Stainless Steel vs Aluminum: 12 Differences between Stainless Steel and Aluminum (PDF)

Aluminum and Stainless steel are two widely used materials in various industries. Wherever lightweight is a requirement, aluminum seems to be a good metallic option. Stainless steel is widely used as a corrosion-resistant ferrous metallic alloy. In this article, we will explore 12 major differences between stainless steel and aluminum.

Stainless Steel vs Aluminum: Appearance

Stainless steel is shiny whereas aluminum usually has a dull texture. However, weather can change appearances. Still, stainless steel will be brighter as compared to aluminum.

Stainless steel vs Aluminum: Composition

Aluminum is non-ferrous metal whereas stainless steel is ferrous where iron is the main constituent element. Pure aluminum is metal but stainless steel is an alloy.

Stainless Steel vs Aluminum: Strength to Weight Ratio

Even though stainless steel is stronger than aluminum because of its almost one-third weight It is one of the preferred materials in the automobile and aircraft industries. Aluminum has approximately half the strength compared to that stainless steel. So, the strength-to-weight ratio of aluminum is better than stainless steel and this aspect makes aluminum a better choice in various industries.

Aluminum vs Stainless Steel: Corrosion Potential

In a normal environment, aluminum has very good corrosion resistance and does not rust. However, in some extremely acidic and base environments, it corrodes rapidly and can even result in catastrophic failure.

Stainless steel is an alloy of iron, chromium, nickel, manganese, and copper. The chromium is purposely added to generate a protective film and provide corrosion resistance. Also, as stainless steel is non-porous, it increases its corrosion resistance further.

Stainless Steel vs Aluminum: Thermal and Electrical Conductivity

When comparing both metals in terms of thermal conductivity, aluminum is better as compared to stainless steel. Because of this reason, aluminum is used widely for air conditioners and car radiators. However, stainless steel has high thermal resistance as compared to aluminum and thus can be used at high temperatures.

Aluminum has better electrical conductivity as compared to stainless steel.

Aluminum vs Stainless Steel: Cost

When comparing in terms of weight, Aluminum usually is costlier than stainless steel. However, when compared in terms of volume, due to low density, Stainless steel is costlier than aluminum.

Also, the aluminum refining process is less complex than producing stainless steel. This also reduces the cost of aluminum.

Stainless Steel vs Aluminum: Workability

Aluminum being soft is very easy to cut and form. On the other hand, Stainless steel is very difficult to form. For producing any customized shape, aluminum will take low energy and time as compared to stainless steel.

Aluminum vs Stainless Steel: Welding property

Aluminum is difficult to weld as compared to stainless steel. So, for applications involving an extensive amount of welding, stainless steel will be a better choice as compared to aluminum.

Aluminum vs Stainless Steel: Sparkability

While grinding stainless steel produces sparks whereas aluminum does not produce spark.

Aluminum vs Stainless Steel: Reactivity with food

Aluminum can affect the taste and color of certain foods. It is, therefore, stainless steel is preferred over aluminum in the food industry as stainless steel is non-reactive to foods.

Stainless Steel vs Aluminum: Occurrence

Aluminum is naturally available from bauxite ores. On the other hand, stainless steel is a fully man-made engineered alloy. Stainless steel is not naturally available.

Aluminum vs Stainless Steel: Magnetic Properties

Aluminum does not show magnetic properties but certain grades of stainless steel have magnetic properties.

Conclusion

Even though both aluminum and stainless have varying properties, both of them are highly useful materials. The selection between aluminum and stainless steel mainly depends on the application. So, the end-use dictates which material to be used for a specific application.