Steelmaking Technology Area

Area Head

Objectives

• To conduct technological research to understand better the fundamentals of the steelmaking process.
• To collaborate with process engineers in the solution of quality and production problems.
• The coordination of the steelmaking related activities that are carried out in CINI departments.

Research areas

Primary operations

• Evolution of slag and metal composition along the process.
• Model of slag-metal reactions.
• Optimization of blowing pattern and fluxes.
• Foaming of slags.

Change of slag composition during converter operation

Evolution of phosphorus content during the process. Comparison between measured and calculated values

Evolution of carbon content during metal refining in the converter. The contribution of metal droplets to the decarburation reaction is analyzed

Particle size distribution of droplets in the metal-slag emulsion

Ladle metallurgy

• Clean steel practices

• Tests adding tracer to the ladle slags to investigate sources of macroinclusions.
• Influence of process parameters on the quantity, size distribution and composition of inclusions along the process.
• Model to predict inclusion composition after calcium treatment.
• Analysis of castability problems.

Influence of Calcium treatment on the type of inclusions formed and its relationship with nozzle clogging

Evolution of steel and inclusion composition after Calcium treatment. Calculated and measured values are compared

EDAX mapping showing the presence of BaO in one of the inclusions

• Ladle slags

• Prediction of the slag composition.
• Estimation of slag properties.
• Calculation of saturation conditions.
• Definition of the most favorable combination of fluxes added at tapping.
• Analysis of desulphurization reaction.

Influence of the oxygen activity at the EAF before tapping on the ladle slag composition. Comparison between measured and calculated values

Influence of slag composition on the amount of MgO necessary to saturate it with Periclase

Continuous casting

• Influence of process parameters on the solidification structure.
• Effect of Electromagnetic Stirring on the macro and microstructure.
• Behavior of casting fluxes. Analysis of plant trials
• Evaluation of mold signals to monitor the process. Relationship with defects.
• Hot ductility tests to identify low ductility regions.

Effect of EMS intensity on the size of the Central Equiaxed Zone

Analysis of crack formation in a continuous casting product. Note the presence of dendrites in the fracture surface

Microsegregation analysis in continuously cast products. Note interdendritic segregation.

Relationship between defect formation and temperature variability registered by mold thermocouples