Hugoniot and spall strength measurements of porous aluminum

Plate impact experiments were performed on 14% porous aluminum samples to measure the principal Hugoniot and the spall strength. The principal Hugoniot was measured by performing multiple experiments at a range of flyer velocities, from 0.25–0.89 km/s, leading to incident shock pressures in the target from 0.6–4.8 GPa. The shock compaction data were compared to a theoretical Hugoniot determined from a Mie–Grüneisen equation of state and was found to agree very well over the stress range investigated. Spall strength measurements were performed on the 14% porous aluminum samples at impactor velocities of 0.224, 0.230, and 0.306 km/s. Spall strengths of 78±8, 55±28, and 36±7 MPa, respectively, were measured for the porous Al samples. This is thought to be the first measurement of spall strength in a shock compacted porous ductile material.