Electromagnetic forming is a kind of high-speed forming technology

which uses coils to generate pulse electromagnetic force to drive metal deformation.

the coils also bear huge magnetic stress. Especially with the improvement of discharge parameters and the use of combined coils

multiple coils have magnetic coupling in space and sequential control in circuit

which greatly increases the risk of stress damage. Therefore

this paper analyzes the stress state and failure condition of the combined coil under high parameters by experiment and simulation. The results show that the stress state of the combined coil is more complicated and extreme

and the coupling of the coil worsens the stress in local areas

and the axial reinforcement material breaks at a lower discharge voltage than the radial one. At the same time

the combined coil should be fully stress-checked during design.