Everyone knows what rust is and what it looks like, but do you know why it happens? Rust is an iron oxide that forms when iron combines with oxygen, hence the name. For this process to take place, you also need water.
When water connects with iron, a chemical reaction begins. The water mixes with carbon dioxide in the air to form a carbonic acid. This begins to eat away at the iron. While it’s doing that, some of the water breaks down into separated hydrogen and oxygen.
This lone oxygen then merges with the iron bonds to form iron oxide, which is the rust that you see. Liquids such as salt water and acid rain are more effective at creating rust as they are more corrosive properties.
Since steel is an alloy made of iron and carbon, it is prone to rust as well. This can be especially bad as it causes a breakdown of the steel itself, compromising strength and structural integrity.
But this doesn’t happen with stainless steel. Why?
Why Stainless Steel Doesn’t Rust
While stainless steel is made up of iron and carbon just like any other steel, it adds two crucial elements to the mix: chromium and nickel.
Chromium is not only what gives steel its shiny appearance, but it’s critical in rust prevention. Rather than reacting with the iron in the steel, oxygen is attracted to the chromium instead. This produces a film that protects the steel further, inside and out.
The nickel is there to help hold the chromium layer in place.
Can Stainless Steel Rust?
Theoretically, as long as there is enough chromium present, stainless steel can’t rust. However, there are ways to throw off the balance. If you cleaned a stainless-steel tool with a steel wool brush or you leave an iron pan in a stainless-steel sink, you may find rust begin to form.
This is because particles from the non-stainless item have rubbed off on the stainless steel, disrupting the balance and allowing rust to form.
The good news is it generally won’t penetrate far and can be removed through cleaning.
Also, stainless steel is still susceptible to chlorine and salty sea water.
Do I Need Stainless Steel?
You may be wondering why people don’t just use stainless steel for everything. Though it’s highly resistant to corrosion, it’s more expensive and a little more difficult to work with than standard steel. That’s why many manufacturers choose to only use stainless steel as needed.
When deciding between traditional steel with stainless steel, it’s helpful to consider the environment it will be used in. Will moisture, salt, and other corrosive materials be present?
Depending on the use, there are other ways of preventing and reducing rust in traditional steel as well. This includes the application of paint, grease, or anti-corrosive coatings.
At Ever-Roll, we work with quality steel, stainless steel, and aluminum to meet the needs of our customers. Whether you need tube bending, wire fabrication, or burner rings, our products are built to last.
Contact us today to make an order or discuss your options.