Shock‐wave compaction of porous aluminum

Experimental data on the shock‐wave compaction of 78% dense porous aluminum are presented and compared with theoretical predictions from a mathematical theory of time‐dependent pore closure for ductile materials with isolated spherical voids. A recently modified form of the theory was used which includes deviatoric stresses and material viscosity. Incorporation of the work‐hardening properties of the solid resolved previous discrepancies between measured hydrostats and predictions assuming elastic‐perfectly plastic deformation of the matrix. Generally good agreement was also observed between experimental quasistatic and shock data, although there was some evidence that the quasistatic data were strain‐history dependent. Finally, a satisfactory check of the theory was obtained by comparing predicted steady‐wave rise times with measured stress‐wave profile data. These results suggest that the current version of the theory is a significant improvement over past models, because it permits a more accurate estimate of the influence of both pore size and the plastic deformation characteristics of the metal matrix on shock compaction.Experimental data on the shock‐wave compaction of 78% dense porous aluminum are presented and compared with theoretical predictions from a mathematical theory of time‐dependent pore closure for ductile materials with isolated spherical voids. A recently modified form of the theory was used which includes deviatoric stresses and material viscosity. Incorporation of the work‐hardening properties of the solid resolved previous discrepancies between measured hydrostats and predictions assuming elastic‐perfectly plastic deformation of the matrix. Generally good agreement was also observed between experimental quasistatic and shock data, although there was some evidence that the quasistatic data were strain‐history dependent. Finally, a satisfactory check of the theory was obtained by comparing predicted steady‐wave rise times with measured stress‐wave profile data. These results suggest that the current version of the theory is a significant improvement over past models, because it permits a more accurate esti...