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Until recently a laboratory curiosity, diamagnetism has entered the commercial world as part of a hybrid levitation system in which a diamagnetic force provides the necessary control stability and permanent magnets supply the lift.
Imagine two surfaces of a noncontact bearing, less than 1 mm apart and sliding effortlessly past each other without touching. No lubrication is required to keep the surfaces separate or protect them from wear. In fact, these surfaces could as well be in a vacuum with virtually nothing between them but a few gas molecules. Frictional forces and heat generation are nonexistent in a noncontact bearing. Since there are no contacting surfaces, lines, or points, the motion is not only effortless but also clean-no particles are released to contaminate the operating environment. The life of such a bearing could he infinite. Bearing failures and normal maintenance could be eliminated, limiting the cost of ownership to only the initial component price.
Now imagine this technology applied to your critical bearing needs. The bearings would have no parts to wear out, no lubrication to contaminate clean environments, and no friction to overcome because the surfaces are held apart by magnetic lines of force, or magnetically levitated.
Magnetic levitation is not new to the motion industry. In fact, many articles have been published about its use in transportation, particularly in monorails, and in levitating displays. Magnetic bearings have been used in pumps, compressors, steam turbines, gas turbines, motors, and centrifuges, but these complex applications require electromagnets, sensors, and control systems. Moreover, active levitation systems are costly and function only when energy is supplied. In this article we discuss diamagnetism, a source of simple, straightforward levitation that requires no energy or control system and which can last virtually forever.