Modeling of Inclusion Capture in a Steel Slab Caster with Vertical Section and Bending

Metals

BrianG. Thomas¹  Seong-Mook Cho¹  Jong-Geun Bang²  Jong-Yeon Hwang²  Il-Sin Bae² 

[1] Department of Mechanical Engineering, Colorado School of Mines, Brown Hall W470-I, 1610 Illinois Street, Golden, CO 80401, USA;Iron & Steel Process Engineering Research Group, POSCO Technical Research Lab., POSCO, Pokposarang-gil, Jeollanam-do, Gwangyang-si 57807, Korea;

关键词: steels;    continuous casting;    inclusions;    entrapment;    engulfment;    defects;   

DOI  :  10.3390/met11040654

来源: DOAJ

【 摘 要 】

Particles in molten steel, including argon-gas bubbles, slag droplets, and non-metallic inclusions, are removed into the surface-slag layer or captured by the solidifying steel-shell during continuous steel casting. Captured particles often become serious defects in the final steel product, so understanding particle-capture mechanisms is important for steel quality. Slab casters often have a straight mold and upper-strand prior to a curved lower-strand. The present work investigates particle capture in such a caster using computational modeling with a standard k-ε model for molten-steel flow, a discrete phase model for inclusion transport, and an advanced capture criterion for inclusion entrapment and engulfment into the steel shell. A new postprocessing methodology is presented and applied to predict inclusion-capture rates in commercial cast product. The locations and size distributions of particles captured into the shell, and actual capture rates are quantified. The model predictions are validated with ultrasonic-test plant measurements of the locations of large particles captured in a steel slab. The results reveal how large-inclusion capture accumulates in the beginning of the curved strand, leading to a capture band in the slab inside radius. Finally, the capture fractions and locations due to all capture mechanisms are compared for different inclusion sizes, and the implications are discussed.

【 授权许可】

Unknown