Fig. 1. Experimental procedures in this study: (a) illustration of the Bridgman-type directional solidification equipment and (b) the measurement of SV in the transverse sections of a rod.

Fig. 2. Typical microstructures of the dendritic morphology in Sn-36at.%Ni: 5 μm/s (a), (d); 20 μm/s: (b), (e); 40 μm/s: (c), (f). (a)-(c) shows the microstructure at the solid/liquid interface and (d)-(f) shows that at the peritectic interface.

Fig. 3. Dependence of transversal microstructures of the dendritic morphology in Sn-36 at.%Ni at the growth velocity of 5 μm/s: (a) the positions and corresponding temperatures of these transversal microstructures; (b)-(e) shows the microstructures at different transversal sections, which correspond to TI, TII, TIII, TIV, respectively.

Fig. 4. Illustration of the comparison between the TGZM and G-T effects on their influences on remelting/resolidification process in stage I during directional solidification of peritectic alloy.

Fig. 5. Illustration of the comparison between the TGZM and G-T effects on their influences on remelting/resolidification process in stage II during directional solidification of peritectic alloy.

Fig. 6. Illustration of the comparison between the TGZM and G-T effects on their influences on remelting/resolidification process in stage III during directional solidification of peritectic alloy.

Fig. 7. Illustration of the comparison between the TGZM and G-T effects on their influences on relting/resolidification process in stage IV during directional solidification of peritectic alloy.

Fig. 8. Schematic illustration of the cross section of the thin arm after peritectic reaction, showing the definitions of rp, rα and rβ.

Fig. 9. Comparison between the theoretical prediction and experimental results of permeability K in directionally solidified Sn-36at.%Ni peritectic alloy at different growth velocities when the TGZM effect is not taken into consideration: (a) 5 μm/s, (b) 10 μm/s, (c) 20 μm/s and (d) 40 μm/s.

Fig. 10. Comparison between the theoretical prediction and experimental results of permeability K in directionally solidified Sn-36at.%Ni peritectic alloy at different growth velocities when the TGZM effect is taken into consideration: (a) 5 μm/s, (b) 10 μm/s, (c) 20 μm/s and (d) 40 μm/s.