The high microhardness of electrodeposited Fe–C coatings with around 800 HV after electrodeposition increased to about 1300 HV by dedicated annealing, reflecting a huge potential for surface engineering. The coatings remain nanocrystalline during annealing, but co-deposited carbon and oxygen result in temperature-induced phase transformations. Energy-dispersive synchrotron diffraction revealed that carbides and oxides form during annealing of the as-deposited coating, which consisted mainly of carbon-free ferrite. The understanding of occurring precipitations was supplemented and verified by in-situ thermal analysis, which revealed the temperatures of thermal events related to decomposition reactions, the evolution of gasses and associated mass changes during annealing.
- X-ray diffraction (XRD)
- Phase transformations