Atomistic-model informed pressure-sensitive crystal plasticity for crystalline HMX

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:232

Article

Ma, Ran¹  Sun, WaiChing¹  Picu, Catalin R.² 

[1] Columbia Univ, Dept Civil Engn & Engn Mech, 614 SW Mudd,Mail Code 4709, New York, NY 10027 USA

[2] Rensselaer Polytech Inst, Dept Mech Aerosp & Nucl Engn, Troy, NY 12180 USA

关键词: HMX;    Crystal plasticity;    Energetic materials;   

DOI  :  10.1016/j.ijsolstr.2021.111170

来源: Elsevier

【 摘 要 】

ABSTR A C T Cyclotetramethylene-Tetranitramine (HMX) is a secondary explosive used in military and civilian appli-cations. Its plastic deformation is of importance in the initiation of the decomposition reaction, but the details of plasticity are not yet fully understood. It has been recently shown that both the elastic con-stants and the critical resolved shear stress for plastic deformation are pressure sensitive. Since initiation takes place during shock loading, the pressure sensitivity of plasticity is highly relevant. In this work, we examine the pressure-sensitivity of the dynamic mechanical behavior of HMX. To this end, we use an elastic-plastic continuum constitutive model of single crystal HMX in which the anisotropic elastic con-stants and direction-dependent yield stress are rendered pressure-sensitive. The pressure sensitivity is calibrated based on input from molecular models. We observe that accounting for pressure sensitivity changes significantly the profile of the elastic-plastic wave and the wave propagation speed upon impact. The accumulated dissipation profile and the total dissipation also exhibit profound differences between the simulations that take account of the pressure-dependence of the plastic deformation and the pressure independent counterpart. (c) 2021 Elsevier Ltd. All rights reserved.

【 授权许可】

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