Alloys SS316 and Hastelloy-C276 in Supercritical CO2 at High Temperature

作者：Olivares R I^*; Young D J; Marvig P; Stein W

来源：Oxidation of Metals, 2015, 84(5-6): 585-606.

DOI：10.1007/s11085-015-9589-5

• Oxidation
• High-temperature corrosion
• Supercritical CO2
• Stainless steel 316
• Hastelloy-C276

Commercially available high pressure tubing materials SS316 and Hastelloy-C276, containing a similar chromium content about 17 wt%, were internally pressurised by flowing supercritical CO2 at 20 MPa and heated externally, to 650 A degrees C in the case of SS316, and 650-750 A degrees C in the case of Hastelloy-C276. The stainless steel was found to be corroded by both external oxidation and internal carburisation. The external oxide was initially protective Cr-rich oxide, which was subsequently disrupted by faster growing Fe-rich oxide nodules, leading to loss of protection. In the case of Hastelloy-C276, the corrosion product was principally protective chromium oxide scale, although somewhat thicker regions of the same oxide developed at the site of micro-cracks in the metal surface. Very little carburisation of this alloy was observed up to at least 1000 h exposure. Differences in scaling behaviour are discussed in terms of chromium depletion through internal carbide precipitation.

• 出版日期2015-12