CARBON STEEL VS. STAINLESS STEEL

While there are hundreds of different grades of steel, generally these fall under two main categories: stainless steel and carbon steel. When embarking on a project requiring steel, ensuring you choose the right type is of the utmost importance. This blog will teach you everything you need to know about carbon steel vs. stainless steel.

Steel is made of iron and carbon, and this is the same across stainless and carbon steel. What makes stainless steel different is the presence of chromium. To be stainless, the steel must contain at least 10.5% chromium. This is compared to carbon steel, which is made of iron and carbon with very few other materials present in the alloy. For this reason, carbon steel is sometimes referred to as a low-alloy steel.

What Are The Properties Of Carbon And Stainless Steel?

When it comes to carbon and stainless steel, there are many properties to be aware of.

Rust

Because of the chromium content, stainless steel has great corrosion-resistance properties. When chromium attaches to oxygen, a protective layer of chromium oxide is created, which will protect any exposed metal from further corrosion.

As such, stainless steel does not rust (the clue’s in the name!), so it’s ideal for outdoor use or when it’s exposed to the elements. On the other hand, carbon steel will rust, because it doesn’t contain enough chromium.

Mechanical Properties

Within carbon steel, there are steels with a high, medium and low amount of carbon. The amount of carbon will affect its cost, how easy it is to work with and its ductility (how much it will stretch and bend without cracking).

Low carbon steels are highly ductile, and instead of breaking under stress, they’ll deform. This makes them easier to work with. You’ll commonly see low carbon steels in car panels.

Medium carbon steels are used in instances where a bit more strength and toughness is required. You’ll find medium carbon steel in gears, axles and railway tracks, amongst other things.

The higher the carbon content, the stronger and harder the steel will become. So, high carbon steels are very hard, but brittle. Knives and tools are often made of high carbon steel, but these can crack easily if put under a high amount of stress.

Which is Cheaper?

Generally, stainless steel is more expensive than carbon steel. This is down to the presence of additional elements such as chromium.

Appearance

Stainless steel is the more aesthetically pleasing of the two. There’s a number of different finishing options available for stainless steel, so it’s a better choice if it’s being used in a more decorative way, or where people are going to see it. Carbon steel will also rust eventually, and will require repainting.