STUDY OF CHARACTERIZATION AND CORROSION RESISTANCE OF NIP/NANO-DIAMOND ELECTROLESS COMPOSITE DEPOSITION

Ni-P Electroless coatings provide appropriate resistance to wear and corrosion. Co-deposition of particles between layers can improve their properties, especially general corrosion and erosion-corrosion behavior by means of nano diamond as reinforcing particles. In this study Ni-P/nano diamond composite deposition were deposited on steel substrate. Structure of the coatings and corrosion resistance of theme were investigated by scanning electron microscopy and corrosion tests in salty media. The composite structure of the deposit was evaluated as nano size without using any surfactants. Also results for the composite coating show better corrosion protection and higher hardness comparing with as -deposited Ni-P. The optimum concentration of diamond nanometer particles were found by evaluation of scanning electron microscopy pictures, hardness measurement, linear polarization and electrochemical impedance spectroscopy results.