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The purpose of this work is to quantify the effects of dissolved zinc cations on corrosion and release rates from a pre-filmed Alloy 690 steam generator tubing material that was subsequently exposed to water containing zinc. The corrosion tests were performed in circulating 2 ppm Li and 1000 ppm B water without and with 60 ppb zinc at 330 °C. Gravimetric analyses and oxide characterization revealed that the corrosion rates, release rates, and oxide thicknesses decreased by subsequent exposure of the pre-filmed Alloy 690 to zinc. These benefits are attributed to the formation of a chromium-rich inner oxide layer incorporating zinc. [ABSTRACT FROM AUTHOR]

The harsh atmosphere of the sulfur–iodine process used for producing hydrogen requires better corrosion resistance and mechanical properties than are possible to obtain with pure tantalum. Ta–W alloy is superior to pure tantalum but is difficult to alloy due to its high melting temperature. In this study, substrate samples were coated with Ta–W (Ta–7W, Ta–4W and Ta–1W) using the Multi-Anode Reactive alloy Coating (MARC) process in molten salt (LiF–NaF–K 2 TaF 7 ), with varying distances between cathode and anode. In the case of Ta–4W, a corrosion rate of less than 0.011 mm/year was attained in hydriodic acid at 160 °C, and thickness uniformity was 80.3 ± 2.15 μm. Also, the resulting coated films had hardnesses up to 12.9% stronger than pure tantalum coated film. The alloy coating films also contributed to significant enhancement of corrosion resistance. [ABSTRACT FROM AUTHOR]

Abstract: Hot corrosion studies were performed on superalloy specimens. The IN713LC superalloy were sprayed with an aluminized NiCrAlY-bond coat and then with an yttria–zirconia top coat. The bare superalloy reveals an obvious weight loss due to spalling of the scales by the rapid scale growth and thermal stress. The top coatings showed a much better hot corrosion resistance in the presence of LiCl–3 wt.% Li2O molten salt when compared with those of the bare superalloy and the aluminized bond coatings. These coatings have been found to be beneficial for increasing hot corrosion resistance of structural materials for lithium molten salts. [Copyright &y& Elsevier]

• High-temperature corrosion mechanism of Kanthal alloy in molten silver is proposed. • The corrosion behavior showed that the gas region was more severe than the liquid region. • There were some entrapped porosities in the gas region, but not in the liquid region. • The corrosion products were Al 2 O 3 and FeAl 2 O 4 in gas, whereas only Al 2 O 3 appeared in liquid region. The high-temperature corrosion behaviors of Kanthal alloy for an anode current-collector were investigated at 1150 °C in molten silver under an oxidizing atmosphere. The hot corrosion products of Kanthal alloy in the gas section were Al 2 O 3 and Al 2 O 3 and FeAl 2 O 4 obtained after 1 d and 3, 5, and 7 d, respectively. Contrarily, only Al 2 O 3 was identified in the liquid silver section. Isolated patches were observed beneath the outer oxide layer in the gas section, whereas there was no evidence of these in the liquid silver section, and a cohesive Ag-rich layer beneath the oxide layer was shown to retard the corrosion by acting as an effective barrier. [ABSTRACT FROM AUTHOR]