Surface finish on stainless steel has an important effect on its corrosion resistance and the mere specification of 316 type stainless steel for exterior architectural applications is not in itself sufficient. Coarse polished finishes will exhibit deep grooves where chloride ions can accumulate and destroy the passive layer, thereby initiating corrosion attack.
It is therefore important that in coastal/marine situations where a ‘satin’ polished finish is required that the specification should include a maximum traverse surface requirement of 0.5 microns Ra. A simple description such as ‘satin’ or ‘brushed’ would be insufficient to guarantee a smooth polished finish with good corrosion resistance.
Stainless Design’s balustrade products are offered in the following finishes:
Brushed finish alternatives are often promoted as the costs involved in attaining a perfect mirror finish are considerably higher.
Stainless Design utilizes automated surface finishing techniques that ensure product of consistent quality and allow us to attain a mirror finish efficiently and cost effectively. Your balustrading will look better for longer and require less maintenance. In mirror installation grade 316 L (marine grade) stainless steel is used.
Satin finishes are generally used indoors and in non-corrosive environments where high corrosion resistance is not required. The benefit of a satin finish in these applications is that they do not show touch marks as readily as the mirror product and consequently will not require as much superficial cleaning. If a very fine satin finish is used this can result in the surface discoloring when touched. We therefore recommend a sanding coarseness of no finer than 400 grit. In satin finish installations grade 304 stainless steel is used.