Analysis of 13Cr bloom solidification structure using CA-FE model

Abstract

Solidification structure is critical in the control of the mechanical properties and quality during the continuous casting process. The thermo-physical properties of 13Cr steel added some rare metals, such as Mo, V, Nb, are measured to better understand the solidification structure of 13Cr bloom. A computational model using CA-FE (cellular automation-finite element) method coupled with heat transfer model is developed to describe the solidification structure in continuous casting process. It is found that the calculated solidification structure is in good agreement with the observed data. The influence of casting speed and superheat on the solidification structure of the bloom is studied in detail. In order to obtain more equiaxed crystal ratio and low degree of the segregation in the bloom, the optimized casting speed 0.6 m/min and superheat less than 25 °C are determined for the caster. Using the optimized manufacturing parameters, these samples are 60% with the equiaxed zone ratio of 8%–10% and below the degree of segregation 1.05.

Keywords

cellular automation / solidification structure / equiaxed crystal ratio / bloom / continuous casting

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