An investigation has been carried out to quantify microstructural evolution during the hot rolling of plain carbon steel strips. In this study, particular attention has been concentrated on austenite grain refinement through recrystallization andgrain growth following recrystallization. It has been demonstrated that the recrystallized grain size increases with either initial grain size or deformation temperature, and decreases with applied strain. Recrystallization-induced austenite grainrefinement is more significant for coarser microstructures. However, there exists a limit for this refinement, the value of which also depends on the above processing parameters. Under industrial mill conditions, particle pinning effect of AIN on thegrain growth following recrystallization in Al-killed plain carbon steels is negligible. Unpinned grain growth plays an important part during rough rolling, but only a minor role during finish rolling. Thus, the final austenite microstructure during hotstrip rolling of steels is mainly determined by the recrystallized grain size, which can be linked to mill processing parameters, such as the applied strain (or reduction), strain rate (or strip velocity) and deformation temperature.
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