摘要
Partial lubrication or mixed lubrication in the nano-scale is discussed, which is consti-tuted from dry contact, boundary lubrication, thin film lubrication. A dynamic contact ratio has beenused to describe such lubrication, and the relationship between the contact ratio and its influencefactors was investigated. Experimental results indicate that the dynamic contact ratio increaseswith the decrease of film thickness by the exponential function. The decrease of speed and lubri-cant viscosity, and the increase of loads will enlarge the value of the contact ratio. When the polaradditives are added into the basic oil, the contact ratio decreases. In addition, the contact ratio ofthe surfaces with small roughness is larger than that of the surfaces with large roughness at verylow speed. However, the contact ratio of smooth surfaces decreases more quickly with speed thanthat of rough surfaces, and therefore, it will become smaller than that of rough surfaces after speedincreases over a certain degree.
Partial lubrication or mixed lubrication in the nano-scale is discussed, which is consti- tuted from dry contact, boundary lubrication, thin film lubrication. A dynamic contact ratio has been used to describe such lubrication, and the relationship between the contact ratio and its influence factors was investigated. Experimental results indicate that the dynamic contact ratio increases with the decrease of film thickness by the exponential function. The decrease of speed and lubri- cant viscosity, and the increase of loads will enlarge the value of the contact ratio. When the polar additives are added into the basic oil, the contact ratio decreases. In addition, the contact ratio of the surfaces with small roughness is larger than that of the surfaces with large roughness at very low speed. However, the contact ratio of smooth surfaces decreases more quickly with speed than that of rough surfaces, and therefore, it will become smaller than that of rough surfaces after speed increases over a certain degree.
