Refining the friction force through periodically grooved surfaces

Abstract

Preparing textured surfaces is an effective method for regulating friction; however, the influence of surface geometry on friction remains ambiguous. In this study, we measure the friction force on silicon samples with various periodic grooves using atomic force microscopy. Our findings indicate that the friction increases with groove width under a fixed groove coverage ratio of 50%. This observation is further corroborated by molecular dynamics simulations. Additionally, it has been demonstrated that increasing the groove width while maintaining a constant periodic length results in enhanced friction due to an elevated energy barrier. Conversely, extending the periodic length while keeping the groove width fixed leads to a reduction in friction, attributed to a longer dissipation distance for accumulated energy. Our study illustrates that the energy barrier and dissipation distance can be affected by surface geometry, which are crucial factors in determining the friction of textured surfaces.