Anti-Wear Enhancement of Silicon-Grey Cast Iron for the Production of Grinding Plates: Effect of Snail Shell Powder as Carbide Forming Material

Abstract

Grinding plates produced with silicon-grey cast iron wear out quickly. As a result of this molten grey iron is treated with ferrochrome to produce hard and wear resistant grinding plates. This makes the cost of the grinding plates very expensive for the rural community to purchase them for their domestic grinding operation. Because of this limitation this present research study looks at the effect of snail shell powder on the properties of grey cast iron with a view to using it as an alternative to conventional ferrochrome for the production of grinding plates. The grey cast iron scraps were melted in a crucible furnace. Ladle treatment of the molten metal was done by varying the percentage of snail shell powder from 0.1 to 0.5. The same process was repeated for ferrochrome to serve as a control. The molten metal was poured into a prepared sand mold. The microstructure, spectrometer analysis, hardness, wear and tensile properties were studied. The results show that the tensile strength increased with increasing snail shell powder up to a maximum value of 0.4 % and the hardness values increased linearly as the snail shell powder increased, while the wear rate decreased continuously with increasing composition of snail shell powder. The microstructure of all a samples showed the network of interdendritic cementite (white) surrounded by patches of pearlites. The practical test of the grinding plates was conducted and found that the developed grinding plates gave 96.7 % efficiency. The results obtained for the snail shell powder samples compare favorably with conventional ferrochrome. This work has established that snail shell powder can be used as an alternative to ferrochrome for the production of white cast iron for grinding plate’s application.