Wash Coat - A very thin paint film applied to the backside of a pre-painted sheet specified to have one finished side. The wash coat provides protection in coiling, storage, fabricating and handling.

Water Hardening - High carbon grades of tool steel, straight carbon steels and low alloy steels that are hardened by quenching in water during the heat-treating operation.

Weathering Steel - Steel using alloying elements such as copper, chromium, silicon and nickel to enhance resistance to atmospheric corrosion.  (USS COR-TEN®)

Wet Film Thickness - The thickness of the paint film immediately after coating and prior to curing. The required wet film thickness is dependent on the proportion of solids and solvents in the liquid paint for producing the appropriate dry film thickness.

Work Hardening - An increase in hardness and strength caused by plastic deformation at temperatures lower than the re-crystallization range.