Numerical And Experimental Investigation On Penetration Effects Of Semi-Armor-Piercing Warhead

The Semi-Armor-Piercing Warhead (SAPW) is a combination of both kinetic energy penetrator and explosive warhead, it should ensure the structural integrity during penetration process. While the high explosive inside the warhead occupies a large space and its strength is much smaller than that of the metal, the ability to resist the shell deformation of warhead is weaken. The deformation and strength of warhead shell in the penetration process is an important aspect in the SAPW research.In this paper, the numerical and experimental investigations are carried out on the project of supersonic SAPW penetrating into metal targets. Firstly, we obtain the material parameters of dynamic constitutive relationship used in numerical simulations through dynamic material tests. Experiments and numerical simulation of Taylor impact are conducted to verify the rationality of the material parameters. Secondly, through the numerical simulations of deformable blunt projectile impacting deformable target, and the experimental and numerical studies on the truncated-conical projectiles penetrating thin steel plates at various oblique angles, the numerical method and modeling are further validated. Finally, the penetrations of supersonic SAPW into metal targets are simulated by the means of the set-up numerical method and modeling. The research focuses on the structural integrity of warhead.Dynamic and quasi-static mechanical behaviors of 45 steel and TC4 titanium alloy are studied with Split Hopkinson Pressure Bar (SHPB) and Material Test System (MTS) over a wide range of strain rate and temperature. The parameters of Johnson-Cook material model are determined through these experiments, and are evaluated with comparing the results of experiments and numerical simulation of Taylor impact. The consistency between experimental observations and numerical simulations indicates the material parameters obtained can describe the large strain mechanical behavior of 45 steel and TC4 titanium alloy under high speed deformation.The effects of high strain rate, elevated temperature and stress state triaxiality on the fracture behaviors of 45 steel and TC4 titanium alloy are further studied. The fracture characters of 45 steel and TC4 titanium alloy strongly depend on the stress triaxiality. The critical failure stain of 45 steel decreases monotonously with increasing the value of the stress state triaxiality. Quite differently for TC4 titanium alloy, it was observed that shear-fracture mode dominates in regime of negative stress triaxiality while void growth is the dominant failure mode in regime of stress triaxiality above 1/3. Fracture may develop with hybridizing shear and void growth at low stress triaxiality between above two regimes.Different dynamic fractures occur in the Taylor tests when the specimens of 45 steel and...