The instrumentation of an industrial vacuum arc refining furnace (VAR process) has
allowed for the first time to visualize the electric arc during the remelting of a
zirconium alloy. This device, recording fast video observations in synchronization
with the high frequency voltage changes of the arc, has been applied to the study
of the behaviour of the arc and of the transfer mechanisms of the liquid metal to the
ingot. Results are given for current densities of about 10 to 20 A/cm2 and arc
lengths smaller than 6 cm.