Abstract:The tensile creep behavior of Y?O?-dispersion-strengthened tungsten (W-Y?O?) alloys prepared via powder metallurgy and high-temperature rotary swaging was investigated at temperatures ranging from 1400 to 1600°C under pressures of 150 to 180 MPa. Changes in grain structure, second-phase particles, and dislocations before and after creep were analyzed using scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM).Experimental results indicate that the creep performance of rotary-forged W-Y?O? alloys surpasses that of rolled pure tungsten, with a steady-state creep rate ranging from 8.22×10e-7 to 1.76×10e-4—two orders of magnitude lower than rolled pure tungsten. The superior creep performance of rotary-forged W-Y?O? primarily stems from the pinning of grain boundaries and dislocation motion by nanoscale and submicron-sized Y?O? particles, coupled with the suppression of diffusion creep due to thelarger grain aspect ratio.As temperature and creep stress increase, the agglomeration pinning effect of second-phase particles weakens, reducing the grain aspect ratio. The proportion of creep mechanisms dominated by grain boundary slip due to atomic diffusion and recrystallization gradually increases. However, dislocation motion control remains the primary mechanism in the W-Y?O? matri