self-passivating alloysReading time:
When elements such as chromium, nickel, molybdenum or copper are included in a ferrous alloy, the resulting alloy can be made self-passivating. These alloys are commonly known as "stainless steels". If they look like bare metals, these alloys do produce a thin layer of oxide on their surface and this layer creates passivation. The components forming this layer are the product of the alloy’s initial corrosion, characterised by a chromium-iron oxide with a spinel structure, see stainless steel.