Abstract
The purpose of this paper is to clarify the mechanism and lubricating effects of outflow behavior of lubricant trapped in pits by using a rolling-type tribometer and strip-ironing type tribometer. The pits regularly arranged on a workpiece surface were produced by coining a die surface topography. Experiments results show that the lubricant trapped in pits is difficult to enter into contact interface when the seal condition of surrounding the pit is tight. The lubricating improvement effects of pits are largely dependent on the lubricating regime in the blank region and disappear rapidly with the shift of the lubricating regime in the blank region from the boundary lubrication to the hydrodynamic lubrication.
