Formability of metastable austenitic stainless steel sheets. I. Experimental

Formability of sheets of a low nickel (2.5 wt.% Ni) metastable austenitic stainless steel developed by some members of the Indian Stainless Steel Development Association has been examined with a view to identifying similarities and differences in comparison with the formability of AISI 304 stainless steel sheet (used as benchmark). The formability of the 0.42 mm thick 2.5% Ni stainless steel was as good as that of the 0.50 mm thick AISI 304 under conditions of drawing. But the formability was somewhat inferior in the regions where stretch forming dominated because of a lower rate of work hardening and consequently a smaller value for the strain hardening exponent. Due to higher normal anisotropy being present in sheets of lower thickness, sheets of higher thickness showed superior formability compared with sheets of lower thickness while the converse was the case in the deep drawing region in the stretch forming region