Harun Gul

The Preparation of Zeolite/Ag Composite Powders by Electroless Deposition Process

Core-shell Ag-coated zeolite composite powders were synthesized using silver electroless deposition process, which was carried out in an ammonia-based coating solution containing silver nitrate as a precursor material. The influence of the chemical components and powder concentration in the Ag coating was investigated by scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction techniques. The zeolite/Ag composite powders were fabricated in order to find an antibacterial material and a new implant material based on the microstructural change of zeolite/Ag composites powders using different parameters of Ag deposition.

Ni/MWCNT Coatings Produced by Pulse Electrocodeposition Technique

Nickel/multiwalled carbon nanotube (MWCNT) metal matrix composite coatings were deposited by pulse electrocodeposition method from a Watts-type electrolyte. The influence of the MWCNT content in the electrolyte on the particle codeposition and distribution, the surface morphology, microstructure, microhardness of nanocomposite coatings were studied. Copper substrates were used for electrocodeposition of Ni matrix/MWCNTs with the diameter of 50–60 nm and length of 10-µm carbon nanotube reinforcements. The electrodeposited Ni matrix coatings were characterized by scanning electron microscopy and X-ray diffraction analysis.

A reciprocating wear study on the effect of surfactant concentration and sliding speed in the electro codeposited Ni/SiCp metal matrix composites

In this present work, Ni/SiC metal matrix composite coatings were prepared from a modified Watt’s type electrolyte containing nano-SiC suspended particles by direct current plating method to increase the wear resistance of Ni. The influence of surfactant content on codeposition of SiC particles within the matrix and tribological properties were investigated. A wide particle size range (between 0.1 and 1.0 µm) was chosen to provide a high load bearing ability for the codeposited layers. The wear tests were carried out at different sliding speeds by using a constant load. The influence of sliding speed on the tribological performances of the coatings has been investigated by using a reciprocating ball-on disk apparatus. Wear resistances and friction coefficients of Ni/SiC composites were decreased by increasing sliding speed due to temperature-controlled surface oxidation. The change in wear mechanisms by changing surfactant content and sliding speeds were also comprehensively studied.