Smooth clean surface

Within the machine the steel is passed between sets of rotating roller brushes that spin on an axis perpendicular to the sheet's direction of travel.

The roller brush exterior is an engineered abrasive, similar to Scotchbrite, that makes contact with the steel under pressure.

The remaining wüstite layer is only a few micrometres thick and highly polished to a smooth surface.

The SCS process imparts a measure of rust resistance to the sheet steel, so that when exposed to a noncondensing atmosphere, its propensity to rust is markedly less than that of hot rolled steel that is not treated with the SCS process.

The exact metallurgical phenomenon underlying this transformation of the surface to make it more rust resistant is not fully understood; however, it is theorized that the remaining wüstite layer (chemical symbol FeO) contains a much lower proportion of oxygen than the removed hematite and magnetite layers and is, therefore, more stable and less prone to oxidation when exposed to a noncondensing atmosphere.