FORMABILITY OF AUSTENITIC STAINLESS STEEL 316 SHEET IN DYNAMIC STRAIN AGING REGIME

Abstract

Dynamic strain aging region for austenitic stainless steel 316 was investigated from room temperature to 650°C at constant strain rates of 1x10-2, 1x10-3 and 1x10-4 sec-1. Characteristics indicators of serrated plastic flow were observed in the temperature range of 400°C to 600°C at these strain rates. Strain rate sensitivity of the material is found to be negative in this region. Study of fracture surface of tensile test specimen by scanning electron microscope revealed that ductility in this region decreased. The limiting drawing ratio of sheet metal is the indicator of formability in deep drawing. LDR of the sheet metal was estimated by performing the deep drawing of different diameter blanks in finite element simulation software LS-DYNA in DSA temperature region. It was observed that in DSA region, formability of sheet metal decreased. These simulations are validated and compared with experimental results.