A method using electropulsing to separate inclusions from molten steel is developed, based on the differences in electrical properties between the inclusions and liquid metal. The inclusions have different electrical resistivity from that of the liquid steel and hence being expelled to the surface of the metal by electropulsing. In comparison with the as-solidified untreated steel, the size of the inclusion is significantly larger at the surface of the molten steel due to the enhanced agglomeration. Moreover, the technique is efficient in eliminating particles smaller than 20 µm.

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Precipitation takes place when the austenite stainless steel is heated to a high temperature. This is found significantly different when the electropulsing is implemented during the heat treatment. Considerable less number density and much smaller particle size of precipitates are formed in the sample treated with electropulsing. Electropulsing helps to dissolve precipitates.The effect is not due to Ohm heat. Instead, it is attributed to the electric-current-induced change of thermodynamic sequences of the phases and the electric-current-accelerated mass diffusion.

Oriented sulphides parallel to the electric current direction have been experimentally observed when a pulsed electric current is passed through medium carbon steels with MnS inclusions. Two different configurations of sulphides occur after the application of the electric current: namely, oriented elongated ellipsoidal particles and oriented chain-like particles composed of two or three small spherical sulphides. Theoretical analysis indicates that this phenomenon is associated with minimisation of the electrical resistance of the material.

Thermal crack initiation and pitting corrosion are frequently caused by the formation of the secondary phases such as sigma phase, delta-ferrite phase, carbides and secondary austenite phase in steel. Traditionally, heat treatment is used to minimize these detrimental effects of the secondary phases. In this study, we have applied pulse to the 316L stainless steel and observed the considerable effects. In comparison to the heat treatment, the electropulsing can effectively suppress the precipitation of the secondary phases in a temperature range (1161 K–1173 K). Austenite grain size becomes larger under electropulsing compared to the heat treatment at annealing temperatures due to enhanced interface migration. The kinetic and thermodynamic aspects of electropulsing can be used to explain the effects of electropulsing on the evolution of microstructure for 316L stainless steel.