Enhanced Strength of a 14Cr ODS Steel through Y Addition Fabricated Via PM Without Mechanical Alloying

Abstract

Oxide dispersion strengthened (ODS) ferritic steels are promising materials for Gen IV nuclear reactors owning to their excellent performance in extremely harsh environment. High number density of nano oxide particles within matrix was important reason for its excellent performance. Oxides could be introduced into matrix via the Powder Metallurgy-Hot Isostatic Pressing (PM-HIP). However, effect of oxide forming element on the microstructure and precipitates is not clear. In this study, the 14 Cr ODS steel with and without Y were prepared based on O-containing precursor powders fabricated without mechanical. SEM and TEM were carried out to analysis the microstructure of precursor powder and as-HIPed alloys, tensile properties of the as-HIPed alloys were tested at elevated temperatures as well. Finally, the evolution mechanism of Y element at different stage and its influence on tensile strength were discussed in detail.