The purity of clean steel directly governs its mechanical properties. As a highly efficient deoxidizer and sulfide modifier, magnesium plays a critical role in clean steel production. This paper reviews magnesium treatment technology, analyzes the thermodynamics and kinetics of reactions between magnesium and inclusions, elucidates the regulatory effects of magnesium on inclusion evolution, size and distribution, and presents the merits of magnesium-rare earth composite treatment. Finally, the development trends are prospected and novel processes proposed, providing guidance for fabricating high-quality clean steel.
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