Formation mechanism and prediction modeling of milled surface topography accompanied with its influence on friction and wear behavior: a review

Milled surface topography significantly influences the tribological performance of machined components by governing contact mechanics, friction, and wear during service. However, investigations into surface topography formation and tribological behavior are often conducted separately, limiting the establishment of a unified link between milling process parameters and functional performance. This review presents a process-topography-tribology framework and examines the formation mechanisms, modeling and simulation approaches, and tribological responses of milled surface topographies. Formation mechanisms are first reviewed, including kinematic-geometric effects, material removal and deformation, and dynamic responses of the machine-tool-workpiece system. Existing modeling and simulation methods for surface topography prediction are then summarized and classified, with their advantages and limitations discussed. Surface topography characterization methods and parameter systems relevant to tribological analysis are also addressed, encompassing height, spatial, directional, functional, and multi-scale parameters essential for correlating surface features with friction and wear. The effects of milled surface topography on friction, wear, and fretting behavior are subsequently analyzed. Tribological responses are shown to depend strongly on surface feature scale, anisotropy, and load-bearing characteristics. Current challenges and future research directions are finally identified, with emphasis on performance-oriented surface topography design, integration of surface prediction and tribological models, and application of digital manufacturing technologies. This review aims to offer a unified perspective connecting milling process design to tribological performance, thereby providing guidance for future research and engineering applications.