ASTM D7093-13 Formability of thin-film organic coatings on Steel

Scope:

The formability and adhesion of thin-film organic coatings applied over steel are determined using the ASTM D7093-13 standard test method. Coatings with a thickness of 2.5 to 10 microns are usually analyzed using this method. ASTM D7093-13 can be utilized for the determination or control of the manufacturing process. The method is useful for studying coating performance and developments required in coatings to improve the product. 

Test procedure:

The coated specimen is stretched biaxially in a machine to a given distance. The adhesion rating of the coating is determined by applying adhesive tape over the deformed area (dome). The tape is pulled off and the amount of coating removed is compared with a standard photograph.

Specimen size:

The specimen can be square or rectangular but not narrower than 90 mm (3.5 inches) in either dimension.

Data: 

A rating from 10 ( good, no removal) to 0 (poor, complete removal) is used (Figure 1) to visually rate the adhesion of the coating after forming and tape removal using the photographic standard.

Figure 1: Photographic standard adhesion rating