Rb2O-containing refining slag for ladle furnace

The invention discloses Rb2O-containing refining slag for a ladle furnace. The Rb2O-containing refining slag is used for steel for super-fine cutting wires, and comprises, by mass, 32-42% of CaO, 40-52% of SiO2, not larger than 8% of Al2O3, not larger than 10% of Rb, and smaller than 5% of MgO. According to the Rb2O-containing refining slag for the ladle furnace, the Rb2O-containing refining slagwith the new chemical component proportion is prepared by adding the Rb2O, and the capacity, used for adsorbing and removing inclusion in molten steel, of the Rb2O-containing refining slag is substantially improved. In an industrial experiment, after the steel for the super-fine cutting wires is refined by using the slag, the inclusion amount is remarkably decreased, the size is controlled to be smaller than 5 [mu]m, and accordingly, the super-high-purity steel for the cutting wires is obtained. Meanwhile, the breaking rate of the finished cutting wires and steel cords in the detecting and using processes is greatly d