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

Abstract

The evolution of inclusions during the refining and casting process was investigated on an industrial scale to clarify the quantity and distribution of non-metallic inclusions for 321H stainless steel. The analyses showed that Al 2 O 3 -SiO 2 -MnO-CaO and Al 2 O 3 as the main types of inclusions at the late of AOD and VOD, respectively. Pure titanium nitride and titanium nitride with oxide as the nuclei dominated the inclusions at the late of LF. The types of inclusions in mold and slab were similar to those obtained at the late of LF, while titanium nitride inclusions in slab were higher in numbers and larger in size. The titanium nitride inclusions precipitating with MgO-Al 2 O 3 -CaO-(TiO 2 ) nuclei showed a higher number density and area fraction than other oxide inclusions. The calcium treatment of molten steel was optimized by FactSage software and it was necessary to accurately control the calcium content in molten steel before titanium addition.

Study of Assimilation of Cored Wire into Liquid Steel Baths

“…The range of the error bars for the "experiment"-axis corresponds to the results shown in Table 3; for the "simulation"-axis, the range of the error bars corresponds to the change in thickness as the magnitudes of the contact thermal resistances are changed. Since the model matches the experimental conditions of the immersion of the cored wires, it is expected that simulations extrapolating to industrial processing conditions would allow for producing guidelines for optimization of the cored wire injection process, as a complement to established approaches that combine industrial trials with thermodynamic analyses [44][45][46][47][48][49][50][51][52][53][54][55]. lation"-axis, the range of the error bars corresponds to the change in thickness as the magnitudes of the contact thermal resistances are changed.…”