Abstract：In order to develop better refractories to improve the purity of saw wire steel, the effects of MgO and MgO-CaO refractories on inclusions in the 95Cr saw wire steel were studied using MoSi2 furnace in the present experiment. The results indicated that both MgO and MgO-CaO crucibles can control the composition of all of the elements in the steel within the target range and the drop point of inclusion composition within the target low melting point zone. However, compared with the MgO crucible, the MgO-CaO crucible has a better effect in purifying the molten steel, mainly in two aspects. On the one hand, the contents of P, S, [Al]s and T[O] in steel are lower. Especially, the w([S]) can be reduced to 0.000 6%, the w([Al]s) to 0.000 3% and the w(T[O]) to 0.000 5%. On the other hand, the number of inclusions in steel is less, the size is smaller, and the content of Al2O3 in composite inclusions is lower. Specifically, the proportion of inclusions with an effective diameter of less than 2 μm in steel is 91% after smelting with MgO-CaO crucible, while that of the steel smelted with MgO crucible is only 78%. Moreover, after the MgO-CaO crucible smelting, the mass percent of Al2O3 in complex inclusions in steel is almost less than 10.0%. This is mainly because both MgO and CaO in MgO-CaO refractories can remove P, and CaO also removes S and Al2O3 inclusions in the steel.
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