Anomalous change of electrical resistivity with temperature in liquid Pb-Sn alloys

The patterns of electrical resistivity of lead-tin (Pb-Sn) alloys with different compositions, along with pure liquid lead and tin, have been investigated as a function of temperature, using the DC four-probe technique. Evident turning points are observed on resistivity-temperature curves of the four liquid Pb-Sn alloys, and the resistivities increase linearly with rising temperature before the turning points. Moreover, the turning points are all at the temperature scope far above the liquidus. In case of both liquids pure lead and tin, however, the resistivity-temperature curves are linear within the measured temperature. Since resistivity is one of the physical properties sensitive to structures, it is suggested that there are temperature-induced structure changes in the liquid Pb-Sn alloys.