Corrosion and carburization behavior of Al-rich surface layer on Ni-base alloy in supercritical-carbon dioxide environment

Effect of pressure on the corrosion and carburization behavior of chromia-forming heat-resistant alloys in high-temperature carbon dioxide environments

“…Meanwhile, peaks for the Al-rich phase were not observed in the XRD analysis even for Alloy 800HT. This could be due to either an insufficient amount or the semi-crystalline structure of Al-rich oxide formed at approximately 600 • C [12,13]. The extensive formation of TiO 2 ridges on top of Cr 2 O 3 was also reported for Alloy 617 with a smaller amount of Ti but with a large amount of Al at 900 • C in helium environment [26].…”

“…The corrosion and carburization behavior of several candidate materials has been studied in S-CO 2 environments at various temperatures (500-750 • C) and pressures (20)(21)(22)(23)(24)(25), conditions relevant to SFR and advanced ultra-supercritical (A-USC) fossil plant operation [12][13][14][15][16][17][18][19][20][21][22][23][24]. According to those studies, for Fe-based alloys on which Fe-and Cr-rich oxides were formed, carburization was observed at the oxide layer/matrix interface and underneath the oxide layer during S-CO 2 exposure at 550-650 • C [6,15,18].…”

A Tracer Study on sCO2 Corrosion with Multiple Oxygen-Bearing Impurities

“…Alumina scales have been found to withstand carburization better than chromia scales [18,19]. However, the alumina scale is impermeable to carbon only when it is continuous and consists of α-alumina [20]. Interestingly, Ni-based alloys appear to withstand carburization better than Fe-based alloys, most likely due to the reduced carbon solubility and Cr carbide stability in Ni-based alloys [14,21].…”

High-temperature corrosion resistance of nickel-base alloy 617 in supercritical carbon dioxide environment

“…After 1000 h, the carbon content was slightly higher than that of Inconel 617 exposed to supercritical carbon dioxide for 250 h, as shown in figure 5(b). The penetrated depth of the carbon was larger due to the inward diffusion of carbon [12,18]. What's more, The carbon was detected at the oxide surface by the Raman analysis in figure 6.…”

“…David et al studied that the corrosion behavior of Fe-Cr-X alloys in the various corrosive environments containing CO 2 and obtained the corrosion kinetics and mechanism [6,16,17]. Lee researched the corrosion behaviors of several high Cr alloys in high-temperature supercritical carbon dioxide at different pressures [4,18,19]. Inconel 617 has an excellent strength property and poses a great corrosion resistance in high-temperature supercritical fluids.…”