Stainless steel resists rusting primarily due to its chromium content. Here's how it works:

1. Chromium Oxide Layer: Stainless steel contains at least 10.5% chromium, which reacts with oxygen in the air to form a thin, invisible layer of chromium oxide on the surface of the steel. This layer acts as a protective barrier, preventing oxygen and moisture from reaching the underlying iron, which would otherwise react to form rust.

2. Self-Healing: If the stainless steel surface is scratched or damaged, the chromium in the steel will react with oxygen to quickly reform the protective chromium oxide layer. This self-healing ability is a key factor in the corrosion resistance of stainless steel.

3. Other Alloying Elements: In addition to chromium, stainless steel often contains other elements like nickel and molybdenum, which further enhance its resistance to rust and corrosion. For example, molybdenum increases resistance to chloride-induced corrosion, making certain grades of stainless steel suitable for marine environments.

4. Low Carbon Content: Stainless steel typically has a low carbon content, which reduces the risk of corrosion that can be caused by carbon impurities.

These properties make stainless steel highly resistant to rust and suitable for use in a wide range of environments, from household kitchens to industrial and marine applications