A narrative review: The electromagnetic field arrangement and the “braking” effect of electromagnetic brake (EMBr) technique in slab continuous casting

Electromagnetic brake (EMBr) technique is adopted to reduce the turbulence of molten alloy in the slab mould in the continuous casting process, especially under high casting speed. We introduce a state-of-the-art EMBr technique by reviewing the published literature. The main objective of this paper is to give a clear view of the EMBr technique in terms of the magnet arrangement, along with their “Braking” effect to help decision-making. The EMBr system can be divided into three types, in terms of the magnet arrangement: the Local type, the Ruler type and the Multi-mode type, respectively. Both advantages and disadvantages of each type have been discussed. Further challenges are also raised.

Analysis of Chemical Composition Homogeneity in the Cross-section of the Rods Produced from Alloys of 6xxx Group

The alloys from Al–Mg–Si system provide an excellent combination of mechanical properties, heat treatment at extrusion temperature, good weldability, good corrosion resistance and formability. Owing to the high casting speed of rods or slabs, the solidification is rather non-equilibrium, resulting in defects in the material, such as crystalline segregations, the formation of low-melting eutectics, the unfavourable shape of intermetallic phases and the non-homogeneously distributed alloying elements in the cross-section of the rods or slabs and in the entire microstructure. The inhomogeneity of the chemical composition and the solid solution negatively affects the strength, the formability in the warm and the corrosion resistance, and can lead to the formation of undesired phases due to segregation in the material. In this experimental investigation, the cross-sections of the rods from two different alloys of the 6xxx group were investigated. From the cross-sections of the rods, samples for differential scanning calorimetry (DSC) at three different positions (edge, D/4 and middle) were taken to determine the influence of inhomogeneity on the course of DSC curve. Metallographic sample preparation was used for microstructure analysis, whereas the actual chemical composition was analysed using a scanning electron microscope (SEM) and an energy dispersion spectrometer (EDS).

The Overview on Sticking Breakout Behavior for Thin Slab Continuous Casting

Breakout is the most detrimental event associated with the continuous casting process, with the overview of the sticking breakout behavior, a lot of valuable things had been acquired. For the mechanism of the sticking breakout forming, the key for the breakout prevention is decreasing the probability of the hot spot; the content of the carbon or alloy element, the wear and tear of the mould corner, the mould flux, the fluctuation of the casting speed and the fluctuation of the meniscus are easy to cause the sticking; and with high casting speed and the funnel mould, the thin slab continuous casting is more easier to lead to sticking breakout than the normal strand.

Researches on the Behavior of Carbon and Sulfur Segregations of 82B Billet

The behavior of carbon and sulfur segregations of 82B hard wire steel produced under different continuous casting conditions has been systematically studied by the combination of field trial and laboratory analysis. The results showed three factors such as superheat degree, casting speed and F-EMS which influenced the segregation of billet worked differently with the variations of inner positions of the billet and segregation elements. For the central segregations of carbon and sulfur, the dominant factor was casting speed. Under high casting speed, proper increase of secondary cooling intensity could effectively decrease carbon and sulfur segregations of billet, especially for the central position of billet. The hydraulic simulation of the tundish showed the optimal casting speed should be 1.8m/min.

Research on Thermocouple Embedded Theory for Thermal State of CC Mould Copper Plate with High Casting Speed

High casting speed would change the thermal state of the mould copper plate, The coupled visco-elasto-plastic FEM models have been presented for thermal process analysis of steel shell and the mould copper plates. With the understanding to the mould thermal state for different casting speed, the characters of mould copper plate thermal flux is obtained. It is shown that, the highest thermal flux zone is getting downward with casting speed increasing, and it would also make harder for breakout signals catching.

Research on Hot State of Mould Copper Plate with High Casting Speed

High casting speed has a great influence to thermal state and strain/stress field of the mould copper plate. The coupled visco-elasto-plastic FEM models have been presented for thermal process analysis of steel shell and the mould copper plates. It is shown that, when the casting speed is increasing, the turning point of the temperature distribution curve is getting further to the meniscus; and the increasing casting speed has no influence to the equivalent strain distribution along the thickness direction of the mould.

Research on Thermocouple Embedded Position for CC Mould Copper Plate with High Casting Speed

High casting speed would increase the occurrence probability of sticking, and make it harder for breakout signals catching. The coupled visco-elasto-plastic FEM models have been presented for thermal process analysis of steel shell and the mould copper plates. With the understanding to the mould thermal state and deformation for different casting speed, the principle for the layout of thermocouples is obtained. It is shown that, the set of the thermocouples to the meniscus for the plates should be decided by the highest design casting speed, and the location of the thermocouples from the cold side of the plates is deeper, the breakout signals would be caught easier.