Understanding the Role of Ti in Particle Formation and Microstructure Refinement in Fe-C-O-Ti Alloys

Fe-C-O-Ti alloys with various Ti contents have been designed to promote recycling of resources and present an experimental scheme profiling the role of Ti alone on the particle features and microstructural characteristics. It is found that increasing the Ti content promotes formation of Ti oxides and Ti sulfides. Concurrently, the main microstructure gradually transforms from ferrite to bainite, while the prior austenite grain size and effective grain size are significantly refined, which contributes to enhancing the strength according to the prediction by the classical Hall–Petch equation.