Measurement of Temperature Dependence of Lubricant Viscosity in Nano Gaps by Fiber Wobbling Method Combined With Laser Heating

In order to ensure the performance and durability of highly accurate mechanical systems, it is urgent to establish lubrication technology realized in minute gaps. It has been reported that the mechanical properties of lubricating oil in minute gaps narrowed down to nanometer order are completely different from those in the bulk state, and measurement of these phenomena are indispensable for lubrication design. In this research, in order to elucidate the temperature dependency of lubricant viscosity in nano gaps, we proposed laser heating of lubricating oil in highly sensitive viscosity measurement method developed in our previous study, which we called the fiber wobbling method (FWM). We succeeded in measuring temperature dependence of lubricating oil viscosity in nano gaps.