Influence of Microstructural Anisotropy on the Spallation of 1080 Eutectoid Steel

Abstract

While the influence of crystallographic texture on elastic and plastic constitutive response has seen extensive investigation in recent years, the influence of texture on the dynamic fracture of engineering materials remains less extensively explored. In particular, the influence of anisotropy, both textural and morphological, on the spallation behavior of materials remains poorly quantified. In this study, the spallation response of 1080-steel has been studied as a function of microstructural morphological anisotropy. In this study the influence of elongated MnS stringers, resident within a crystallographically isotropic eutectoid steel, on the spallation response of 1080 steel was investigated. That of a fully-pearlitic 1080 steel loaded to 5 GPa was found to be dominated by the heterogeneous nucleation of damage normal and orthogonal to the MnS stringers. Delamination between the matrix pearlitic microstructure and the MnS stringers was seen to correlate to a significantly lower pull-back signal during transverse loading than to that parallel to the stringer axis. The "pull-back" signals and postspallation metallographic observations are discussed with reference to the influence of microstructural anisotropy on void nucleation and growth.

Constitutive behaviour of anisotropic materials under shock loading

“…Gray et al, 2000Gray et al, , 2002Vignjevic et al, 2002). It was shown in an investigation of cold rolled and annealed zirconium (see Gray et al, 2000) that the value of stresses varies in different directions in the quasi-static test and plate impact test.…”

Frontiers in Anisotropic Shock-Wave Modeling

“…It was shown in an investigation of cold rolled and annealed zirconium (see Gray III et al [25]) that the value of stresses varies in different directions in the quasi-static test and plate impact test. Gray III et al (26) showed that under shock loading conditions (one-dimensional strain space), the variation of the Hugoniot elastic limit (HEL) or the yield strength of annealed zirconium was consistent with the quasi-static experimental data. Previously, Butcher (20) worked on aluminum alloy 6061-T6 and predicted that spall strength should vary in accordance with the one-dimensional yield strength depending on material orientation.…”

“…Also, Gupta (74) presented experimental data for shock propagation along the 111 crystallographic direction in single-crystal LiF, with the observed elastic response up to 30 kbar experimental bounds and including shock propagation data along the 100 , 110 , and 111 directions (Gupta [75]). The dynamic elevated-temperature elastic properties of single-crystals and polycrystalline aluminum were studied by employing a laser pulse technique to produce propagating stress pulses in slender rods (Swearengen et al [76] For many years, it has been assumed in the shock-wave community that the response of materials to high intensity shock loading is isotropic, and only recently has anisotropy in the shock response attracted the attention of researchers (e.g., Gupta [75], Dick and Ritchie [78], Gray III et al [25,26]). It was shown in an investigation of cold rolled and annealed zirconium (see Gray III et al [25]) that the value of stresses varies in different directions in the quasi-static test and plate impact test.…”

“…The impact loading of anisotropic materials is a subject that has received considerable attention for both low and high velocity in the recent monographs on composite materials (e.g., Abrate [8], Reid and Zhou [9], Ryan et al [10]) and in recent research papers on composite materials (e.g., Hereil et al [11], Bordzilovsky et al [12], Dandekar et al [13], Espinosa et al [14], Millett et al [15], Aktaş et al [16], Hazell and Appleby-Thomas [17], García-Castillo et al [18], Tekalur et al [19]), research papers on metals (e.g., Butcher [20], Johnson and Barker [21], Stevens and Tuler [22], Rosenberg et al [23,24], Gray III et al [25,26], Rubin [27]), and research papers on single crystals (e.g., Winey and Gupta [28][29][30]). …”

Anisotropic constitutive model and numerical simulations for crystalline energetic material under shock loading

“…Winey et al [19] and Winey and Gupta [20, 21] incorporated nonlinear elasticity and crystal plasticity in a thermodynamically consistent tensor formulation for problems involving shock waves in copper and LiF single crystals. Modeling efforts to extend crystal plastic anisotropy under quasi-static loading to simulations under shock loading for more widely-used materials have also been made [22, 23]. Lattice rotation, which is of significant for low-symmetric shocked single crystals, should not be neglected in such models.…”