Laser driven shocks allow studying the dynamic behaviour of condensed matter over small spatial (similar to mu m to mm-order) and temporal (similar to ps to ns-order) scales, at extremely high strain rates (similar to 10(7) s(-1)). They can be used to test the predictive capability of constitutive models over wide ranges of loading pressures and pulse durations. We present experimental results in laser shock-loaded metals (iron, gold, tin), based on various, complementary techniques including time-resolved velocity measurements, transverse shadowgraphy and post-shock analyses of recovered samples. The data are used to investigate several shock wave processes such as yielding and polymorphic transformations, melting, spall fracture and dynamic fragmentation in both solid and melted states. On the basis of comparisons with numerical simulations, the abilities and limitations of several models are briefly discussed.
from HAL : Dernières publications http://ift.tt/1FNITrT
from HAL : Dernières publications http://ift.tt/1FNITrT

0 commentaires:
Enregistrer un commentaire