Macrosegregation Quality Criteria and Mechanical Soft Reduction for Central Quality Problems in Continuous Casting of Steel

Mostafa Omar El-Bealy

Companies Chair of Metals Processing & Technology, MTC/Egypt, CTU/Germany, KTH/Sweden, MIT/USA, Sweden Branch: Division of Casting of Metals, Department of Materials Science and Engineering, Royal Institute of Technology, Stockholm, Sweden.

DOI: 10.4236/msa.2014.510074                

Abstract

In order to study the central quality of continuously cast tool steel slabs, the simple model has been developed to simulate the macrosegregation quality criteria. The model calculates different quality criteria such as average macro-segregation level criterion “ASL”, its fluctuation level “FSL” and its segregation quality number “SQN”. These criteria are calculated based on the previous measurements of carbon and sulfur concentrations distributions in final region of spray zones and centerline area of lower and upper slab sides. The effect of mechanical soft reduction Technique “MSR” on the slab centerline quality is examined and analyzed. The model results show that MSR affects the quality of centerline areas significantly by different ways based on the casting speed. The experimental and theoretical results clarify that the qualities of different slab sides are different for all collected samples. The model results show also that the accuracy of the macro-segregation quality criteria increases quantitatively with increasing the number of analyzed segregated elements. Therefore, the macrosegregation quality criteria and their distributions can be considered as the most simple and vital tool to evaluate the various slab qualities. Finally, the mechanism of centerline segregation formation with mechanical soft reduction is discussed in this study.

Keywords

Continuous Casting of Steel, Macrosegregation, Centerline Segregation, Macrosegregation Quality Criteria, Mechanical Soft Reduction Technique

Conflicts of Interest

The authors declare no conflicts of interest.

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