Exploration Of Temperature-induced Liquid-Liquid Structure Transition Of Sn-Zn And Pb-In Alloy

Recently, the structures and their change characters in liquid alloys have become one of the most active areas in condensed matter physics and science. As one of sensitive parameters to structure, electrical resistivity can make people investigate the interaction between atoms and electrons. Moreover, modern technology in measure makes it possible to obtain accurate electrical resistivity and temperature coefficient of resistivity (TCR). In this paper, we carry out investigation of the temperature dependence of electrical resistivity (p-T) using DC four-probe method for liquid Sn-Zn and Pb-In alloy systems. It is helpful to explore the universality of temperature-induced liquid-liquid structure transition (T-LLST) in alloys.During the investigation of the electricity behavior in Sn-Zn alloys with increasing temperature, it is found that some abnormal changes occur at high temperature for Sn-Zn melts, which is similar to those in other binary alloys. But such changes are considered the causation of the gasification of Zn component in Sn-Zn alloys, namely the liquid-gas structure transition occurs during this process. And the gasification temperatures are different with the change of Zn concentration in Sn-Zn alloys, owing to the variety of bonding force in various melts. However, no T-LLST is suggested to exist in Sn-Zn melts.Furthermore, the p-T curves of Pb-In melts are also investigated in both heating and cooling. An abnormal change of electrical resistivities can be seen on each p-T curve when the temperature becomes high enough and it vanishes with succedent increasing temperature. Such abnormal changes of electrical resistivities are regarded as the results of the LLST in Pb-In metis, which are validated by DSC experiments. Moreover, the structure transition temperatures are various for each composition. However the results of resistivity method and DSC in cooling for Pb-In63wt% melts indicate that such transition is irreversible.The experimental investigations of the two alloy systems suggest that the T-LLST does not always exist in every alloy system. These results are useful to recognize the universality T-LLST of in alloys.