Electromagnetic Suspension of a Molten Zone

A new method of suspending a molten zone is as follows: clamp a horizontal cylindrical ingot at both ends; apply a horizontal magnetic field normal to the ingot where the zone is to be suspended; and pass a direct current through the ingot, creating an upward force equal and opposite to the gravitational force, thereby permitting the zone to be melted and suspended. It is shown theoretically that such a zone will be stable in a uniform magnetic field if its length‐to‐diameter ratio is less than π and if its length is less than 0.17(γ/ρ)½, where γ and ρ denote surface tension and density, respectively, in cgs units. Some experimental results and practical considerations are discussed.