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 fr acture. At 800-1000 degrees C flow curves exhibited clearly defined pe aks followed by gradual softening which was greater at higher stresses . At 600 degrees C with (epsilon) over dot = 0.01 s(-1), deformation c urves 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 grai ns with little recovery. At 700-1000 degrees C, elongated grains conta in substructure which is mon developed at higher T and epsilon and low er (epsilon) over dot with no evidence of dynamic recrystallization. ( C) 1997 Elsevier Science S.A.