Frictional anisotropy under boundary lubrication: Effect of surface texture

摘要: The friction coefficient was measured under boundary lubrication with a ball-on-flat contact configuration in unidirectional sliding. ball smooth and hardened 52100 steel. Discs were made from case-carburized 4620, annealed 1080, 1018 steels directionally ground surfaces. A synthetic lubricant of stock polyalphaolefin used for testing. During testing each material, frictional spike observed whenever the slid parallel to grinding ridge on disc surface. average all tests about 0.1, which is typical regime. magnitude spikes, reached as high 0.25, their persistence depended hardness On basis elastohydrodynamic theory, coupled observation severe plastic deformation ridges sliding direction, could be due localized surface at locations minimal thickness fluid film. This hypothesis further supported by lack spikes using discs coated thin film diamond-like carbon, minimal.