Influence of “Soft” Reduction on the Structure of Continuous Cast Ingot and the Properties of Rolled Products of Microalloyed Steels
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We study the efficiency of application of a system of soft reduction in the process of crystallization of a continuously cast slab (ССS) on the installation for continuous casting of steel at the “MMC” PJSC by comparing the macrostructures of ССS for different pipe steels obtained by applying the system of soft reduction and without it. On the basis of the results of normative assessment of the level of axial liquation in the slabs, we revealed a decrease in the chemical inhomogeneity in the axial zone after soft reduction. The influence of soft reduction on the structure and mechanical properties of rolled sheet is demonstrated. This influence leads to a decrease in segregation in hot-rolled products. We also established the characteristics of quality of the rolled products whose dependence on the presence of macrodefects in the structure of CCS is especially pronounced, as well as their changes caused by the soft reduction of slabs.
Keywordspipe steel continuously cast slabs soft reduction macrostructure microstructure liquation plate steel
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