EN 12373-4 Aluminum and Aluminum Alloys - Test for Loss of Absorption Power of Anodic Oxidation Coatings

EUROLAB, with its state-of-the-art accredited laboratories and expert team, offers precise and rapid testing services within the scope of EN 12373-4 testing. This part of this European Standard specifies a method for estimating the loss of absorbency of sealed anodic oxidation coatings by dye absorption after acid pretreatment.

The method is suitable for use as a production control method and can be applied to anodic oxidation coatings that may be exposed to weathering or aggressive environments or where resistance to staining is important.

The method cannot be applied to the following coatings:

• If formed on alloys containing more than 2% copper or more than 4% silicon;
• It is sealed by the dichromate process;
• Those who have undergone additional processing; for example oiling, polishing;
• It is colored in dark tones;
• Having a thickness of less than 3 cl.m.

This method is less suitable where nickel or cobalt salts or organic additives are added to the holding bath.

A degreased area of ​​the sample is subjected to the action of an acid and then the coloration obtained after the application of a dyeing agent is observed.

Absorption power refers to the ability of the anodic oxidation coating to retain dyes during the dyeing process. The test is designed to evaluate the effect of sealing on the absorbent power of the coating.

The standard may specify a procedure for pre-acid treatment before performing the dye spot test. This process step may be related to the evaluation of the properties of the coating.

This standard applies to anodized coatings on aluminum and its alloys and is particularly valid for coatings that have undergone sealing processes. The method is used for quality control and to evaluate the effectiveness of the sealing process.

EUROLAB assists manufacturers with EN 12373-4 test compliance. Our test experts, with their professional working mission and principles, provide you, our manufacturers and suppliers, the best service and controlled testing process in our laboratories. Thanks to these services, businesses receive more effective, high-performance and quality testing services and provide safe, fast and uninterrupted service to their customers.