Abstract
Electromagnetic forming is a typical method of high energy rate forming. This is the newest-and also one of the most spectacular-of the H.E.R.F. techniques along with spark discharge forming.
Electrical energy stored in a capacitor bank is discharged rapidly through a coil, establishing a changing high-intensity magnetic field. The metal plate in the magnetic field is flyed up by the magnetic force.
Magnitude of the magnetic force is estimated by measuring by maximum flying height.
In this experiment disk materials are copper, Aluminum, Magnesium, Zinc, Cadmium, Iron and Tin.
The following experimental results have been obtained.
1) Maximum flying height is depend on resistance of disk material, increasing resistance decreases maximum height.
2) Maximum value of magnetic force exists being due to thickness of disk and frequency of discharging current.
The experimental formula is introduced as following.
t=kf-0.9
Where t is the thickness of disk, f is the frequency of the discharging current and k is constant.
Relationship between resistance of these materials and forming difficulty of each metals is shown in table 1.
