New Accelerated Weathering Tests Including Acid Rain

By Magnus Palm, Bo Carlsson

A procedure for the design of reliable accelerated weathering tests for service life prediction of automotive coatings was developed and used in designing an accelerated test based on SAE method J 1960. The influence of exposure conditions was investigated in several accelerated tests.

Results from these tests and from Florida exposures were used to optimize test conditions. A test cycle that includes acid rain spraying was developed and evaluated by exposing 16 different coating systems using various methods. The results indicate that the new cycle is more reliable than a cycle commonly used today.