Stainless steel and chromium oxide layer

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Stainless steel features a protective chromium oxide layer that is only 3-4 atoms thick, yet it remains intact despite contact. This layer forms almost instantaneously when chromium reacts with oxygen, with regeneration occurring in nanoseconds after any wear. The rapid formation of this layer is crucial for maintaining the corrosion resistance of stainless steel. Similar protective mechanisms are observed in aluminum, highlighting the importance of oxide layers in metal durability. The quick regeneration of the chromium oxide layer is key to the longevity of stainless steel surfaces.
PatrickP2
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Stainless steel has a protective layer on its surface, which is 3-4 chromium oxide atoms thick. How is it possible that such a thin layer does not rub off immediately when we touch it?
 
Engineering news on Phys.org
It most likely rubs off immediately but it is recreated in a matter of nanoseconds according to this article.

The chromium oxide layer forms on the stainless steel surface when chromium reacts with oxygen. This happens instantly, with formation speeds measured in nanoseconds [...]
 
Aluminum does something similar.
 
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