Analysis of corrosion scale structure of pre-oxidized stainless steel 316 in molten lead bismuth eutectic and the relation to impedance spectroscopy response

Impedance spectroscopy and microstructural characterization of the corrosion behavior of FeCrAl alloy in lead–bismuth eutectic

“…2a illustrates the surface SEM picture of a specimen after immersion in LBE for 3600 h. The surface oxide morphology is quite different from the oxide formed on SS316 under the same corrosion conditions [22]. In current study, the shape of surface oxide particles is more irregular and the particles tend to combine together while the oxide particles formed on SS316 from Ref.…”

“…In the previous work, techniques for the application of IS to study corrosion-based scale development in SS316 at 550°C were developed. However negligible levels of impedance were measured in that study [22]. The negligible impedance magnitude measured from SS316 indicates that protective oxide layers which are impermeable to LBE did not form continuously over the entire sample surface.…”

“…The experimental setup for the IS tests (referred as ''IS setup'' hereafter) has been described previously [22]. In this work, a new setup (referred as the ''corrosion setup'' hereafter) for performing static corrosion test in LBE was established.…”

“…Therefore 45 specimens in total can be tested at the same time in the corrosion setup. To avoid excessive LBE oxidation at high temperature, the same environmental control method was employed for the corrosion setup as the previous IS setup [22]. The environment inside the quartz tube was controlled by flushing pure argon gas into the tube via the gas inlet at one end of the tube and sealing the other end of the tube from air by connecting it to an oil bubbler.…”

The electrical AC impedance response of oxide scales on 9Cr–1Mo steel immersed in molten lead–bismuth eutectic alloy at 200 °C

“…Although the thickness of the oxide scale was not measured, an estimate of 10 lm would imply that the conductivity was about 1 Á 10 -8 S/cm to 3 Á 10 -8 S/cm. Chen et al used impedance spectroscopy on oxidized SS316 and FeCrAl alloys in LBE at 550°C [8,9]. They observed negligible impedance response from the SS316 samples, probably because the oxide scale on SS316 did not cover the surface uniformly and also contained cracks.…”