This Standard describes methods for checking the adhesion of electrodeposited and chemically deposited coatings. It is limited to tests of a qualitative nature. Table 1 indicates the suitability of each test for some of the common types of metallic coatings. Most of the tests described are capable of destroying both the coating and the article being tested, but some destroy the coating only. Even if the adhesion of the coating is found to be satisfactory on articles not destroyed in testing, it should not be assumed that the articles are undamaged. For example, the burnishing test (see Clause 3.1) may render an article unacceptable and the thermal shock test (see Clause 3.12) may produce unacceptable metallurgical changes.

This Standard does not describe tests that have been developed to give a quantitative measure of adhesion of metallic coating to a substrate, since such tests require special apparatus and considerable skill in their performance which renders them unsuitable as quality tests for production parts. Some of these quantitative tests may, however, be useful in research and development work.

NOTES:

1 When particular methods of adhesion testing are included in Standards for individual coatings, they should be used in preference to the methods described in this Standard and should be agreed upon beforehand by the supplier and the purchaser.

2 The test procedures described in this Standard do not necessarily include all of the precautions required to satisfy health and safety aspects. Care should be taken to ensure that the procedures are carried out only by people who have received suitable training. Guidance in the handling and use of hazardous chemicals is given in AS/NZS 2243.1 and AS/NZS 2243.2.

3 Base metal variations of yield and hardness may cause misinterpretations in the test results.