How Stainless Steel Becomes “Stainless”

Stainless steel is classified as a steel alloy that contains chromium in quantities of at least 10.5%. What makes it stainless steel is a bit more complicated than that, though.

The Protective Layer

All stainless steel products, whether a stainless blind flange or something else, are protected by a passive layer of oxide. That oxide is formed on the surface of the steel by the interaction between oxygen and chromium. This keeps corrosive effects out and protects against rust. It makes stainless steel resilient to rusting and various other types of corrosion or damage that would normally occur in other kinds of metals or in regular steel under the same conditions. This doesn’t mean that stainless steel can never rust, but it takes a lot more damage or effort or time for it to rust.

If steel manufacturers want their stainless steel to be even more rust resistant, they will increase the levels of chromium in the steel during the production process. Stainless steel does not change colour or rust the way plain steel would since it is a protected alloy with chromium as part of its makeup.

How Stainless Steel Functions Different from Plain Steel

All stainless steel products are made using some chromium – at least 10.5%, remember, and that’s a substantial change over plain steel, so it is a substantially different metal. It is no wonder that its inherent properties are very different from plain steel.

The outer surface will not tarnish or stain over time, in contrast to plain steel which will. That protective layer and high chromium content means that every stainless steel product is much stronger than plain steel. The tensile strength is higher, which creates a more durable material that is better for use in structural applications. This stainless steel can also handle more extreme temperatures without weakening, and it is self-protected against corrosion.

One of the most amazing aspects of stainless steel is that it can heal itself. If it is scratched or otherwise damaged, the steel emits an oxide layer to form a new coating in that damaged area. No matter how the metal was fabricated, it will have that protective layer there that is exuded when necessary to safeguard the outer surface, and plain metal does not have any kind of protection on that level.

Use the Right Stainless Steel

There are many different grades of stainless steel, and the grade tells you how strong and how corrosion resistant the steel is. You will want to use a suitable grade for the kind of application you need it for. Talk to your stainless steel expert to find out which grade is best for your needs so that you get the most from your stainless steel purchase.

This will help you to get the right stainless steel product at the most affordable price, so you are not overpaying for steel and getting a higher grade than you need when a lower grade will work just fine for your purposes.