Effect of Ca and Ti contents on characteristics of inclusions in Fe–Si–Cr–Mn–Al–Ti–Ca–O melts

Effect of Al–Ti Concentration on Alumina Inclusions Aggregation Floating Behavior in Molten IF Steel

“…Meanwhile, thermodynamic calculations also indicate that adding trace amounts of titanium to aluminum-killed steel makes it difficult to form Al-Ti-O inclusions, even Ti-O inclusions. [46][47][48] The section of the steel sample rod taken out through a quartz tube and quickly water-cooled was ground and polished after adding different aluminum or titanium concentrations, and the number and size of inclusions in the entire circle with areas of 16π mm 2 were counted by SEM and OM. The size and number of inclusions in the interior of steel for different aluminum and titanium concentrations with section areas of 16π mm 2 are shown in In contrast, the size and number of inclusions in the interior of high-titanium steels are larger than others.…”

Evolution mechanism of inclusions during refining and continuous casting process of 321H stainless steel

“…For Al-killed molten steel, calcium treatment is carried out as a routine technology in steelworks in order to solve the clogging of SEN during CC process, which can effectively modify the solid alumina and spinel (MgO•Al 2 O 3 ) inclusions to liquid calcium aluminate inclusions [40][41][42]. Many researchers [40][41][42][43][44][45][46][47][48] have investigated the evolution mechanism, reaction steps and reaction kinetics, morphology and size characteristics of aluminate-based inclusions in Al-killed molten steel during calcium treatment process on both thermodynamics and experiment scale. It was found that the evolution followed route of 'Al 2 O 3 →MgO•Al 2 O 3 →CaO-Al 2 O 3 -MgO' during the refining process [39,41,42].…”

“…Generally, the modified inclusions have a two-layer structure with a core of MgO·Al 2 O 3 and outer layer of CaO–Al 2 O 3 –MgO [39]. Currently, few investigations on inclusion modification by calcium treatment in Ti-bearing steel are reported [36, 43–45, 47, 48]. Li et al [43] investigated the evolution mechanism of non-metallic inclusions with Ca treatment of Al-killed, Ti-bearing steel by industrial trials and thermodynamic calculation, and found that at high calcium content the formation of calcium titanates might lead to the decrease of titanium yield and the clogging of the submerged entry due to the formation of solid calcium titanates.…”

“…Currently, few investigations on inclusion modification by calcium treatment in Ti-bearing steel are reported [36, 43–45, 47, 48]. Li et al [43] investigated the evolution mechanism of non-metallic inclusions with Ca treatment of Al-killed, Ti-bearing steel by industrial trials and thermodynamic calculation, and found that at high calcium content the formation of calcium titanates might lead to the decrease of titanium yield and the clogging of the submerged entry due to the formation of solid calcium titanates. Zhang et al [48] reported the Al–Ca–Ti–O phase diagram and summarised that higher calcium treatment level is more easily to modify the inclusions into the liquid phase ones in low titanium content steel.…”