Friction induced paint damage—A novel method for objective assessment of painted engineering plastics

• Published in: Wear Vol. 203; pp. 350 - 361
• Main Authors: Ramamurthy, A.C., Charest, J.A., Lilly, M.D., Mihora, D.J., Freese, J.W.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-03-1997
• Subjects: Friction induced damage (FID); TPO; TPO; Friction induced damage (FID)
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/S0043-1648(96)07453-4

Engineered injection molded plastics are now common substrates of choice for painted bumper fascias in the automotive industry. A major challenge for painted fascias involves potential warranty costs associated with various tribological scenarios that can result in moderate to severe paint delamination. Preliminary failure analysis performed on field specimens indicate surface damage in majority of cases to be ‘cohesive’, within the surface layers of the substrate. This failure mode is typical of polyolefinic substrates such as impact modified polypropylenes and referred to in this work as friction induced damage (FID).
A specially designed computer controlled laboratory device and an approach to objectively assess FID to painted plastics based on optical observations of test specimens and measurements of total energy consumed during the sliding process are described in this paper. This device simulates FID performance similar to those observed in the field. This work, to our knowledge, is the first of its kind describing FID phenomenon, and its quantitative assessment. Ranking of painted plastics for FID based on this device has aided in the implementation of robust substrate/painted material systems with proven improvement in surface durability.