Experimental Study and Constitutive Model for the Dynamic Mechanical Properties of Ballistic Gelatine

doi:10.12382/bgxb.2022.0449

Abstract

Abstract: Ballistic gelatine is widely employed as a soft tissue simulant in biomedical applications and terminal ballistics. The accurate measurement of the dynamic mechanical properties of ballistic gelatine has been a topic of great interest in wound ballistics. To solve the problems of weak transmission signal and non-uniform deformation of gelatine materials during dynamic testing, the Hopkinson pressure bar device is equipped with aluminum alloy pressure bars and semiconductor strain gauges, and the pulse shaping technology and slice specimens are adopted. Dynamic mechanical properties tests for 10% and 20% ballistic gelatine at 4℃ are conducted. The results show that the mechanical response of gelatine is nonlinear, and the stress-strain curve consists of an elastic stage and three plastic strengthening stages. The stress dynamic increase factor is linearly related to the logarithm of the normalized strain rate. A polynomial constitutive model that takes into account the strain rate effect can well describe the mechanical behaviours of gelatine at a high strain rate. The research results can provide support for the numerical simulation of small-arms projectiles penetrating gelatine targets.

Key words: ballisticgelatine, lowimpedancematerials, SHPB, dynamicmechanicalproperties, constitutivemodel

CLC Number:

TB302

JIANG Mingfei, XU Hui, HUANG Chenlei, LIU Kun, WU Zhilin. Experimental Study and Constitutive Model for the Dynamic Mechanical Properties of Ballistic Gelatine[J]. Acta Armamentarii, 2022, 43(9): 2113-2120.

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