5). These pillars have a diameter of 80 by 500 mm, sometimes more 600 or even 1000 mm. Usually their nominal diameter is a multiple of an inch (25.4 mm), eg:

  • 5 inches - 127 mm
  • 6 inches - 152 mm
  • 7 inches - 178 mm
  • 8 inches - 203 mm
  • 9 inches - 228 mm
  • 10 inches - 254 mm.

Directly into the extrusion press container was charged dimensional segments of these pillars – blank – length 500-1000 mm, depending on their diameter, called blanks. These blanks are obtained in advance by cutting an ingot-column into measured lengths or cut from a heated column immediately before loading into a press (Figures 5 and 6).

Ingots-pillars at the entrance to the heating furnace of the aluminum extrusion line [5]

Heated billet before loading into the container of the extrusion press [5]

Aluminum extrusion billets

Cylindrical hollow blanks (for example, with an external diameter 510 mm and an inner diameter 160 mm) are used for pressing seamless pipes through a mandrel.

Large profiles with a cross-sectional width of up to 800 mm and relatively small height (up to 100 mm) are made from a rectangular blank.

Molded preform forging

Cast billet for forging produced by continuous casting on the orders of forging enterprises. Diameter of the forging workpiece can reach 1 m. However, most forgings are made from blanks, which are obtained from ingots-pillars [2].

The cast tape

The cast tape - is the starting material for the production of sheets and strips, as well as products, are prepared by extrusion of the shock. Cast strip produced in a variety of machines for continuous casting, as well as machines for casting and rolling.

Rolls finished aluminum sheets

Continuously cast and rolled rod

Continuously cast and rolled bars are produced using special continuous casting machines (Figure 7). Similarly the compressed wire rod is used as a raw material for wire drawing, which refers to the production of cold-rolled aluminum.

The principle of continuous casting and rolling of aluminum rod according to the technology of the company Properzi [6]

 

Aluminum - steel deoxidizer

Aluminum is used in the production of steel for deoxidization, grinding grain, reducing the nitrogen content and alloying. Most aluminum, which is used in steelmaking, is produced from scrap. These aluminum products are manufactured in the form of aluminum metal (ingots or rods), as well as the aluminum fraction, pellets, small ingots, chopped wire, briquettes and other convenient for introduction into the furnace forms, such as wire coils. This aluminum products supplied in bulk or packaged in bags or packages.

The purity of aluminum alloys for deoxidation of steel is generally not less than 95 %. The main impurities are zinc, lead, copper, magnesium,, lead and manganese. Aluminum wire coils typically made of pure aluminum 99 %.

liquid aluminum

Liquid aluminum (EN 577) are transported to foundries in special automobile containers (Figure 9). This approach is becoming more common, as it allows to save energy, which goes to the melting of ingots.


Transportation of liquid aluminum [4]

Secondary aluminum

New (technological) and old (used) aluminum scrap is the initial charge for the production of secondary aluminum. So-called "secondary smelters" old mixed scrap or aluminum scrap and Technology prepared so-called secondary aluminum alloys. These alloys are supplied to foundries in ingots for remelting or liquid metal. These foundries producing aluminum products in the form of castings, which are widely used, for example, in the automotive industry. Secondary aluminum is also on the production of ingots, bars and granules for steel deoxidation.

Sorted aluminum scrap, consisting of wrought alloys, again can be applied to the production of plants “the semi” aluminum products – semis. An example is the aluminum cans for beer and soft drinks, are widely recycled worldwide.

Scrap aluminum cans

aluminum semi-finished products

What are semi-finished products?

Polufabrikaty- is "semi-finished" products are aluminum, that has been subjected to certain treatments and which must be further processed to manufacture products, which is already completely ready for use [1]. Semi-finished products include, Method of manufacturing a pressure treatment, and, rarely, injection. Ingots for further processing by pressure and do not apply to semi-finished products .

Most often, "Semi-finished" - are the products, which is made by hot or cold processing (extrusion, shoeing, cold or hot rolling, dragging). A common characteristic of these processes is, that during their metal - aluminum - is exposed to plastic deformation. Therefore, the aluminum alloys, which are intended for these processes are called "wrought alloys" (EN 573).

The high processing ability of aluminum gives a wide variety of aluminum parts and products in size and shape: from foil thickness 6 micrometers and a width 2 meter to several meters of plates in width for use in aircraft construction and shipbuilding, as well as in mechanical engineering. aluminum extrusion capable of producing a compressed product thickness of pipe 0,8 mm for the electronics industry to profile width 800 mm for modern high-speed trains.

rolled aluminum

Rolling - a technology, which is usually used for the manufacture of such aluminum products, as the band, sheets and foil. Before, as the metal hot rolled, from ingot surface layer is removed, which was formed during its molding. The ingot was then heated in a furnace to rolling temperature. During rolling the product is cooled by special emulsions. During each pass through the mill rolls is a significant reduction in strip thickness. Depending on the requirements to the final dimensions and properties of the hot rolled strip may be further processed to cold rolling mill to a thin sheet or foil. Features and technical terms of delivery for this set of aluminum products in the European Standard EN 485.


aluminum sheets


Aluminium foil

Extruded products

Unlike other processes for the production of semi-finished products, methods of extrusion (pressing) of aluminum alloys make it possible to produce the most diverse cross-sectional shapes - from simple solid profiles to complex profiles with several cavities.. However, it should be noted, there are some limitations, which derive from the specific conditions of the extrusion process. Aluminum profiles with large differences in thickness of shelves and walls, and profiles, in which the wall thickness is too thin compared to the overall cross-sectional dimensions, requires significant effort and cost for manufacturing a pressing tool, provide stability and effective compression tension straightening.

Extruded aluminum profiles

Available profile sizes (EN 755 и EN 12020) depend on the material (aluminum alloy), and the diameter of the circle described Profile.

cold drawn products

Cold drawn product - this product, which is obtained by pulling the material through the matrix (Figure 12).

Drawing of a bar (a) and a pipe (b)

The starting material for manufacturing cold-, which are obtained by cold drawing, are extruded rods and tubing, and rolled or cast billet, which are obtained by continuous casting and rolling. It is technically possible to expose cold drawn and extruded profiles, however, it is considered uneconomical and therefore not used in practice.

Requirements for cold-drawn aluminum products specified in EN 754.

forgings

The usual dimensions of so-called open forging are: length - up to 5 m, width - to 2 meters and a surface area - up 2 m2. forgings, which were made into a closed mold, such as automobile wheels or bearing parts for aircraft and vehicles, characterized by high strength and toughness, and therefore they are used for heavy and critical components.

Forged aluminum suspension arm [6]

aluminum composites

Aluminum may be combined with other materials - metallic and nonmetallic - in the manufacture of composite materials. When aluminum metal is combined with, such as steel or copper alloys, they are usually connected by a pressure welding or friction welding.

Two-dimensional combination with aluminum nonmetals, for example, with plastic or wood, represent, so called, sandwich elements, which is manufactured by adhesive bonding or foam filling the space between the two outer layers of aluminum.

Boroaluminum composite (40 % boron fibers)

Semifinished sheet flooring

These products are made of aluminum sheet or strip through cold working, which includes plastic deformation. Examples of such aluminum products are:

  • The profiles of the sheets and strips, which are obtained by the method of roller bending (figure 16).
  • Profiles of strip, which are made by roller bending or drawing through a die; an example of such profiles are profiles for window blinds.
  • profiles, which is made by bending strips.
  • Welded walled tube, for example, for heat exchangers.
  • Spiral welded pipe.
  • Corrugated pipes (flexible pipes).

Production of aluminum profiles by roller bending [7]

Sources:

1. Global Advisory Group GAG – Guidance “Terms and Definitions”
2. Materials Aluminum Association Germany
3. Tom Hauge, Hydro Aluminium, IHAA Symposium 2014, New York
4. https://www.trimet.eu/en/produkte/lieferformen/fluessig
5. Materials of the Tecalex company (Spain).
6. TALAT Reading 3210: Continuous Casting
7. http://custompartnet.com/
8. Aluminium in Commercial Vehicle – European Aluminium Association – 2011