Microstructural analysis of hot-rolled, low-carbon steel strips

Samples obtained from hot-rolled, low-carbon steel strips were subjected to a series of microstructural analyses to study the mechanisms responsible for their differences in mechanical behavior. The strips used in this study had the same composition and thickness but were produced in two different hot-rolling mills. The first one is a conventional second-generation mill, where the steel is cast in ingots and reheated in soaking pits before being hot rolled. The second one is a compact mill, where the steel is continuously cast into thin slabs and reheated in a continuous tunnel furnace before being rolled. Tensile specimens were machined at three different directions with respect to the rolling direction. Samples of both types of strips were prepared for metallographic inspection. Textural information was obtained by back-scattered electron diffraction using a scanning electron microscope (SEM). It was found that the differences in mechanical behavior were due not only from dissimilarities in their grain size but also due to variation in their textural components.