<i>In situ</i> radiographic and <i>ex situ</i> tomographic investigation of pore collapse in laser shock-loaded polyurethane foam

Laser-driven shock experiments were conducted at a synchrotron facility to investigate the dynamic response of polyurethane foam. These coupled in situ x-ray imaging radiograph foam deformations and determine propagation velocity stress waves. To increase amplitude duration pressure load generated by laser–matter interaction, front surface target was covered with confining layer (water BK7 glass). Preliminary calibration tests involving time-resolved measurements performed calculate ablation on samples. The calculated loads used as input data for hydrodynamic simulations, which is modeled using homogeneous porous macroscopic model, model predictions compared experimental results. A fair consistency found most experiments, while others, an overestimation applied suspected, likely due laser breakdown within medium. Finally, post-shot tomography recovered samples showed permanent deformation foam, unlike what observed under quasi-static compression, revealed heavy damage vicinity loaded zone.