The deterministic nature of the fracture location in the dynamic tensile testing of steel sheets

Abstract

The deterministic nature of the fracture location in the dynamic tensile testing of steel sheets

Non-uniform distributions of initial porosity in metallic materials affect the growth rate of necking instabilities in flat tensile samples subjected to dynamic loading

“…We conducted numerical simulations for various impact velocities between 8 m/s and 25 m/s, which correspond to strain rates between 200 and 625 s −1 . This range of velocities, and strain rates, is typically attained in dynamic tension tests performed in fast servo-hydraulic machines [25]. Note that for this range of velocities, and for this specimen size, inertial effects are less important than in the other types of uniaxial tenstion tests like the rapid expansion of rings, where the applied velocities can reach 200 m/s, and the strain rates…”

“…Nevertheless, to the authors' knowledge, most of the attempts carried out so far to simulate numerically the tensile behaviour of flat samples subjected to dynamic loading predict that, contrary to the experimental observations, the growth rate of the pair of necking bands which form the localization process is largely similar [11,16,15,9,25]. It seems that, if the material is isotropic and homogeneous, and the boundary conditions ensure that the stress state in the sample is uniaxial until localization starts, there is not a perturbation in the numerical model that could lead to the asymmetric growth of the two bands.…”

Effect of size on necking of dynamically loaded notched bars

“…The necking behavior under dynamic loading conditions, e.g. Needleman (1991); Knoche and Needlem (1993); Fressenges and Molinari (1994); Guduru and Freund (2002); Mercier and Molinari (2003); Rusinek et al (2005); Osovski et al (2013);Vaz-Romero et al (2015); Rotbaum et al (2015), can be quite different than under quasi-static conditions. Material inertia tends to slow neck development, Needleman (1991); Xue et al (2008); multiple necking can occur, e.g.…”

Local behavior of an AISI 304 stainless steel submitted to in situ biaxial loading in SEM

“…Numerous experimental means and techniques have therefore been adapted from macroscopic to nanometric scale. This allows to study the influence of environmental constraints such as mechanical loading [1,2], temperature [3,4], speed [5,6] or even irradiation [7,8] on the material behavior at a small scale [9]. Numerous studies can be found in the literature regarding the microstructural evolution of materials under in situ uniaxial tensile tests [10,11].…”