Microstructure refinement and strengthening mechanisms of a 12Cr ODS steel processed by equal channel angular extrusion.

Highlights: [•] The first successful severe plastic deformation of 12Cr ODS steels. [•] Significantly refined and homogeneous microstructure in ODS steels. [•] Shear stress induced drastic variation of geometry of Y2O3 nanoparticles. [•] Strengthening arising primarily from grain refinement. [ABSTRACT FROM AUTHOR]