Effect of Sulfur Mass Fraction on Inclusions in Steel E36 Deoxidized by Titanium and Zirconium

In order to study the effect of sulfur mass fraction on inclusions in steel E36 deoxidized by titanium and zirconium,steelmaking experiments of three heats of steel E36 were done in a Mo Si2 furnace with 70 mm × 100 mm Mg O crucible at 1 873 K. The results showed that most of the inclusions in steel E36 deoxidized by titanium and zirconium are spherical inclusions of Ti Ox and Zr O2 coated by Mn S. The typical inclusions are Al2O3-Ti Ox-Mn S,Mg O-Si O2-Al2O3,Al2O3-Si O2-Ti Ox-Zr O2 and Ti Ox-Si O2-Al2O3-Mn S. With the increasing of the sulfur mass fraction in steel,the inclusion percentages with the diameter less than 10 μm increase to 99. 5%; the average diameter of the inclusions reaches 2. 3 μm from 1. 7 μm; the sulfur mass fraction in the inclusions and the area of Mn S in single inclusion are also bigger,the area is 0. 15% when w[S] is0. 001 5%,and it becomes 0. 72% when w[S] is 0. 011%.