If the d phase solidifies at
DT > DT*, it will transform into the c phase in the solid
state during continuous cooling. In contrast, if the c
phase prevails, there will be no such solid-state transformation.
Thus, the thermal recalescence recorded in the
single c phase area (Fig. 1b) can directly confirm the
occurrence of the solid-state d ! c transformation. Furthermore,
if the d ! c transformation is not complete,
the untransformed d phase will be preserved as a-ferrite
at RT.