Perforation Test as an Accuracy Evaluation Tool for a Constitutive Model of Austenitic Steel

Abstract

Abstract In this paper, a new method for assessing the accuracy of a constitutive model is proposed. The method uses perforation test done by drop weight tower. The assessment is carried out by comparison of striker velocity curve obtained using experiment and FEM simulation. In order to validate proposed method the various constitutive equations were applied i.e. Johnson-Cook, Zerilli-Armstrong and the extended Rusinek-Klepaczko to model mechanical behaviour of X4CrMnN16-12 austenitic steel. The steel was characterized at wide range of strain and strain rates using servo-hydraulic testing machine and split Hopkinson pressure bar. The relative error calculated as a difference between measured and constitutive model based stress-strain curve was applied as a reference data (classic approach). Subsequently, it was compared with relative error determined on the basis of experimental and FEM calculated striker velocity (new approach). A good correlation between classic and a new method was found. Moreover, a new method of error assessment enables to validate constitutive equation in a wide range of strain rates and temperatures on the basis of a single experiment.