Abstract:
Surface damage to automotive plastic fasciae is a result of sliding contact scenarios, such as vehicle-to-vehicle contact. This study uses classic analytical methods and finite element analysis to compare subsurface stresses induced by a large curvature counterface on a thin plastic substrate. The work is the first quantitative study of its kind to aid in developing a friction-induced damage (FID) testing device. The authors review relevant analysis methods and present phenomenological insights into FID. They investigate a cylindrical counterface and a painted plastic substrate on a stiff foundation, with a thin polymer coating on the counterface providing a sliding frictional coefficient of approximately 1.0. Three-dimensional numerical analysis results are presented for transverse contact stresses, considering different counterface curvatures, friction coefficients, and normal forces. The study finds that as curvature is reduced, the subsurface maximum stresses move toward the counterface. Numerical calculations suggest that shear initiates subsurface failure in TPO-on-foam substrates. It is concluded that classic Hertzian calculations are inadequate, especially when material yielding and shear failure are present.
