Separation of Non-metallic Inclusions from Molten Steel Using High Frequency Electromagnetic Fields

Chen

Jiang

et al. 2019

steel research int.

Self Cite

Considering the gap between the copper mold and the solidified shell (mold-bloom gap), the electromagnetic field, fluid flow, solidification, removal of inclusions, and slag entrainment in the bloom continuous casting process with mold electromagnetic stirring (M-EMS) are numerically investigated. As the mold-bloom gap is considered, the electromagnetic force increases with the distance from the meniscus and reaches a maximum value near the stirrer center. With the distance further increasing, the electromagnetic force decreases continuously. With the mold-bloom gap ignored, there are two peaks of the electromagnetic force along the distance below the meniscus. One is 40 mm above the stirrer center and the other is near the mold exit. When the mold-bloom gap is considered, the velocity magnitude is higher and the temperature field on meniscus is more uniform. The net slag entrainment rate is 0.0144 kg s À1 and is higher than that ignoring the mold-bloom gap. Inclusions are more removed with considering the moldbloom gap.

Section: Mathematical Formulationmentioning

confidence: 99%

Effect of the Gap Between Copper Mold and Solidified Shell on the Fluid Flow in the Continuous Casting Strand with Mold Electromagnetic Stirring

Chen

Jiang

et al. 2019

steel research int.

Self Cite

“…Li et al [12] designed an electromagnetic stirring method and improved inner porosity and composition segregation of steel bloom. Wang et al [13] found that fluid flow induced by electromagnetic force had a close relationship with inclusions of steel based on both the experiment and the simulation results and verified that electromagnetic technology was a feasible and high-efficient method to control inclusions of the molten steel.…”

Section: Introductionmentioning

confidence: 82%

“…Enhancing the cooling rate and introducing physical fields are the two common methods for controlling the MnS precipitation of steel. [9][10][11][12][13] It has been reported that MnS precipitates in the as-cast steel should have a mean length lower than 5lm for to obtain better machinability and mechanical properties. [9] Wang et al [10] found that the percentage of the large MnS with a length over 5lm decreased from 6.2 to 2.6 pct as the solidification condition changed from air cooling to sub-rapid.…”

Section: Introductionmentioning

confidence: 99%

Effect of Permanent Magnet Stirring on MnS Precipitation, Microstructure Evolution, and Mechanical Properties of High-Sulfur Micro-alloyed 49MnVS3 Steel

Peng

Huang

et al. 2022

Metall Mater Trans B

An experimental investigation has been conducted with respect to the influence of permanent magnet stirring (PMS) under different rotation speeds (0, 50, 150 rpm) with a center magnetic flux density of 1450Gs on the evolution of MnS precipitation, microstructure, and mechanical properties of high-sulfur micro-alloyed 49MnVS3 steel. The thermodynamic calculation results indicated that the MnS began to precipitate in 1419 °C and accounted for more than 84 pct of the total in the final solidification temperature of 1404 °C. The experimental results revealed that when the rotation speed increased from 0 to 150 rpm, the mean length of MnS decreased from 7.2 to 3.2 lm, and the distribution of MnS precipitates was more random and uniform, due to the PMS-enhanced turbulent flow with a magnetic Taylor number of 9.21 9 10 7 . Moreover, the content of the intragranular ferrite (IGF) increased rapidly from 0.3 to 3.1 pct, while the content of grain boundary ferrite (GBF) decreased from 11.2 to 9.2 pct after PMS with the rotation speed increased from 0 to 150 rpm. The increased formation of ferrite is related to the precipitation of (Ti, V, Nb) (C, N) on the edge of more small uniformly distributed MnS. In addition, the tensile strength and toughness of the 49MnVS3 steel are enhanced owing to the beneficial changes of increased small-sized MnS precipitates and promoted the formation of intragranular ferrite.

“…The electromagnetic thermal effect can effectively compensate for the temperature of molten steel, reduce the temperature fluctuation of molten steel in the tundish, and achieve the goal of constant temperature pouring with low superheat in the tundish [ 18 , 19 ]. The electromagnetic force effect is reflected in the “pinch effect” generated by the electromagnetic field, which makes non-metallic inclusion particles with small density and poor conductivity move toward the channel wall, where they are finally removed [ 20 , 21 ]. Compared with tundish, and without an induction heating device, the IHT cannot only ensure the outlet temperature but also make use of the temperature difference to generate the density difference to make the molten steel have an upward trend in the distribution room, which is conducive to reducing short circuits and increasing the average residence time.…”

Section: Introductionmentioning

confidence: 99%

Channel-Type Induction Heating Tundish Technology for Continuous Casting: A Review

et al. 2023

Materials

With the increasing demand for special steel, the quality of steel has become critical during the continuous casting tundish process. In recent years, tundish heating technology has played a key role in low superheat casting. Toward this, researchers have reported on the metallurgical effects of induction heating tundish (IHT). From 1984 to date, the channel-type IHT has been investigated in the production of continuous casting of special steel. In this article, the principle of this channel-type IHT technology and equipment composition were illustrated. A brief summary and comments were undertaken on the channel-type IHT, including physical modeling and numerical modeling. The application development trend of tundish induction heating equipment is summarized combined with industrial application data, which provide a reference for a better understanding of the induction heating process of tundish.