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ElectroSlag Remelting (ESR) is widely used to produce high added value alloys for critical applications (aerospace industry, nuclear plants, etc.). In collaboration with Aubert & Duval, Institut Jean Lamour has been developing for several years a numerical transient model of an ESR heat. In the previous version of the model, the crucible was assumed to be perfectly electrically insulated from the electrode-slag-ingot system. However, this assumption must be challenged: the solidified slag skin at the slag/mold and ingot/mold interfaces may actually allow a fraction of the melting current to reach the crucible. In this paper, an evolution of the model is presented that enabled us to take into account the possibility of mold current. The simulation results were compared with actual experimental data. Sensitivity studies showed the influence of slag properties and operating parameters on the final quality of the ingot. Results highlighted that even a weakly conductive solidified slag skin at the inner surface of the model can be responsible for a non-negligible amount of current circulating between the slag and crucible, which modifies the fluid flow, heat transfer and solidification of both the slag phase and the metallic ingot.

A model for the evolution of microstructures and flow stress during the tempering of low alloyed steels has been developed. The competitive precipitations of ε carbide and cementite are simulated. The results are used to calculate the flow stress of the tempered martensite by a thermo-elasto-viscoplastic law that takes into account solid solution, dislocation and precipitation hardenings. The model is applied to a 80MnCr5 steel and the calculated results are compared with the experimental ones.