Stainless steels are defined as those containing at least what percentage of chromium?

Stainless steels are classified based on their chromium content, which is crucial for their ability to resist corrosion. The minimum percentage of chromium required to be classified as stainless steel is approximately 10.5%. At this level of chromium, a protective layer of chromium oxide forms on the surface of the steel, enhancing corrosion resistance and the overall durability of the material.

Choosing 10% as the threshold makes sense because it effectively balances performance in terms of corrosion resistance while still allowing for the desirable properties of steel, such as strength and ductility. This foundational understanding of the alloying characteristics of stainless steel underpins much of the industry’s practices in selecting materials for various applications, emphasizing the importance of chromium in achieving the desired stainless properties.