Chromium Alloying in Steel during Electroslag Refining by Cr ₂ O ₃ Addition to Slag

The electroslag refining (ESR) process is used to produce high‐quality alloys for critical applications. Chemical reactions between steel and slag during ESR have been studied experimentally and with the help of kinetic models. However, there is limited work on alloying during the ESR process. This work reports chromium alloying of mild steel during the ESR process. Chromium alloying in mild steel, up to 2.1 wt%, is achieved by adding Cr 2 O 3 to the slag using different means under laboratory conditions. The mechanism of Cr 2 O 3 reduction and loss of aluminum during ESR are studied with the help of a kinetic model developed using the macro feature in FactSage. The calculation suggests that the major contribution to this alloying is due to the reaction at the melt pool–slag interface. Further, the model results also show that the oxygen pickup during the open‐air ESR process causes a loss of aluminum. However, it does not affect the rate of chromium pickup during the process.