A method of treatment of a running ferrous alloy sheet containing at least one easily oxidized element is provided. The method includes a step of immersion of the sheet in a molten oxides bath.
The molten oxides bath has a viscosity between 0.3.10−3 Pa·s and 3.10−1 Pa·s, the surface of the bath is contact with a non-oxidizing atmosphere, and the molten oxides are inert towards iron. The residence time of the running sheet in the bath is at least 1 s and the residues of oxides remaining on the surfaces of the sheet at the exit of the bath are eliminated.
A treatment line of a ferrous alloy sheet for implementing the method, is provided. The treatment line includes a molten oxides bath having a viscosity between 0.3.10−3 and 3.10−1 Pa·s. The surface of the bath is contact with a non-oxidizing atmosphere, and the molten oxides are inert towards iron.
Mechanical devices for eliminating the residues of molten oxides remaining on the surfaces of the ferrous alloy sheet are at the exit of the molten oxides bath.