Mold Thermo-Mechanical Rigidity Criterion for Surface Quality of Continuous Casting of Steel

Mostafa Omar El-Bealy

Materials Processing and Technology Chair in Royal Institute of Technology, Stockholm, Sweden.

DOI: 10.4236/msa.2013.41006                

Abstract

A theoretical investigation of heat flow, solidification and solid shell resistance “I_c” has been undertaken by using a mathematical model and previous plant trials. The ultimate purpose is to develop operating conditions and therefore to improve the surface quality for continuously cast steel slabs. A new simple criterion called mold thermomechanical rigidity “MTMR” has been proposed to evaluate and to improve these purposes. The parameters of MTMR and its non-dimensional number which use to control the surface defects are present in this investigation. Previous plant trails of slab surface defects formation have been investigated thermo-mechanically with this criterion. The predications show that this criterion is very sensitive of operating parameters and is a significant qualitative tool to evaluate the surface quality. From examination of the behavior of MTMR, the susceptibility and mechanism of surface defects formations with MTMR have been primarily discussed.

Keywords

Continuous Casting of Steel; Surface Quality; Solid Shell Resistance

Conflicts of Interest

The authors declare no conflicts of interest.

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