基于电磁补偿天平的微纳力值标准装置的性能研究

采用基于电磁补偿原理的精密天平，研制了一种微纳力值标准装置。通过高等级的标准砝码对天平进行校准，实现标准装置力值的SI溯源，在500 nN~500μN范围的力值测量标准不确定度小于0.7%。该装置用于对原子力显微镜（AFM）微悬臂弹性常数和微小力值传感器的力值提供准确的溯源。采用多自由度位置调整系统调整被测微悬臂或传感器的位置及俯仰角度，提高了定位准确度。对几种不同弹性常数的AFM微悬臂进行测量，测量结果的标准偏差小于1.6%，满足高准确度微小力值测量的要求。

Investigation on Characteristics of Micro-nanoNewton Force Standard Based on Electromagnetic Compensation Balance

A micro-nanoNewton force standard based on an electromagnetic compensation balance was developed. The standard weights with high grades are used to calibrate the balance. As a result,the realized force of the micro-nanoNewton force standard is traced to the International System of Units(SI). The standard uncertainty of force mea?surement in the range of 500 nN-500μN is better than 0.7%. The force standard is applied to accurate traceability for spring constant of cantilevers in Atomic Force Microscope(AFM)and force of small force transducers. The posi?tion and pitch angel of the cantilevers or transducers to be calibrated are adjusted by a positioning adjustment sys?tem with multi-degree of freedom to improve the accuracy of positioning. Several AFM cantilevers with different spring constants were calibrated using this standard. The standard deviations of the measurement results are better than 1.6%,meet the requirements for high accuracy small force measurement.