The electrical resistivity of liquid In-Sn alloy was measured by a dc four-probe method. In a relatively low-temperature zone above liquidus, resistivity changes discontinuously; only the changing trend is altered, whereas resistivity changes sharply in the high-temperature zone and the changing pattern is completely different from the ones at low temperature. The unusual change of resistivity reflects the alteration of the mean free path L 0 of conduction electrons and also the electron transport properties. Consequently, we assume that structural changes might occur in the continuous heating process. Transition temperatures are different for In-Sn melts with various compositions. The resistivity behaviour of eutectic composition is distinguished from others and its transition temperature is the lowest.

An investigation of the temperature dependence of the electrical resistivity (ρ–T) of Sn–Sb alloys is carried out, using the DC four-probe method. A clear turning point is observed in some compositions of the Sn–Sb melt, but not at every composition, at which the resistivity–temperature coefficient increases rapidly. The anomalous variation of the resistivity at certain temperatures for the Sn–Sb melt may be due to the remaining covalent and heterogeneous bonds and also the difference in bonding ability between Sn and Sb atoms, which might yield temperature-induced structure changes in some compositions of liquid Sn–Sb alloys. Besides this, analysis of the composition dependence of the resistivity is also included in this paper.

Up to now, there have been few studies of the temperature-induced liquid–liquid structure transition (LLST) kinetics for atomic systems. In this paper, through isothermal and heating experiments, we have investigated the kinetics of the LLST process in Pb–Sn61.9 wt% melt by measuring the electrical resistivity and heat flux. The time evolution of the heat flux and electrical resistivity can be described by the Johnson–Mehl–Avrami model with an Avrami exponent of 3.87, which is an indication of nucleation-growth-type ordering of the nonconserved order parameter. What is more, we have calculated the reaction rate constant KT and apparent activation energy ΔE, and deduced the reason for the characteristics of temperature-induced LLST. The result of this research could be beneficial for a further understanding of the essence of LLST.

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