Loading...

Investigation on Coating of Nonocomposits in Si-Al-O-N System by Plasma Electrolytic Oxidation Technique on Aluminum Substrate and Their Properties

Banifarsi, Sanaz | 2015

767 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 47114 (07)
  4. University: Sharif University of Technology
  5. Department: Materials Science and Engineering
  6. Advisor(s): Faghihi Sani, Mohammad Ali
  7. Abstract:
  8. Aluminum and its alloys have wide applications in industry and recently researches have been expanded in this area. The main reasons are unique features of aluminum corrosion resistance and high strength to weight ratio. The fundamental problem of aluminum is low wear resistance that leads to be worn in industrial applications. For more efficiency of titanium, extensive efforts have been made for solving this problem, one of the best solutions is coating. Plasma electrolyte Oxidation (PEO) is a novel method to create ceramic coatings on metals to improve wear and corrosion resistance. In this research micro and nano Si3N4 particles were added to electrolyte to create alumina-silicate composite coating on aluminum. Effects of current density and Si3N4 concentration on morphology, composition, wear resistance and corrosion behavior of the coatings were studied. Results showed that nano Si3N4 particles with high hardness more than micro Si3N4 prticle had a significant role in improving the wear properties of the coating and also by filling the porosities of discharge channels, can increase the corrosion resistance of the coating. However the polarzation resistance for micro Si3N4 powder was more than nano particle. Thickness of the coating is increased by increasing micro Si3N4 concentration and current density. Energy of discharge channels are boosted with increasing current density and that causes more micro particles attached to the surface. Increasing the concentration of Si3N4 microparticles in the electrolyte leads to attach more Si element to surface. Corrosion resistance for nanoparticle and optimum microparticle senquencly is 81.881 and 186752074.9 KΩ.cm2
  9. Keywords:
  10. Aluminum ; Alumina-Silicate Composite Coating ; Corrosion Resistance ; Plasma Electrolytic Oxidation ; Corrosion Resistance

 Digital Object List

 Bookmark

No TOC