Reduction of longitudinal cracks index in peritectic grades slabs through the steel project and casting parameters optimizations
Francisco Necy Alves Júnior; Carlos Henrique Lopes; Carlos Alexandre Azevedo; Paula Renee Macedo Costa Bastos; Lucas Uchoa Sousa; Anderson Nicolodi; José Eduardo Pereira; Eugenio Pacelli Meireles de Araújo; Hilder Ferreira Caldas; Miguel Arcanjo Freitas Almeida
Abstract
The occurrence of longitudinal cracks in continuous casting steel slabs remains a recurring challenge in the steel industry, particularly for peritectic grades (0.08–0.15%C - ArcelorMittal Pecém reference), whose solidification behavior is inherently unstable. Due to the complexity of the phenomenon, its mitigation requires the combined assessment of metallurgical and operational factors. This study presents an integrated approach to reduce crack formation in slabs intended for heavy equipment (“Yellow Goods”) applications. The original steel grade was located within the peritectic zone and exhibited a Ferrite Potential (FP) between 0.85 and 1.05 - considered a critical range in the literature - which increases sensitivity to defect formation. Given this condition, three new steel grades were developed and repositioned outside the critical FP range while maintaining the required mechanical properties. Simultaneously, the continuous casting process was optimized through parameter standardization and the development of mould fluxes capable of equalizing the heat flux in the mould. As a result, longitudinal cracks were completely eliminated (reduced from 10% to 0%), demonstrating the effectiveness of the proposed metallurgical and operational solution.
Keywords
References
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Submitted date:
10/24/2025
Accepted date:
03/26/2026
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