Feasibility of Sea and Coconut Shells as Substitute to Barium Carbonate (BaCo₃) in Small Scale Foundry and Heat Treatment Shop in Nigeria

Abstract

Barium Carbonate (BaCo₃) is commonly used as an energizer in pack-carburization. Investigation was therefore carried out to establish the suitability of sea shell and coconut shell as energizers in pack-carburization of mild steel. Samples were carburized at 950°C in carburization compounds containing charcoal and energizing aterials at predetermined proportions. The results obtained showed that sea shell was a more effective energizer than the coconut shell and compared favourably with barium carbonate. Sea shell showed 82.5% efficiency compared with BaCO₃ and 134.7% with limestone (CaCO₃) at 950° carburizing temperature. It was found that 30% sea shell addition to charcoal gave optimal carburization case depth which was 2.8 times the values obtained from 100% charcoal. However, there was no significant difference between 100% charcoal and compounds containing various proportions of coconut shell in the carburizing kinetics.