Clustering of Fe atoms in liquid Li and its effect on the viscosity of liquid Li

Abstract

The clustering processes of Fe atoms in liquid Li at different temperatures and the effect from the Fe clusters on the viscosity of liquid Li are investigated using molecular dynamics simulation combined with the embedded atom method. The clustering processes are vividly captured by the microstructure evolution snapshots and the details are uncovered by the cluster analysis results. The cluster analysis results indicate the higher the temperature the faster the clustering process, and the temperature-dependent mixing enthalpy of Li–Fe (solute) dilute solution also suggests that high temperature is beneficial to Fe atoms’ clustering. In addition, our results show that the Fe clusters can dramatically increase the viscosity of liquid Li by lowering the diffusivity of the Li atoms around it, and the larger the clusters the larger the viscosity increment.

Molecular dynamics study on the slippage of liquid lithium flow in tungsten nanochannels

“…It increases rapidly as approaching to the walls since the velocity gradient decreases notably while the averaged shear stress keeps constant. Beyond a certain distance (≈10 Å), which is also the thickness of the layered Li atoms, the effective viscosity remains constant and equals the value of bulk liquid Li, 3.2 × 10 −4 Pa s. This value is a bit smaller than the experimental result, 4.3 × 10 −4 Pa s [36], and coincides with other published MD results, 3.3 × 10 −4 Pa s [37].…”