Unlike traditional steel, stainless steel does not rust or tarnish—hence its name. This property results from the chromium content within the alloy.
To create stainless steel, at least 10.5% chromium is added to an iron alloy. On the surface of the steel, the chromium forms a thin oxide layer (Cr2O3) known as the "passive layer." As a result, the steel is protected from corrosion. Higher corrosion resistance comes from increased chromium content, which prevents rust formation.