Process	Anodizing & Hard-anodizing
	Decorative anodizing is used for corrosion and wear resistance, for achieving a uniform and smooth finishing, for colouring, and for facilitating adhesion of paints and lacquers. Thickness: 5-25 micron. Hard-anodizing is used for technical purposes: against corrosion and wear, for electrical insulation, and, by impregnating the surfaces with teflon particles, for achieving low friction. Thickness: 50-100 micron. The aluminium part is placed in an electrolyte (commonly of sulfuric acid) and used as anode. Due to electrolytic oxidation a protective aluminium oxide layer forms on its surface, which becomes very hard and scratch resistant.
Danish Name	Anodisering & hårdanodisering
Category	Surface treatments, Electroplating
Materials	Substrates: Aluminium Magnesium Aluminium oxide (coating)
Typical products	Piston Window frame panel Zoom lens
References	AHC Oberflächentechnik Arbeitsgemeinschaft der Deutschen Galvanotechnik Dansk Anodisering Industri ApS Galvanisk Kompagni A/S Galvano Wernigerode GmbH
Environmen- tal notes	Anodizing is an environment-friendly process, relatively safe. No extraordinary precautions are needed to ensure worker safety, only a minimum of special protective clothing.
Additional info	For colour anodizing electrolytes contain organic acids, and special aluminium alloys determine the colour. Many colours are available. Hard-anodizing uses the same principle but lower temperatures (0 C) and higher current densities.
Photo	Thomas Nissen (Computer graphics)
Copyright	© 1996-2019 Torben Lenau This page is part of Design inSite Disclaimer