Stainless steel and aluminium may look quite similar – and in fact many people confuse the two – but there are actually a number of significant differences between them.
Firstly, aluminium is a natural element, whereas stainless steel is an alloy, consisting mainly of iron and chromium. The amount of chromium present in stainless steel can vary from 10 – 30%, depending on the grade, and it is what gives the metal its anti-corrosion and rust-resistant properties.
Aluminium is not as strong as stainless steel, which can be recycled almost indefinitely without any loss of strength. However, aluminium weighs about two-thirds less than stainless steel, which is why it’s preferred for the manufacture of aircraft and vehicle bodies. Stainless steel is heavy and strong, making it ideal for use in construction and any application where structural support is needed.
Aluminium has superior thermal conductivity to stainless steel, which is why it is often used for air conditioning units and car radiators. Stainless steel, however, can withstand much higher temperatures than that of its competitor, which tends to soften at temperatures over 200°C.
Aluminium is generally less expensive than stainless steel as it requires less processing. However, stainless steel’s durability and corrosion resistance often mean it is cheaper in the long term as it requires less maintenance and doesn’t need to be replaced as often.
Stainless steel is generally preferred for catering equipment and food utensils as it is chemically inert and does not react with food. Aluminium can react with very acidic food, such as tomatoes and wine, which may affect the colour and taste. Stainless steel cookware is popular because it doesn’t react with food, but it is a poorer conductor of heat than aluminium. For this reason, many manufacturers of stainless steel cookware coat the underneath of their pans with copper, making them thermally responsive while still being chemically inert.
If you’re looking for an instant way to tell the difference between the two, just grab an angle grinder! Stainless steel will spark when you grind it, but aluminium won’t.
Steelmor is a leading supplier and manufacturer of stainless steel in South Africa, and we look forward to chatting to you about how we can help you meet your product requirements.