Abstract. Electromagnetic forming is a high-speed sheet metal
forming technique to form metallic sheets by applying magnetic forces. In comparison to the conventional sheet metal forming process, electromagnetic
forming is a process with an extremely high velocity and strain rate, which can be effectively used for the forming of certain difficult-to-form metals.
During electromagnetic forming, it is important to recognise the effects of
process parameters on the deformation and sheet thickness variation of the
sheet metal. This research focuses on the development of a numerical model
for aluminium alloy (AA6061-T6) to analyse the effects of three process
parameters, namely voltage, sheet thickness and number turns of the coils, on the deformation and thickness variation of the sheet. A two-dimensional fully coupled finite-element (FE) model consisting of an electrical circuit, magnetic field and solid mechanics was developed and used to determine the effect of
changing magnetic flux and system inductance on sheet deformation.
Experiment validation of the results was performed on a 28 KJ electromagnetic forming system. The Taguchi orthogonal array approach was used
for the design of experiments using the three input parameters (voltage,
sheet thickness and number of turns of the coil). The maximum error between
numerical and experimental values for sheet thickness variation was observed
to be 4.9 %. Analysis of variance (ANOVA) was performed on the experimental results. Applied voltage and sheet thickness were the
significant parameters, while the number of turns of the coil had an insignificant effect on sheet deformation. The contribution ratio of voltage
and sheet thickness was 46.21 % and 45.12 % respectively. The sheet
deformation from simulations was found to be in good agreement with the
experimental results.
Numerical and experimental investigation of the effect of process parameters on sheet deformation during the electromagnetic forming of AA6061-T6 alloy