| |
|
· The solid phase has a concentration
gradient between the center and the surface and its average composition
follows the non-equilibrium solidus shown on the phase diagram.
· The final average composition of the
solid must be the same as that of the initial liquid phase, Cu-40
wt % Ni,
as matter is conserved.
· All
phase transitions take place at a finite rate and involve the nucleation
and growth of a new phase from an existing one.
· The stable phase at any temperature is that with the lowest
Gibbs
function and phases in equilibrium have the same Chemical
Potential.
· An important issue in phase transformation
will be the manner in which nucleation and growth takes place.
· Material property control of
is possible since their temperature-time history determines their microstructure.
|
|
