The incorporation of a primary surface recuperator is one method for significantly improving the energy efficiency of a microturbine. The goal of this work is to employ laboratory testing of foil material (≈ 75-125μm or 3-5 mil thickness) to select alloys for higher temperature (750°−1000°C, 1400-1800°F) recuperator performance based on creep strength and corrosion resistance. Alloys of interest are high-Cr, Ni-base superalloys such as alloy 625 and aluminum-containing alloys such as Haynes alloy 214 and Plansee alloy PM2000, which is an oxide-dispersed FeCrAl. The interest in the latter two alloys is based on their corrosion resistance. Particularly in exhaust gas environments, chromia surface oxides are not sufficiently protective at high temperatures to achieve desired lifetimes. The formation of a slow-growing external alumina scale confers exceptional corrosion resistance for this application.

This content is only available via PDF.
You do not currently have access to this content.