Experimental study and finite element simulation of the effect of cone angle on drawing ratio and thickness distribution in hydroforming of conical-cylindrical cups

Conical parts have a lot of usage in aerospace and special industries. These parts usually formed by spinning, explosive forming, multistage deep drawing. Due to their bad forming condition in conventional methods, some new forming methods have been explored to increase the drawing ratio, hydroforming is one of the more effective methods. In this study hydrodynamic deep drawing assisted by radial pressure is used to form the conical‐cylindrical parts. Commercially pure copper is used in this research. The process is initially simulated using the FEM solver ABAQUS. Experiments have been conducted with different punch geometries. The punch geometries consist of conical and cylindrical wall segments. This paper examines the effect of cone angle on drawing ratio and thickness distribution of conical cups. Using the measurements of thickness variations on the cup wall, the quality of the cups drawn has been evaluated. The results of the study demonstrated that increasing the cone angle has a important effect on drawing ratio and cause uniform thickness distribution. Also it was concluded that the conical‐cylindrical parts had two critical regions at contact area of punch tip with the blank and the transition zone between the conical and cylindrical portions that variation at cone angle affected these regions and resulted to variation of these areas. It was proved that the results from the experiment and the simulation were in a reasonable agreement.