Evaporation Behaviour of Elements during the Large Section Consumable Electrode VAR Process of Alloy A-286

摘要

The remelted characteristics of the large section consumable electrode and the Mn distribution in various regions at the electrode tip during the VAR process of alloy A-286 were studied. It was found that Mn mainly evaporized in the forming period of droplets at the electrode tip and suggested that Mn evaporation be controlled by the transfer rate of Mn atoms in the liquid-solid two phase region. The compositions of electrodes, remelted ingots and condensate layers on the water-cooled crucible wall were analyzed. The results indicated that Mn, Cr, Fe and Ni evaporized simultaneously but the Cr, Fe and Ni contents in the remelted ingot were almost the same as those in the consumable electrode. The Mn content of the remelted ingot can be controlled by controlling the Mn content and the remelted rate of the consumable electrode in terms of a kinetics equation derived by authors.