Determination of the Air-Gap Distribution at the Cast Iron to Carbon Cathode Interface Using a 3D Scanning Approach

The electrical resistance of the cathode assemblyCathode assembly contributes to 8% of the 4.2 V operating voltage of a 400 kA reduction cellCell, and electrical contact resistanceContact resistance (ECR) at the cast ironIron-carbon cathodeCathode interface causes most of this resistance. Since ECR depends on temperature and contact pressure at the interface, it indirectly depends on initial air-gap distribution and its evolution during the operationOperation. Accurate determination of this important parameter remains a challenge even today. In this paper, a 3D scanning3D Scanning approach is proposed to measure the initial air-gap distribution at the cast ironIron-carbon cathodeCathode interface of an industrial cathode assemblyCathode assembly. Coupled with advanced software for accurate geometrical data processingProcessing, this well-established approach offers promise for interface analysis in various applications. The results obtained reveal a highly asymmetric air-gap distribution on both the top and side contact surfacesSurface of the cast ironIron-carbon cathodeCathode interface.