Effect of Ti Content on the Characteristics of Inclusions in Al-Ti-Ca Complex Deoxidized Steel

Experiments with different titanium addition were carried out in alumina crucible without slag at 1 873 K to investigate the variation of inclusion composition, size and morphology in Al-Ti-Ca complex deoxidized steel. The samples exacted from the experimental steels were analyzed by field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). Titanium influence significantly on the morphology, size distribution and composition of oxide inclusions in Al-Ca deoxidized steels, and the inclusions characteristics vary with titanium content. Liquid oxide inclusions are promptly modified by titanium. On the other hand, titanium can also change solid calcium aluminate inclusions into spherical ones in the melts similarly, but there are a number of inhomogeneous inclusions in molten steel at the initial stage. Therefore, to modify inclusions better, the content of titanium and calcium in molten steel should be controlled simultaneously during the production process.