Brushed steel or brushed metal refers to a surface finish that has an intentionally scratched look. Small unidirectional scratches run across the metal surface causing the metal's reflection to stretch or blur in the same direction, an effect known as anisotropic reflection. Metallic luster is diminished, but not lost completely. Anisotropic materials exhibit unequal physical properties along different axes.
For example, wood is a naturally anisotropic material. Wood grain is the manifestation of the direction, texture, or pattern of fibers found in wood and contributes to its distinct look. The strength and hardness of wood depends on the orientation in which it is being measured. Wood is stronger with the grain.
The opposite of anisotropic materials are isotropic materials. Their physical properties behave the same way in all directions. Most metals, like steel and aluminum, are isotropic materials. When rubbed with an abrasive material, metal takes on anisotropic properties. The look of brushed steel can be achieved by polishing metal with either fine grit sandpaper, sanding discs, Scotch-Brite® pads, Scotch-Brite® wheels, flap wheels, Cratex® wheels, or synthetic steel wool, to name a few. Each method produces a different look and should be experimented with before committing to one.
Patinas can be added to give the metal an aged look, simulating antiquity. Patinas are administered by exposing the metal to chloride or sulfur compounds.
After being polished, the metal should be cleaned of polishing residue with mineral spirits. Mineral spirits, a distillate of petroleum, is a fast-acting, odorless solvent that removes oily residues and prepares the metal for oil-based finishes. Leaving thumbprints at this stage is not advised.
In order to complete the brushed steel look, acrylic urethane can be applied as a coating. This clear coating fills in the etched grooves left by the polishing. It leaves the surface smooth and also protects it from further random abrasion, which might distort or dull the desired effect of anisotropic reflection. Clear lacquer, wax, or satin are also acceptable coating materials.
Many consumer products are made from stainless steel, aluminum, or nickel. These are also the metals commonly used for brushing. As such, table lamps, kitchen cookware, and high-end electronics can be given brushed metal finishes to add a touch of class and enhance their decorative appeal. The brushed steel finish of consumer items is usually highlighted in catalogs as a sell point and is trumpeted as an expression of bold, contemporary style. Of course, beauty ultimately lies in the eye of the beholder.