Abstract: To clarify the evolution of inclusions during cold deformation, cold rolling experiment of 304 stainless steel was conducted through a multi-pass rolling process. The changing behavior of inclusions in morphology, size and distribution was characterized by electron scanning microscopy. Many elongated SiO2–CaO–MnO–Al2O3 inclusions with 5 to 23 μm in length were observed in the hot-rolled plates. During cold rolling, these long-strip inclusions were fractured to finer particles. With increasing cold-rolling reduction, the size of the fractured particles was gradually decreased, but the critical size of the inclusion with no more broken was determined to be about 0.5 μm. In addition, it’s found that the distance between the fractured particles was not related to the original length of inclusion, while mainly depended on the elongation of plates during cold rolling.
Authors: Xueliang Zhang, Shufeng Yang, Jingshe Li, Jun Zhai, and Mengjing Zhao
Keywords: 304 stainless steel, cold rolling, oxide inclusions, fracture