Alloy Steel vs. Stainless Steel

For those choosing metals for various products, terms like “stainless steel” and “alloy steel” may be referenced simultaneously, or possibly interchangeably. And indeed, with how commonly used stainless steel is, it does make sense that these terms would frequently be conflated. However, the difference between alloy steel vs. stainless steel is actually important to understand, as these can refer to different metals with very different characteristics.

At Polished Metals, we’re known for our expertise in polished stainless steel products. While we don’t work with other types of alloy steel, we’re frequently asked about them for various projects. How do these terms for metals differ? We’re exploring that question in today’s blog post.

What Is Stainless Steel?

Stainless steel is an alloy primarily comprising iron and chromium, commonly with the addition of other metals like carbon, nickel, silicon, manganese, and more. Stainless steel must contain a minimum of 10.5% chromium, but most types of stainless steel will include significantly more—usually around 16–18%. 

Stainless steel is favored as a metal alloy thanks to its many attributes, including excellent strength and superior resistance to corrosion, tarnishing, and rust. It is one of the most commonly used metals in the world, and most people will see numerous examples of stainless steel in their everyday lives.

What Is Alloy Steel?

“Alloy steel” is a common term that is both easy and somewhat difficult to define. At its most basic, an alloy steel is simply any type of steel that has been alloyed—that is, mixed together—with some other element to form a different metal variety. 

That said, the term “alloy steel” is somewhat of a misnomer. This is because steel itself is already an alloy of iron and carbon. This combination gave the metal many advantageous properties that drove numerous advances throughout history. However, steel was further improved in various ways for specific purposes, often by adding a third element (or more).

Thus, alloy steel generally refers to any steel variety that has been somehow enhanced beyond plain steel—usually through the addition of a third metal, but not always.

Alloy Steel vs. Stainless Steel

knives made from damascus steel, a non stainless steel alloy

To put all of this together, the terms alloy steel vs. stainless steel can be differentiated much like rectangle vs. square. “Stainless steel” is a specific family of steel alloys; however, not all steel alloys are stainless steel.

Common non-stainless alloys of steel include the following:

  • Carbon steel – Another somewhat confusingly named alloy that is simply steel with a significantly higher than normal carbon content. Carbon steel may be used for cookware as well as in construction or manufacturing projects.
  • Damascus steel – A steel that includes a high carbon content, and often includes nickel along with metals such as vanadium. This alloy has a distinctive appearance.
  • Molybdenum steel – An alloy that is frequently used in aerospace and manufacturing due to its extreme heat tolerance.

Stainless steel is, of course, the most common steel alloy. However, steel alloys form a rich group of metals that are employed in many industries and for many incredible purposes all over the world.

Polished Metals Covers All Your Stainless Steel Needs

While we do not work with other types of alloy steel at Polished Metals, we’re renowned worldwide for our best-in-class stainless steel finishing capabilities. Our team works with a host of stainless steel varieties and we maintain a broad selection of products able to be polished by our experts in-house.

No matter what your needs are, Polished Metals is your trusted resource for precision, quality, and professional results, every time. If you have questions about our inventory or have custom metal finishing needs, please reach out to us.