ÖNORM EN 12373-6

This Part of this European Standard specifies a method of assessing the quality of sealed anodic oxidation coatings on duminium and its alloys by measurement of the loss of mass &er immersion in phosphonc acid/chromic acid solution without prior acid treatment. A related standard (EN 123 73-7)" describes the Same method used with prior acid treatment. The method is applicable to anodic oxidation coatings intended for decorative or protective purposes or where resistance to staining is irnportant. The method is not applicable to: - hard-type anodic oxidation coatings which norrnally are not sealed; - anodic oxidation coatings that have been sealed only in dichromate solutions; - anodic oxidation coatings produced in chrornic acid solutions; - anodic oxidation coatings that have undergone a treatment to render them hydrophobic. The method is destructive and can serve as a reference method in case of doubt or dispute regarding the results of the test for loss of absorptive power (EN l2373-4)), or the measurement of admittance (EN 1 23 73 -5) ".