The corrosion behavior of various high temperature corrosion-resistant alloy systems in sCO2 is being investigated. The alloys are compared and discussed based on the microstructure-mechanical property relationships examined, with consideration of their different metallurgical makeup. An autoclave with a testing capacity of 1 [L] was designed to operate at temperatures and pressures up to 850 [C] and 26.4 [MPa], respectively. Test samples were exposed to for up to 1500 hours. Examined alloys include Haynes Alloys 214, HR 224, 230, 282, 617, 625, 718, 740, 800H; and Stainless Steels 316 and 347. Characterization that has been employed includes incremental weight change and corrosion rate, microbalance measurements; oxide thickness, SEM and microbalance; surface morphology, optical microscopy and SEM; cross-sectional oxide morphology, TEM; chemistry, XPS EDX WDX; and phase identification, XRD and TEM.