摘要:Thermodynamic conditions to modify Al2O3inclusions in bearing steel GCr15 by Mg have been calculated which was obtained that as [Als] was 0. 03%, 2. 0 x 10-6% Mg in steel could modify the Al2O3to form MgO·Al2O3. With added 1 g magnesium aluminum powder containing 16. 55% Mg in 1 kg bearing steel liquid in a MoSi2 electric resistance furnace to test the effect of Mg on Al2O3inclusion modification. The test results showed that after added Mg, ≥10μm Al2O3inclusions were modified to fine, spherical magnesium-aluminum spinel inclusions, of which ≤5 μm inclusions accounted for 99. 46% , others were 5 ~ 10 μm inclusions.