Electrodeposition of Fe-C Alloys from Citrate Baths: Structure, Mechanical Properties, and Thermal Stability

A new citrate-based electrolyte is proposed for the electrodeposition of thick Fe-C films. The structure and properties of the deposits are compared to those from another electrolyte previously reported in the literature. Both consist of a nanocrystalline single-phase structure with a grain size of 20 nm, which results in a hardness of up to 660 HV. Due to its higher growth rate, the new electrolyte is a promising candidate for the deposition of thick films. However, the codeposition of oxygen causes embrittlement, limiting the application of the deposits from both the new and the known electrolyte. On the other hand, the codeposited carbon and oxygen provide considerable thermal stability and even a hardening capacity upon annealing. The results are compared and discussed with respect to the previous investigations of electrodeposited Fe-C alloys