INVESTIGADORES
BRINGA Eduardo Marcial
artículos
Título:
Simulation of shock-induced melting of Ni using molecular dynamics coupled to a two-temperature model
Autor/es:
L. KOCI; E.M. BRINGA; DMITRIY S. IVANOV
Revista:
PHYSICAL REVIEW B
Editorial:
AMER PHYSICAL SOC
Referencias:
Año: 2006 vol. 74 p. 12101 - 12106
ISSN:
1098-0121
Resumen:
Using nonequilibrium molecular dynamics (MD) simulations we study
shock-induced melting in Ni with an embedded atom method (EAM). Dynamic
melting is probed by the pair correlation function, and we find a
melting lattice temperature of Tmelt=6400±300 K for a melting pressure of Pmelt=275±10 GPa.
When a combined MD+TTM (two-temperature model) approach is used to
include electronic heat conduction and electron-phonon coupling, Pmelt and Tmelt
change. For a given pressure, the temperature behind the shock
decreases due to electronic heat diffusion into the cold, unshocked
material. This cooling of the material behind the shock slightly
increases the melting pressure compared to simulations without
electronic heat conduction and electron-phonon coupling. The decrease in
the temperature behind the shock front is enhanced if the
electron-phonon coupling is artificially made larger. We also explore
the feasibility of using x-ray diffraction to detect melting.