Next-generation steelmaking: process integration and technological advances in primary reduction, ladle metallurgy, and solidification

This review addresses process integration across primary reduction, melting, secondary refining and solidification, capturing the essentials of secondary refining, particularly the control and adjustment of slag basicity, as well as the improvement of metal bath properties through ladle metallurgy techniques, including refinement, dispersion, homogenization, and stirring. It also considers the integration of advanced solidification technologies to enhance efficiency. The objective of this work is to synthesize recent developments across these stages and identify how process variables interact at their interfaces, providing an overview of metallurgical advances and their implications. The methodological approach is based on a structured and critical literature review, organized to trace how thermodynamic, mass-transfer, and fluid-flow variables carry over between stages and ultimately determine solidification structure and defect formation. Each section of the manuscript reflects an area with significant gaps, chosen based on actual industrial needs, and closes by relating those gaps to the adjacent process stage, aiming to guide the interpretation and application of scientific information to address industrial challenges. Key findings indicate that crack formation during solidification is closely associated with high solid fractions and critical thermal conditions, requiring precise control of cooling and casting design to minimize defects and residual stresses. Furthermore, the optimization of slag properties and heat transfer conditions is a key factor in process stability and final steel quality. Overall, these elements provide a structured foundation for industrial decision-making and guiding future applied research. Together, the sections of the manuscript provide an interpretative framework that helps readers apply scientific knowledge systematically to address industrial challenges.