Factors Affecting the Production of Fines During the Screening and Handling of High-Carbon Ferromanganese

摘要

This investigation was undertaken in an attempt to determine the factors responsible for the high proportion of fines obtained in normal plant operation, and to develop procedures to minimize the production of fines. Part I describes the testwork that showed rapid cooling of the alloy and marked temperature gradients within the cooling slab of cast alloy to be the prime causes of the problem. Cooling of the top of the slab by water sprays seriously aggravated the problem. In addition, it was clearly demonstrated that, when 'layer casting' was practiced, the rapid reheating of the lower layer (which occurred when the molten alloy was poured onto it) resulted in serious shattering, giving a high proportion of fines. Part II includes an account of work done on a type of mold that had been proposed for use in a continuous casting machine.