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Those peritectic alloys with large positive mixing enthalpy usually display metastable liquid phase separation. Here, the solidification kinetics for a model Fe 50 Cu 50 alloy in broad cooling rate R c range was predicted by phase-field simulations and confirmed by drop tube experiments. Near-equilibrium peritectic solidification occurs in small R c regime below 5.62×10 2 K s −1 . As R c rises beyond 7.76×10 2 K s −1 , metastable phase separation takes place and results in the formation of a dispersed structure. Afterwards, multilayer core-shell structures appear, and the layer-number varies from two-layer to six-layer with further increasing R c . Once R c exceeds 3.64×10 5 K s −1 , a dispersed structure once again forms because the core-shell dynamic condition is not satisfied. Non-equilibrium peritectic solidification is induced if R c is greater than 5.85×10 5 K s −1 . [ABSTRACT FROM AUTHOR]

Supersaturated Ni–Sn solid solutions with Sn solubility up to 9.2 at% have been obtained through rapid solidification in the undercooling range of 220–280 K. The lattice properties including the lattice constant, microscopic lattice distortion, thermal expansion and linear expansion coefficient are investigated experimentally and theoretically. The lattice constants increase about 0.01 Å per 1 at% Sn in linear way. The lattice distortions are mainly confined to the first nearest-neighbor atoms with the values of (3.5±0.3)%, and are less than 1% for farther atoms. The thermal expansions vary only a little with Sn content and exhibit obvious increase for the as-cast solid solutions above 1150 K due to the phase transformation of Ni 3 Sn compound, whereas they increase smoothly with temperature for the annealed supersaturated samples. [ABSTRACT FROM AUTHOR]