Oxidation behavior of T91 steel in flowing oxygen‐containing lead‐bismuth eutectic at 500 °C

Abstract

T91 is considered as a possible structural material for lead‐bismuth eutectic (LBE) cooled reactors. However, one of the main issues is the compatibility of T91 with LBE. In this work, the corrosion tests of T91 were performed in flowing (1 m/s) oxygen‐controlled LBE (1–3 × 10−6 wt% O) at 500 °C for up to 5000 h. The results show that a three‐layer oxide scale forms at the interface of T91 and LBE, consisting of Fe3O4 (magnetite), Fe‐Cr spinel and an internal oxidation zone (IOZ). The growth kinetics of the oxide scale follows a parabolic dependence (Δx2=knormalpt). The rate constants (kp) of Fe3O4, Fe‐Cr spinel, and IOZ are 0.052, 0.040, and 0.0057 μm2/h, respectively. In addition, the growth model of the oxide scale is established under consideration of the exfoliation process. This model clarifies the growth direction of each oxide layer and the transformation of Fe‐Cr spinel to magnetite.

Environmental degradation of structural materials in liquid lead- and lead-bismuth eutectic-cooled reactors

“…Mechanisms: uniform oxidation (diamonds), uniform dissolution (circles), and locally enhanced dissolution (triangles). [92,101,115,117,172,180,181,183,185,187,[189][190][191][215][216][217]219,225,227,[230][231][232]234,[237][238][239][240]. Mechanisms: uniform oxidation (diamonds), uniform dissolution (circles), and locally enhanced dissolution (triangles).…”

“…HLMs: LBE, Pb, Bi, 36Pb-64Bi, 26Pb-74Bi. Data collected from Refs [92,101,115,117,172,180,181,183,185,187,[189][190][191][215][216][217]219,225,227,[230][231][232]234,[237][238][239][240]…”

“…The bars indicate cases of localised dissolution resulting from exposures to C O ranges. Data collected from Refs [92,101,115,117,172,180,181,183,185,187,[189][190][191][215][216][217]219,225,227,[230][231][232]234,[237][238][239][240]…”

Cohesive properties of PbBi/Fe3O4 and PbBi/(Fe,Cr)3O4 interfaces

“…[13][14][15][16] In addition, Tian et al found that the shedding of the oxide layer plays an important role in the corrosion rate of steel in the LBE. 17 Recently, theoretical simulations were also conducted to obtain the corrosion information of steel and its oxides in the LBE. Recently, Xu et al investigated the adsorption of Pb, Bi and Au atoms and escape of Fe atoms from iron surfaces in liquid metals.…”

A Review of the Surface Modifications for Corrosion Mitigation of Steels in Lead and LBE

“…This option is not recommended for high temperature applications (above 500 • C) because the kinetics of oxide growth is fast. This would result in a thick and weakly adherent layer of oxide [45,46]. Thus, reduction in thermal conductivity, oxide spallation, and channel plugging are arising issues.…”