Development of a Novel Strand Reduction Technology for the Continuous Casting of Homogeneous High‐Carbon Steel Billet

Abstract

Internal quality issues concerning center segregation, porosity, and internal crack are the major problems with respect to the production of high‐carbon steels billet with a continuous casting process. Herein, a heat transfer calculation model is developed, verified, and applied to calculate the appropriate casting speed and secondary cooling intensity of the continuous casting billet with a section size of 160 mm square during mechanical reduction processes. The mechanical reduction on the homogeneity of the billet is investigated by several field trails to improve the internal quality of the high‐carbon 82 A steel billet. Consequently, a superoptimum crack‐free high‐carbon steel billet with high homogeneity both in segregation and in compactness is successfully achieved through a novel strand reduction pattern, combined with consecutive multiroll soft reduction and single‐roll heavy reduction.

On the Macrosegregation of Continuous Casting of High Carbon Steel Billet with Strand Reduction Process

“…Nevertheless, as the steel market asserts a more urgent claim for a high carbon billet with high homogeneity, and also with the continuous upgrading of modern equipped continuous casters for billet, the mechanical reduction process has recently been successfully applied in the continuous casting of steel billet [21,22]. This makes the numerical analysis of the mechanical reduction process for steel billet more important for practical implementation than ever, and it actually also turns out to provide an experimental way to verify the numerical study of this process for high carbon steel billet in terms of practical validity.…”

Precipitation, Growth, and Aggregation Behavior of Primary Carbides during Continuous Casting of 6Cr13 Slabs

“…The continuous casting process has the advantage of stability and mass production compared to the electroslag remelting process. Some high-carbon content steels have been industrially produced by the continuous casting process, e.g., GCr15 (C: 1.00%, Cr: 1.50%), [7][8][9][10][11][12][13][14] 82 A, B (C: 0.82%), [15,16] Mn13 (C: 1.00%, Mn: 13.00%), [17,18] etc. The techniques such as cooling rate control, [8,12,14,16] electromagnetic stirring, [7,8,13] soft reduction, [10,11,13] casting speed control, [16,18] and low-superheat casting [12,16] have been used to improve the solidification quality of the continuous casting slab as well as to alleviate the segregation of the alloying elements.…”

“…Some high-carbon content steels have been industrially produced by the continuous casting process, e.g., GCr15 (C: 1.00%, Cr: 1.50%), [7][8][9][10][11][12][13][14] 82 A, B (C: 0.82%), [15,16] Mn13 (C: 1.00%, Mn: 13.00%), [17,18] etc. The techniques such as cooling rate control, [8,12,14,16] electromagnetic stirring, [7,8,13] soft reduction, [10,11,13] casting speed control, [16,18] and low-superheat casting [12,16] have been used to improve the solidification quality of the continuous casting slab as well as to alleviate the segregation of the alloying elements. However, the central segregation of C elements still exists and carbides will precipitate in the regions where the segregation of alloying elements is severe.…”

Optimization of Process Parameters for 40Cr Steel Continuous Casting Round Bloom with Pulsed Magneto‐Oscillation Treatment

“…Due to solute redistribution and forced cooling, the heterogeneous defects, such as macrosegregation and shrinkage cavity, are inevitable in continuous casting and are difficult to eliminate through subsequent processes, which seriously affect the quality of steel products. [ 1,2 ] Hence, a variety of technologies have been developed to improve the homogeneity of casting blooms, such as electromagnetic swirling flow, [ 3,4 ] electromagnetic stirring, [ 5–7 ] soft or heavy reduction, [ 8–11 ] and so on. The pulsed electromagnetic field, with advantages such as low energy consumption, convenient application, and significant effects, has become a research hotspot in the field of solidification structure refinement technology.…”