In the late 1970s, scientists at British Steel found that dull polished surfaces on stainless steel showed a wide range of surface roughness. Further tests showed that steels with high surface roughness were severely damaged during polishing operations, while those with a rough surface were relatively unscathed.
In the mid-1980s, dull polished finishes were widely used for projects such as high-profile architectural projects. However, it soon became apparent that some of these dull polished finishes had poor corrosion resistance, particularly when exposed to seawater. As a result, a new description of surface finishing was introduced, which is still in use today.
The three more common options for stainless steel finishing are:
No. 2B is a mill finish, which means that it has not been further worked. Matt finishes have a dull appearance and are not suitable for atheistic end uses. However, they are a good choice when appearance is not important or when further finishing is intended. These are the cheapest of the stainless steel finishes.
Finishes are produced from “cold rolled” stainless steel by means of special rolls or dies. Cold rolling produces a smoother, less pitting surface. Next, it is softened and descaled in an acid solution. The steel undergoes a final pass on polishing rolls to further improve its smoothness.
Common applications include: