Manufacturing of Shaped Forms from Stainless Steels with Superplastic Forming

摘要

Shaped forms have been manufactured with superplastic forming from austenitic (EN 1.4318) and microduplex stainless steels (EN 1.4362). The aim was to find suitable process parameters for manufacturing of the prototypes. Based on the results of hot tensile tests and cone cup tests, the forming temperatures used were 800 and 960°C for EN 1.4318 and 960°C for EN 1.4362. The possibility to lower forming temperature by using EN 1.4318 may offer savings in manufacturing costs. However, longer forming times are needed for EN 1.4318 than for EN 1.4362, which increase the process costs for EN 1.4318. Altogether, further developments in the thermomechanical processing of EN 1.4318 are needed in order to make it more competitive as compared with duplex stainless steels.