Enhanced corrosion resistance of next generation martensitic stainless steel for future energy sector

This study investigates cryogenic processing (CP), an alternative green technology, for improving corrosion resistance in energy sector applications, including fusion. CP opens the door to new tailoring options for materials used in extreme conditions by tailoring the microstructure of the materials and, consequently, their final properties, such as corrosion resistance. The resulting microstructural changes were confirmed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), electron backscatter diffraction (EBSD), X-ray diffraction (XRD), transmission electron microscopy (TEM), atom probe tomography (APT), and additional in-situ and ex-situ scanning photoelectron microscopy (SPEM) observations tailors microstructural evolution directly after its application, and later during tempering. The corrosion behaviour was tested using potentiodynamic measurements and exposure to different corrosive environments (nitrogen/oxygen atmosphere with high humidity) in scanning Kelvin probe force microscopy (SKPFM) in order to observe the growth of the passive layer and changes in surface potential. Investigating the corrosion properties and microstructural features together clarifies the formation of carbides over intermetallic enrichment zones, which stabilises the microstructure. The development of next-generation metallic materials for current and future energy sectors is facilitated by this pioneering work, which provides important research for the application of CP.