ASTM D5179-16 (R2021) pdf free download.Standard Test Method for Measuring Adhesion of Organic Coatings in the Laboratory by Direct Tensile Method.
1.1 This test method covers the laboratory determination of organic coating adhesion to plastic substrates by mounting and removing a metal stud from the surface of the coating and measuring the force required to break the coating/substrate bond with a tensile tester. This test method may also he applied to substrates other than plastic.
1 .2 This test method requires that the metal stud be adhered directly to the surface of a coated, cured panel (Fig. I).
1.3 This test method is used to compare the adhesion of coatings to plastic or other substrates, thus allowing for a quantitative comparison of various coating/substrate combinations in laboratory conditions.
1.4 Other tensile test methods are Test Methods D4541, D7234, D7522, and ISO 4624 (hut are not technically equivalent).
1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.
3. Summary of Test Method
3.1 A metal stud is bonded directly to a coated cured panel. The adhesive is allowed to cure according to manufacturer’s recommendations. The specimen is then subjected to test on a tensile tester equipped with an upper coupling adapter (Fig. 2), and a restraining device (Fig. 3).
3.2 If a coating is to fulfill its function of protecting or decorating a substrate, it must adhere to it for the expected service life. Because the substrate and its surface preparation (or lack of it) has a drastic effect on the adhesion of coatings, a method of evaluating the adhesion of a coating to different substrates or surface treatments, or of different coatings to the same substrate and treatment, is of considerable usefulness in the industry.
4. Significance and Use
4.1 The pull-off strength (commonly referred to as adhesion) of a coating is an important performance property that has been used in specifications. This test method serves as a means for uniformly preparing and testing organic coatings on plastic or other substrates.4 Further information may be found in Appendix XI.ASTM D5179 pdf download.