Investigation of impurity driven corrosion behavior in molten 2LiF-BeF2 salt. (September 2020)

• Record Type: Journal Article
• Authors: Doniger, William H.; Falconer, Cody; Elbakhshwan, Mohamed; Britsch, Karl; Couet, Adrien; Sridharan, Kumar
• Is Part Of: Corrosion science. Volume 174(2020)
• Publication Date: 2020-09
• Subjects: Molten salt corrosion -- 2LiF-BeF2 -- 316H stainless steel -- Impurities -- Cyclic voltammetry; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2020.108823
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: CrF2 and FeF2 are influential over the microstructure and weight change of 316H stainless steel in molten 2LiF-BeF2 . The concentration of trace Cr and Fe impurities in 2LiF-BeF2 can be determined before and after corrosion using ICP-OES. Voltammetry methods can distinguish between trace impurities, such as dissolved CrF2 and FeF2 . Abstract: A 1000 -h corrosion experiment of 316H stainless steel at 700 °C investigated the role of metal fluoride impurities CrF2 and FeF2 in LiF-BeF2 (66-34 mole %) (FLiBe) salt. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) demonstrated the ability to measure changes in the concentration of these fluorides in FLiBe salt. Cyclic voltammetry (CV) showed the potential for real-time quantitative concentration measurement of corrosion products in the molten salt. Materials characterization revealed that both impurity species influence the dissolution of Cr from the alloy. The collective results from these analysis methods advance the understanding of the influence impurities have on materials corrosion.