Abstract: The negative pressures in oil films and their limit values are first relatively accurately measured with a special device in this paper. An unsettled problem having been disputed for many years in studying the surface topography effects in lubrication is solved, so that an important mechanism for load carrying of oil film between two rough surfaces is brought to light. An experimental basis is provided for the further study of surface topography effects in lubrication.

Key words: 极限负压, 气穴, 油膜承载机理, 油膜负压