What is the Difference Between Aluminum and Steel?

The main differences between aluminum and steel lie in their weight, strength, corrosion resistance, and thermal conductivity. Here is a comparison of the two materials:

Weight: Aluminum is less dense than steel, making it lighter. For two pieces of equal volume, steel is typically 2.5 times denser than aluminum.
Strength: Despite being at risk for corrosion, steel is generally harder and stronger than aluminum. Aluminum increases in strength in colder environments but is more prone to dents and scratches than steel. Steel is less likely to warp or bend from weight, force, or heat.
Corrosion Resistance: Aluminum has better corrosion resistance than steel due to its ability to form a protective oxide layer on its surface, which acts as an inert barrier against further corrosion. This makes aluminum more resistant to rusting compared to steel.
Thermal Conductivity: Aluminum is generally a better thermal conductor than steel and is often used in applications such as heat sinks. This means that aluminum is more effective at dissipating heat compared to steel.
Malleability: Steel is more rigid than aluminum, making it harder to work into different shapes, especially complex ones. This can be somewhat overcome by heating the steel to very high temperatures, but this adds cost and can affect the final product's quality.

When choosing between aluminum and steel, consider factors such as cost, the shape of the application, and its end use. The final application of the part will ultimately determine which material is most suitable, balancing the limitations and advantages of each.