Abstract
Contact resistance between cathode block and cast iron plays an important role for the ohmic resistance of the cathode system and hence for the cathode voltage drop (CVD). Investigations of the standard dove-tail cathode slot design showed poor electrical contact in the bottom of the slot and small contact area on the cathode wings. Different thermo-mechanical properties of carbon cathode block, cast iron, and steel collector bar resulted in displacements relative to each other after rodding, during cooling and handling. To mitigate this effect without changing materials or procedures, different slot geometries were modeled with respect to preheating and casting. By introducing anchoring grooves for the cast iron at the bottom corners of the slot, bottom contact was achieved: Lab tests proved that voltage drop between cathode slot bottom and cast iron decreased significantly. Subsequent field trials showed a CVD reduction of 20 mV.
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Friedrich, R. et al. (2017). Minimizing Cathode Voltage Drop by Optimizing Cathode Slot Design. In: Ratvik, A. (eds) Light Metals 2017. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-319-51541-0_86
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DOI: https://doi.org/10.1007/978-3-319-51541-0_86
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