Analytical and experimental studies on the strain rate effects in penetration of 10wt % ballistic gelatin

International Symposium on Dynamic Deformation and Fracture of Advanced Materials 2013

物理学;材料科学

Liu, L.^1 ; Jia, Z.^1 ; Ma, X.L.^1 ; Fan, Y.R.^1

State Key Lab of Fluid Power Transmission and Control, Zhejiang University, Hangzhou, 310027, China^1

关键词: High-speed penetration;    Linear relationships;    Mechanical response;    Mooney-Rivlin model;    Penetration problems;    Split Hopkinson pressure bars;    Super elastic behavior;    Uni-axial compression;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/451/1/012035/pdf
DOI  :  10.1088/1742-6596/451/1/012035

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

This work concentrates on modeling the super-elastic behavior of 10wt% ballistic gelatin at 4°C and the mechanical responses at quasi-static and high-speed penetrations. Uniaxial compression and simple shearing experiments were carried out to determine the moduli in Mooney-Rivlin model describing the elastic behavior of gelatin at low strain rates. The failure mode is determined to be elastic fracture as the tensile stretch ratio exceeds a critical value. For high compression strain rates, the available results from the split Hopkinson pressure bar (SHPB) experiments for 10wt% gelatin were carefully examined and assessed. Linear relationship between the moduli and the strain rate is established. Based on these material parameters, an analytic solution of stress for the quasi-static and quasi-dynamic expansion of spherical cavity in gelatin is derived. As a consequence, the work needed to open unit volume of cavity, Ps, which is the key parameter in studying penetration problems, is linearly increasing with the characteristic strain rate. The application of Ps to our quasi-static and high-speed penetration experiments is discussed and assessed.