No, stainless steel is not just iron with a nickel coating. Stainless steel is an alloy, a mixture of iron with specific elements added to enhance its properties. The key ingredient that makes stainless steel "stainless" is chromium, not nickel. Typically, stainless steel contains at least 10.5% chromium by mass, which forms a protective layer of chromium oxide on the surface, preventing rust and corrosion.

Nickel is often added to some stainless steel alloys (like the popular 304 or 316 grades) to improve strength, ductility, and corrosion resistance, especially in harsh environments. However, it’s not a coating—it’s mixed into the alloy during the manufacturing process. Other elements like carbon, molybdenum, or manganese can also be included depending on the type of stainless steel.

So, rather than being a coated product, stainless steel is a homogeneous material engineered for durability and resistance to staining and rust. Coatings can be applied to iron or steel for protection (like galvanizing with zinc), but that’s a different process from what defines stainless steel.