An analysis of the Tvergaard parameters at low initial stress triaxiality for S235JR steel

Abstract

This paper discusses the influence of the Tvergaard parameters, q_i, which are basic constants of the Gurson-Tvergaard-Needleman (GTN) material model, on the numerically simulated load-carrying capacity of tensile elements made of S235JR steel. The elements were considered to be under static tension at low initial stress triaxiality σ_m/σ_e = 1/3. Two sets of the Tvergaard parameters q_i were analyzed: those typical of structural steels and those dependent on material strength properties. The results showed that the Tvergaard parameters, q_i, had influence on the load-carrying capacity of tensile elements at low initial stress triaxiality. They affected the strength curves and the changes in the void volume fractions determined for S235JR steel elements.