Abstract: The technology of AODIF (Argon-Oxygen Decarburization Induction Furnace) for small scale smelting of special steels is introduced. The technology gives such refining capabilities as deep decarburization to common non-vacuum induction furnaces with effective control of temperature and chemical reactions respectively. After the disscussion of the phiscal chemistry basis involing decarburizaton,oxygen supply and heating features of AODIF,it has been found that altra-low carbon steels can be produced with precise control of smelting point by the reasonable and flexiable AODIF process, which permits both gas and solid oxygen supply.