I. Kap, M. Starostin, G. E. Shter and G. S. Grader
Cover: Corrosion resistance of 304, 316L, 310 SS and 680 nickel alloy was studied in concentrated ammonium nitrate-urea (ANU) solution. This solution provides the basis for development of a new alternative mono-fuel that can potentially reduce the harmful effects of fossil fuels combustion. The ANU solution is an aggressive medium, especially at high temperatures. Tests in ANU at 350 °C and 20 bar on SS 304, 316L and 680 nickel alloy showed that all are susceptible to uniform and pitting corrosion. An example of a pit in SS 304 is shown in the large cover picture. The pitting on SS 304 and 316 increased with addition of 5% sodium chloride to the ANU solution. Under these conditions corrosion attack was not found on 310 SS, as shown on the small insertion - making it a good candidate for ANU reactors.
More detailed information can be found in: I. Kap, M. Starostin, G. E. Shter, G. S. Grader; Corrosion of aluminium, stainless steels and AISI 680 nickel alloy in nitrogen-based fuels; Materials and Corrosion 2012, 63, 571.