한국주조공학회

For the purpose of development of domestic carburizer, when the basicity of ash in carburizer was changed from Na_2O/Al_2O_3+SiO_2 0.06 to Na_2O/Al_2O_3+SiO_2 0,196wt%, using Na_2O as flux for domestic graphite resource (Bong Myung armorphous graphite), carburizing efficiency was improved as basicity increased, optimum basicity value was Na_2O/Al_2O_3+SiO_2: 0.151. This means that Na_2O contributed to lower viscosity of slag and raise occurence probability of specific reaction surface between molten iron and carburizer. The experiment of effect of general characteristics offecting carburizing ability of this carburizer was performed, the result is that 10/30 mesh was optimum size of the carburizer and as carbon equivalent of molten iron was higher, carburizing ratio was lowered, but when si concentration was below 1.8% in general cast iron melting region, recovery showed 75-85%. As agitation rate of molten iron and temperature interval were higher, Carburizing ratio was increased and showed max, 94%. Desulfurizing phenomena of molten iron by Na_2O in carburizer didn't appear.