The influence of aluminium upon continuous cooling transformation (CCT) diagrams for hot rolled ferrite–martensite dual phase steel is investigated, with continuous cooling experiments performed through the use of dilatometry. Results indicate that additions of aluminium significantly raise the Ar3 and Ar1 temperatures accounting for the increased polygonal ferrite stabilisation during cooling. Acceleration of ferrite transformation is observed, with aluminium displacing both ferrite and pearlite transformations to the left of the CCT diagram. Aluminium is also seen to suppress bainite formation and decrease the martensite start temperature by increasing the hardenability within austenite grains.
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