Warm hydro-mechanical deep drawing of 18-8 stainless steel

Stainless steel parts with large relative height (H/d) for aerospace use usually need a long conventional stamping process, during which season cracking is easy to occur. Warm hydro-mechanical deep drawing, a new forming process, based on warm mechanics property of SUS304 stainless steel is therefore proposed. Experiments show that the formability is improved at a higher temperature above room temperature, and the process is easy to perform, the limited drawing ratio of the cylindrical cup is effectively raised at 90°C, and the limited drawing ratio 3.3 is obtained beyond 2.0 with conventional deep drawing, avoiding the defects such as adhesion to the mould. As the residual stress decreases, the probability of season cracking is reduced.