Influence of Ni2+/Co2+ ratio in electrolyte on morphology, structure and magnetic properties of electrolytically produced Ni−Co alloy powders
Authors
Maksimović, Vesna M.
Kusigerski, Vladan B.

Stoiljković, Milovan

Maletaškić, Jelena

Nikolić, Nebojša D.

Article (Published version)

Elsevier
Metadata
Show full item recordAbstract
Nickel−cobalt (Ni−Co) alloy powders were produced galvanostatically by using sulphate electrolytes with
various ratios of Ni2+/Co2+ (mole ratios). The morphology, phase structure, chemical composition and magnetic
properties were examined by scanning electron microscope (SEM), X-ray diffractometer (XRD), atomic emission
spectrometer (AES), and SQUID-based magnetometer, respectively. Morphology of the particles changed from
cauliflower-like and dendritic to coral-like and spongy-like ones with increasing Ni2+/Co2+ ratio from 0.25 to 4.0. XRD
analysis of the Ni−Co powders revealed that the decrease of Ni2+/Co2+ ratios (the increase of Co content) caused a
change of structure from face centered cubic (FCC) obtained for the ratios of 4.0, 1.5 and 0.67 to a mixture of FCC and
hexagonal closed-packed (HCP) phases for the ratio of 0.25. The increasing content of nickel led to change of
mechanism of electrolysis from irregular (up to ~40 wt.% Ni in the electrolytes) to close to equilib...rium (between
~40 and 60 wt.% Ni in the electrolytes) and anomalous co-deposition (over 60 wt.% Ni in the electrolytes) type. All of
the obtained Ni−Co alloy samples behaved as soft magnetic materials while their magnetic parameters showed
immediate composition dependence since both coercivity and saturation magnetization almost linearly increased with
increase of the Co content.
Keywords:
Ni−Co alloy powders / electrolysis / hydrogen / morphology / magnetic propertiesSource:
Transactions of Nonferrows Metals Society of China, 2020, 30, 4, 1046-1057Publisher:
- Elsevier
Projects:
- Synthesis, processing and characterization of nanostructured materials for application in the field of energy, mechanical engineering, environmental protection and biomedicine (RS-45012)
- Effects of laser radiation and plasma on novel materials in their synthesis, modification, and analysis (RS-172019)
- Magnetic and radionuclide labeled nanostructured materials for medical applications (RS-45015)
DOI: 10.1016/S1003-6326(20)65276-1
ISSN: 1003-6326; 2210-3384