Abstract
Cathode materials mainly deteriorate through physical erosion and chemical / electrochemical corrosion. The wear patterns are characterised by a “W-shape” and localised potholes. A variety of materials such as alpha alumina and refractory hard materials have been used for protecting conventional cathodes. TiB2 based refractory hard materials are well suited for this. They satisfy the electrical conductivity requirements, have a very low solubility in molten aluminium and are wetted by aluminium providing potential benefit in modifying design and operation. This study was to explore the potential of increasing life for graphitised cathodes using TiB2 grains without compromising metal purity, cell performance or lining design. Statistical analysis of measurements confirms that cathode life could be increased by at least 2 years. The study revealed that cathode life could be increased by at least 2 years. Increases in B and Ti impurities seen in pot metal were within casthouse tolerance limits.
Keywords
Cathode TiB2 protection granulePreview
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