Heating of steel by passing current through solid conductors and using the heat generated as a result of the conductors' inherent resistance to the flow of current. It can be applied through three methods :
1. The indirect method, in which the steel is heated by radiation and convection from resistors through which the current is passed.
2. The direct method in which the current is passed directly from a power source through the metal.
3. The induction method in which the current is induced in the steel by an induction coil connected to the power supply. 
Neither the indirect nor the direct method of resistance heating is practical for steel-making operations. However, the induction method is employed successfully in special steel-melting operations.
Resistance Heating
