Method for reducing activity of aluminum oxide in U75V refining slag by adopting rare earth oxide

The invention discloses a method for reducing the activity of aluminum oxide in U75V refining slag through rare earth oxides, a U75V steel smelting production process comprises the steps of converter-LF external refining-VD/RH vacuum refining-bloom continuous casting, rare earth alloy is directly added into U75V molten steel, the rare earth alloy participates in deoxidation, the oxygen content in the molten steel and the refining slag is effectively reduced, and the activity of aluminum oxide in the U75V refining slag is reduced; and a rare earth compound generated by deoxidation is combined with Al2O3 in the slag to form a stable aluminate rare earth compound, so that the activity of aluminum oxide in the slag is reduced, the transfer of aluminum and oxygen on a slag-steel interface is reduced, the stability of the refining slag is improved, and the removal of aluminate inclusions in the steel is promoted. 本发明公开了一种采用稀土氧化物降低U75V精炼渣中氧化铝活度的方法，所述U75V钢冶炼生产工艺为：转炉-LF炉外精炼-VD/RH真空精炼-大方坯连铸，本发明向U75V钢液中直接加入稀土合金，稀土合金参与脱氧