Aluminum: Properties, Production, and Industrial Applications

Metal Classification by Density

Non-ferrous metals are primarily classified based on their most important property: density.

• Light Metals: Have a density between 2 and 5 Kg/dm³.
• Ultralight Metals: Their density is less than 2 Kg/dm³.
• Heavy Metals: Possess a density greater than 5 Kg/dm³.

Aluminum's Natural Source and Abundance

From Which Mineral is Aluminum Obtained?

Aluminum is obtained in nature primarily in the form of bauxite. This mineral is composed of aluminum oxide, iron oxide, silicon oxide, and water.

Regions of Bauxite Abundance

This mineral exists predominantly in tropical regions of the planet, for example, Northern Brazil.

Aluminum Production Process

Stages of Aluminum Production

The metallurgical production of aluminum occurs in two main phases:

1. Obtaining metallurgical-grade alumina.
2. Producing pure aluminum.

Forms of Aluminum from the Aluar Plant

Liquid aluminum, at over 800°C, is transported by thermally protected trucks. The metal then solidifies into various forms for different applications:

• Ingots for Molding: Used for products like pistons, tables, chairs, molds, etc.
• Bars for Extrusion: Ideal for items such as TV antennas, profiles, etc.
• Sheets for Lamination: Applied in products like road signs, sheets for car bodies, etc.

Primary vs. Secondary Aluminum

Understanding the distinction between primary and secondary aluminum is crucial for their respective uses:

• Primary Aluminum: Directly from electrolysis cells, it has a purity of between 99.5% and 99.8%. However, it possesses low mechanical resistance.
• Secondary Aluminum: Refers to homogeneous alloys that are created by adding other elements to improve the alloy's resistance and other desired properties.

Aluminum Alloys and Processing Conditions

A significant relationship exists between the metals used for aluminum alloys and the processing conditions of each alloy. For both deformation alloys (such as those used in rolling, forging, and extrusion) and casting alloys, the primary goal of adding alloying metals is to ensure the final alloy is optimally suited for its specific processing conditions and intended use of the materials.

For example, silicon added in different percentages markedly increases the fluidity during molding and enhances the hardness of aluminum without negatively affecting its corrosion resistance.

Ultralight Metals and Their Applications

What are some known ultralight metals and their most common applications?

(Information regarding specific ultralight metals and their applications was not provided in the original document beyond this question.)