In their elegant laboratories near La Jolla, Calif., General Dynamics
scientists are doggedly attacking a difficult problem: how to extract
controlled power from hydrogen fusion. The pay off for their work is
hidden in the future, but the powerful magnetic fields they have
built to hold reacting hydrogen gas at 100 million degrees has
already yielded a valuable practical “fallout.” Those same
magnetic forces used on a smaller scale have proved remarkably
versatile for shaping metal.Swift Action. At a Detroit meeting of the American Society of Tool and
Manufacturing Engineers, engineers from General Dynamics' General
Atomics Division demonstrated how the principle works in practice.
Magneform — a tool little larger than a home washing machine and using
no more current than an electric range — has no moving parts at all.
Its essential part is a coil of heavy wire that can take var ious
shapes, including a cylinder, a doughnut or a flat disk. When a
massive electric current from a capacitor is shot suddenly through a coil,
it creates an intense magnetic field in the space around it. If a
piece of metal is near by, the magnetism starts currents flowing in the
metal. These currents are surrounded by their own magnetism, and
repulsion between the two fields drives the metal violently away from
the coil. The action is over in microseconds, but it is powerful
enough to push rigid metal into almost any shape.The different coils do different jobs. When the end of a metal tube is
inserted into the doughnut-shaped coil, it can be shrunk tightly around
any insert such as a plug or a threaded fitting. To expand a metal
tube, a cylindrical coil is pushed inside it. A flick of the switch,
and the tube expands to bind itself solidly to whatever surrounds it.
To stamp a flat piece of metal with a pattern, a trademark of elaborate
lettering, the metal is placed between a flat coil and a die. When the
coil is activated, the opposing magnetic field in the sheet shoves it
away from the coil and presses it into the die.Gentle Handling. Magneform is already doing many useful jobs: aluminum
and copper are being joined to porcelain insulators for outdoor wiring;
the metal bands around artillery shells are being fitted quickly
without any fuss. The auto industry is using Magneform to produce
ball-joint and seal assemblies for front suspensions. Magne-form's
principal advantage over welding, pressing or stamping is its ability
to shape metals without the rough handling that such operations
ordinarily require. Automated assembly-line operation can be managed
easily, and Magneform men are already looking toward the day when most
subsidiary parts of an auto engine—carburetors, fuel pumps, etc.—are
shaped and stuck together by Magneform.
