Method for improving cleanliness of molten steel in IF steel RH vacuum smelting process

The invention relates to the technical field of metallurgical steelmaking, and particularly discloses a method for improving the cleanliness of molten steel in the RH vacuum smelting process of IF steel, which comprises the following steps: 1) after natural decarburization of the molten steel under RH vacuum is completed, the current vacuum degree is still kept; 2) adding carbon powder into the molten steel through an RH vacuum hopper, and implementing a carbon deoxidation process; (3) the adding amount of the carbon powder is controlled according to the content of residual oxygen in the molten steel, and the adding amount of the carbon powder follows the following calculation formula: W carbon powder = ([O] residual-100) * W molten steel/240 * K; 4) after the carbon powder is added, carrying out vacuum circulation on the molten steel, and carrying out oxygen determination and deep deoxidation; according to the method, the deoxidation process is implemented through accurate carbon powder input, on the basis o