Determination of Johnson-holmquist constitutive model parameters for fused silica

Abstract

Johnson-Holmquist constitutive model parameters for Fused Silica under dynamic conditions were determined by means of an inverse calibration technique. The identification of the parameters was performed with an multi-object optimizer using experimental data generated by two different validation tests: Taylor Cylinder Impact tests and Drop Weight tests, with impact velocity and strain rate ranging from 1 to 100 m/s and from 102 to 104 s−1, respectively. The validity of the parameters set determined in this way was verified comparing numerical predictions and experimental results for an independent designed test, given by a fused silica tile impacted at prescribed velocity by a steel sphere.