Hot working and microstructure in 409 ferritic steel

After continuous casting, homogenization and hot working, 409 ferritic stainless steel was deformed by torsion to different strains up to fracture. At 800-1000 degrees C flow curves exhibited clearly defined peaks followed by gradual softening which was greater at higher stresses. At 600 degrees C with (epsilon) over dot = 0.01 s(-1), deformation curves show only strengthening to failure but a peak is present at 700 degrees C. At 900-1000 degrees C, flow curves approach a steady state. The optical microstructure at 600 degrees C consists of deformed grains with little recovery. At 700-1000 degrees C, elongated grains contain substructure which is mon developed at higher T and epsilon and lower (epsilon) over dot with no evidence of dynamic recrystallization. (C) 1997 Elsevier Science S.A.