TITLE:
MD Simulated Microstructure of Liquid Sodium Alloyed with Lead
AUTHORS:
Inessa Yu. Shimkevich, Alexander L. Shimkevich
KEYWORDS:
Molecular Dynamics, Liquid Sodium, Lead and Thallium Additives, Micro-Heterogeneous Alloys
JOURNAL NAME:
Materials Sciences and Applications,
Vol.5 No.8,
June
27,
2014
ABSTRACT: The results of molecular-dynamics (MD) simulation are obtained for structural
and thermodynamic properties of the molten system, Na1-xPbx (x ≤ 0.1), at
698 K in the model of nearly free electronic gas (NFE approximation). The all numerical
experiments are carried out by unified procedure: 1) equilibrating the MD cell 1
ps; 2) calculating partial radial distribution functions gab(r) in
1, 5, and 10 ps; 3) data handling for calculating other characteristics. It follows
from this that lead impurity in liquid sodium at concentration in the range of 1%
- 10% is characterized by micro-heterogenetic structure in the form of cluster compounds
with variable composition. Just therefore the sodium alloys, Na-MIV,
with four-group elements of Periodic table have no eutectic in this range of additive
concentrations. This eutectic is needed for modifying sodium coolant of the fast
nuclear reactor. Therefore it is reasonable to find an alternative alloy of sodium
with additive from adjacent groups which has a eutectic in this range of concentrations,
for example, the eutectic, Na0.929Tl0.071, with melting point
of 64°C. The modified sodium coolant by isotope, 205Tl, can appear attractive
for inhibiting the chemical activity of sodium just as the lead alloyed one.