Hot Temperature Deformation Mechanisms of Complex Oxide Inclusions in Fe–Si–Mn Alloys with Varying Aluminum Contents

This study delves into the deformation mechanisms of complex oxide inclusions in Fe–Si–Mn alloys with varying aluminum contents, focusing on their properties and behavior during hot rolling. The research examines how increasing aluminum content affects the composition, liquidus temperature, viscosity, crystallization ability, and Young’s modulus of these inclusions. Key findings reveal that as aluminum content rises, the inclusions transform from a CaO–MnO–Al2O3–SiO2 system to a CaO–Al2O3–SiO2 system, and eventually to CaO–Al2O3 and Al2O3 types. The study highlights the inverse relationship between the average aspect ratio of inclusions and their average Al2O3 content, indicating reduced deformability with higher aluminum levels. Additionally, the crystallization ability of inclusions is characterized by the parameter ηm, which increases with higher Al2O3 content, making viscosity calculations based on a glassy state assumption inadequate. The Young’s modulus of crystalline and glassy inclusions is compared, showing significant differences for CA6 and Al2O3, with crystals exhibiting much higher moduli. The high-temperature Young’s modulus data is supplemented, revealing that the modulus of SiO2 increases with temperature, unlike other oxides. The study concludes by characterizing the deformation of inclusions with different compositions based on their properties, emphasizing the importance of controlling aluminum content in industrial steel production to optimize inclusion deformability. This comprehensive analysis provides valuable insights into the behavior of oxide inclusions in steel alloys, offering practical implications for improving material properties and processing techniques.