New steel processing technologies require an in-depth understanding of the processing-microstructure-property synergism of current and future steels. The need for this basic understanding is to improve the properties of the steels and to make them commercially more competitive. This study systematically examines the microstructure evolution in the as-cast and as-equilibrated conditions of two low-carbon Nb-bearing microalloyed HSLA steels commercially produced by the Compact Strip Production (CSP) process. Particular attention is paid to the precipitation that takes place through the processing conditions studied in this work. The formation of complex (Nb, Ti)(C, N) precipitates with a "star-like" shape was the primary type of precipitates found. The kinetics of formation and dissolution of the star-like precipitates at different re-heating temperatures is examined. A comparison between the as-cast, as-equilibrated and hot band conditions is also presented.
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