A silver/white deposit used generally on industrial products for corrosion protection, and in the chemical and food industries to prevent iron contamination. It provides better corrosion and chemical resistance, greater hardness, wear resistance and lubricity than electroplated nickel.
An electrically induced oxidation of the surface of aluminum in an acidic solution. The anodized oxide layer is greatly increased in thickness over that of natural oxidation. By controlling temperature, current, voltage and concentration the thickness of the oxide coating may be accurately controlled to give a high degree of protection against the atmospheric conditions prevailing in our environment.
Technically, passivation is not cleaning but is a process of dipping fittings into a nitric acid solution to rapidly form a chromium oxide on the surface of the material, creating a passive film that protects stainless from further oxidation. The purpose of passivation is to remove both grease left from manufacturing and traces of steel particles that may have rubbed off manufacturing tools onto the fitting.