Do you know many types of surface finishesare available on stainless steels?

Surface Finish Code

Description

Mill finishes

1D

Hot rolled, heat treated, pickled. The most common hot rolled finish. A non reflective, rough surface. Not normally used for decorative applications

2B

Cold rolled, heat treated, pickled, pinch passed. The most common cold rolled mill finish. Dull grey slightly reflective finish. Can be used in this condition or frequently is the starting point for a wide range of polished finishes.

2D

Cold rolled, heat treated, pickled.

2H

Work hardened by rolling to give enhanced strength level. Various ranges of tensile or 0.2% proof strength are given in EN 10088-2 up to 1300 MPa and 1100 MPa respectively dependent on grade

2Q

Cold rolled hardened and tempered. Applies to martensitic steels which respond to this kind of heat treatment.

2R

Cold rolled and bright annealed, still commonly known as BA. A bright reflective finish. Can be used in this condition or as the starting point for polishing or other surface treatment processes e.g. colouring

In the following codes “1” refers to hot rolled being the starting point and “2” as cold rolled

Special Finishes

1G or 2G

Ground. Relatively coarse surface. Unidirectional. Grade of polishing grit or surface roughness can be specified

1J or 2J

Brushed or dull polished. Smoother than 1G/2G. Grade of polishing grit or surface roughness can be specified

1K or 2K

Satin polish. Similar to 1J/2J but with maximum specified Ra value of 0.5 micron. Usually achieved with SiC polishing belts. Alumina belts are strongly discouraged for this finish as this will have detrimental effect on corrosion resistance. Recommended for external architectural and coastal environments where bright polish (1P/2P) is not acceptable.

1P/2P

Bright polished. Non-directional, reflective. Can specify maximum surface roughness. The best surface for corrosion resistance.

2L

Coloured by chemical process to thicken the passive layer and produce interference colours. A wide range of colours is possible.

1M/2M

Patterned. One surface flat.

1S/2S

Surface coated e.g. with tin = Terne coating

2W

Corrugated. Similar to patterned but both surfaces are affected

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