The performance of coatings when influenced by external stresses caused by stretching, bending or impact, determines their suitability for their designed application. A coating designed for use in the coil coating industry, for example, should have the ability to stretch as the substrate is formed into its desired shape without damage.
Deformation or damage can reduce the protective quality and appearance of the coating including colour change, adhesion, gloss, etc. A coating designed for industrial use should be able to withstand an acceptable level of impact during the life of the product.
In order to characterise a coating’s performance to elongation and deformation, a number of repeatable and reproducible tests have been developed.