THEORETICAL AND TECHNOLOGICAL PROBLEMS ON SMELTING OF LOW PHOSPHORUS STEEL

Low phosphorus steel is an important part of clean steels. The correlative theoretical and technological problems on low phosphorus steel were studied from the rephosphorization control and dephosphorization of molten steel in ladle and the dephosphorization with ferromanganese The results show that there is a critical basicity and a critical oxidizability for CaO-based top slag of ladle to control the dephosphorization and rephosphorization of molten steel, and for ferromanganese dephosphorization there is a critical content [%C] * corresponding to the maximal phosphorus distribution rate L p and the minimal manganese distribution rate L Mn . The dephosphorization rate of linkage treatment for dephosphorization and desiliconization in 100 kg induction furnace is 45 %～50 %