Cyclic Supercooling of Liquid Bismuth Drops during Solidification

Resumo

The laws of changing the presolidification supercooling of bismuth drops during continuous thermal cycling were studied by thermal analysis in the temperature–time coordinates. A sawtooth cyclic dependence of the supercooling on the sequence of heating and cooling cycles, which is described by a Fourier function, is detected. An expression is derived for the energy of coagulation of nuclei, and it is used to find a relation between the experimental and calculated supercoolings. The obtained results are interpreted in terms of a cluster-coagulation solidification model and the anomalous properties of bismuth in melting and solidification.