Flexibility describes the ability of a material to change shape under mechanical deformation with no loss of quality.
The flexibility of a coating is therefore key to the enduring functionality of a component or work piece. Because, depending on application, the applied paint films are subjected to various chemical and/or physical stresses during the course of their use, which challenge their flexibility. A distinction is made here between two types: bending elasticity during slow deformation and impact elasticity with fast deformation. Whether or not a coating film satisfies the requirements of flexibility depends on multiple factors. The material characteristics of the binding agent employed plays a role here, alongside the degree of cross-linking, the level of pigmentation, the thickness of the film coating and the adhesion to the substrate.
Various tests are conducted to test the flexibility and elasticity of coatings. Further information on the individual test procedures can be found in DIN 53152 (ISO EN 1519) as well as in DIN 53153 (ISO EN 1520), DIN 55996 and DIN 53154.