Flow and fracture behavior of high-strength armor steel PROTAC 500

This paper discusses the flow and fracture properties of high-strength armor steel PROTAC 500. Based on combination of both experimental and numerical studies, material parameters for the Johnson-Cook (JC) strength and fracture model were determined. For that purpose, experimental tensile tests were conducted at elevated temperatures (20-400 °C), various strain rates (0.001-1 s−1) and triaxialities of axisymmetric notched specimens (0.333-1.431). Some test specimens were photographed during the testing, and by means of image processing, input data for calculation of true stresses and strains up to the point of fracture were extracted. After determination of strength material parameters, tensile axisymmetric tests with different triaxialities were numerically simulated and triaxiality data from the simulations were taken for evaluation of the material parameters of the damage model. Validation study was also performed successfully. The results of this paper will enable numerical prediction of large deformation processes as well as possible fracture occurrence, its development and final size, for structures made of high strength armor steel, PROTAC 500.