Keywords: Ductile damage – High strain rate – Nonlinear constitutive modelling
Highly space- and time-resolved experimental data are needed for better understanding and further modelling the mechanisms that govern the damage and fracture of metallic materials and structures in a wide range of strain rates and stress triaxiality ratios.
For that purpose, a plate-impact-driven ring expansion test (PIDRET) set-up using a single-stage gas gun, PDV probes and ultra-high-speed cameras, see [1], is adapted to apply a tension-by-expansion loading to notched rings with achievable local strain rates of the order of 10^6 s^{-1}. Completed by (i) quasi-static tension tests carried out using a standard hydraulic machine and (ii) moderately dynamic tension tests using a split Hopkinson tension bar apparatus, the aim is to cover the strain rate range [10^{-3} s^{-1} , 10^6 s^{-1}] and the stress triaxiality range [0.3 , 1]. Results obtained are intended to feed a coupled plasticity-ductile dynamic damage model, such as the GTN one, see [2].
Notch dimensions were designed by finite element analyses using the commercial computation code Abaqus-Exp. The feasibility of the dynamic tension-by-expansion test and the repeatability of the experimental results are investigated considering various metals and alloys.
References
[1] Gant, F., et al. High strain rate responses of some metals and alloys using a plate impact driven ring expansion test (PIDRET). Int. J. Impact Eng., vol. 184, p.104829 (2024)
[2] Tvergaard V., Needleman A., Analysis of the cup-cone fracture in a round tensile bar, Acta metall, 32(32):p.157-169 (1984).
| Subject : | : | oral |
| Topics | : | 4-4 - Testing of materials and structures under extreme conditions or high-strain rate |
| PDF version | : |  PDF version |
