Development of Universal Rate Range Load-Cell

Abstract

　　　The purpose of this study is to develop a universal rate range load-cell (URR load-cell) that can measure the compressive properties of large deformation at wide strain rate range. In the previous studies of other researchers, the impact test methods with reduction technique of reflected stress wave have been proposed for the large deformable cellular materials. However, stress wave propagation behavior in load-cells has not been analyzed in detail. In addition, it has been known that the disturbance of stress wave occurred due to the characteristic vibration of the load-cell. First, we investigated the propagation of the stress wave behavior inside the load-cell by finite element analysis. The result showed that responsiveness could be improved by shortening the length of stress detection part. Second, in order to suppress the characteristic vibration, the optimal URR load-cell shape was investigated. It was revealed that reducing characteristic frequency was effective for suppressing vibration. We confirmed that URR load-cell could measure applied load for a longer time than the split Hopkinson pressure bar method.