Levitation and Heating of Metallic Ball in Cold Crucible Simultaneously Supplied with Two Frequencies

Abstract

The levitation forces working toward the metallic ball in the cold crucible and the temperature rise of the metallic ball were measured under supplying two different frequencies (3kHz and 30kHz) simultaneously with the object of the optimum operation of the cold crucible type levitation melting. The results obtained are as follows.
(1) The levitation forces supplied by two frequencies take additional values of 3kHz and 30kHz which are supplied independently.
(2) The behavior of temperature rise of the metallic ball in the case of supplying two frequencies are almost equivalent to additive behavior of 3kHz and 30kHz power supplying independently.
A new control technique for levitation melting where rather lower frequency is mainly allotted for levitation and higher frequency is mainly allotted for heating has been suggested by the above stated results.