The composition, amount and size of non-metallic inclusions, as well as the variation of T.O and N along the thickness of a Q345D/E steel slab, were investigated in the current study. The distributions of T.O, N and inclusions were very inhomogeneous. The contents of T.O on the loose side was obviously higher than those on the fixed side, and the contents of N increased from the surface to the center of slab thickness. From the surface to the 1/4 thickness of slab, the inclusions changed from calcium aluminate to the complex ones composed of MgO- Al_2O_3 and CaS, then gradually changed back to the calcium aluminate from the 1/4 thickness to the region around thickness center. The content of CaO and the amount of inclusions presented a "W" shaped trend along the thickness of slab. From the the surface to the thickness center of slab, the content and size of TiN in inclusions increased significantly, which agreed well with the evolution of N along the thickness direction. The reasons for the inhomogeneity will be further studied in the future.
展开▼
