Artículos de revistas
Cellular spacings in unsteady-state directionally solidified Sn-Pb alloys
Registro en:
Materials Science And Engineering A-structural Materials Properties Microstructure And Processing. Elsevier Science Sa, v. 361, n. 41671, n. 111, n. 118, 2003.
0921-5093
WOS:000186354700015
10.1016/S0921-5093(03)00518-5
Autor
Rocha, OL
Siqueira, CA
Garcia, A
Institución
Resumen
Solidification thermal parameters, i.e. transient metal/mold heat transfer coefficient, tip growth rate and cooling rate, and cellular spacings have been measured in dilute Sn-Pb alloys solidified under unsteady-state heat flow conditions. It has been found that the cellular spacings decreased with increasing solute content up to the limit of the cellular range, at about 2 wt.% Pb. A sharp increase in spacing is observed when the growth morphology changes from cellular to cellular/dendritic. The Hunt-Lu's model applied to cellular growth did not generate the experimental observations for the alloys examined in the present study. It is proposed the insertion of analytical expressions for tip growth rate and cooling rate into the resulting experimental equations permitting to establish empirical formulae relating cellular spacings with unsteady-state solidification parameters like: melt superheat, type of mold and transient metal/mold heat transfer coefficient. (C) 2003 Elsevier B.V. All rights reserved. 361 41671 111 118