Electro-hydraulic forming process with electrodes that advance within a fluid chamber toward a workpiece

1. A method for electro-hydraulically forming a sheet metal part in an electro-hydraulic forming (EHF) machine comprising:

supplying a first volume of liquid to a chamber of the EHF machine;

placing the part that is in a first shape in the EHF machine between a one-sided forming die and a chamber that is then completely filled with a second volume of liquid to the part;

discharging an electrode in the chamber to form the part toward the forming die and form the part into a second shape;

supplying a third volume of liquid to a chamber;

advancing the electrode within the chamber toward the part; and

discharging the electrode in the chamber to form the part toward the forming die and form the part into a third shape.

2. The method of claim 1 further comprising forming the part into the first shape in a process selected from the group comprising:

mechanical press forming,

hydro-forming, and

electro-hydraulic forming.

3. The method of claim 1 further comprising in the first discharging step discharging a stored charge source across a gap between two spaced electrodes of a gap electrode EHF machine.

4. The method of claim 3 further comprising in the second discharging step, discharging a stored charge source across a gap between two spaced electrodes of the gap electrode EHF machine.

5. The method of claim 3 further comprising in the second discharging step, discharging a stored charge source across a wire electrode of a wire electrode EHF machine.

6. The method of claim 1 further comprising refilling the chamber after the discharging step and after the step of advancing the electrode.