Analysis of Microstructure Evolution during Steckel Mill Rolling of AISI304 Stainless Steel

The microstructural evolution in AISI304 austenitic stainless steel during Steckel mill rolling has been investigated. Particular emphasis is placed on the microstructural behaviour of the strip ends relative to the strip bulk. Good correlation between the development of hard ends that arise in the final strip and strip temperature and mean flow stress has been found by analysing mill log data. Measurement of the recrystallization kinetics under conditions that simulate Steckel mill rolling have shown that deformation temperatures below 950°C can lead to incomplete recrystallisation during the Steckel mill inter-pass. Predictions of the time to 50% recrystallisation (t0.5) are used to quantify the recrystallisation kinetics of the strip ends.