Overview

Aluminum is a remarkable metal, known for its versatility, workability, and lightweight properties. With a melting point that is high enough to be useful in a myriad of applications, it is no wonder that this element is the third most abundant in the Earth’s crust and the most used non-ferrous metal after steel. In this blog post, we will explore the melting point of aluminum, its implications for different aluminum alloys, the factors that affect this critical property, its applications, and how it compares to other metals.

Melting Point Chart of Aluminum Alloys

The melting point of aluminum is a fundamental property that affects its use in various industries. The melting point of pure aluminum is 660.32°C (1220.58°F). However, when other elements are added to make aluminum alloys, the melting point may change. The following is a melting point chart of eight series of forged aluminum alloys:

Note: data comes from Matweb.

These ranges indicate that the addition of alloying elements can significantly alter the melting point to suit specific applications.

Melting Points of Typical Aluminum Alloys

The eight major forged aluminum alloy series have some alloy grades that are widely used. The following table selects some of them to show the corresponding melting point range:

Note: data comes from Matweb.

Factors that Affect the Melting Point of Aluminum

Several factors can influence the melting point of aluminum and its alloys:

• Alloying Elements: The presence of alloying elements such as copper, magnesium, silicon, and zinc can raise or lower the melting point, depending on their interaction with aluminum.
• Impurities: Even trace amounts of impurities can affect the melting point. For instance, iron, which is often present as an impurity, can lower the melting point.
• Thermal History: The thermal history of the aluminum, including any previous heat treatments or processing, can refine the grain structure and affect the melting point.
• Processing Techniques: Different processing techniques, such as rapid solidification or powder metallurgy, can lead to non-equilibrium microstructures with varying melting points.

Applications of Aluminum’s High Melting Point

The high melting point of aluminum and its alloys makes them suitable for a range of high-temperature applications:

• Welding and Brazing: Aluminum’s high melting point allows for strong welding and brazing techniques, which are essential in the fabrication of complex structures and components.
• Heat Exchangers: The high melting point of certain aluminum alloys makes them ideal for use in heat exchangers, where they can withstand high operating temperatures without melting.
• Cookware: Aluminum’s high melting point is also beneficial in the manufacturing of cookware, ensuring that pots and pans can handle high cooking temperatures without risk of melting.

How Aluminum’s Melting Point Compares to Other Metals

When compared with other metals, the melting point of aluminum is not high. Here’s a comparison of the melting points of aluminum with a few other common metals:

This comparison shows that while aluminum has a lower melting point than metals like iron and steel, it is higher than zinc and many other metals. This places aluminum in a favorable position for applications that require a balance between high temperature resistance and workability.

In conclusion, the melting point of aluminum is a critical property that influences its use in various industries. Understanding the factors that affect this property and how it compares to other metals is essential for material selection and process optimization. Aluminum’s high melting point, combined with its other beneficial properties, makes it a versatile material for a wide range of applications.