and the diffusive backflow of rejected solute from the parent phase to the
nucleated phase.
The tree-like oscillatory layered structure is often observed
during the directional solidification of peritectic alloys, especially
when the diameters of the samples are large, which was
due to the convection in the Bridgman directional solidification
[14]. Mazumder et al. [5] found that when the convection is
steady, a curved interface between primary phase and peritectic
phase forms, whereas when the convection is oscillating, the
structure of tree-like primary phase surrounded by the peritectic
phase usually forms.
Peritectic coupled growth (PCG), the prospective method
to produce in situ composites in peritectic systems, has been
discussed for many years [15]. Boettinger [2] examined PCG
using the eutectic theory developed by Jackson and Hunt [16],
and found that a negative undercooling of the coupled growth