Surface Oxide Formation for Differentiated New Steel Grades

New alloy developments provide routes to new markets for steel, but also pose challenges, as these developments are often incremental and time-consuming. New methodologies in rapid alloy protoyping and advanced characterisation enables a faster route to developing and introducing disruptive new grades, which was identified to be a key area for future investigation in a recently launched EPSRC proposal under the "Prosperity Partnership" agenda. As automotive light weighting is key for emission reduction in conventional combustion vehicles and range extension in electric vehicles, new steel grades based on the C-Mn-Si-Cr compositional space provides the next generation enhanced ductility ultra-high strength cold rolled and galvanised automotive steel. Knowledge of oxidation occurring during processing is crucial to guarantee the surface quality of flat steels. The alloying elements added to the steel affect both the kinetics of iron oxide formation and the formation of complex oxides in the (sub)surface at high temperatures and changes introduced in the microstructure during processing also modify the oxide kinetics. The overall aim of this project is to develop a protocol for using the small-scale Rapid Alloy Processing (RAP) Route at WMG to imitate the oxidation conditions in the processing route. Oxidation kinetics and mechanisms will be investigated using a range of advanced electron and ion-microscopy techniques. The data and insights obtained will feed directly into ongoing modelling activities on (oxide) phase stability and consideration will be given to implementing the methods developed into the Tata Steel small-scale experimental route.