This painless condition occurs when the little bumps on your tongue grow long and trap bacteria that live in your mouth -- making the tongue look black and hairy. Causes can include antibiotic use, poor oral hygiene, smoking, drinking a lot of tea or coffee, and not producing enough saliva.
Hello, Jie. The word passivate is a bit troublesome because aluminum cannot be passivated in the same sense as stainless steel; but it can be passivated in the same sense as zinc plating, i.e., with a chromate conversion coating.
As for the Chromium content, what that does is the coolest part. When Chromium is exposed to oxygen, it creates a thin passivation layer over the stainless steel that is impervious to air and water-preventing the potential corrosion of everything below it. But that isn't where it ends. If the surface is scratched, this layer quickly reforms to recreate that passivation layer.