Magnetization and microhardness of iron–chromium alloy films electrodeposited from an aqueous solution containing N, N-dimethylformamide

Iron-chromium (Fe–Cr) alloy films were electrochemically synthesized from an aqueous solution containing N,N-dimethylformamide (DMF). The chromium content of the alloy films increased up to ca. 32 at%, with an increase in the cathodic overpotential during the electrodeposition. Based on the XRD profiles and electron diffraction patterns, it was revealed that the electrodeposited Fe–Cr alloy films have an amorphous nanocrystalline structure. The crystal grain size of the alloys decreased due to an alloying effect of Cr atoms as well as an increase in the nucleation site density of the alloys that were electrodeposited, accompanying a significant overpotential from the stable complex ions. The saturation magnetization of the electrodeposited Fe–Cr alloy films decreased with an increase in the chromium content. On the contrary, the microhardness increased due to the synergistic contribution of solid solution strengthening and crystal grain refinement. The microhardness of the electrodeposited Fe–Cr alloy films reached up to 422.0 kgf/mm2 (HV0.05) and greatly exceeded that of the solidified Fe–Cr alloy ingots.