The broad objective of this research is to develop anexciting new alloy class, that we have dubbednanostructured ferritic alloys (NFA). NFA, alloyed with12-14%Cr and small amounts of Ti and Y, have very highstatic tensile and creep strengths (up to temperatures inexcess of 800°C), excellent ductility and high corrosionoxidationresistance. NFA also promise unique resistanceto radiation damage, including high helium concentrationsin fusion reactor and accelerator based spallation neutronsources. The excellent properties of NFA primarily derivefrom a high concentration of 1-3 nm scale Y-Ti-O soluteclusters, with secondary contributions from a distributionof slightly larger (> 3 nm) Y_2Ti_2O_7 oxides. NFAs areprocessed by ball milling metallic elemental or alloypowders (Fe, Ti, Cr) with Y_2O_3, followed by hotconsolidation by HIPing or extrusion. Other hightemperature thermal-mechanical processing andfabrication steps, including solid-state joining, may followpowder consolidation.
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