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NonCommercial-ShareAlike 4.0 International
https://creativecommons.org/licenses/by-nc-sa/4.0/
Alloy
W lies in the liquid phase
field at high temperatures.
It cools through the liquid region
until it reaches the liquidus
and crosses into the two phase region.
field at high temperatures.
It cools through the liquid region
until it reaches the liquidus
and crosses into the two phase region.
The
two phase region is composed of
a stack of isothermal sections. Multiple
tie lines lie in each section.
As alloy W cools through the two
phase region, it passes through a
series of isothermal sections.
a stack of isothermal sections. Multiple
tie lines lie in each section.
As alloy W cools through the two
phase region, it passes through a
series of isothermal sections.
As
alloy W cools, the equilibrium
compositions of the solid and liquid
change according to the ends of the tie
lines spanning the region (shown by
blue and red dots respectively).
compositions of the solid and liquid
change according to the ends of the tie
lines spanning the region (shown by
blue and red dots respectively).
It
is clear to see that the equilibirium
compositions of the solid and the liquid
do not lie in a single plane. The tie
lines rotate with decreasing
temperature.
compositions of the solid and the liquid
do not lie in a single plane. The tie
lines rotate with decreasing
temperature.
The paths of the solid and liquid
compositions are shown.
Eventually
the alloy reaches the solidus
temperature and passes into the single
phase solid region. Alloy W then cools
through the solid region.
temperature and passes into the single
phase solid region. Alloy W then cools
through the solid region.