Experimental validation of numerical modeling of electrohydraulic forming using an al 5052-H34 sheet

Electrohydraulic forming (EHF) is a high strain rate process that uses an electric discharge in fluid. When electrical energy stored in a capacitor is discharged, two electrodes that are submerged in a fluid create a high-pressure shock wave that deforms a blank to a forming die. This study presents numerical results of EHF conducted in advance using LS-DYNA commercial software. The arbitrary Lagrange–Eulerian method was employed to create elements in the fluid region, and lagrangian mesh was used for the structural region. Numerical results showed that a pressure wave was created from the electrical energy in the capacitor, which led to the deformation of an aluminum alloy sheet kept in contact with the fluid surface into a die. It was also found that the maximum strain rate of the blank was approximately 3200 s−1. An EHF apparatus was also developed and a forming test carried out as a function of the amplitude of the input voltage using a capacitor with 32 kJ stored energy. A comparison between the bulge height of the blank from the experiment and that obtained via numerical simulation showed good agreement.

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