WIT Press


Thermodynamieally Consistent Phase-field Models Of Solidification Processes

Price

Free (open access)

Volume

18

Pages

10

Published

1997

Size

793 kb

Paper DOI

10.2495/MB970031

Copyright

WIT Press

Author(s)

C. Charach & P.C. Fife

Abstract

Diffuse interface models of nonisothermal solidification of a pure substance in an undercooled melt are reconsidered in the frame of Extended Irreversible Thermodynamics. The gradient terms are allowed not only in the free energy and entropy densities but also in the internal energy density. Requiring the local entropy production to be nonnegative we derive a one- parameter family of field equations for the nonconserved order parameter coupled to the heat conduction. The meaning of the above gradient terms is clarified by considering stable and metastable two-phase equilibria. For nonisothermal growth processes we present some asymptotic resul

Keywords