What Is Electromagnetic Forming?

Electromagnetic forming is a process where high levels of electrical energy generate an opposing magnetic field in a metal object that is then formed to the shape of the stronger magnetic field in the work coil generator. It is most often used to form highly conductive metals such as copper and aluminum, but can also be used to form steel parts or to join together conducting and non-conducting materials, such as copper and a ceramic. Since the process has such high energy demands and is subject to inertia effects that necessitate precise control, it is generally only used to shrink or expand metal tubing. High velocity forming using magnetic fields also has applications in research into forming sheet metal, and metal-ceramic composites used in superconducters and other components.

The process of electromagnetic forming, or EM forming, has been around since early research into it was conducted by Pyotr Kapitza, a Russian physicist who won the Nobel Prize in physics in 1978. He began researching the process, also known as magneforming, in 1924 by using lead acid batteries to generate a magnetic field up to 500,000 Gauss in strength for three milliseconds of duration. Gauss is a measure of the strength of a magnetic field, and, by comparison, Earth's magnetic field ranges from 0.3 to 0.6 Gauss. Pyotr's research into producing magnetic fields over 300,000 Gauss in strength resulted in violent explosions, and later attempts into electromagnetic forming switched to the rapid discharge of high voltage capacitor banks.

By the late 1950s, electromagnetic forming had industrial patents placed on the process and tubular parts were being shaped by it in the early 1960s. The aerospace industry saw a use for the method, as it can form tubing that is extremely uniform. All of the major commercial aerospace manufacturing corporations around the globe had their own magneforming equipment by the 1970s and were refining the process into the 1980s.

The development of electromagnetic forming technology has remained largely secret, as it has applications in thermonuclear fusion research. A practical fusion reactor would produce no nuclear waste, have no chance of melting down, and could be run on deuterium fuel extracted from seawater, so many nations are competing to be the first to perfect the process. One of the most fundamental problems with fusion research is how to contain the fusion reaction, and the magnetic fields being researched in electromagnetic forming may be the solution to the problem.