A critical assessment of surface texturing for friction and wear improvement

Surface texturing to control friction and wear has been the focus of numerous studies in the last few decades. Despite this interest, understanding the underlying causes for surface texturing effects under different contact and lubrication conditions remains a subject of continuing controversy. Although there has been progress in the fabrication of precise surface textures and modeling of their influence in specific cases, many conflicting reports still exist concerning the effectiveness of surface texturing under certain contact conditions. This review therefore presents a critical assessment of the common understanding in this rapidly developing research field. First, the effects of surface textures undet the operative lubrication regimes in the Stribeck curve, with a clear distinction between conformal- and non-conformal contacts, will be discussed. Finally, the strengths and weaknesses of various fabrication methods will be described, giving a summary of the fabrication methods with respect to their typical feature sizes, costs, and applicable materials. Special attention will be paid to the friction reducing mechanisms and their implications for the wear under different frictional regimes. (C) 2016 Elsevier B.V. All rights reserved.