Annealing behavior of 12-Cr based mechanical alloyed oxide dispersion strengthened ferritic alloys

12 wt.% Cr-ODS ferritic alloys were fabricated by mechanical alloying combined with hipping under different sintering pressure and then forging deformation work. The microstructures of the hipped and forged samples after annealing at different temperatures were investigated and compared. No obvious recrystallization occurred even at an annealing temperature of 1100 °C, both for as-hipped and as-forged materials. When hipping under high pressure (200 MPa), the ODS material is very dense, and almost no cavities could be found after annealing at high temperature. While when hipping under low pressure (70 MPa), obvious pores could be found for this material after forging, the pores assembled and formed big cavities up to ∼10 μm after annealing at temperature of 1300 °C.