Corrosion characteristics of T91 steel in lead–bismuth eutectic with different oxygen concentrations at 500°C. Issue 1 (14th September 2021)

• Record Type: Journal Article
• Authors: Tian, Shujian; Pang, Yongqiang; Jiang, Zhizhong; Luo, Lin; Xiao, Zunqi
• Is Part Of: Materials and corrosion. Volume 73:Issue 1(2022)
• Page Start: 134
• Page End: 142
• Publication Date: 2021-09-14
• Subjects: corrosion -- lead‐based reactor -- lead–bismuth eutectic -- T91; Materials -- Periodicals; Metals -- Periodicals; Corrosion and anti-corrosives -- Periodicals; 620.1122305
• DOI: 10.1002/maco.202112505
• Languages: English
• ISSNs: 0947-5117

Abstract

Abstract: Corrosion tests of T91 were carried out in the stagnant lead–bismuth eutectic (LBE) containing 10 −6, 10 −7, and 10 −8 wt% oxygen at 500°C for up to 2000 h, respectively. The dependence of corrosion characteristics on oxygen concentrations in LBE was obtained. The results show that the oxide‐scale structure changes from a three‐layer magnetite/spinel/internal oxidation zone (IOZ) scale under the oxygen concentration of 10 −6 wt%, to the formation of a two‐layer spinel/IOZ scale under the oxygen concentrations of 10 −7 and 10 −8 wt%. In addition, with the decrease of the oxygen concentration, the Cr/Fe ratio in the Fe–Cr spinel slightly increases in a linear rule while the thicknesses of the oxide layers gradually decrease. Abstract : With the decrease in the oxygen concentration from 10 −6 to 10 −8 wt%, the oxide scale structure changes from a three‐layer scale to a two‐layer scale, and the total thicknesses of the oxide scale have a similar varying tendency, which reaches about 20.5, 8.2, and 7.3 µm after exposure for 2000 h, respectively. The results show that oxygen concentration plays a key role in the oxide scale growth.