Effect of Calcium Treatment on the Inclusions of 20CrMnTi Steel During the Refining Process

摘要

To alleviate the nozzle clogging during continuous casting of 20CrMnTi steel, the optimization of calcium treatment during refining process was conducted in the current study. "I'he thermodynaraical relation between the compositions of molten steel and the precipitation of inclusions after the calcium treatment was discussed in detail, arid then an industrial experiment was earned out. The obtained target compositions of refining slag with optimized calcium treatment were made up of CaO=50~ 55wt%, Al_20_3 =30~35wt%, SiO_2≤10wt% and MgO≈5wt%, with T.Ca=20~60 ppm, [S]≈150 ppm. T.O≤20 ppm, [Mg]≈2 ppm in molten steel.