1 Scope
This document specifies the apparatus, the reagents and the procedure to be used in
conducting the neutral salt spray (NSS), acetic acid salt spray (AASS) and copper-accelerated
acetic acid salt spray (CASS) tests for assessment of the corrosion resistance of
metallic materials, with or without permanent or temporary corrosion protection.
It also describes the method employed to evaluate the corrosivity of the test cabinet
environment.
It does not specify the dimensions or types of test specimens, the exposure period to be used for a particular product, or the interpretation of
results. Such details are provided in the appropriate product specifications.
The salt spray tests are particularly useful for detecting discontinuities, such as
pores and other defects, in certain metallic, organic, anodic oxide and conversion
coatings.
The NSS test is particularly applicable to:
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— metals and their alloys;
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— metallic coatings (anodic and cathodic);
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— conversion coatings;
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— anodic oxide coatings;
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— organic coatings on metallic materials.
The AASS test is especially useful for testing decorative coatings of copper + nickel
+ chromium, or nickel + chromium. It has also been found suitable for testing anodic
and organic coatings on aluminium.
The CASS test is useful for testing decorative coatings of copper + nickel + chromium,
or nickel + chromium. It has also been found suitable for testing anodic and organic
coatings on aluminium.
The salt spray methods are all suitable for checking that the quality of a metallic
material, with or without corrosion protection, is maintained. They are not intended
to be used for comparative testing as a means of ranking different materials relative
to each other with respect to corrosion resistance or as means of predicting long-term
corrosion resistance of the tested material.