Stone-impact damage of automotive coatings: A laboratory single-impact tester

摘要

Coating damage due to stone impact remains one of the major concerns of the automotive industry. The development of new environmental-friendly paint systems prompts the paint manufacturers to pay more attention to the issue of reliable test methods that also approximate actual service conditions. This paper describes a single-stone impact tester developed at Delft University of Technology. The apparatus uses compressed air to launch a shaped projectile into a painted specimen. It allows to vary the velocity of the projectile, the angle of impact incidence and the testing temperature over wide ranges. The single impact test technique (methodology) is successfully applied to a set of automotive coating systems designed on water-base technology resulting in good reproducibility. Results are presented of a preliminary study on the influence of the primer crosslinker content on the stone impact resistance of the paint system. (C) 2006 Elsevier B.V. All rights reserved.