Novel Sn-Fe-Co-Ni alloy coatings were deposited by pulse plating method and also by direct current method on copper substrates from an aqueous gluconate-based electrolyte. For the first time, pulse plating conditions for the preparation of novel Sn-Fe-Co-Ni coatings were established. For the characterization of the electroplated alloys, 57Fe and 119Sn Conversion Electron Mössbauer Spectroscopy (CEMS), X-ray diffractomery (XRD), scanning electronmicroscopy (SEM), energy-dispersive X-ray spectroscopy (EDAX) and electrochemical polarisation curves were used. In the case of coatings plated with suitable pulses of high current density, XRD revealed fully amorphous structure, while 57Fe CEMS showed magnetically split spectra with amorphous character. Furthermore, 119Sn CEMS also exhibited magnetically split spectra due to transferred hyperfine fields. EDAX reflected homogeneous composition within the deposits and SEM micrographs indicated adherent, bright, uniform alloy coatings with nanospheres in the case of pulse plating. The short range order of ferromagnetic amorphous Sn-Fe-Co-Ni quaternary alloys was found to be different for DC- and pulse-plated deposits.
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