ASTM B905-00(2005)

If a coating is to fulfill its function of protecting or imparting unique properties to the surface of a substrate, it must adhere to the substrate for the expected service life. Because surface preparation (or lack of it) has a drastic effect on adhesion of coatings, a test method for evaluating adhesion to different surface treatments or of different coatings to the same treatment is of considerable use to the industry.

The limitations of all adhesion methods, and the specific limitation of this test method to lower levels of adhesion (see 1.3) should be recognized before using it. These test methods are mechanized adaptations of Test Methods D 3359; therefore, the intra- and interlaboratory precision of these test methods are similar to Test Methods D 3359 and to other widely-accepted tests for coated substrates, for example, Test Method D 2370, but this is partly the result of it being insensitive to all but large differences in adhesion. The pass-fail scale of 0 to 5 for Method B1 and B2 was selected deliberately to avoid a false impression of being sensitive.

1.1 These test methods describe procedures for assessing the adhesion of metallic and inorganic coatings and other thin films to metallic and nonmetallic substrates. Assessment is made by applying pressure-sensitive tape to a coated surface and then utilizing a mechanical device to remove the tape at a regulated, uniform rate and constant angle while simultaneously recording the removal force.

1.2 Four methods are described. Methods A1 and A2 are intended primarily for use on parts. Methods B1 and B2 are intended primarily for use in laboratory evaluations. Methods B1 and B2 are not recommended for testing coatings and films on polymer substrates.

1.3 These test methods may be used to establish whether the adhesion of a coating to a substrate is within a required range (between a quantified low and a quantified high level). Determination of actual adhesive forces requires more sophisticated methods of measurement. In multilayer systems adhesion failure may occur between intermediate coating layers so that the adhesion of the total coating system to the substrate may not necessarily be determined.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.