FORCE CALIBRATION OF NANO UNIVERSAL TESTING MACHINE USING MILLIGRAM WEIGHTS

This paper presents an approach for calibrating the force transducer on the nano universal testing machine using milligram weights. Previous research on force calibration of such a system focused on the range from 10 mN to 200 mN, ignoring forces below 10 mN. The main purpose of this study is to analyze and calculate the uncertainty of force measurements within the range from 0.2 mN to 10 mN. The ABA calibration method in accordance with OIML R111-1 is adopted to determine the uncertainty in force measurement. The results indicate that the maximum relative uncertainty of force measurement is 7.0 × 10−3 with a 95% confidence level. The investigation can be used as the basis for evaluating measurement uncertainty of the system in small force range.