Thin film lubrication and mixed lubrication in nano scale LUO Jianbin State Key Laboratory of Tribology Tsinghua University, Beijing, China Contents l Introduction l Testing technology l Properties of thin film lubrication (TFL) l Failure of fluid films l Lubrication model 4. Plank; 5. Steel ball; 6. Oil cup; 7. Mandril Friction with different substrates Lubrication: paraffin liquid; Load: 2N Effective viscosity with film thickness Effective viscosity v.s. film thickness Concentration of additiv