Mechanical and physical properties of electrodeposited Ni-Fe, WO3 doped nanocomposite

- Unusual strength of nanocomposite (microhardness up to 1450 HV).
- Coatings possess very low electrical resistivity (1.04 × 10− 8 Ω cm), ordered structure and little imperfections.
- The nanocomposite showed superparamagnetic behavior at room temperature (300 K).
- Conductivity of ceramic particles alters relative texture (RTC).
- Improved corrosion resistance of Ni-Fe/WO3 nanocomposite than Ni-Fe alloy.

The mechanical and magnetic properties of Ni-Fe alloy deposits may be controlled by compositional tailoring and reinforcement by ceramics. The incorporation of high content of ceramic particles in the alloy matrix has, however, detrimental effect on electrical and magnetic properties of the nanocomposites. Here, electrodeposition of WO3 nanoparticle (spheroidal shaped, 20-40 nm) doped Ni-Fe nanocomposites has been carried out in an organic bath at various current densities. The particle content in coating was found up to ~ 2.0 wt%. Field emission scanning electron microscope (FESEM), energy dispersed X-ray analyzer (EDAX) and atomic force microscopic (AFM) examinations revealed a distinct change in morphology of the deposit due to inclusion of the particles in the matrix. X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies showed fcc lattice of the matrix and a shift in preferred orientation of the coating from (111) to (220) crystallographic planes with increasing current density. Significant enhancement in the microhardness of the coatings was observed on incorporation of only 1.25 wt% WO3 particles due to solid solution hardening and dispersion hardening. An improvement in the conduction and corrosion resistance of the coatings over matrix has also been noticed due to dispersion of the ceramic particles in the matrix. Magnetic studies point to ferromagnetic behavior of the nanocomposite which also has the tendency of superparamagnetism.