Denucleation and deep undercooling of Ni-32.5%Sn eutectic alloy

Cyclic superheating and denucleating with inorganic glasses were applied to melt of Ni-32.5%Sn eutectic alloy, and deep undercooling down to 397K(0.283T_E) was obtained. It was found that the predominant way of heat dissipation for deeply undercooled alloy melt is through radiation. An approximate method for the calculation of average specific heat based on measured cooling curves was derived. With the aid of high speed cinematography, it was revealed that the surface or interface heterogeneous nucleation takes place in preference to homogeneous nucleation even the degree of undercooling exceeds 0.2T_E.