Classification of aluminum alloys

Classification of aluminum alloys

The classification of aluminum alloys can be carried out according to two dimensions, namely manufacturing process and chemical composition;

Based on manufacturing process: can be divided into casting and wrought processing;

Based on chemical composition: Aluminum alloys can be classified into two main categories: wrought alloys and casting alloys. Wrought alloys are further classified into 8 different series based on their primary alloying elements. The most common series are 1xxx, 2xxx, 3xxx, 4xxx, 5xxx, 6xxx, 7xxx, and 8xxx. Casting alloys are classified into 3 different series: 2xx.x, 3xx.x, and 7xx.x.

1050 wrought aluminum sheet

Classification of aluminum alloys is established by the International Alloy Designation System (IADS), based on the classification developed by Aluminum Association of the United States.

This Classification of aluminum alloys is accepted by most countries.

What is a wrought aluminum alloy

Wrought aluminum alloy is an aluminum alloy material manufactured by a forging process. Forging is a metalworking process in which a metal material is plastically deformed by the application of pressure to obtain a desired shape and size.

Forged aluminum alloy has excellent mechanical properties such as high strength, high toughness, good corrosion resistance and heat resistance, so it has a wide range of applications in the manufacture of high-strength, lightweight, high-reliability parts and structural parts.

The manufacturing process of wrought aluminum alloy includes hot working and deformation working. During the manufacturing process, the aluminum alloy is heated to its plastic temperature, then placed in a mold and deformed by applying pressure to achieve the desired shape and size.

Common wrought aluminum alloys include 6061, 7075, 2024, etc. They have good processability and formability, so they are widely used in the manufacture of aviation, aerospace, automotive, construction and sports equipment.

aluminum alloy rolling workshop

Classification of wrought aluminum alloys(chemical composition)

Meaning of wrought aluminum alloy grades

Each wrought aluminum alloy has four digit number.

The first digit indicates the alloy group according to the main alloying elements

The second digit indicates modification of the alloy or impurity limits.

Original (basic) alloy is designated by “0” as the second digit. Numbers 1…9 indicate various alloy modifications with slight differences in the compositions.

In the alloys of the 1xxx series the second digit indicates modifications in impurity limits: 0 means natural impurity limit, 1…9 indicate special control of one or more impurities or alloying element.

The last two digits identify aluminum alloy or indicate the alloy purity.

In the alloys of the 1xxx series the last two digits indicate the level of purity of the alloy:

1070 or 1170 mean minimum 99.70% of aluminum in the alloys, 1050 or 1250 mean 99.50% of aluminum in the alloys, 1100 or 1200 mean minimum 99.00% of aluminum in the alloys.

In all other groups of aluminum alloys (2xxx – 8xxx) the last two digits signify different alloys in the group.

What is a casting aluminum alloy

Casting aluminum alloy is a type of aluminum alloy that is produced by casting process, which involves pouring molten metal into a mold to achieve a desired shape and size.

Cast aluminum alloys have a wide range of mechanical properties and can be produced in different shapes and sizes, making them suitable for a variety of applications.

cast aluminum alloy

Casting aluminum alloys are typically composed of a mixture of aluminum and other elements, such as copper, magnesium, zinc, and silicon. The exact composition of the alloy can be tailored to meet specific performance requirements, such as strength, ductility, and corrosion resistance.

Classification of cast aluminum alloys and the significance of grades

• 1xx.x Aluminum 99.0% minimum;
• 2xx.x Copper (4%…4.6%);
• 3xx.x Silicon (5%…17%) with added copper and/or magnesium;
• 4xx.x Silicon (5%…12%);
• 5xx.x Magnesium (4%…10%);
• 7xx.x Zinc (6.2%…7.5%);
• 8xx.x Tin;
• 9xx.x Others.

Data Sources：Classification of cast aluminum alloys

Every cast aluminum alloy is detailed by means of a four digit variety with a decimal factor setting apart the third and the forth digits.

The primary digit suggests the alloy organization according to the main alloying element.

The second digits identify aluminum alloy or indicate the alloy purity.

In the alloys of the 1xx.X series the second digits indicate the level of purity of the alloy – they may be similar to the two digits to the proper of the decimal point inside the minimum attention of aluminum (in percents): one hundred fifty.0 means minimal 99.50% of aluminum in the alloy, 120.1 manner minimal ninety nine.20% of aluminum in the alloy.

The final digit suggests the product form: casting (distinct through “zero”) or ingot (targeted by using “1” or “2” relying on chemical composition limits.)

A amendment of the authentic alloy or impurity limits is indicated by a serial letter earlier than the numerical designation. The serial letters are assigned in alphabetical order beginning with A however omitting I, O, Q, and X (the letter “X” is reserved for experimental alloys).