Influence of transformation temperature on carbide precipitation sequence during lower bainite formation

The nature of different carbides formed during the lower bainite reaction at different transformation temperatures was determined by atom probe tomography in three steels with different carbon and silicon contents. It is known that steel composition and temperature alter the carbide precipitation sequence during low-temperature bainite formation. However, present results confirm that dislocations in lower bainite that are more prominent at the lower the transformation temperature, trap a substantial amount of carbon and hence, can influence the carbide precipitation sequence and, in particular, can determine where ɛ-carbide forms before the growth of cementite.