Determination of dynamic plastic deformation behavior of DP 590 steel

Extraction of mechanical properties, including plastic and fracture properties, of sheet metal under quasi-static and dynamic states is one of the fundamental issues in crashworthiness studies. According to standards, samples with various geometries can be employed to extract dynamic and quasi-static mechanical properties. Given the dependence of the yield behavior results and fracture strain on the geometry of the test specimen, it is essential for a specimen used under dynamic conditions to have maximum compatibility with quasi-static uniaxial tension test specimens and to be usable in both conditions. Therefore, in the present study, various geometries were initially designed and evaluated to determine plastic behavior. The effect of geometric parameters on the results of uniaxial tension tests was evaluated, and a suitable specimen for extracting dynamic and quasi-static mechanical properties was presented. Additionally, based on the results of quasi-static and dynamic uniaxial tension tests on the selected specimen at strain rates of 0.01/s to 30/s, the sensitivity of the plastic behavior to strain rate was determined. Furthermore, through the calibration of the coefficients of the Johnson-Cook constitutive model, strain rate-dependent plastic behavior was determined within the desired range and strain rates beyond that.