Shock loading of M3 copper within strain rate range of
5·10
6
-
5,7·10
6
s
-1
reveals a
nucleation of structural objects of 5
-
30 μm
in diameter, which
present the three dimensional
frameworks composed from shear bands of 50
-200 nm spacing. The structures are shown to
be nucleated by means of interference of longitudinal and periphery release waves. Transition
of the material into structure unstable state responsible for the shear banding happens when
rate of change of the velocity variance at the mesoscale becomes higher than the rate of
change of the mean particle velocity. The sites of nucleation of 3
D-structures are speculated
to be the staking faults generated under action of chaotic velocity pulsations relevant to
dynamic deformation.
The physical model for formation of 3D-structures takes into account
the
intersection of
the partial dislocations
and Lomer -
Cottre
ll barriers.