Abstract: In this paper, the recrystallization behavior of steel 9Gr- 1Mo - V-Wb - N at high temperature was studied using Gleeble - 1500 thermalmechanical simulator.The critical conditions of occurrence of dy- namic recrystallization during hot deformation were obtained,and by means of double hit testing with an inter -hit time, the metabynamic recrystallization between rolling passes and its effect factors were also imitated.Additionally,the deformation activation energy of T91 steel,the relationship between critical stress,strain, temperature, and strain rate were regressed respectively, the results were sati- sfied.

Key words: ferritic stainless steel, recovery, recrystallization