Study on the Contact Characteristics Between Non‐Gaussian Rough Spheres and Rigid Smooth Surfaces Under Mixed Lubrication Conditions

ABSTRACT The ball screw serves as one of the primary transmission modes in the feed system of machine tools, where the contact performance between the roller and the track during operation is a crucial factor influencing machining accuracy. Traditional research has often simplified the contact between two rough surfaces to a rigid plane and a Gaussian‐distributed rough surface; however, it has been observed that the actual surface exhibits non‐Gaussian roughness characteristics. Consequently, this study proposes a mixed lubrication contact model that incorporates non‐Gaussian rough surfaces. This model analyses the effects of surface topography parameters on normal and tangential contact forces, as well as the actual contact area. Additionally, the fluid Reynolds equation for lubrication on non‐Gaussian rough surfaces is established to explore the coupling relationship between fluid parameters and non‐Gaussian surface parameters. Through these analyses, the impact of multi‐factor coupling on the frictional contact performance between rollers and tracks under mixed lubrication conditions is revealed, thereby providing a theoretical foundation for optimising the static and dynamic analysis of precision feed systems in machine tools.