Processing and thermal treatment of manganese – silicate inclusion containing steels

Controlling the composition, size and microstructure of oxide inclusions, whose presence is practically unavoidable in steels, is a major goal within the steelmaking industry due to their significant impact on the material’s physical, chemical, and mechanical properties. Understanding the influence of these inclusions on the steel requires detailed characterization of their local properties, including their micro-mechanical behavior, chemical composition, and microstructure. A key step towards this goal is the reproducible production of inclusion-containing steel samples with defined compositions of both the steel and the oxide inclusions it contains. Among the different types of inclusions, manganese-silicates are particularly interesting due to their low melting temperatures, deformability during hot working, and low elastic mismatch compared to the iron matrix.

In this semester project, the student will produce lab-scale samples of near-eutectoid steel compositions with the focus of exploring differing routes for the precipitation of manganese-silicate oxide stochiometries, namely rhodonite (MnSiO3) and tephroite (Mn2SiO4). Addition of carbon to iron, then oxygen incorporation, and lastly manganese and silicon deoxidation, will be carried out using different melting techniques, notably arc-melting. Processing routes and subsequent heat treatments will be investigated to obtain uniform and reproducible microstructures. Specimens will be prepared by standard metallographic techniques for microstructural and compositional characterization, including optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).

Responsible supervisors: David Hernández Escobar and Sándor Lipcsei

Contact: [email protected] and [email protected]