A device including at least one transformer with primer/seconder coil
ratio more than one and including a control unit used to control timing
and magnetute of the primer current is employed to heat a metal workpiece
to be subjected a subsequent forming operation. An homopolar DC generator
can also be used as current source for current heating preparing
workpiece for forming operation. Subsequent heating, forming and cooling
processes of the metal workpiece are carried out in a controlled manner
by a central synchronization unit. This process can be applicated in hot
metal bulk forging, sheet forming and hot tube blowforming.