A practical constitutive model covering a wide range of strain rates and a large region of strain

Abstract
Through intensive analysis of the tensile stress-strain curves of a variety of materials over a wide range of strain rates of the order of 10 s^-1 obtained systematically by using the Sensing Block Type High Speed Material Testing System (SBTS), two unified sets of values of parameters for a modified constitutive model specified for the materials group, were obtained. The one set is for homogenous deformation and the other is for a wide range of deformation reaching the true fracture strain. It was confirmed that both sets are useful to simulate the dynamic stress-strain curves of any material belonging to the material group of ferrous metals, including the viscous term at high strain rates and the true fracture strain, over the wide strain rate range, as long as the quasistatic tensile stress-strain curve of the material concerned is known in advance.