富锑铅锑熔体电阻率及黏度的异常变化(英文)

Abnormal resistivity and viscosity behavior in Sb-rich Pb-Sb melts

通过测量PbSb合金熔体的电阻率及黏度,探讨熔体中Peierls畸变的演变。Pb30Sb70、Pb20Sb80和Pb10Sb90在降温过程中具有非线性电阻率温度关系。在663°C下,实验与计算的等温电阻率成分关系的变化趋势不同,也暗示了富Sb熔体中Peierls畸变的存在。Pb20Sb80与Pb30Sb70熔体的异常的黏度温度关系证实了异常结构转变的存在,这种异常转变被认为是具有Peierls畸变的大尺寸Sb团簇的形成。在过冷液态Pb20Sb80中,由于提高了熔体与晶态固体的结构相似性并降低了液固界面能,含有Peierls变的Sb团簇在凝固过程中提供优先的形核位;抛物线的电阻率温度关系及极小的电阻率系数被认为是由这些Sb团簇尺寸的快速增加而导致的。

Electrical resistivity and viscosity of Pb–Sb alloys are measured to investigate Peierls distortion behavior in the melts. In Pb30Sb70, Pb20Sb80, and Pb10Sb90 melts, temperature dependence of resistivity deviates from linear dependence during cooling. At 663 °C, different trends in isothermal behavior between experimental and theoretical resistivities, are interpreted as the existence of Peierls distortion in Sb-rich melts. In Pb30Sb70 and Pb20Sb80 melts, abnormal viscosity results verify the existence of abnormal structure transition, which is attributed to the formation of large Sb clusters with Peierls distortion. In undercooled liquid Pb20Sb80, minute resistivity coefficient and quadratic resistivity behavior are interpreted as the rapid increase of cluster size of Sb clusters with Peierls distortion, which provides preferential nucleation sites for higher structure similarity to the crystalline and lower liquid–solid interfacial energy.