Dendritic growth in undercooled monotectic alloys

Abstract

Bulk samples of Ni-11. 5at% Pb and Fe-32. 1at% Sn monotectic alloys were undercooled by up to 218K and 172K respectively. The growth velocity of the solid phase during rapid monotectic solidification was measured and also calculated according to the current dendritic growth theories. It is found that the solid phase grows dendritically in the undercooled monotectic alloy melts and that its growth is controlled mainly by solute diffusion, since the slow cooling rate allows Stokes motion longer periods of time, bulk rapid solidification of undercooled monotectic alloys results in macrosegregation on sample surface.