Deformation Optimization for Inconel718 Superalloy Sheet Hydroforming Numerically and Experimentally

Abstract

For deep cylindrical cups with a large height-diameter ratio, it is difficult to be hydroformed in one stroke. Reverse deep drawing is necessary after deep drawing. Deformation optimization was performed to achieve a large drawing ratio and uniform thickness. An inconel718 superalloy deep cup was investigated numerically and experimentally. For a larger total drawing ratio 3.1, different deformations were analyzed for hydromechanical deep drawing and reverse hydromechanical deep drawing under the condition of different loading paths. Effects of deformations were discussed on the thickness. Typical defects were analyzed for different deformation. Optimal deformation was determined for hydromechanical deep drawing and reverse hydromechanical deep drawing. The results show that a superalloy cup with a total drawing ratio 3.1 could be successfully hydroformed, and the minimum thickness is 0.65 mm.