LEVITATION AND HEATING OF METALLIC BALL I N COLD CRUCIBLE SIMULTANEOUSLY SUPPLIED WITH 2 FREQUENCIES

The levitation forces working toward the metallic ball in the cold cru cible and the temperature rise of the metallic ball were measured unde r supplying two different frequencies (3kHz and 30kHz) simultaneously with the object of the optimum operation of the cold crucible type lev itation melting. The results obtained are as follows. (1) The levitati on forces supplied by two frequencies take additional values of 3kHz a nd 30kHz which are supplied independently. (2) The behavior of tempera ture rise of the metallic ball in the case of supplying two frequencie s are almost equivalent to additive behavior of 3kHz and 30kHz power s upplying independently. A new control technique for levitation melting where rather lower frequency is mainly allotted for levitation and hi gher frequency is mainly allotted for beating has been suggested by th e above stated results.