Tensile and creep properties of an oxide dispersion- strengthened ferritic steel

The tensile and creep properties of two oxide dispersion-strengthened (ODS) steels with nominal compositions of Fe-12Cr-0.25Y(2)O(3) (designated 12Y1) and Fe-12Cr-2.5W-0.4Ti-0.25Y(2)O(3), (12YWT) were investigated. Optical microscopy, transmission electron microscopy, and atom probe field ion microscopy studies indicated that the 12YWT contained a high density of extremely fine Y-Ti-O clusters, compared to the much larger oxide particles in the 12Y1. The fine dispersion of particles gave the 12YWT better tensile and creep properties compared to commercial ODS alloys and ferritic/martensitic steels that would be replaced by the new ODS steel. (C) 2002 Elsevier Science B.V. All rights reserved.