Decarburization of high-chromium melts by argon–oxygen plasma

Resumo

The treatment of Fe–Cr and Fe–Cr–Ni alloys by means of oxygen-bearing plasma is investigated in the laboratory, using a plasma furnace with a tungsten cathode and a water-cooled copper anode. That permits modeling of the processes in the contact spot of the plasma arc and the melt surface. The mathematical model developed describes the melt–plasma interaction. The kinetic parameters of the decarburization of high-chromium melt by argon–oxygen plasma are determined from experimental data. The results show that considerable decarburization of high-chromium melt is possible, with little loss of chromium, by treatment with plasma containing no more than 15–17% oxygen. Comparison shows that the model data and experimental results are in good agreement.