DENUCLEATION AND HIGH UNDERCOOLING OF Ni-32.5%Sn EUTECTIC ALLOY
Ni—32.5%Sn共晶合金的净化与深过冷

Large undercooling up to 397 K (0.283T_E) have been obtained for Ni-32.5%Sn eutectic alloy melt by superheating-cooling cycles and denucleating withinorganic glasses. The predominant dissipation of heat for highly undercooled alloymelt is through radiation. An approximate method was consequently derived to cal-culate its mean specific heat from measured cooling curves. With the aid of highspeed cinematography, it was revealed that the surface or interface heterogeneousnucleation takes place in preference to homogeneous nucleation even though theundercooling exceeded 0.2T_E.