For ferritic chromium steel, its thickness of layer is greater than that of austenite chromium steel.

铁素体型钢的渗层厚度明显大于奥氏体型钢。

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Stick the part in acid, run an electric current through it and we can increase the thickness of the layer by a factor of 20-40.

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Once the container is spinning at the correct speed (typically a few revolutions per minute), the mercury spreads out to form a layer less than a millimetre thick, and in such a way that variations in the thickness of the mercury layer compensate for the imperfect shape of the container.

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When the thickness of the polymer layer was greater than 50 nm, essentially almost all the bacteria were killed.

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