Inox: Stainless Steel Finishes

Providing a range of architectural benefits, this low-maintenance and corrosion-resistant building material produces a multitude of applications from the small kitchen to towering skyscrapers. A powerhouse material on its own with the inert ability to be transformed into different finishes, stainless steel should be included on every architect's go-to building material.

Mill Finishes
Commonly the basic supply, hot or cold-rolled mill finishes are used for standard building components but can also very well cater to the advanced architectural surface requirements. During the hot rolling and annealing process, this stainless steel finish is acid cleaned for the removal of scale and maximum corrosion resistance. Applications would range from non-decorative or functional sheet metal products to plumbing fixtures.

Mechanically Polished and Brushed Finishes
Wet or dry mechanical finishes include using abrasive materials to cut the steel surface. These range from the choices of unidirectional finishes, belt and brush type, and polishing process itself. The wet or oil-faced emery finish is much smoother and expensive than the dry or fiber-brushed surface as it yields a high-luster, low roughness, silk sheen finish. Suitable for use where quality appearance and hygiene is important, it is recommended to be used on commercial kitchens (dishwashers, freezers, work surfaces, sink units) and public places (sanitary facilities, kick-plates).

Patterned Finishes
Patterned-roll finishes are appropriate for the large flat cladding-covered areas such as airport terminals, building entrances and lift cages since reduction of visual surface optical distortion known as oil canning is accentuated. Formulated by pressing or rolling, these patterned finishes stiffen the sheet thinning which leads to economical savings. Also advisable to use in areas wherein public interference and foot traffic are at a high rate, patterned stainless steel surface show less accidental scratches.

Electrolytically Colored and Organic Finishes
The innate chromium oxide providing the corrosion resistance and self-repair when exposed to oxygen also yields color with the chemical and electrolytic processes. While the stainless steel is immersed in an acid solution with a time pressure, surface film is converted through the superimposition of reflected light. This in turn will produce colors ranging from bronze, blue, gold, red, purple and green. For a black film, stainless steel can be dipped in a sodium dichromate. Most suitable for the design details of door framing. Organic coatings, on the other hand, are seam welded with the stainless steel powder at the joinery. The primer coatings of the patterned or polished stainless steel sheets should be applied to the reverse side to equip strong bonding to composite panels.

Specialist Decorative Finishes
An innovative technique would include the acid etching of a stainless steel surface. The process will produce a removal of small amount of surface material which would showcase a dull and coarse look in contrast with the smooth, un-etched and polished satin finished surfaces. Other specialist modern techniques comprise of shot blasting and grinding which makes use of the masking for surface protection. For the creation of graphic designs onto the steel, silk screen and photoresist process transfer pattern onto the surface, then acid etched to emboss the pattern. Typical application would include lifts, doors, escalators, stairs, walkways, building cladding, wall panels, sinks, countertops, bar tops and any surface susceptible to fingerprints.

What other stainless steel finish techniques that you know of? Leave your comments below!