New Measuring System of Impact Force : Development and Application to the High Speed Blanking Test

Abstract

The impact force is measured usually with the split-Hopkinson-bar method. However, in this method, the measuring time is restricted by the length of the bar. Therefore, one of the authors suggested formerly a new measuring method of the impact force based on the theory of propagation of longitudinal elastic stress wave. In this method, the impact force acting on the end of the bar can be estimated from the measured stresses at two suitable points on the bar, and without any restriction of its time range. We designed and completed a new measuring system based on this method. Using this system, we measured the blanking force in the high speed blanking test. As the result of the test, we confirmed that the measuring system is considerably effective for the purpose.