THE PRODUCTION OPPORTUNITIES OF THE HOT-ROLLED DUAL-PHASE STEEL WITH SINGLE-STAGE COOLING ON THE RUNOFF TABLE OF HOT-ROLLING MILL 2000 AT JSC “NLMK”

The purpose of these studies was to find opportunities to provide the mechanical properties of hot-rolled dual-phase steel in the range of strength class DP 450–600 at “NLMK”. In this case decisive role in the formation of the final structure and properties acquires a one-stage cooling strip strategy on the run-out table in the conditions of hot rolling mill 2000 at “NLMK”. The laboratory investigations have been conducted on the influence of hot rolling parameters on the structure and mechanical properties of steel grade SPRC440R, used by “NLMK” for the production of cold-rolled dual-phase steels. The temperature-speed parameters of accelerated cooling on the run-out table of hot-rolling mill 2000 at “NLMK” were calculated by mathematical model in order to realize the rolling experiment. The results of laboratory investigations and the carried out calculations were used for the development and implementation at experimental-industrial rolling conditions. In this article authors give recommendations for the possibility of providing the mechanical properties of hot-rolled dual-phase steel in the range of strength class DP 450–600. 

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