Loading...

Pulse Electrodeposition of Ni-Fe Composite Coating with Nano-TiO2 Particles and its Properties

Mehdizadeh, Reza | 2010

1292 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 42382 (07)
  4. University: Sharif University of Technology
  5. Department: Materials Science and Engineering
  6. Advisor(s): Ghorbani, Mohammad
  7. Abstract:
  8. In this study, pulse electrodeposition of Ni-Fe composite coating with and without nano-TiO2 particle in sulphate bath was performed and effects of peak current density, frequency, duty cycle and type of current on their properties was investigated. Also effect of pulse parameters on the composition and amount of particles in coatings was determined. Scanning Electron Microscopy (SEM), Field Emission Scanning Electron Microscopy (FESEM) and X-ray Diffraction (XRD) analysis was used to study the morphplogy and structure of coatings. The chemical composition of deposits was examined by Energy Dispersive X-ray Spectroscopy (EDS) attached with Scanning Electron Microscopy and Atomic Adsorption Spectroscopy (AAS). Corrosion testing of coatings by potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) in solution 3.5% NaCl was investigated. To study the mechanical properties of the coatings, hardness and wear resistance tests was performed.
    With addition of 5 "(" "g" /"L" ")" titania nano-particles in the bath, corrosion resistance of deposits decreased but in Ip=20 "(" "mA" /〖"cm" 〗^"2" ")" , f=10 (Hz) and =10% improved and the hardness of coatings increased. Incorporation of nano-particles caused the friction coefficient of the deposits decreased and wear resistance significantly improved. In Ip=20 "(" "mA" /〖"cm" 〗^"2" ")" , f=10 (Hz) and =75%, atomic percent of nano-particles in deposit increased to 6.41 also hardness and wear loss of coat reached to 755 (Hv) and 0.1 (mg). with varing the type of current to direct (DC) and codeposition of nano-particles, roughness of Ni-Fe Coating decreased. Also with direct current technique, corrosion resistance of Ni-Fe coating increased. X-ray Diffraction test showed that the addition of 2.59 (At%) TiO2 in Ni-Fe matrix didnot change the growth orientation of crystal face of deposit but grain size of Ni-Fe coating decreased from 11 (nm) to 9 (nm).
  9. Keywords:
  10. Pulse Elctrodeposition ; Nano-Composite Coating ; Nanoparticles ; Titania ; Titanium Oxide ; Nickel-Ferrite Alloy

 Digital Object List

  • محتواي پايان نامه
  •   view

 Bookmark

...see more