Electrical properties of thermal oxide scales on pure iron in liquid lead-bismuth eutectic

TL;DR

This study investigates the electrical properties of oxide scales on pure iron in liquid lead-bismuth eutectic, revealing how oxidation conditions affect impedance and defect levels in the oxide film.

Contribution

It provides new insights into how oxidation temperature and duration influence the impedance and defect structure of iron oxide scales in LBE environments.

Findings

Oxide resistance increases with higher oxidation temperature.

Longer oxidation time reduces defect concentration in oxide films.

Thicker oxide scales correlate with higher impedance.

Abstract

The impedance behavior of pre-oxidized iron in liquid lead-bismuth eutectic (LBE) at 200 oC is studied using electrochemical impedance spectroscopy. The structures and resistance of oxide grown on iron oxidized in air at different temperatures and durations are compared. The results show that the resistance of the oxide film increases with increasing oxidizing temperature, due to the formation of a thicker scale and fewer defects. At the same temperature (600 oC), increasing the oxidation time can also reduce the defect concentration in the oxide film and improve the impedance of the oxide scale in LBE.