Cold rolling is made by rolling hot rolled plate as raw material at room temperature and below recrystallization temperature. Cold rolled steel plate is the steel plate produced by cold rolling process, referred to as cold plate. The thickness of cold-rolled plate is generally between 0.1 and 8.0mm, and the thickness of cold-rolled plate produced by most factories is below 4.5mm.

The slight discoloration cold steel coil finishes listed correspond to the center roughness values in the following table and must be tested in accordance with EN 10049.

Surface finish	characteristic	Average surface finish (boundary value: 0,8mm)
Special flat	b	Ra ≤ 0,4 µm
flat	g	Ra ≤ 0,9 µm
Matt	m	0,60 µm ˂ Ra ≤ 1,9 µm
rough	r	Ra ≤ 1,6 µm

The other side slight discoloration cold steel coil must at least meet the requirements of surface type A. The surface finish may be particularly smooth, dull or rough.

The interaction of the allotropes of iron with the alloying elements, primarily carbon, gives steel and cast iron their range of unique properties.

slight discoloration cold steel coil