Rapid dendritic growth within an undercooled Ni-Cu-Fe-Sn-Ge quinary alloy

A liquid quinary alloy with composition Ni-5%Cu-5%Fe-5%Sn-5%Ge has been prepared from a containerless state by undercooling. Dendritic growth of α-Ni phase took place with a velocity of 28 m s-1 at the maximum degree of undercooling, which was as high as 405 K (0.24TL). All of the four solute elements Cu, Fe, Sn and Ge exhibited a significant solute trapping effect during the rapid dendrite growth. Segregation-less solidification is consequently realized when the degree of undercooling is sufficiently large. The lattice constant of α-Ni solid solution phase is found to increase with the amount of multicomponent solute trapping.