(1) When the molten metal reaches 1260 o C, either calcium boride or lithium should be plunged into the molten bath to deoxidize the melt.(2) Carbon steel can be classified, according to various deoxidation practices, as rimmed, capped, semi-killed, or killed steel.(3) In some foundries in which combustion cannot be properly controlled, oxidizing fluxes are added during melting, followed by final deoxidation by phosphor copper.(4) These steels are not deliberately strengthened by alloying elements other than carbon; they contain some manganese for sulfur stabilization and silicon for deoxidation .(5) Most commercial steels contain about 0.5% manganese to serve as a deoxidizer and to tie up sulfur as manganese sulfide, thereby preventing the occurrence of hot-cracking.(6) In steels of this type, silicon is added as the deoxidizer followed by the addition of aluminum for grain size control.(7) In a vacuum furnace, carbon is an excellent deoxidizer , and the deoxidation product, carbon monoxide gas, is continuously removed under vacuum.(8) In tin bronze, phosphorus has traditionally been the deoxidizer , hence the name ‘phosphor bronzes’ for these alloys.(9) When the cast electrodes of air-melted steel are remelted under vacuum and deoxidized with carbon, the product has significantly improved purity.(10) A second limey slag is used to remove sulphur and to deoxidise the metal in the furnace.(11) Aluminum, on the other hand, not only deoxidizes the steel, but also refines the grain size.(12) Aluminum is widely used as a deoxidizer and was the first element used to control austenite grain growth during reheating.(13) In a vacuum furnace, carbon is an excellent deoxidizer, and the deoxidation product, carbon monoxide gas, is continuously removed under vacuum.(14) For deoxidation of carbon and low-alloy steels, aluminum, titanium, and zirconium are used.
