ADVANCES IN COATINGS TESTING

Accelerated test procedures are largely responsible for improvements in coating performance and durability. Over the years, exposure test cycles have been improved to better approximate a product's end use and service environment. This article describes the work of the American Society for Testing and Materials subcommittee on accelerated tests for protective coatings. Several standards are described, including a new xenon arc exposure specification that simulates the effects of sunlight, moisture and heat on paints. The specification includes a table of exposure cycles for general coatings, exterior pigmented stains, exterior wood stains, and coatings for marine and automotive applications. Another specification effectively blends conventional fluorescent ultraviolet/condensation testing with cyclic corrosion testing. This procedure produces more realistic corrosion on industrial maintenance paints, such as those applied to bridge structures.