Numerical simulation investigation in behavior of Al-foams structure under hypervelocity impact

The existing Equation of State and Strength Model, which regard foams as homogeneous medium, can't exactly describe the characterizations of metallic foams because the pore is big enough not to be ignored compared with projectile or bumper. In the article, Foams were regarded as discontinuous medium and pores of different size and position, fitted to some distribution and filled with void, were created in the metal to model the real geometry. Naturally material parameters needed for metallic foams are just those of original metal material, which have been developed extensively and successfully. A 3-dimansional Smoothed Particle Hydrodynamics (SPH) program with the foam model was developed. Simulations of normal impact on double bumpers, consisting of aluminum bumper and open-cell aluminum foam bumper, and aluminum rear wall were carried out and compared with test data. Good agreement was obtained. Then, the behavior of different Al-foams was investigated by numerical simulations.