Measurement of the intrinsic sensitivity for a single-ended accelerometer without the influence of the mounting condition

The calibration technique for accelerometers has been internationally developed for up to 20 kHz to ensure the reliability of vibration measurement. However, it has been established that the calibrated sensitivity changes at over 10 kHz depending on the mounting conditions, and this makes it difficult to accurately measure the characteristics of accelerometers and degrades the accuracy of high-frequency vibration measurements. Thus, in this study, we developed a reversed-calibration method for measuring the intrinsic sensitivity of an accelerometer without the influence of the mounting conditions. The method was demonstrated experimentally using two reversed-calibration jigs made of ceramic and titanium. As a result, the resonance frequency of the accelerometer was determined consistently to be 46.0(1) kHz (ceramic) and 45.8(4) kHz (titanium), which conforms that the measurement result is intrinsic to the accelerometer. The expanded uncertainty of the calibration was roughly evaluated to be 4.4 % at 20 kHz. Furthermore, the result was independently confirmed by fitting the conventional adapter-calibration results up to 100~kHz with four different materials based on the dynamic three-body model. Concurrently, the material dependency observed during adapter calibration was quantitatively analyzed, after which its relationship with the Young's modulus was extracted. Overall, these results deepen our understanding of the performance of the accelerometer at above 10 kHz, which is essential in vibration metrology and accelerometer development.