DIN EN ISO 2106:2011-06

This standard specifies a gravimetric method for determining the mass per unit area (surface density) of anodic oxidation coatings on aluminium and its alloys. The method is applicable to all oxidation coatings formed by anodizing aluminium and its alloys, which are either cast or wrought. It is suitable for most aluminium alloys except those in which the copper content is greater than 6 %. The method is based on the following principle: The anodic oxidation coating on a weighed test piece of known surface area is dissolved, without significantly attacking the basis metal, using a mixture of phosphoric acid and chromium (VI) of specific concentration. After dissolution of the coating, the test piece is reweighed, and the loss in mass is calculated. The mass loss is related to the unit area covered by the coating, and is expressed in milligrams of coating per square decimetre of surface. This test is destructive. The International/European Standard has been prepared under the leadership of ISO/TC 79/SC 2/WG 15 "Anodic oxidation coatings on aluminium" (secretariat: JISC, Japan) in a parallel procedure with CEN/TC 132/WG 15 "Aluminium anodisation" (secretariat: BSI, United Kingdom). On the national level the responsible Working Committee is NA 066-01-09 AA "Anodisch oxidiertes Aluminium" ("Aluminium anodisation") of FNNE.