Friction Induced Paint Damage: The Role of Coating Attributes

The recent inclusion of painted plastic fascias/bumpers into automotive applications has necessitated the evaluation of potential in-service damagability. One failure mode that has been identified, that of friction-induced paint/substrate damage, has been simulated in a laboratory environment. Our goal was to evaluate the effects of coating attributes, both thermal and mechanical, on subsequent performance of painted thermoplastic olefin (TPO) materials. It was determined that the most significant parameters in the paint which contributed to damage were the glass transition temperature, the secant modulus at break, and the static coefficient of friction. This paper will discuss techniques and results used to reach these findings.