Corrosion Behavior of Inconel 690 & 693 in an Iron Phosphate Melt
The corrosion resistance of Tnconel 690 and 693 coupons submerged in an iron phosphate melt has been investigated. After 155 days in an iron phosphate melt at 1050°C, which contained 30wt% of a simulated low activity waste (LAW at Hanford), the weight loss of Inconel 690 and 693 was 14% and 8%, respectively. The overall corrosion rate, calculated from the initial and final dimensions of each coupon, was 1.3 and 0.7 μm/day for the Inconel 690 and 693, respectively. Scanning electron microscopy and X-ray diffraction of the submerged Inconel coupons after 155 days in the iron phosphate melt showed that an altered surface layer had formed which was depleted in nickel and consisted of a (Fe, Cr)2O3 solid solution. This altered layer appears to be chemically protective as indicated by the gradual reduction in weight loss which occurred with time in the iron phosphate melt. Inconel 693 appears to be a better candidate to use as an electrode in iron phosphate melts since its corrosion rate and weight loss was only about one half that of Inconel 690.
D. Zhu et al., "Corrosion Behavior of Inconel 690 & 693 in an Iron Phosphate Melt," Journal of Nuclear Materials, vol. 336, no. 1, pp. 47-53, Elsevier, Jan 2005.
The definitive version is available at http://dx.doi.org/10.1016/j.jnucmat.2004.08.010
Mining and Nuclear Engineering
Materials Science and Engineering
Keywords and Phrases
Computer simulation; Corrosion resistance; Scanning electron microscopy; Solid solutions; Corrosion behavior; Inconel 690; Weight loss; Iron compounds
International Standard Serial Number (ISSN)
Article - Journal
© 2005 Elsevier, All rights reserved.